U.S. patent application number 17/581514 was filed with the patent office on 2022-05-12 for plants and methods for high density plant production.
The applicant listed for this patent is MONSANTO TECHNOLOGY LLC. Invention is credited to Juan CORDERO, Daniel Joseph OVADYA, Kyle B. SMITH, Adrian VARGAS.
Application Number | 20220142062 17/581514 |
Document ID | / |
Family ID | 1000006097815 |
Filed Date | 2022-05-12 |
United States Patent
Application |
20220142062 |
Kind Code |
A1 |
CORDERO; Juan ; et
al. |
May 12, 2022 |
PLANTS AND METHODS FOR HIGH DENSITY PLANT PRODUCTION
Abstract
Provided are methods for growing a plant under certain stressed
conditions that alter the morphology of the plant. In certain
aspects, however, although the plant is altered and may be
undesirable for commercial purposed, the plant still produces an
adequate number of seeds for breeding purposes. Further, because
plants may be smaller in size, they can be grown at higher
densities, allowing the production of large populations of plants
to be brought under controlled conditions which can exclude
pollinating insects and thus increase the genetic purity achievable
in a breeding program.
Inventors: |
CORDERO; Juan; (St. Louis,
MO) ; OVADYA; Daniel Joseph; (St. Louis, MO) ;
SMITH; Kyle B.; (St. Louis, MO) ; VARGAS; Adrian;
(St. Louis, MO) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MONSANTO TECHNOLOGY LLC |
St. Louis |
MO |
US |
|
|
Family ID: |
1000006097815 |
Appl. No.: |
17/581514 |
Filed: |
January 21, 2022 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16470054 |
Jun 14, 2019 |
11229167 |
|
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PCT/US2017/066623 |
Dec 15, 2017 |
|
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17581514 |
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62435209 |
Dec 16, 2016 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A01G 7/06 20130101; A01N
43/40 20130101; A01H 1/12 20210101; A01G 22/50 20180201; A01G 25/00
20130101 |
International
Class: |
A01G 22/50 20060101
A01G022/50; A01N 43/40 20060101 A01N043/40; A01G 7/06 20060101
A01G007/06 |
Claims
1-56. (canceled)
57. A population of cotton plants with an altered morphology,
wherein the population is in a controlled environment, wherein the
average density of the cotton plants in the population is at least
10 plants per square meter and the plants at the density are in an
average volume of growth media of less than about 1,000 mL per
plant, and wherein at least about 70% of the individual cotton
plants in the population are between about 12 inches and 24 inches
tall and have at least one boll that contains at least 20
seeds.
58. The population of claim 57, where the average density of the
plants in the population is at least 30 plants per square
meter.
59. The population of claim 57, wherein the plants are at the
density in an average volume of growth media of less than about 500
mL per plant.
60. The population of claim 57, wherein at least about 80% of the
individual cotton plants in the population are between about 12
inches and 24 inches tall and have at least one boll that contains
at least 20 seeds.
61. The population of claim 57, wherein at least about 70% of the
individual cotton plants in the population are between about 12
inches and 18 inches tall and have at least one boll that contains
at least 20 seeds.
62. The population of claim 61, wherein at least about 80% of the
individual cotton plants in the population are between about 12
inches and 18 inches tall and have at least one boll that contains
at least 20 seeds.
63. The population of claim 57, wherein the population comprises at
least about 1,000 cotton plants.
64. The population of claim 63, wherein the population comprises at
least about 10,000 cotton plants.
65. The population of claim 64, wherein the population comprises at
least about 100,000 cotton plants.
66. The population of claim 57, wherein the controlled environment
is substantially free of pollinating insects.
67. The population of claim 57, wherein the population of plants is
grown at a temperature of at least about 36.degree. C. for at least
about 2 hours per day, for at least 50 days during the time from
the average day of germination of the cotton seeds of the
population to the average day that the plants produce at least one
cotton boll that contains a seed.
68. The population of claim 67, wherein the population of plants
are grown at a temperature of at least about 37.degree. C. for at
least about 2 hours per day, for at least 50 days during the time
from the average day of germination of the cotton seeds of the
population to the average day that the plants produce at least one
cotton boll that contains a seed.
69. The population of claim 57, wherein the population of plants is
grown while providing less than about 400 mL of water per day on
average, for at least 50 days during the time from the average day
of germination of the cotton seeds of the population to the average
day that the plants produce at least one cotton boll that contains
a seed.
70. The population of claim 69, wherein the population of plants
are grown while providing less than about 300 mL of water per day
on average, for at least 50 days during the time from the average
day of germination of the cotton seeds of the population to the
average day that the plants produce at least one cotton boll that
contains a seed.
71. The population of claim 57, wherein the population of plants is
grown at a temperature of at least about 36.degree. C. for at least
about 2 hours per day, for at least 50 days during the time from
the average day of germination of the cotton seeds of the
population to the average day that the plants produce at least one
cotton boll that contains a seed and growing the cotton plants
while providing less than about 400 mL of water per day on average,
for at least 50 days during the time from the average day of
germination of the cotton seeds of the population to the average
day that the plants produce at least one cotton boll that contains
a seed.
72. The population of claim 57, wherein at least about 80% of the
individual cotton plants in the population are between about 12
inches and 24 inches tall and have at least one boll that contains
at least 20 seeds.
73. The population of claim 57, wherein a plant growth regulator
selected from the group consisting of chlormequat-CL, mepiquat-CL,
AMO-1618, clorphonium-Cl, tetcylacis, ancymidol, flurprimidol,
paclobutrazol, uniconazole-P, inabenfide, prohexadione-CA,
trinexapac-ethyl, daminozide, exo-16,17-, dihydro-GA5-13-acetate,
systemin, phytosulfokine, and rapid alkalinization factor is
applied to the population of plants.
74. The population of claim 73, wherein the plant growth regulator
is mepiquat-CL.
75. The population of claim 73, wherein about 0.5 mL of the plant
growth regulator is applied per plant.
76. The population of claim 73, wherein the plant growth regulator
is applied about 20 days after planting.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application 62/435,209, filed on Dec. 16, 2016, which is
incorporated by reference herein in its entirety.
BACKGROUND
[0002] The goal of plant cultivation is generally to provide
growing conditions, such as irrigation, light, spacing, temperature
and access to nutrients that promote healthy plant growth,
including achieving a certain size and producing a number of seeds
or fruit typical of a healthy plant. For example for cotton, which
is shrubby plant that grows to be about 3 to 5 feet tall, typical
commercial plantings have a plant density of about 8 to 12 plants
per square meter with rows spaced about 1 meter apart. This spacing
has been developed to optimize crop performance by generally
increasing yield per unit area and minimizing disease
susceptibility.
[0003] The large amount of space, however, needed to grow large
populations of plants such as cotton is an obstacle to growing
plants in controlled environments, such as green houses or grow
houses, where not only can conditions such as temperature, light,
and water be controlled, but the presence of pollinating insects
minimized. This would be especially advantageous in breeding
programs where the genetic purity resulting from crosses can be
increased due to the lack of interference from pollinating insects.
Increases in genetic purity translate into higher efficiencies
and/or lower costs in breeding programs. Further the
synchronization of flowering may also translate into higher
efficiencies and/or lower costs in breeding programs by reducing
overall cycle time and resource waste.
[0004] Therefore, there remains a need for methods of growing
plants for use in more efficient breeding programs that are
feasible in light of the space limitations.
SUMMARY
[0005] Provided herein are methods of producing a cotton seed by
growing a cotton plant from a cotton seed under a stressed
condition. It is understood that reference to "an aspect" refers to
any of the methods disclosed herein and should not be limited to
any particular method unless otherwise stated. In certain aspects,
the stressed condition comprises growing the cotton plant in a
volume of growth media of less than about 2,000 mL, less than about
1,500 mL, less than about 1,000 mL, less than about 500 mL, less
than about 450 mL, less than about 350 mL, less than about 250 mL,
or less than about 200 mL, for at least 40 days, for at least 50
days, for at least 60 days, for at least 70 days, for at least 75
days, or for at least 80 days during the time from when the cotton
seed germinates to when the cotton plant produces at least one
cotton boll that contains a seed, wherein the seed comprises at
least one embryo with a cotyledon in the primordia stage and
optionally wherein the seed comprises a black layer (restricted
growth media volume). In certain aspects, the stressed condition
comprises growing the cotton plant at a temperature of at least
about 37.degree. C., 38.degree. C., 39.degree. C., 40.degree. C.,
41.degree. C., 42.degree. C., 43.degree. C., 44.degree. C.,
45.degree. C., 46.degree. C., 47.degree. C., or 48.degree. C., for
at least about 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 hours per day,
for at least 40 days, for at least 50 days, for at least 60 days,
for at least 70 days, for at least 75 days, or for at least 80 days
during the time from when the cotton seed germinates to when the
cotton plant produces at least one cotton boll that contains a
seed, wherein the seed comprises at least one embryo with a
cotyledon in the primordia stage and optionally wherein the seed
comprises a black layer (high temperature). In certain aspects, the
stressed condition comprises growing the cotton plant by providing
less than about 500 mL, less than about 400 mL, less than about 300
mL, less than about 200 mL, less than about 100 mL, or less than
about 50 mL of water per day on average, for at least 40 days, for
at least 50 days, for at least 60 days, for at least 70 days, for
at least 75 days, or for at least 80 days during the time from when
the cotton seed germinates to when the cotton plant produces at
least one cotton boll that contains a seed, wherein the seed
comprises at least one embryo with a cotyledon in the primordia
stage and optionally wherein the seed comprises a black layer
(restricted irrigation). In certain aspects, the stressed condition
can be a combination of any of these.
[0006] In certain aspects, the method comprises growing a cotton
plant from a cotton seed under the stressed condition of:
restricted growth media volume and/or restricted irrigation,
wherein the cotton plant is also grown at a temperature of at least
about 32.degree. C., 33.degree. C., 34.degree. C., 35 .degree. C.,
or 36.degree. C. for at least about 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
or 12 hours per day, for at least 40 days, for at least 50 days,
for at least 60 days, for at least 70 days, for at least 75 days,
or for at least 80 days during the time from when the cotton seed
germinates to when the cotton plant produces at least one cotton
boll that contains a seed, wherein the seed comprises at least one
embryo with a cotyledon in the primordia stage and optionally
wherein the seed comprises a black layer.
[0007] In certain aspects, the days during which the cotton plant
is grown under restricted growth media volume and/or restricted
irrigation correspond to the days during which the plant is grown
at a temperature of at least about 32.degree. C., 33.degree. C.,
34.degree. C., 35.degree. C., 36.degree. C., 37.degree. C.,
38.degree. C., 39.degree. C., 40.degree. C., 41.degree. C.,
42.degree. C., 43.degree. C., 44.degree. C., 45.degree. C.,
46.degree. C., 47.degree. C., or 48.degree. C., for at least about
2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 hours a day. In certain
aspects, the plant is grown at a nighttime temperature of about
18.degree. C. to 22.degree. C. In certain aspects, on at least
about 50%, 60%, 70%, 80%, 90%, 95%, 98%, or 100% of the days on
which the plant is grown at a temperature of at least about
37.degree. C., 38.degree. C., 39.degree. C., 40.degree. C.,
41.degree. C., 42.degree. C., 43.degree. C., 44.degree. C., or
45.degree. C., it is not grown at this temperature for more than
about 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16, 18, or 20 hours
per day. In certain aspects, on at least about 50%, 60%, 70%, 80%,
90%, 95%, 98%, or 100% of the days on which the plant is grown at a
temperature of at least about 37.degree. C., 38.degree. C.,
39.degree. C., 40.degree. C., 41.degree. C., 42.degree. C., 43
.degree. C., 44.degree. C., or 45.degree. C., the plant is also
grown at a temperature of about 18.degree. C. to 22.degree. C. for
at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16
hours per a day.
[0008] In certain aspects, the cotton plant is grown at least under
the stress condition of restricted growth media volume. In certain
aspects, the cotton plant is grown at least under the stress
condition of high temperature. In certain aspects, the cotton plant
is grown at least under the stress condition of restricted
irrigation.
[0009] In certain aspects, the cotton plant grown under a stressed
condition and having produced at least one cotton boll that
contains a seed, wherein the seed comprises at least one embryo
with a cotyledon in the primordia stage is of a diminished size,
such as decreased in height, shortened internode length and/or
having reduced biomass, compared to a control plant.
[0010] In certain aspects, the cotton plant is grown in a
controlled environment.
[0011] In certain aspects, the cotton plant is grown in a volume of
growth media of from any of about 200 mL, 250 mL, 300 mL, 350 mL,
or 400 mL to any of about 300 mL, 350 mL, 400 mL, or 500 mL, for at
least 40 days, for at least 50 days, for at least 60 days, for at
least 70 days, for at least 75 days, or for at least 80 days during
the time from when the cotton seed germinates to when the cotton
plant produces at least one cotton boll that contains a seed,
wherein the seed comprises at least one embryo with a cotyledon in
the primordia stage and optionally wherein the seed comprises a
black layer.
[0012] In certain aspects, the method further comprises applying a
plant growth regulator (PGR) to the cotton plant before the first
pinhead square stage. In certain aspects, the method further
comprises applying a PGR to the cotton plant at a day not past 20
days, 21 days, 22 days, 23 days, or 25 days after germination. In
certain aspects, the method comprises applying a PGR at 20 to 25
days after germination, 20 to 24 days after germination, 21 to 23
days after germination, or 22 to 24 days after germination. In
certain aspects, the PGR is a compound known to inhibit the
synthesis, update, or persistence of gibberellic acid in a plant.
Further, In certain aspects, the PGR is selected from the group
consisting of chlormequat-CL, mepiquat-CL, AMO-1618,
clorphonium-Cl, tetcylacis, ancymidol, flurprimidol, paclobutrazol,
uniconazole-P, inabenfide, prohexadione-CA, trinexapac-ethyl,
daminozide, exo-16,17-, dihydro-GA5-13-acetate, systemin,
phytosulfokine, and rapid alkalinization factor. And, in certain
aspects, the PGR is mepiquat chloride.
[0013] In certain aspects, the cotton plant having produced at
least one cotton boll that contains a seed, wherein the seed
comprises at least one embryo with a cotyledon in the primordia
stage, is less than about 30 inches tall, less than about 24 inches
tall, less than about 18 inches tall, less than about 15 inches
tall, or less than about 12 inches tall. In certain aspects, the
cotton plant having produced at least one cotton boll that contains
a seed, wherein the seed comprises at least one embryo with a
cotyledon in the primordia stage, has at least 20 seeds, at least
30 seeds, at least 40 seeds, at least 50 seeds, or at least 60
seeds.
[0014] In certain aspects, the seed of the cotton plant grown under
a stressed condition is used in a breeding program. Certain aspects
comprise collecting at least one seed from the plant grown under a
stressed condition. In certain aspects, the method further
comprises testing at least one collected seed or a plant grown from
the collected seed. The testing can be, for example, genotyping
and/or phenotyping for genetic and/or physical characteristics and
traits. In certain aspects, the method further comprises selecting
a cotton plant to grow based on the testing. In certain aspects,
the method further comprises crossing a cotton plant based on the
testing.
[0015] In certain aspects, the cotton plant grown under a stressed
condition is a member of a population of cotton plants grown at an
average density of at least 10, 30, 60, 75, 100, 125, or 150 plants
per square meter. In certain aspects, the population of plants
comprises at least about 50 cotton plants, at least about 100
cotton plants, at least about 500 cotton plants, at least about
1,000 cotton plants, at least about 5,000 cotton plants, at least
about 10,000 cotton plants, at least about 100,000 cotton plants,
at least about 500,000 cotton plants, or at least about 1,000,000
cotton plants. Similarly, in certain aspects, the population of
plants comprises 50 or more cotton plants, 100 or more cotton
plants, 500 or more cotton plants, 1,000 or more cotton plants,
5,000 or more cotton plants, 10,000 or more cotton plants, 100,000
or more cotton plants, 500,000 or more cotton plants, or 1,000,000
or more cotton plants. In certain aspects, the cotton plant grown
under a stressed condition is grown as a member of a population of
cotton plants at an average density of at least 10, 30, 60, 75,
100, 125, or 150 plants per square meter, for at least 40 days, for
at least 50 days, for at least 60 days, for at least 70 days, or
for at least 80 days during the time from when the cotton seed
germinates to when the cotton plant produces at least one cotton
boll that contains a seed, wherein the seed comprises at least one
embryo with a cotyledon in the primordia stage. In certain aspects,
at least about 50%, 60%, 70%, 80%, 90%, 95%, 98%, or 99% of the
cotton plants in the population have reaches a stage in their life
cycle wherein pinhead squares have formed. In certain aspects, the
population of plants is grown in a controlled environment.
[0016] Provided herein are methods of producing a population of
cotton plants by: collecting at least one seed produced by a cotton
plant grown under a stressed condition according to any of the
aforementioned methods; testing (e.g., genotype and/or phenotype)
at least one collected seed or plant grown from the collected seed;
and growing and/or crossing a cotton plant based on said testing to
produce a population of cotton plants.
[0017] Provided herein are methods of breeding cotton plants by:
collecting at least one seed produced by a cotton plant grown under
a stressed condition according to any of the aforementioned
methods. In certain aspects, the seed is tested (e.g., genotyped
and/or phenotyped) to determine the performance of, and/or a
characteristic of, a parent plant and/or the offspring a plant
produces.
[0018] Provided herein are cotton plants with an altered
morphology. It is understood that reference to "an aspect" refers
to any of the cotton plants with an altered morphology disclosed
herein and should not be limited to any particular plant unless
otherwise stated. In certain aspects, the cotton plant is less than
about 30 inches, less than about 24 inches, less than about 18
inches, less than about 15 inches, or less than about 12 inches,
and wherein the plant has at least 20 seeds, at least 30 seeds, at
least 40 seeds, at least 50 seeds, or at least 60 seeds. In certain
aspects, the plant is grown according any of the aforementioned
methods.
[0019] Provided herein are methods of growing a population of
cotton plants, wherein the cotton plants have an altered
morphology, by growing under a stressed condition a population of
cotton plants from cotton seeds. As stated above, it is understood
that reference to "an aspect" refers to any of the methods
disclosed herein and should not be limited to any particular method
unless otherwise stated. In certain aspects, the stressed condition
comprises growing the cotton plants of the population in an average
volume per plant of growth media of less than about 2,000 mL, less
than about 1,500 mL, less than about 1,000 mL, less than about 500
mL, less than about 450 mL, less than about 400 mL, less than about
300 mL, less than about 250 mL, or less than about 200 mL, for at
least 40 days, for at least 50 days, for at least 60 days, for at
least 70 days, for at least 75 days, or for at least 80 days during
the time from the average day of germination of the cotton seeds of
the population to the average day that the plants of the population
produce at least one cotton boll that contains a seed, wherein the
seed comprises at least one embryo with a cotyledon in the
primordia stage and optionally wherein the seed comprises a black
layer (restricted growth media volume). In certain aspects, the
stressed condition comprises growing the population of cotton plant
at a temperature of at least about 37.degree. C., 38.degree. C.,
39.degree. C., 40.degree. C., 41.degree. C., 42.degree. C.,
43.degree. C., 44.degree. C., 45.degree. C., 46.degree. C.,
47.degree. C., or 48.degree. C. for at least about 2, 3, 4, 5, 6,
7, 8, 9, 10, 11, or 12 hours per day, for at least 40 days, for at
least 50 days, for at least 60 days, for at least 70 days, for at
least 75 days, or for at least 80 days during the time from the
average day of germination of the cotton seeds of the population to
the average day that the plants of the population produce at least
one cotton boll that contains a seed, wherein the seed comprises at
least one embryo with a cotyledon in the primordia stage and
optionally wherein the seed comprises a black layer (high
temperature). In certain aspects, the stressed condition comprises
growing the population of cotton plants by providing the cotton
plants of the population on average with less than about 500 mL,
less than about 400 mL, less than about 300 mL, less than about 200
mL, less than about 100 mL, or less than about 50 mL of water per
day on average, for at least 40 days, for at least 50 days, for at
least 60 days, for at least 70 days, for at least 75 days, or for
at least 80 days during the time from the average day of
germination of the cotton seeds of the population germinates to the
average day that the plants of the population produce at least one
cotton boll that contains a seed, wherein the seed comprises at
least one embryo with a cotyledon in the primordia stage and
optionally wherein the seed comprises a black layer (restricted
irrigation). In certain aspects, the stressed condition can be a
combination of any of these.
[0020] In certain aspects, at least about 50%, 60%, 70%, 80%, 90%,
or 95% of the plants in the population produce seed. In certain
aspects, at least one cotton plant of the population, having
produced at least one cotton boll that contains a seed, wherein the
seed comprises at least one embryo with a cotyledon in the
primordia stage and optionally wherein the seed comprises a black
layer, is of a diminished size, such as decreased in height and/or
having reduced biomass, compared to a control plant. In certain
aspects, at least about 50%, 60%, 70%, 80%, 90%, or 95% of the
plants in the population, having produced at least one cotton boll
that contains a seed, wherein the seed comprises at least one
embryo with a cotyledon in the primordia stage and optionally
wherein the seed comprises a black layer, are of a diminished size,
such as decreased in height and/or having reduced biomass, compared
to a control plant.
[0021] In certain aspects, the population is grown in a controlled
environment.
[0022] In certain aspects, at least about 50%, 60%, 70%, 80%, 90%,
95%, 98%, or 99% of the plants in the population have produced at
least one cotton boll that contains a seed, wherein the seed
comprises at least one embryo with a cotyledon in the primordia
stage and optionally wherein the seed comprises a black layer, and
are less than about 30 inches tall, less than about 24 inches tall,
less than about 18 inches tall, less than about 15 inches tall, or
less than about 12 inches tall. In certain aspects, at least about
50%, 60%, 70%, 80%, 90%, 95%, 98%, or 99% of the plants in the
population have at least 20 seeds, at least 30 seeds, at least 40
seeds, at least 50 seeds, or at least 60 seeds.
[0023] In certain aspects, at least one plant from the population
of plants grown under a stressed condition is used in a breeding
program. In certain aspects, the method further comprises
collecting at least one seed from at least one plant from the
population of plants grown under a stressed condition. In certain
aspects, the method further comprises testing (e.g., genotyping
and/or phenotyping) at least one collected seed or plant grown from
the collected seed. In certain aspects, the method further
comprises growing and/or crossing a cotton plant based on the
testing.
[0024] In certain aspects, the population of cotton plants is grown
at an average density of at least 10, 30, 60, 75, 100, 125, or 150
plants per square meter. In certain aspects, the population of
plants comprises at least about 50 cotton plants, at least about
100 cotton plants, at least about 500 cotton plants, at least about
1,000 cotton plants, at least about 5,000 cotton plants, at least
about 10,000 cotton plants, at least about 100,000 cotton plants,
at least about 500,000 cotton plants, at least about 1,000,000
cotton plants. Similarly, in certain aspects, the population of
plants comprises 50 or more cotton plants, 100 or more cotton
plants, 500 or more cotton plants, 1,000 or more cotton plants,
5,000 or more cotton plants, 10,000 or more cotton plants, 100,000
or more cotton plants, 500,000 or more cotton plants, or 1,000,000
or more cotton plants. In certain aspects, the population of cotton
plants is grown under a stressed condition at an average density of
at least 10, 30, 60, 75, 100, 125, or 150 plants per square meter,
for at least 40 days, for at least 50 days, for at least 60 days,
for at least 70 days, or for at least 80 days during the time from
the average day of germination of the cotton seeds of the
population germinates to the average day that the plants of the
population produce at least one cotton boll that contains a seed,
wherein the seed comprises at least one embryo with a cotyledon in
the primordia stage and optionally wherein the seed comprises a
black layer.
[0025] Provided herein are populations of cotton plants with an
altered morphology. It is understood that reference to "an aspect"
refers to any of the populations of plants disclosed herein and
should not be limited to any particular population unless otherwise
stated. In certain aspects, the population of plants is grown at a
density of at least 30, 60, 65, 75, 100, 125, or 150 plants per
square meter. In certain aspects, at least about 30%, 40%, 50%,
60%, 70%, 80%, 90%, 95%, 98%, or 99% of the plants in the
population have reached a stage in their life cycle when pinhead
squares have formed. In certain aspects, at least about 75%, 80%,
85%, 90%, 95%, 98%, or 99% of the plants in the population produce
at least one cotton boll that contains a seed, wherein the seed
comprises at least one embryo with a cotyledon in the primordia
stage and optionally wherein the seed comprises a black layer. In
certain aspects, at least about 75%, 80%, 85%, 90%, 95%, 98%, or
99% of the plants in the population produce at least 20 seeds, at
least 30 seeds, at least 40 seeds, at least 50 seeds, or at least
60 seeds. In certain aspects, at least about 75%, 80%, 85%, 90%,
95%, 98%, or 99% of the plants in the population are less than
about 30 inches tall, less than about 24 inches tall, less than
about 18 inches tall, less than about 15 inches tall, or less than
about 12 inches tall. In certain aspects, the average height of the
population is less than about 30 inches tall, less than about 24
inches tall, less than about 18 inches tall, less than about 15
inches tall, or less than about 12 inches tall. In certain aspects,
the population of plants comprises at least about 50 cotton plants,
at least about 100 cotton plants, at least about 500 cotton plants,
at least about 1,000 cotton plants, at least about 5,000 cotton
plants, at least about 10,000 cotton plants, at least about 100,000
cotton plants, at least about 500,000 cotton plants, at least about
1,000,000 cotton plants. Similarly, in certain aspects, the
population of plants comprises 50 or more cotton plants, 100 or
more cotton plants, 500 or more cotton plants, 1,000 or more cotton
plants, 5,000 or more cotton plants, 10,000 or more cotton plants,
100,000 or more cotton plants, 500,000 or more cotton plants, or
1,000,000 or more cotton plants.
[0026] In certain aspects, the population of plants is grown
according to any of the aforementioned methods. In certain aspects,
the population of plants is grown in a controlled environment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 shows two different cotton plants with cotton bolls
(seeds) and an altered morphology. The cotton plants were grown in
approximately 380 mL of soil and have a reduced stature, as evident
in relationship to the hand holding it (left) and measuring tape
showing 12 inches (right).
[0028] FIG. 2 shows cotton plants with reduced stature in
comparison to plants of normal height.
[0029] FIG. 3 shows cotton plants of reduced stature with bolls,
grown at high density in a tray (top), in comparison to large,
field grown plants (bottom).
[0030] FIG. 4 illustrates examples of a time period, e.g. "at least
40 days," "at least 60 days," and "at least 80 days," during the
time from when the cotton seed germinates to when the cotton plant
produces at least one cotton boll that contains a seed as described
in detail herein. Consecutive as well as non-consecutive days are
exemplified.
[0031] FIG. 5 shows distribution of flowering time as days after
planting (DAP) in a population of cotton plants for several cotton
lines.
[0032] FIG. 6 shows the results disclosed in FIG. 5 as the
cumulative % of plants that have flowered at DAP.
DETAILED DESCRIPTION
[0033] Provided herein are methods of cultivating plants, such as
crop plants, to produce reproductively-viable (e.g.,
seed-producing) plants yet with altered morphologies amendable for
growth at high density and/or use in breeding programs, and in
particular for growth under controlled conditions, e.g., in a
controlled environment. In certain aspects, the altered morphology
is a miniaturized plant such as a plant having a reduced stature,
decrease in height, shortened internode length, reduced biomass,
and the like. Such plants can be grown at higher densities and thus
require less space for a given number of plants. This in turn makes
it more feasible to grow a population of plants under cover (i.e.,
generally protected from pollinating insects), which in turn can
increase the genetic purity of crosses achieved in a breeding
program, making the breeding program more efficient and/or cost
effective. Thus, in certain aspects, the methods are performed for
the purpose of improving the efficiency breeding programs. Further,
it has been discovered populations of plants grown under stressed
conditions disclosed herein can display tighter synchronization in
their development time, such as flowering and/or seed production,
which also can improve the efficiency breeding programs.
[0034] Methods include subjecting plants to one or more stressed
conditions and/or application of certain plant growth regulators
(PRGs). Further provided are seed producing plants with altered
morphologies compared to corresponding control plants.
[0035] While in certain aspects, a plant grown under the conditions
of stress and/or application of a PGR disclosed herein produces
seed, the number of seed need not be as many as a plant grown under
normal conditions or wanted for commercial sale. For example, in a
plant breeding program, only a certain number of seeds may be
needed for screening and replanting, and thus any seeds in excess
of that amount are unnecessary. The purpose of breeding programs is
to cross plants and recover seeds from those crosses in order to
capture and analyze the genetics of the seeds and/or to recover the
seed so that that resulting plant and its genetics can be used in
future crosses. The more efficiently that this process can be done,
the more quickly new lines of plants can be developed and/or the
lower the costs of development. It is currently thought that the
most efficient way to grow plants in a breeding program is to grow
plants in a manner that maximizes health and growth, e.g., that
mimic commercial planting conditions. However, the number of seeds
required for use in a breeding program may be less than the amount
of seed typically produced by commercial growers attempting to
maximize cotton fiber yield. In fact, producing extra seeds at
certain steps of a breeding program could be considered waste.
Thus, it may be acceptable at certain steps of a breeding program
to grow plants that produce a fewer number of seeds than their
genetic potential when grown under optimal or commercial planting
conditions.
Definitions
[0036] To the extent necessary to provide descriptive support, the
subject matter and/or text of the appended claims is incorporated
herein by reference in their entirety.
[0037] It will be understood by all readers of this written
description that the exemplary embodiments described and claimed
herein may be suitably practiced in the absence of any recited
feature, element or step that is, or is not, specifically disclosed
herein.
[0038] It is to be noted that the term "a" or "an" entity refers to
one or more of that entity; for example, "a plant," is understood
to represent one or more plants. As such, the terms "a" (or "an"),
"one or more," and "at least one" can be used interchangeably
herein. The phrase "one or more" as used herein is interchangeable
with "at least one."
[0039] Furthermore, "and/or" where used herein is to be taken as
specific disclosure of each of the two specified features or
components with or without the other. Thus, the term and/or" as
used in a phrase such as "A and/or B" herein is intended to include
"A and B," "A or B," "A" (alone), and "B" (alone). Likewise, the
term "and/or" as used in a phrase such as "A, B, and/or C" is
intended to encompass each of the following embodiments: A, B, and
C; A, B, or C; A or C; A or B; B or C; A and C; A and B; B and C; A
(alone); B (alone); and C (alone).
[0040] It is understood that wherever aspects are described herein
with the language "comprising," otherwise analogous aspects
described in terms of "consisting of" and/or "consisting
essentially of" are also provided.
[0041] Unless defined otherwise, technical and scientific terms
used herein have the same meaning as commonly understood by one of
ordinary skill in the art to which this disclosure is related.
Numeric ranges are inclusive of the numbers defining the range.
Even when not explicitly identified by "and any range in between,"
or the like, where a list of values is recited, e.g., 1, 2, 3, or
4, the disclosure specifically includes any range in between the
values, e.g., 1 to 3, 1 to 4, 2 to 4, etc.
[0042] The headings provided herein are solely for ease of
reference and are not limitations of the various aspects or aspects
of the disclosure, which can be had by reference to the
specification as a whole. Accordingly, the terms defined
immediately below are more fully defined by reference to the
specification in its entirety.
[0043] A used herein, a "plant" refers to a whole plant or any part
thereof. For example, for purposed of this disclosure, applying a
plant growth regulator to a "plant" includes applying the plant
growth regulator to a whole plant or any part thereof or plant part
(e.g., to the leaves, stems, roots, seeds, etc.).
[0044] As used herein, a "population of plants," "plant
population," or the like refers to at least two or more plants.
Most commonly, the terms relate to a breeding population of plants
from which members are selected and crossed to produce progeny in a
breeding program. A population of plants can include the progeny of
a single breeding cross or a plurality of breeding crosses, and can
be either actual plants or plant derived material, or in silico
representations of the plants. The population members need not be
identical to the population members selected for use in subsequent
cycles of analyses or those ultimately selected to obtain final
progeny plants. Often, a plant population is derived from a single
biparental cross, but may also derive from two or more crosses
between the same or different parents. Although a population of
plants may comprise a small plurality of individuals, those of
skill in the art will recognize that plant breeders commonly use
population sizes ranging from one or two hundred individuals to
several thousand, and that the highest performing 5-20% of a
population is what is commonly selected to be used in subsequent
crosses in order to improve the performance of subsequent
generations of the population.
[0045] As used herein, the term "non-naturally occurring"
condition, substance, composition, entity, plant, organism,
individual, and/or any combination thereof, or any grammatical
variants thereof, is a conditional term that explicitly excludes,
but only excludes, those forms that are well-understood by persons
of ordinary skill in the art as being "naturally-occurring," or
that are, or might be at any time, determined or interpreted by a
judge or an administrative or judicial body to be,
"naturally-occurring."
[0046] As used herein, the terms "flower" and "inflorescence" are
used interchangeably.
[0047] The methods described herein are not limited to the process
by which a population of plants is brought together to be
cultivated. For example, it is commonly understood that seeds form
after fertilization and comprise a zygote or embryo surrounded by
tissues that were once part of the ovule. However, the term "seed"
as used herein can also have a more general meaning to include any
viable plant cell capable of undergoing cell division (e.g.
mitosis) to grow, and/or develop, and, in certain embodiments, form
reproductive structures. A seed can also be anything that can be
sown, or planted, directly into growth media including vegetative
structures, like potato tubers ("seed" potatoes), and/or sugarcane
stalks, and/or cells of a callus. A seed may also comprise a zygote
or embryo encased in some form of protective layer. In certain
embodiments the protective layer comprises tissues derived from
plant cells (e.g. cells of the maternal parent ovule), and a seed
may or may not include other tissues, for example, when the layers
of the seed protecting or enclosing the embryo are technically
considered to be part of a dried fruit or kernel, as they are in
corn and sunflower. Even artificial methods of coating or
protecting an embryo with a wide range of chemicals that serve at
least the purpose of protecting and/or sustaining, and or otherwise
supporting the embryo are envisioned. A seed could even be a naked
embryo, provided one was able to culture it into a vegetative or
flowing plant using one or more of the methods described herein.
One of skill will immediately appreciate that the methods disclosed
herein could be used in conjunction with any other process that
brings about a population of plants growing in a controlled
environment in the high densities and/or in at least one of the
stressed conditions described herein.
[0048] As used herein, the term "elite," "elite plant," and the
like describes a group, germplasm, or population of at least one
crop plant that has resulted from human-directed breeding and
selection for superior agronomic performance. An "elite population"
is an assortment of elite individuals or lines that can be used to
represent the state of the art in terms of agronomically superior
genotypes of a given crop species, such as cotton. Similarly, an
"elite germplasm" or "elite strain of germplasm" is an
agronomically superior germplasm, typically derived from and/or
capable of giving rise to a plant with superior agronomic
performance, such as an existing or newly developed elite line of
cotton. In contrast, an "exotic plant," "exotic line," or "exotic
germplasm" is a plant, line, or germplasm derived from a plant not
belonging to an available elite line or strain of germplasm. In the
context of a cross between two plants or lines of germplasm, an
exotic germplasm is not closely related by descent to the elite
germplasm with which it is crossed. Most commonly, the exotic
germplasm is not derived from any known elite line of a crop, but
rather is selected to introduce genetic elements (typically desired
alleles) into a breeding program.
[0049] As used herein, a "control" plant is a plant (or a member of
a population of plants) recognized as having a representative
phenotype (e.g., number of inflorescences, number of seeds, height,
internode length, biomass, and the like), of a plant grown under
normally recommended growing conditions, but that is in other
respects, such as genetic makeup, comparable to a plant grown under
a stressed condition. For example, one of ordinary skill in the art
would understand a control plant to have one or more of the
following attributes: results from a seed derived from the same
haploid induction cross; has at least one parent in common with the
treated plant; shares a common ancestor with the treated plant
within twelve generations; shares sufficient common genetic
heritage with the treated plant that one of ordinary skill in the
art of plant breeding would recognize the control plant as a valid
comparison for establishing a correlation between the stressed
growth condition and the resulting phenotype; and/or achieves a
morphology considered typical of the mature plant. One of ordinary
skill in the art will recognize that a control plant that by chance
(e.g., a statistical outlier), by some other type of manipulation,
or other reason comprises a phenotype that varies from a
representative phenotype of control plants would not be an
appropriate control plant for comparison.
[0050] As used herein, the term "grown in a controlled
environment," means that a plant or population of plants is grown
in an enclosure capable of excluding pollinating insects. Such
enclosures include screened in enclosures such as cages, green
houses, hothouses, grow houses, hoop houses, warehouses, and growth
chambers. It is understood that "capable of excluding pollinating
insects," does not mean that all pollinating insects are absolutely
excluded, but that fewer pollinating insects have access to the
plant or population of plants than if the plant or population of
plants was not grown in a controlled environment. Growth in a
controlled environment may also include control over one or more
additional factors such as lighting, temperature, humidity,
irrigation, growth media volume, protection from the elements such
as wind and hail, exclusion of windborne pollen, and protection
from windblown pesticide contamination.
[0051] A plant "growth media" as referred to herein can be any type
of substance suitable for growing plants. Commonly, soil is used as
a growth media for growing plants.
[0052] A flower bud of a cotton plant can be referred to as a
"square". It generally comprises a central corolla containing
re-productive structures (e.g. anthers) and sepals and surrounded
by three (or sometimes four) bracts. Several morphological stages
of square development (i.e. "squaring") are recognized by cotton
growers. The "pinhead" square stage begins when the square first
becomes identifiable to the naked eye and it is followed by the
"match-head" or "one-third grown" square. Later, the bud takes on a
candle shape, typically just before blooming.
[0053] Stressed Conditions
[0054] Disclosed herein are methods including growing plants,
producing seeds, and conducting plant breeding, and the like, in
which certain stresses are applied to the plants. These stressed
conditions deviate from the established conditions recommended for
commercial production or conditions that would likely be tested in
research programs aimed at optimizing growth conditions for maximum
plant health and yield. In certain aspects, one or more of these
stressed conditions is the result of human control and/or
manipulation of the growing conditions ("controlled conditions,"
e.g., in a "controlled environment") and vary from conditions that
may naturally be experienced by plants grown in the field. That is,
even though plants in the field may experience conditions of e.g.,
drought and/or high temperatures due to natural weather conditions,
certain aspects of the methods disclosed herein are distinguishable
from those conditions because the conditions are being controlled
and/or manipulated by humans, such as within an enclosure or by
planting in a restricted amount of growth medium and/or growing
plants to maturity at high density.
[0055] In certain aspects, a method involves growing a plant from a
seed. In certain aspects, application of one or more stressed
conditions results in an altered plant morphology compared to a
control plant. In certain aspects, one or more of these stressed
conditions can be applied from when the seed is sown and/or
germinated and maintained throughout all or a portion of the period
during which a plant is grown. Further in certain aspects, a plant
with an altered morphology and despite the stressed conditions,
still produces at least some seed that can be used, for example, in
a breeding program.
[0056] While the details of different stressed conditions are
described separately below, it is understood that methods herein
can comprise any one, any combination of, or all of the stressed
conditions. Further, while the stressed conditions may be described
as applied to a plant, it is understood that any of such stressed
condition or combination of stressed conditions can be applied to a
population of plants.
[0057] Restricted Growth Media Volume
[0058] In certain aspects, the stressed condition applied to a
plant is growing the plant in a restricted volume of growth media
that is reduced, in some instances significantly from the generally
recommended amount, to achieve altered plant morphologies. In
certain aspects, plants grown under restricted soil volume stress
(or a combination of soil volume stress with other types of
stressed conditions and/or the application of plant growth
regulators) resulting in altered morphologies still produce at
least some seed.
[0059] Cotton plants, for example, are commonly grown spaced apart
in open fields or if in containers, in containers with at least
about 3 L of soil volume, e.g., 3 L buckets or bags, to allow them
what is generally considered sufficient room for healthy growth. In
contrast, in certain aspects of the methods herein, a restricted
soil volume is less than about 2,000 mL, less than about 1,500 mL,
less than about 1,000 mL, less than about 900 mL, less than about
800 mL, less than about 700 mL, less than about 600 mL, less than
about 500 ml, less than about 450 mL, less than about 400 mL, less
than about 350 mL, less than about 300 mL, less than about 250 mL,
or less than about 200 mL of soil volume. In certain aspects, a
restricted soil volume is from any of about 100 mL, 200 mL, 300 mL,
400 mL, 450 mL, 500 mL, or 1,000 mL of soil volume to any of about
300 mL, 400 mL, 450 mL, 500 mL, 600 mL, 700 mL, 800 mL, 900 mL,
1,000 mL, 1,500 mL, or 2,000 mL of soil volume. For example, from
about 200 mL to about 500 mL, from about 250 mL to about 450 mL,
from about 300 mL to about 500 mL, or from about 350 mL to about
450 mL of soil volume.
[0060] It is understood that the amount of soil that a plant is
grown in can be restricted by growing the plant in a container. In
certain aspects, one plant is grown per container. More than one
plant, however, can be grown in a shared container. In such cases,
the amount of soil volume per plant can be considered the amount of
soil volume in the container divided by the number of plants in the
container.
[0061] It may be common practice to sow a seed in a small volume of
soil and then replant the plant into a larger container containing
more soil, or even a series of successively larger containers, as
the plant grows and becomes larger. If the plant is replanted as it
grows into an amount of soil that does not create stress, it will
not achieve the morphologies described herein. In contrast, in the
methods disclosed herein, a plant is grown in a restricted soil
volume for a defined period of time so that the plant is stressed
as it grows. In certain aspects, a cotton plant is grown in a
restricted soil volume for at least 40 days, at least 50 days, at
least 60 days, at least 70 days, at least 75 days, at least 80
days, or at least 85 days during the time from when the seed
germinates to when the plant produces at least one cotton boll that
contains a seed, wherein the cotton seed comprises at least one
embryo with a cotyledon in the primordia stage. In certain aspects,
the cotton seed comprises a black layer. Under permissive
conditions for germination, a cotton seed, for example, will
germinate generally around 12 hours to 48 hours after being sown.
Similarly, in certain aspects, a non-cotton plant is grown in a
restricted soil volume for a corresponding percentage of days
during the time from when the seed germinates until when the plant
reaches its reproductive stage. The number of days during which the
plant is grown under the stressed condition need not be
consecutive, i.e., the number of days in the restricted soil volume
is the cumulative number of days from when the seed is sown or
germinates to when the plant reaches reproductive stage. In certain
aspects, the period of time is in consecutive days.
[0062] Cultivation at High Temperatures
[0063] In certain aspects, plants are stressed by cultivation at
high temperatures. Without being bound by theory, it is suggested
in the art that temperatures above about 35.degree. C. can hamper
photosynthesis and additionally, plant development and survival. In
certain aspects, cultivation at high temperatures is combined with
the aforementioned methods of growing plants in restricted soil
volumes and/or with the below mentioned methods of growing plants
with restricted irrigation. In certain aspects, the temperatures
are at least about 5.degree. C. higher than what would normally be
recommended as the highest temperature at which to grow the
plant.
[0064] It has been discovered that growing a plant at daily high
temperatures in the range of about 37.degree. C. to about
48.degree. C., even for just a few hours a day, can result in
altered plant morphologies. In certain aspects, plants that are
grown under high temperature stress (or a combination of high water
stress with other types of stressed conditions and/or the
application of plant growth regulators) resulting in altered
morphologies still produce at least some seed.
[0065] In certain aspects, a plant is grown at a temperature of at
least about 37.degree. C., 38.degree. C., 39.degree. C., 40.degree.
C., 41.degree. C., 42.degree. C., 43.degree. C., 44.degree. C.,
45.degree. C., 46.degree. C., 47.degree. C., or 48.degree. C. In
certain aspects, the duration of time per day during which a plant
is grown at the temperature can be as little as 2 hours, or at
least about 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8
hours, 9 hours, 10 hours, 11 hours, or 12 hours per day. The
duration of time per day during which a plant is exposed to the
above temperatures can be consecutive and/or cumulative over the
course of a day, including non-daylight hours. Generally, however,
the temperature rises during the day and then decreases overnight.
In certain aspects, plants are grown at cooler temperatures
overnight, such as at least 5.degree. C., 10.degree. C., 15.degree.
C., 20.degree. C., or 25.degree. C. cooler than the maximum daytime
temperature. In certain aspects, the average nighttime temperature
is from about 18.degree. C. to about 22.degree. C. In certain
aspects, a cotton plant is grown at these high temperatures and
times for at least 40 days, at least 50 days, at least 60 days, at
least 70 days, at least 75 days, at least 80 days, or at least 85
days during the time from when the seed germinates to when the
plant produces at least one cotton boll that contains a seed,
wherein the cotton seed comprises at least one embryo with a
cotyledon in the primordia stage. In certain aspects, the cotton
seed comprises a black layer. Similarly, in certain aspects, a
non-cotton plant is grown at these high temperatures and times for
a corresponding percentage of days during the time from when the
seed germinates until when the plant reaches its reproductive
stage. The number of days during which the plant is grown under the
stressed condition need not be consecutive, i.e., the number of
days the plant is grown at a high temperature is the cumulative
number of days from when the seed is sown or germinates to when the
plant reaches reproductive stage. For example, a plant can be grown
at a high temperature for a few days, then at a lower temperature
for a day or more, and then back to being grown at a high
temperature, and so forth. In certain aspects, the period of time
is in consecutive days.
[0066] In certain aspects, the duration of time that a plant is
subjected to high heat is limited to prevent overstressing the
plant to a point that it will not produce seeds. Thus, in certain
aspects, on at least about 50%, 60%, 70%, 80%, 90%, 95%, 98%, or
100% of the days on which the plant is grown at a temperature of at
least about 37.degree. C., 38.degree. C., 39.degree. C., 40.degree.
C., 41.degree. C., 42.degree. C., 43.degree. C., 44.degree. C., or
45.degree. C., it is not grown at this temperature for more than
about 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16, 18, or 20 hours
per day, i.e., grown below this temperature for at least 4, 6, 8,
9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 hours per day. In certain
aspects, on at least about 50%, 60%, 70%, 80%, 90%, 95%, 98%, or
100% of the days on which the plant is grown at a temperature of at
least about 37.degree. C., 38.degree. C., 39.degree. C., 40.degree.
C., 41.degree. C., 42.degree. C., 43.degree. C., 44.degree. C., or
45.degree. C., the plant is also grown at a temperature of about
18.degree. C. to 22.degree. C. for at least 2, 3, 4, 5, 6, 7, 8, 9,
10, 11, 12, 13, 14, 15, or 16 hours per a day.
[0067] A combination of stressed conditions may produce an additive
effect in which the severity of an individual stressed condition
may be reduced but still achieve a plant with a desired altered
morphology. In certain aspects, when a plant is grown under
restricted growth media volume and/or restricted irrigation
stressed conditions as described elsewhere herein, the high
temperature stressed condition can be reduced to at least about
32.degree. C., 33.degree. C., 34.degree. C., 35.degree. C., or
36.degree. C., under the conditions of hours per day, days between
germination and seed formation, etc., otherwise described
herein.
[0068] As described anywhere herein unless otherwise stated, while
the days between germination and seed formation, reaching
reproductive stage, and the like during which various stressed
conditions are applied will generally overlap, it is not necessary
that they correspond or even overlap. For example, a plant could be
subjected to limited irrigation on one day at a normal temperature
and then given a normal amount of water the next day but subjected
to high temperatures. For example, a plant may be grown in a
restricted soil volume for a period of time under normal water and
temperature conditions, and then replanted in a normal soil volume
but subjected to temperature and/or irrigation stress.
[0069] Restricted Irrigation
[0070] In certain aspects, plants are stressed by restricting the
amount of water that they receive. In certain aspects, water
restriction is combined with the aforementioned methods of growing
plants in restricted soil volumes and/or high temperatures. For
example, whereas generally recommended irrigation of a plant may be
about 500 mL to about 1,000 mL of water per 24 hour period for most
growing days, in certain aspects, a plant is provided with about
1/10.sup.th or less water, such as less than about 100 mL of water,
during the same period of time. In certain aspects, plants are
grown under water restriction (or a combination of restricted
irrigation stress with other types of stressed conditions and/or
the application of plant growth regulators) resulting in altered
morphologies still produce at least some seed.
[0071] In certain aspects, the amount of restricted water is not
determined as a daily basis, but rather the average amount of water
per day over a given number of days. For example, a plant that is
watered with 600 mL on a first day and then not watered the next
two consecutive days would on average have been water with 200 mL
of water per day during the three day period.
[0072] In certain aspects, a plant is provided with less than about
500 mL, less than about 400 mL, less than about 300 mL, less than
about 200 mL, less than about 100 mL, or less than about 50 mL of
water per day on average. In certain aspects, a plant is provide
with any of about 1 mL, 10 mL, 25 mL, 50 mL, 100 mL, 200 mL, 250
mL, or 300 mL of water per day on average, to any of about 50 mL,
100 mL, 200 mL, 250 mL, 300 mL, 400 mL, or 500 mL of water per day
on average. In certain aspects, a cotton plant is grown under any
of these restricted irrigation conditions for at least 40 days, at
least 50 days, at least 60 days, at least 70 days, at least 75
days, at least 80 days, or at least 85 days during the time from
when the seed germinates to when the plant produces at least one
cotton boll that contains a seed, wherein the cotton seed comprises
at least one embryo with a cotyledon in the primordia stage. In
certain aspects, the cotton seed comprises a black layer.
Similarly, in certain aspects, a non-cotton plant is grown under
restricted irrigation conditions for a corresponding percentage of
days during the time from when the seed germinates until when the
plant reaches its reproductive stage.
[0073] Plant Growth Regulators (PGRs)
[0074] Certain aspects provide for the use of plant growth
regulators (PGRs) to induce altered plant morphologies, either by
the use of PGRs alone or in combination with one or more of the
aforementioned stressed conditions to achieve an altered
morphology. In certain aspects, plants treated with a PGR (or a
combination of PGR with one or more aforementioned stresses)
resulting in altered morphologies still produce at least some
seed.
[0075] In certain aspects provided herein, a plant can be contacted
with a wide variety of PGRs. PGRs are a class of compounds that
affect the cellular processes, growth, development or behavior of a
plant. PGR can be responsible for accelerating or retarding the
rate of growth or maturation or otherwise altering the behavior of
a plant. In some aspects, a PGR is a naturally-occurring plant
hormone capable of altering flower development, internode length,
apical dominance, ripening, root architecture, fruiting and/or
other characteristics of a plant. In some aspects, a PGR is a
chemical capable of altering flower development, internode length,
apical dominance, ripening, root architecture, fruiting and/or
other characteristics of a plant. Plant growth regulators include
auxins (e.g. IAA) and auxin inhibitors, cytokinins (e.g. BAP) and
cytokinin inhibitors, compounds that can stimulate ethylene
production (i.e. ACC and the like) and compounds that can inhibit
ethylene production (AVG and the like), and compounds that inhibit
ethylene perception (silver and the like). Plant growth regulators
also comprise compounds that modulate plant perception, signaling,
and/or behavior, such as giberrellins and their inhibitors (e.g.
Paclobutrazol (PBZ) or uniconazole), abscisic acid and its
inhibitors, and jasmonic acid and its inhibitors. In certain
aspects, the plant growth regulator is a plant hormone, gibberellic
acid inhibitor, cytokinin, or any combination thereof.
[0076] In certain aspects, a PGR is an exogenously-provided
compound that can be introduced to the surface of a plant and
migrate into a plant tissue. In some aspects, the PGR acts
extracellularly within the plant tissue, such as interacting with
receptors on the outer cell surface. In some aspects, the PGR
enters into cells within the tissue. In some aspects, the PGR is
contained within a liquid. Such liquids include, but are not
limited to aqueous and non-aqueous solutions, suspensions,
emulsions, and colloidal dispersions. A "plant treatment solution"
or "treatment solution" can refer to any solution of liquid that
comprises a PGR.
[0077] In certain aspects, contact between the plant and the
treatment agent is achieved by dipping, submerging, or otherwise
inserting the plant into a reservoir of liquid comprising the plant
treatment agent. Other methods of contacting a plant with a
treatment agent include spraying or misting the plant with a
solution comprising a plant treatment agent or agitating or
tumbling a plant in a solution comprising a plant treatment agent.
In certain aspects, contact between the plant and the treatment
agent is achieved by a soil drench, which comprises adding a liquid
treatment agent to the soil or growth medium near the plant
roots.
[0078] In certain aspects, liquids are of an aqueous nature. In
certain aspects, aqueous liquids can comprise water soluble
components. In certain aspects, aqueous liquids can comprise water
insoluble components, can comprise an insoluble component that is
made soluble in water by addition of a surfactant, or can comprise
any combination of soluble components, insoluble components, and
surfactants.
[0079] In certain aspects, the PGR can be any compound known to
inhibit the synthesis, uptake, or persistence of gibberellic acid
in a plant. For example, one non-limiting example of a PGR that can
be used with this invention is selected from the group comprising
chlormequat-CL, mepiquat-CL, AMO-1618, clorphonium-Cl, tetcylacis,
ancymidol, flurprimidol, paclobutrazol, uniconazole-P, inabenfide,
prohexadione-CA, trinexapac-ethyl, daminozide, exo-16,17-, and
dihydro-GA5-13-acetate. Other examples include peptide hormones,
for example, systemin, phytosulfokine, rapid alkalinization factor.
In certain aspects, the PGR is mepiquat chloride.
[0080] IAA is indole-3-acetic acid, and IBA is inodole-3-butyric
acid. Both are naturally-occurring forms of a class of plant
hormones called auxins. Other variations of auxin can be used,
including synthetic auxins, such as 2,4-D (2,4-Dichlorophenoxyactic
acid and .quadrature.-NAA (.quadrature.-Naphthalene acetic
acid).
[0081] As used herein, PBZ is paclobutrazol,
(2S,3S)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-1-yl)
pentan-3-ol, also written as C15H1OCIN30, a plant growth regulator
and triazole fungicide. It is a known antagonist of the plant
hormone gibberellins that inhibits giberellin biosynthesis,
reducing internodal growth and increasing stem girth. BAP is
6-Benzylaminopurine, N-(Phenylmethyl)-7H-pruin-6-amine, also
written as C12H11N5. IAA is indole-3-acetic acid, and IBA is
inodole-3-butyric acid. Both are naturally-occurring forms of a
class of plant hormones called auxins. Other variations of auxin
can be used with this invention, including synthetic auxins, such
as 2,4-D (2,4-Dichlorophenoxyactic acid) and 1-NAA (1-Naphthalene
acetic acid).
[0082] As used herein, uniconazole is
(e)-(+/-)-beta-((4-chlorophenyl)methylene)-alpha-(1,1-dimethylethyl)-1h-1-
,2,4-triazole-1-ethanol, also written as C15H18CIN3O, also known as
uniconazole-P. It is a triazole-type plant growth retardant and
known antagonist of the plant hormone giberellin that reduces
internodal growth and increases stem girth.
[0083] As used herein, mepiquat chloride is also known as
N,N-dimethylpiperidinium chloride, C7H16CIN, PIX.RTM.,
mepiquat-CL.
[0084] In general, PGRs used herein will be water soluble agents.
However, the use of PGRs with high, intermediate, low or negligible
water solubility can, in certain aspects, be facilitated by the use
of liquid compositions that also comprise various transfer or
conditioning agents. Transfer or conditioning agents can comprise
any agent that facilitates migration of plant treatment agents to
the plant (e.g., plant cells) and/or that facilitate uptake of
plant treatment agents by the plant. Transfer or conditioning
agents include, but are not limited to, (a) surfactants, (b) an
organic solvents or an aqueous solutions or aqueous mixtures of
organic solvents, (c) oxidizing agents, (d) acids, (e) bases, (f)
oils, (g) enzymes, or combinations thereof. In certain aspects,
methods can optionally include an incubation step, a neutralization
step (e. g., to neutralize an acid, base, or oxidizing agent, or to
inactivate an enzyme), a rinsing step, or combinations thereof
whereby the liquid and plant treatment agent contained therein is
treated either before or after delivery to the plant. Transfer or
conditioning agents thus include, but are not limited to,
emulsions, reverse emulsions, liposomes, and other micellar-like
compositions. Examples of useful adjuvants include surfactants and
effective molecules contained therein, which include sodium or
lithium salts of fatty acids (such as tallow or tallowamines or
phospholipids). Transfer or conditioning agents can comprise salts
including, but not limited to, sodium, ammonium, calcium, lithium,
magnesium, chloride, sulfide, and sulfate salts. Certain aspects of
the methods provided herein use counter-ions or other molecules
that are known to associate with plant treatment agents. For
certain negatively charged plant treatment agents such as
polynucleotides, cations such as inorganic ammonium ions, alkyl
ammonium ions, lithium ions, polyamines such as spermine,
spermidine, or putrescine, and the like can be used. Organic
solvents useful in conditioning a plant cell to permeation with
certain plant treatment agents including, but not limited to
polynucleotides, are solvents such as DMSO, DMF, pyridine,
N-pyrrolidine, hexamethyiphosphoramide, acetonitrile, dioxane,
polypropylene glycol, or other solvents that are miscible with
water. Naturally derived or synthetic oils with or without
surfactants or emulsifiers can be used, e. g., plant-sourced oils,
crop oils (such as those listed in the 9th Compendium of Herbicide
Adjuvants, publicly available on the world wide web (internet) at
"herbicide.adjuvants.com") can be used. Oils useful in certain
liquid compositions used in the methods provided herein include,
but are not limited to, paraffinic oils, polyol fatty acid esters,
or oils with short-chain molecules modified with amides or
polyamines such as polyethyleneimine or N-pyrrolidine.
[0085] In certain aspects of any of the methods herein, a plant is
contacted with the PGR by drenching, gassing, injecting, or
spraying.
[0086] In certain aspects, a broad range of chemical concentrations
can be used in conjunction with these methods and one of ordinary
skill in the art can optimize the dose administered to a given
plant subjected to any of the stressed conditions disclosed herein
in order to maximize a desired morphology.
[0087] In certain aspects, the use of the PGR is inconsistent with
prior methods of applying the PGR. For example, it is expressly
recommended by the manufacturer that a user should not apply
mepiquat chloride until after pinhead squares have formed on the
plant (typically 25-30 days after planting (DAP)). In certain
aspects, however, the method comprises applying the PGR before the
first pinhead square stage. In certain aspects, the method
comprises applying the PGR at a day not past 20 days, 21 days, 22
days, 23 days, or 25 days after germination. In certain aspects,
the method comprises applying a PGR at 20 to 25 days after
germination, 20 to 24 days after germination, 21 to 23 days after
germination, or 22 to 24 days after germination.
[0088] Altered Plant Morphologies
[0089] Provided herein are plants with altered morphologies due to
the application of one or more stressed conditions and/or
application of a PGR while the plant is growing. That is, a plant
with an altered morphology disclosed herein grown according to any
of the aforementioned methods. In particular, the aforementioned
growing conditions result in plants that typically have a reduced
height, shorter internode lengths, and/or decreased biomass than
plants grown under normal or recommended growing conditions. While
the growth of these plants may appear sickly or stunted to one of
ordinary skill in the art, it has been discovered that under the
right conditions, such plants can produce at least some seeds and
thus can be useful, for example, in plant breeding programs. In
certain aspects, a plant is grown in a controlled environment, for
example, to protect it pollinating insects.
[0090] In certain aspects, the height of a cotton plant is measured
from the cotyledon to the topmost structure of the plant. As used
herein for a cotton plant, measuring to the topmost structure of
the cotton plant (also referred to herein as "top of the plant")
means measuring to the uppermost node that is associated with an
unfurled leaf at least 1 inch in diameter. One of ordinary skill in
the art would recognize that there can be younger leaves higher up,
but that they are curled, and thus it is standard to ignore them
when measuring plant height in order ensure consistent
measurements.
[0091] On of ordinary skill in the art will recognize that
measuring from the cotyledon nodes is more consistent, but the
height of a plant can also be measured from the top of the soil
where the plant is growing to the topmost structure of the plant as
defined above. Without manipulation of the soil level intended to
obtain a pre-desired result, which is excluded from a height
measurement of this disclosure, one of ordinary skill in the art
would understand that the distance between the top of the soil and
the cotyledon nodes is about 2 to 6 inches (e.g., approximately 4
inches on average). Thus, one of ordinary skill in the art would
understand that if a measurement of plant height is taken from the
top of the soil to the top of the plant, that height can be
converted for comparison purposes to the heights disclosed herein
by subtracting 4 inches, i.e., that average distance between the
top of the soil and the cotyledon nodes. For example, if a plant is
measured from the top of the soil to the top of the plant and the
height is recorded as 26 inches, for purposes of this disclosure,
that plant's height is considered 22 inches.
[0092] In certain aspects, a plant is a plant having produced seed
but being less than about 30 inches tall, less than about 24 inches
tall, less than about 18 inches tall, less than about 15 inches
tall, or less than about 12 inches tall. In certain aspects, a
plant is a plant having produced seed but being from any of about 6
inches tall, 12 inches tall, 15 inches tall, 18 inches tall, or 24
inches tall to any of about 12 inches tall, 15 inches tall, 18
inches tall, 24 inches tall, or 30 inches tall (one of ordinary
skill in the art would understand how to convert inches into other
units such as centimeters or meters). While it is understood that a
plant growing from a seed will start out, for example, less than 12
inches tall, the growing plant during its vegetative stage will not
have produced seeds. By the time that a plant grown under normal
growth conditions reaches it reproductive stage and produces seed,
it will be taller than, for example, 12 inches tall.
[0093] In certain aspects, the plant is a cotton plant having
produced at least one cotton boll that contains a seed, wherein the
seed comprises at least one embryo with a cotyledon in the
primordia stage, but being less than about 30 inches tall, less
than about 24 inches tall, less than about 18 inches tall, less
than about 15 inches tall, or less than about 12 inches tall. In
certain aspects, the plant is a cotton plant having produced at
least one cotton boll that contains a seed, wherein the seed
comprises at least one embryo with a cotyledon in the primordia
stage, but being from any of about 6 inches tall, 12 inches tall,
15 inches tall, 18 inches tall, or 24 inches tall to any of about
12 inches tall, 15 inches tall, 18 inches tall, 24 inches tall, or
30 inches tall. While it is understood that a cotton plant growing
from a seed will start out, for example, less than 12 inches tall,
the growing cotton plant during its vegetative stage will not have
produced seeds. By the time that a cotton plant grown under normal
growth conditions produces at least one cotton boll that contains a
seed, it will be taller than, for example, 12 inches tall.
[0094] In certain aspects, a plant is less than about 30 inches
tall, less than about 24 inches tall, less than about 18 inches
tall, less than about 15 inches tall, or less than about 12 inches
tall but has at least 20 seeds, at least 30 seeds, at least 40
seeds, at least 50 seeds, or at least 60 seeds.
[0095] In certain aspects, the plant is a cotton plant that is less
than about 30 inches tall, less than about 24 inches tall, less
than about 18 inches tall, less than about 15 inches tall, or less
than about 12 inches tall but has at least 20 seeds, at least 30
seeds, at least 40 seeds, at least 50 seeds, or at least 60
seeds.
[0096] Certain aspects provide for growing a population of plants
comprising plants with an altered morphology, wherein the plants in
the population are grown according to the any of the methods
disclosed herein. In certain aspects, at least about 50%, 60%, 70%,
80%, 90%, 95%, 98%, or 99% of the plants in the population produce
seed. In certain aspects, at least one plant of the population is
of a reduced height compared to a control plant. In certain
aspects, at least about 50%, 60%, 70%, 80%, 90%, 95%, 98%, or 99%
of the plants in the population are of a reduced height compared to
a control plant. In certain aspects, the population is grown in a
controlled environment. In certain aspects, at least about 50%,
60%, 70%, 80%, 90%, or 95% of the plants in the population are less
than about 30 inches tall, less than about 24 inches tall, less
than about 18 inches tall, less than about 15 inches tall, or less
than about 12 inches tall. In certain aspects, at least about 50%,
60%, 70%, 80%, 90%, or 95% of the plants in the population are from
any of about 6 inches tall, 12 inches tall, 15 inches tall, 18
inches tall, or 24 inches tall to any of about 12 inches tall, 15
inches tall, 18 inches tall, 24 inches tall, or 30 inches tall. In
certain aspects, the average height of a plant in the population is
less than about 30 inches tall, less than about 24 inches tall,
less than about 18 inches tall, less than about 15 inches tall, or
less than about 12 inches tall. In certain aspects, the average
height of a plant in the population is from any of about 6 inches
tall, 12 inches tall, 15 inches tall, 18 inches tall, or 24 inches
tall to any of about 12 inches tall, 15 inches tall, 18 inches
tall, 24 inches tall, or 30 inches tall. In certain aspects, at
least about 50%, 60%, 70%, 80%, 90%, 95%, 98%, or 99% of the plants
in the population have at least 20 seeds, at least 30 seeds, at
least 40 seeds, at least 50 seeds, or at least 60 seeds. In certain
aspects, the plant is a cotton plant and at least about 50%, 60%,
70%, 80%, 90%, 95%, 98%, or 99% of the plants in the population
have reached a stage in their life cycle wherein pinhead squares
have formed.
[0097] In certain aspects, the population of plants is grown at an
average density of at least 10 plants per square meter. In certain
aspects, the population of plants is grown at an average density of
at least 30 plants per square meter. In certain aspects, the
population of plants is grown at an average density of at least
about 60 plants per square meter. In certain aspects, the
population of plants is grown at an average density of at least 67
plants per square meter. In certain aspects, the population of
plants is grown at an average density of at least 75 plants per
square meter. In certain aspects, the population of plants is grown
at an average density of at least 100 plants per square meter. In
certain aspects, the population of plants is grown at an average
density of at least 125 plants per square meter. In certain
aspects, the population of plants is grown at an average density of
at least 150 plants per square meter. In certain aspects, the
population of plants is grown at an average density of about 10,
30, 60, 75, 100, 125, or 150 plants per square meter or any range
in between.
[0098] In certain aspects, the population of plants comprises at
least about 50 cotton plants, at least about 100 cotton plants, at
least about 500 cotton plants, at least about 1,000 cotton plants,
at least about 5,000 cotton plants, at least about 10,000 cotton
plants, at least about 100,000 cotton plants, at least about
500,000 cotton plants, at least about 1,000,000 cotton plants.
Similarly, in certain aspects, the population of plants comprises
50 or more cotton plants, 100 or more cotton plants, 500 or more
cotton plants, 1,000 or more cotton plants, 5,000 or more cotton
plants, 10,000 or more cotton plants, 100,000 or more cotton
plants, 500,000 or more cotton plants, or 1,000,000 or more cotton
plants.
[0099] Certain aspects provide for a cotton plant grown under any
of the stressed conditions disclosed herein, and grown as a member
of a population of cotton plants, wherein the cotton plant is grown
in the population with an average density of at least 10, 30, 60,
67, 75, 100, 125, or 150 plants per square meter, for at for at
least 40 days, for at least 50 days, for at least 60 days, for at
least 70 days, or for at least 80 days during the time from when
the cotton seed germinates to when the cotton plant produces at
least one cotton boll that contains a seed, wherein the seed
comprises at least one embryo with a cotyledon in the primordia
stage.
Plant Breeding
[0100] In addition to growing a plant, such as to produce a plant
with an altered morphology and/or produce a seed, methods provided
herein also apply the methods of growing a plant for breeding
purposes. In certain aspects, at least one seed is collected from a
plant grown by at least one of the aforementioned methods and/or
having one of the aforementioned morphologies. In certain aspects,
the collected seed or plant grown from the seed can be tested (also
referred to as "screened") for traits. In certain aspects, the seed
is tested by genotyping and/or phenotyping. In certain aspects, the
information obtained by testing is used as the basis for growing
and/or crossing a plant or otherwise used in a plant breeding
program.
[0101] Commercial plants, such as cotton, are generally grown in
open fields because the space needed to grow large populations of
plants. One advantage of growing plants with an altered morphology,
in particular plants with reduced height compared to control
plants, is that shorter plants tend to also be more compact
overall, i.e., they take up less space. This attribute--as well as
the potential of using a reduced amount of soil volume per
plant--allows plants to be grown at higher densities than
recommended or considered viable to produce plants capable of seed
production. Under normal planting densities, a population of 1000
cotton plants requires about 40,000 square meters of space. Using
the methods described herein that reduce the size of the plants,
the same size population can be grown with only about 4,800 square
meters of space. This makes it much more feasible to grow large
populations of plants in controlled environments, such as to
exclude pollinating insect that may interfere with crosses made for
plant breeding. In certain aspects, a plant is grown as part of a
population of plants where the average density of plants is at
least 10 plants per square meter. In certain aspects, a plant is
grown as part of a population of plants where the average density
of plants is at least 30 plants per square meter. In certain
aspects, a plant is grown as part of a population of plants where
the average density of plants is at least 60 plants per square
meter. In certain aspects, a plant is grown as part of a population
of plants where the average density of plants is at least 67 plants
per square meter. In certain aspects, a plant is grown as part of a
population of plants where the average density of plants is at
least 75 plants per square meter. In certain aspects, a plant is
grown as part of a population of plants where the average density
of plants is at least 100 plants per square meter. In certain
aspects, a plant is grown as part of a population of plants where
the average density of plants is at least 125 plants per square
meter. In certain aspects, a plant is grown as part of a population
of plants where the average density of plants is at least 150
plants per square meter. In certain aspects, a plant is grown as
part of a population of plants where the average density is about
10, 30, 60, 75, 100, 125, or 150 plants per square meter or any
range in between. Certain aspects provide for such a population of
plants wherein the population comprises plants with an altered
morphology and/or grown according to the methods provided
herein.
[0102] A population of plants with an average density disclosed
anywhere herein may be relatively small to very large. In certain
aspects, the population of plants comprises at least about 50
cotton plants, at least about 100 cotton plants, at least about 500
cotton plants, at least about 1,000 cotton plants, at least about
5,000 cotton plants, at least about 10,000 cotton plants, at least
about 100,000 cotton plants, at least about 500,000 cotton plants,
at least about 1,000,000 cotton plants. Similarly, in certain
aspects, the population of plants comprises 50 or more cotton
plants, 100 or more cotton plants, 500 or more cotton plants, 1,000
or more cotton plants, 5,000 or more cotton plants, 10,000 or more
cotton plants, 100,000 or more cotton plants, 500,000 or more
cotton plants, or 1,000,000 or more cotton plants. The population
may be grown under controlled conditions. In certain aspects, at
least about 50%, 60%, 70%, 80%, 90%, 95%, 98%, or 99% of the plants
in the population are at their reproductive stage. In certain
aspects, at least about 50%, 60%, 70%, 80%, 90%, 95%, 98%, or 99%
of the plants in the population produce seed. In certain aspects,
the plant is a cotton plant and at least about 50%, 60%, 70%, 80%,
90%, 95%, 98%, or 99% of the cotton plants in the population have
reached a stage in their life cycle wherein pinhead squares have
formed.
[0103] In certain aspects, at least about 75%, 80%, 85%, 90%, 95%,
98%, or 99% of the plants in the population produce at least 20
seeds, at least 30 seeds, at least 40 seeds, at least 50 seeds, or
at least 60 seeds. In certain aspects, at least about 75%, 80%,
85%, 90%, 95%, 98%, or 99% of the plants in the population are less
than about 30 inches tall, less than about 24 inches tall, less
than about 18 inches tall, less than about 15 inches tall, or less
than about 12 inches tall. In certain aspects, the average height
of the population is less than about 30 inches tall, less than
about 24 inches tall, less than about 18 inches tall, less than
about 15 inches tall, or less than about 12 inches tall.
[0104] Under normal commercial planting conditions, a cotton plant
produces from about 18 to about 30 nodes, with the first fruiting
node between node 5 and 9. When plants are grown under the stressed
conditions disclosed herein, bolls typically set at nodes 5 or 6,
one boll per plant.
[0105] Types of Plants
[0106] Unless otherwise specified, this disclosure is not limited
to any particular type of plant. In certain aspects, the plant is a
crop plant. Representative examples of crop plants include: a corn
or maize plant, a soybean plant, a canola plant, a cotton plant, a
wheat plant, and a sugarcane plant. In certain aspects, the plant
is a cotton plant. In another aspect, a plant provided herein is
selected from the group consisting of Acacia plant, an alfalfa
plant, an aneth plant, an apple plant, an apricot plant, an
artichoke plant, an arugula plant, an asparagus plant, an avocado
plant, a banana plant, a barley plant, a bean plant, a beet plant,
a blackberry plant, a blueberry plant, a broccoli plant, a Brussels
sprout plant, a cabbage plant, a canola plant, a cantaloupe plant,
a carrot plant, a cassava plant, a cauliflower plant, a celery
plant, a Chinese cabbage plant, a cherry plant, a cilantro plant, a
citrus plant, a clementine plant, a coffee plant, a corn plant, a
cotton plant, a cucumber plant, a Douglas fir plant, an eggplant
plant, an endive plant, an escarole plant, an eucalyptus plant, a
fennel plant, a fig plant, a forest tree plant, a gourd plant, a
grape plant, a grapefruit plant, a honey dew plant, a jicama plant,
kiwifruit plant, a lettuce plant, a leek plant, a lemon plant, a
lime plant, a Loblolly pine plant, a mango plant, a maple tree
plant, a melon plant, a mushroom plant, a nectarine plant, a nut
plant, an oat plant, an okra plant, an onion plant, an orange
plant, an ornamental plant plant, a papaya plant, a parsley plant,
a pea plant, a peach plant, a peanut plant, a pear plant, a pepper
plant, a persimmon plant, a pine plant, a pineapple plant, a
plantain plant, a plum plant, a pomegranate plant, a poplar plant,
a potato plant, a pumpkin plant, a quince plant, a radiata pine
plant, a radicchio plant, a radish plant, a rapeseed plant, a
raspberry plant, a rice plant, a rye plant, a sorghum plant, a
Southern pine plant, a soybean plant, a spinach plant, a squash
plant, a strawberry plant, a sugar beet plant, a sugarcane plant, a
sunflower plant, a sweet corn plant, a sweet potato plant, a
sweetgum plant, a tangerine plant, a tea plant, a tobacco plant, a
tomato plant, a turf plant, a vine plant, watermelon plant, a wheat
plant, a yam plant, and a zucchini plant.
[0107] The plant may be any whole plant, or part of a plant, or
tissue culture derived from a plant, or plant seed. In certain
aspects, the plant is a cotton plant, a maize plant, or a soybean
plant. A cotton plant for use in methods described herein can be at
any of various developmental stages.
[0108] Table 1 describes different cotton developments stages.
TABLE-US-00001 TABLE 1 Accumulated DD60s Heat Units Previous
Developmental Stage Days Methods New Methods* Planting to Emergence
4 to 9 50 to 60 76-171 Emergence to First Square 27 to 38 425 to
475 513-722 Square to Flower 20 to 25 300 to 350 380-475 Planting
to First Flower 60 to 70 775 to 850 1140-1330 *based on a
hypothetical example with consistent daily high temperatures of
90.degree. F. (32.2.degree. C.) and consistent daily low
temperatures of 68.degree. F. (20.degree. C.).
[0109] DD60s are the accumulated heat units a plant receives each
day and are determined by averaging each day's maximum and minimum
temperatures and then subtracting 60, i.e. DD60 =((.degree.
Fmax+.degree. Fmin)/2) -60. The DD60s calculated for each day are
added to determine the total DD60s for a given number of growing
days.
Flower Timing
[0110] Within a population of plants, even for plants planted at
the same time, the time at which they mature and/or start to flower
and/or produce seeds is not necessarily simultaneous. For example,
FIGS. 5 and 6 show a distribution of when standard cotton plants in
a population start to flower, starting with just a small percentage
in the first few days, then increasing over several days, and then
the numbers tail off (FIG. 5) until 100% have flowered (cumulative
shown in FIG. 6). In current methods of growing cotton plants under
standard conditions, the time of flowering and seed maturation can
be spread across a number of days or even weeks. Thus, this may
require multiple rounds of gathering samples if it is desired to
gather the samples at the same point of maturation throughout the
population.
[0111] It has been discovered that for a population of plants grown
according to methods utilizing the stressed conditions disclosed
herein and/or having the resultant reduced statute morphology, the
window of flowering time of the plants in the population is more
synchronized (narrower) compared to control plants grown under
standard conditions. That is, the window of time from when the
first plants in the population begin to flower and/or produce seed
and when a significant percentage, substantially all, or all of the
plants in the population have flowered and/or produced seed is
shorter. For example, in certain aspects, cumulatively 50%, 60%,
70%, 75%, 80%, 90%, 95%, 98%, 99%, or 100% of plants in a
population of cotton plants disclosed herein have flowered and/or
produced seed within 1 day , 2 days, 3 days, 4 days, 5 days, 6
days, 7 days, 8 days, 9 days, 10 days, 11 days, 12 days, 13 days,
or 14 days from when the first plant in population flowers and/or
produces seed. For example, in certain aspects, cumulatively 50%,
60%, 70%, 75%, 80%, 90%, 95%, 98%, 99%, or 100% of plants in a
population of cotton plants disclosed herein have flowered and/or
produced seed within 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50,
51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67,
68, 69, 70, 71, 72, 73, 74, or 75 days after planting. In certain
aspects, the timespan between when the first plant in a population
of cotton plants begins to flower and/or produce seed and
cumulatively 50%, 60%, 70%, 75%, 80%, 90%, 95%, 98%, 99%, or 100%
of plants in a population have flowered and/or produced seed is 1%,
2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 12%, 15%, 20%, 25%, 30%, 33%,
35%, 40%, 50%, 60%, 70%, 75%, or 80% less time in comparison to a
control population of plants. As disclosed herein, the population
of plants comprises at least about 50 cotton plants, at least about
100 cotton plants, at least about 500 cotton plants, at least about
1,000 cotton plants, at least about 5,000 cotton plants, at least
about 10,000 cotton plants, at least about 100,000 cotton plants,
at least about 500,000 cotton plants, at least about 1,000,000
cotton plants. Similarly, in certain aspects, the population of
plants comprises 50 or more cotton plants, 100 or more cotton
plants, 500 or more cotton plants, 1,000 or more cotton plants,
5,000 or more cotton plants, 10,000 or more cotton plants, 100,000
or more cotton plants, 500,000 or more cotton plants, or 1,000,000
or more cotton plants.
[0112] It is contemplated that tighter synchronization of
maturation, flowering, and/or seed production timing will permit
breeders to more consistently predict when plants in a population
will flower and/or produce seeds. This reduced variability in
developmental timing will improve operations and timing in, for
example, industrial breeding programs, thereby reducing overall
cycle time and resource waste.
EXAMPLES
[0113] The following examples are included to demonstrate certain
aspects of the invention. It should be appreciated by those of
skill in the art that the techniques disclosed in the examples
which follow represent techniques discovered by the inventor to
function well in the practice of the invention. However, those of
skill in the art should, in light of the present disclosure,
appreciate that many changes can be made in the specific aspects
which are disclosed and still obtain a like or similar result
without departing from the spirit and scope of the invention.
Example 1
Cotton Plants Grown Under High Stress and High Density
[0114] Approximately 188,000 plant pots, each comprising dimensions
of approximately 7 cm wide.times.approximately 7 cm
long.times.approximately 8 cm deep (for a total interior volume of
slightly less than 400 mL) were assembled and prepared to receive
growth media and seeds. Into each pot, approximately 380 mL of wet
peat moss media was placed, along with Osmocote fertilizer
following the manufacturer's recommendations. Into each pot, 2-3 F2
seeds of a certain cotton hybrid variety were planted.
[0115] Pots containing soil and seeds were then arranged into
high-density growing blocs, each bloc comprising 324 pots in a 4.8
m.sup.2 area. 580 of these blocs were squeezed into a shade house,
such that a total of 187,920 pots comprised a total of 2,784
m.sup.2 controlled environment space. The pots were arranged into
this growing density immediately after seeds were planted and from
that point on, the plants were subjected to the following
temperature and irrigation stress conditions, in addition to the
reduced soil volume and/or population density.
[0116] High Temperature. Due to the prevailing climate of the
latitude and region where the greenhouse was located (Costa Rica),
the temperature variation in any 24-hour photocycle remained
predictable throughout the growing period. During each 24-hour day,
the temperatures would rise from nighttime lows of 18-22.degree.
C., rapidly reaching 30.degree. C. in the morning when the
greenhouse was in direct sun, and continuing to increase to an
afternoon maximum of 35-45.degree. C., which was maintained for at
least 2-12 hours, each day. Temperatures dropped in the evenings,
especially after the sunset, to eventually return to a nighttime
low, which typically occurred between 1 a.m. and 4 a.m.
[0117] Reduced Irrigation. Plants were irrigated via drip lines so
that the volume of water accessible to the plant over any period of
time could be carefully metered and controlled. Irrigation was
provided through overhead sprinklers. To determine and control the
amount of irrigation each plant received, several samples of plants
were weighed before and after each irrigation. The weight gained
was converted to volume of water and then divided by the total
number of plants in the sample to determine the average amount of
water each plant had received. Through careful weighing and
sampling, this system was calibrated so that an average volume of
water could be reliably, and verifiably, delivered to each plant in
the covered environment. Through extensive testing across many
growing cycles, it was discovered that approximately 100 mL of
water per plant per 24-hour period was sufficient to keep the plant
alive and induce the desired miniaturized morphology.
[0118] After approximately 3 days after planting (DAP), seedlings
began to emerge from the pots. As emergence and growth proceeded,
some pots produced more than one seedling (2-3 seeds were
planted/pot to ensure at least one seedling/pot would be
recovered), so additional seedlings were removed from those pots so
that all pots produced only one seedling per pot ("doubles" and
"triples" were culled down to singles). Thus, a total of 187,920
plants were now growing within a total of 2,784 m.sup.2 within the
controlled environment. During the next few days, plants were
allowed to self-pollinate.
[0119] At 20 DAP, a plant treatment agent comprising mepiquat was
applied. Approximately 0.5 L of PIX.RTM. per hectare was applied to
the plants. Application comprised homogenizing 139 mL of PIX.RTM.
in 20 L of water and loading the mixture into a backpack sprayer
and then using the sprayer to apply the diluted PGR to the
approximately 188,000 plants growing in the controlled environment.
This same treatment was reapplied to the plants three more times in
the following weeks, up until 60 DAP.
[0120] It was noted that the total volume of liquid added to the
plants in any one day that the PGR was applied amounted to
approximately 0.5 mL per plant, and so was considered a negligible
amount of additional irrigation beyond the 100 mL that was meted
out to each plant each day.
[0121] At approximately 25 DAP, at least one pinhead square
appeared on all of the plants, typically at the 5.sup.th node. By
46-50 DAP, most plants had developed fully-formed flowers and by 60
DAP, all plants had flowers. Between 86-100 DAP, fully-mature bolls
were harvested from the plants and the seeds within recovered. Seed
yield was typically 20-30 seeds per boll.
[0122] In this example, at least 20 seeds were recovered from each
of the 187,920 plants, all of which were cultivated within a 2,784
m.sup.2 area of controlled environment. Producing seeds from this
same number of crosses using current research methods, wherein
cotton plants are typically planted at approximately 10
plant/m.sup.2 in the field, would require approximately 18,800
m.sup.2, or 1.8 hectares. Thus, the methods described herein allow
one to produce seeds from the same number of crosses using only
10.5% of the growing area of current protocols.
[0123] Table 3a-g below shows data comparing field grown plants not
subjected to stressed conditions in comparison to mini-cotton
plants grown according to stressed conditions disclosed herein. At
both early and late times, plants grown under the stressed
conditions were significantly smaller in all aspects measured than
field grown plants.
TABLE-US-00002 TABLE 3a Days After Average of Height Planting
Number from Cotyledon to Row Labels (DAP) of Plants Last open leaf
(cm) Early Field plant-PIX application 34 10 Field plant-PIX
application 21.95 Mini plants-PIX application 17 5 Mini plants-PIX
application 9.8 Late Field Plant-Near Cut off 86 5 Field Plant-Near
Cut off 162.4 Mini Plant Harvest 119 5 Mini Plant Harvest 29.3
TABLE-US-00003 TABLE 3b Average of # Average of # Nodes Bolls Early
Field plant-PIX application 8.7 Field plant-PIX application n/a
Mini plants-PIX application 3 Mini plants-PIX application n/a Late
Field Plant-Near Cut off 26.8 Field Plant-Near Cut off 21.2 Mini
Plant Harvest 8.6 Mini Plant Harvest 1.2
TABLE-US-00004 TABLE 3c Average of 1st Average of Weight Node with
boll from N0 and up (grams) Early Field plant-PIX application 5.4
Field plant-PIX application 25.67 Mini plants-PIX application 0
Mini plants-PIX application 6.2 Late Field Plant-Near Cut off 5.6
Field Plant-Near Cut off 1028 Mini Plant Harvest 5.6 Mini Plant
Harvest 18.1
TABLE-US-00005 TABLE 3d Average of Flowers/ Average of Flowers/
Fruits-Fresh Weight Fruits-Dry Weight at site (grams) at lab
(grams) Early Field plant-PIX application 0.21 Field plant-PIX
application 0.045 Mini plants-PIX application 0 Mini plants-PIX
application 0 Late Field Plant-Near Cut off 307.44 Field Plant-Near
Cut off 46.6 Mini Plant Harvest 6.58 Mini Plant Harvest 5.55
TABLE-US-00006 TABLE 3e Average of Leaves- Average of Leaves- Fresh
Weight at site Dry Weight at lab (grams) (grams) Early Field
plant-PIX application 18.72 Field plant-PIX application 2.679 Mini
plants-PIX application 3.68 Mini plants-PIX application 0.14 Late
Field Plant-Near Cut off 281.84 Field Plant-Near Cut off 65.9 Mini
Plant Harvest 5.92 Mini Plant Harvest 1.296
TABLE-US-00007 TABLE 3f Average of Stem-Fresh Average of Stem-Dry
Weight at site (grams) Weight at lab (grams) Early Field plant-PIX
application 4.91 Field plant-PIX application 0.363 Mini plants-PIX
application 0.74 Mini plants-PIX application 0.062 Late Field
Plant-Near Cut off 342.16 Field Plant-Near Cut off 90.66 Mini Plant
Harvest 5.16 Mini Plant Harvest 1.704
TABLE-US-00008 TABLE 3g Ave. dry weight total (grams) (sum of above
dry weights) Early Field plant-PIX application 3.087 Mini
plants-PIX application 0.202 Late Field Plant-Near Cut off 203.16
Mini Plant Harvest 8.55
* * * * *