U.S. patent application number 11/116736 was filed with the patent office on 2005-08-25 for brassica napus with early maturity (early napus) and resistance to an ahas-inhibitor herbicide.
This patent application is currently assigned to Pioneer Hi-Bred International, Inc.. Invention is credited to Charne, David G., Grombacher, Alan W., Patel, Jayantilal D..
Application Number | 20050188437 11/116736 |
Document ID | / |
Family ID | 4167702 |
Filed Date | 2005-08-25 |
United States Patent
Application |
20050188437 |
Kind Code |
A1 |
Charne, David G. ; et
al. |
August 25, 2005 |
Brassica napus with early maturity (Early Napus) and resistance to
an AHAS-inhibitor herbicide
Abstract
Improved varieties of Brassica napus having early maturity
("Early Napus") and resistance to an AHAS-inhibitor herbicide, such
as an imidazolinone, are provided. These varieties may be used to
produce inbreds or hybrids or to produce vegetable oil and meal.
Parts of these plants, including plant cells, are also
provided.
Inventors: |
Charne, David G.; (Guelph,
CA) ; Patel, Jayantilal D.; (Thornhill, CA) ;
Grombacher, Alan W.; (Beaumont, CA) |
Correspondence
Address: |
PIONEER HI-BRED INTERNATIONAL INC.
7100 N.W. 62ND AVENUE
P.O. BOX 1000
JOHNSTON
IA
50131
US
|
Assignee: |
Pioneer Hi-Bred International,
Inc.
|
Family ID: |
4167702 |
Appl. No.: |
11/116736 |
Filed: |
April 28, 2005 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
11116736 |
Apr 28, 2005 |
|
|
|
09994092 |
Nov 16, 2001 |
|
|
|
6914171 |
|
|
|
|
Current U.S.
Class: |
800/278 ;
800/281; 800/306 |
Current CPC
Class: |
A01H 5/10 20130101 |
Class at
Publication: |
800/278 ;
800/281; 800/306 |
International
Class: |
A01H 001/00; C12N
015/82; A01H 005/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 17, 2000 |
CA |
2,326,283 |
Claims
What is claimed is:
1. A Brassica napus progeny plant or plant part of variety NS3801,
wherein the variety contains alleles fixed for Early Napus and
resistance to at least one AHAS-inhibitor herbicide and wherein the
progeny plant or plant part also contains the fixed alleles and is
Early Napus and resistant to at least one AHAS-inhibitor herbicide,
representative seed of variety NS3801 having been deposited under
ATCC Accession No. PTA-2470.
2. A Brassica napus progeny plant seed of variety NS3801, wherein
the variety contains alleles fixed for Early Napus and resistance
to at least one AHAS-inhibitor herbicide and wherein the progeny
plant seed also contains the fixed alleles and is Early Napus and
resistant to at least one AHAS-inhibitor herbicide, representative
seed of variety NS3801 having been deposited under ATCC Accession
No. PTA-2470.
3. A Brassica napus progeny plant cell of variety NS3801, wherein
the variety contains alleles fixed for Early Napus and resistance
to at least one AHAS-inhibitor herbicide and wherein the progeny
plant cell also contains the fixed alleles and is Early Napus and
resistant to at least one AHAS-inhibitor herbicide, representative
seed of variety NS3801 having been deposited under ATCC Accession
No. PTA-2470.
4. A method for preparing oil and/or meal from a seed of Brassica
napus variety NS3801, the method comprising crushing the seed and
separating the oil and/or seed, representative seed of variety
NS3801 having been deposited under ATCC Accession No. PTA-2470.
5. The method according to claim 4, wherein the oil has less than
2% erucic acid.
6. The method of claim 4, wherein the meal has a glucosinolate
content of less than 30 .mu.mol per gram of defatted meal.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. Ser. No.
09/994,092 which claims priority under 35 USC 119(a) to Canadian
Application No. 2,326,283 filed Nov. 17, 2000.
FIELD OF THE INVENTION
[0002] This invention is in the field of canola breeding. In
particular, it relates to improved varieties of canola (Brassica
napus) having early maturity ("Early Napus"), in combination with
resistance to at least one AHAS-inhibitor herbicide.
BACKGROUND OF THE INVENTION
[0003] Canola is an important agricultural crop in Canada, the
United States, Europe and Australia. Weed competition and earliness
of maturity are significant limiting factors in canola crop
production and quality. The challenge for plant scientists has been
to develop canola varieties having superior performance with
respect to these limiting factors, while at the same time having
satisfactory agronomic characteristics, including yield potential,
lodging resistance, oil and protein content, and glucosinolate
levels that are sufficiently low for registration.
[0004] Resistance to AHAS-Inhibitor Herbicides
[0005] Herbicide resistant plants are plants that are able to
survive and reproduce following exposure to herbicides at rates of
application that would prevent non-herbicide resistant varieties of
the same species from surviving and reproducing. Herbicide
resistance is particularly important for Brassica, since many
weeds, such as stinkweed, shepherd's purse, flixweed, ball mustard,
wormseed mustard, hare's ear mustard and common peppergrass have a
close genetic relationship with Brassica. Therefore, it is
advantageous for a cultivar to have herbicide resistance not
possessed by related weeds.
[0006] Some herbicides function by disrupting amino acid
biosynthesis in affected species. For example, AHAS-inhibitor
herbicides (also known as ALS-inhibitor herbicides) function by
inhibiting the enzyme acetohydroxy acid synthase (AHAS), the first
enzyme in the biosynthesis of the amino acids, isoleucine, leucine
and valine. In plants with resistance to an AHAS-inhibitor
herbicide, inhibition of the AHAS enzyme is prevented, thus
allowing the plant to continue with normal amino acid biosynthesis.
Most forms of Brassica are highly susceptible to AHAS-inhibitor
herbicides, such as imidazolinones and sulfonylureas.
[0007] The development of canola with resistance to imidazolinones,
such as PURSUIT.TM. and ODYSSEY.TM., was a major breakthrough in
weed management technology. The imidazolinones are a family of
broad spectrum herbicides which may be applied for in-crop weed
control. They control a larger number of problem species than
herbicides used in non-herbicide resistant varieties, and offer
greater management flexibility, including timing of application and
tank mixing. An advantage of imidazolinone ("IMI") resistant
varieties over many other herbicide resistant varieties, such as
ROUNDUP READY.TM. (glyphosate) or LIBERTY LINK.TM. (glufosinate)
resistant varieties, is that some imidazolinone herbicides have a
soil residual which controls successive weed flushes. This provides
a significant advantage to farmers, because it enables them to
achieve longer term weed control without a second application of
herbicide. Effective weed control increases yield by reducing
competition from weed species. It also improves grain quality
through the elimination of cruciferous weed seeds. It may also
improve weed management in other crops in the rotation, due to
reduced weed pressure.
[0008] However, a drawback of currently available IMI resistant
varieties is that they lack many of the desirable traits found in
elite varieties of non-herbicide resistant canola. In particular,
none of the currently available canola varieties have the desirable
combination of IMI resistance and early maturity (Early Napus). It
is particularly difficult to develop varieties having IMI
resistance, in combination with other desirable traits, because the
inheritance of the IMI resistance trait is relatively complex.
Unlike the ROUNDUP READY.TM. trait or LIBERTY LINK.TM. trait, which
are controlled by single transgenes that exhibit complete
dominance, the IMI resistance trait is controlled by two unlinked
gene pairs having partial dominance. Swanson et al., Plant Cell
Reports 7:83-87 (1989) reported the development of imidazolinone
herbicide tolerant Brassica napus mutants using microspore
mutagenesis. During the process, five fertile double-haploid
Brassica napus mutant plants were developed. One of the mutants was
tolerant to between 5 and 10 times the recommended field traits of
an imidazolinone herbicide. An inheritance study indicated that two
semi-dominant unlinked genes combined to produce an F1 with greater
tolerance than either of the parents.
[0009] Rutledge et al., Mol. Gen. Genet. 229:31-40 (1991) proposed
a model for the inheritance of the five AHAS genes in Brassica
napus. AHAS2, AHAS3 and AHAS4 appear to be associated with the `A`
(rapa) genome and AHAS1 and AHAS5 are likely associated with the
`C` (oleracea) genome. AHAS1 and AHAS3 are expressed at all growth
stages (Ouellet et al., Plant J. 2:321-330 1992) and mutant forms
of AHAS1 and AHAS3 appear to be the most effective tolerance genes.
AHAS2 was found to be active only in ovules and seeds. AHAS4 was
found to be defective due to interrupted sequences in the middle of
the coding region (Rutledge et al., Mol. Gen Genet. 229:3140 1991)
and was not expressed in tissues examined by Ouellet et al., Plant
J. 2:321-330 (1992). The last gene AHAS5, may also be defective
(Rutledge et al. Mol. Gen Genet. 229:3140,1991). Hattori et al. Can
J. Bot: 70:1957-1963, (1992) determined that the DNA sequence of
the coding regions for AHAS1 and AHAS3 were 98% identical. DNA
sequences of the 5' and the 3' ends were also closely related. Few
similarities were observed between the sequence of the AHAS2
compared to the AHAS1 or AHAS3 genes.
[0010] There are two effective mutations for IMI resistance in
commercial use--an AHAS1 mutant (believed to be located on the C
genome) and an AHAS3 mutant (believed to be located on the A
genome). The AHAS3 mutant also provides resistance to other
AHAS-inhibitor herbicides, such as sulfonylureas. The complexity of
the inheritance of the IMI resistance trait results in multiple
phenotypes during segregating generations, which presents a
significant hurdle to plant breeders. Accordingly, there is a need
to develop an AHAS-inhibitor herbicide resistant canola variety
with improved performance characteristics.
[0011] Early Napus
[0012] Early maturity is an important trait in Brassica napus
varieties, especially in market areas with a limited frost-free
period. Late summer frosts can damage the crop before it is fully
mature, resulting in elevated green seed content of the grain (a
grading criterion) and increased chlorophyll in the oil (a quality
problem). High green seed results in losses to the producer, while
elevated chlorophyll in the oil increases processing costs, and
results in a loss of value for food end users. Early Napus is also
important where early maturity reduces exposure to extreme heat and
drought conditions during flowering and seed-filling.
[0013] To be classified as "Early Napus", a variety must have an
average maturity which is at least four days earlier than the
average maturity of the current WCC/RRC (Western Canadian
Canola/Rapeseed Recommending Committee) check varieties
(DEFENDER.TM., EXCEL.TM., and LEGACY.TM.) over two years at 11
locations in the Short Season Zone of Western Canada. No known
varieties of Brassica napus have the desirable combination of Early
Napus and resistance to an AHAS-inhibitor herbicide, such as an
imidazolinone. Therefore, there is a need for a Brassica napus
variety which combines the advantageous traits of early maturity
(Early Napus) and resistance to AHAS-inhibitor herbicides.
[0014] Accordingly, it is an object of the present invention to
provide an improved variety of Brassica napus having early maturity
(Early Napus) and resistance to at least one AHAS-inhibitor
herbicide, such as an imidazolinone. These and other objects of the
invention will be apparent to those skilled in the art from the
following description and claims.
SUMMARY OF THE INVENTION
[0015] This invention provides a Brassica napus plant which is
Early Napus and resistant to at least one AHAS-inhibitor herbicide,
such as an imidazolinone (e.g. imazethapyr or imazamox) or a
sulfonylurea [e.g. thifensulfuron methyl (REFINE.TM.)]. In one
embodiment, it relates to canola variety NS3801.
[0016] This invention also relates to tissue cultures of
regenerable cells from the plants described above, as well as to
the use of the tissue cultures for regenerating canola plants that
are Early Napus and resistant to at least one AHAS-inhibitor
herbicide, such as an imidazolinone or a sulfonylurea. It also
relates to the plants produced therefrom.
[0017] This invention further relates to the parts of the Brassica
napus plants described above, including their cells, pollen,
ovules, roots, leaves, seeds, microspores and vegetative parts,
whether mature or embryonic. It also relates to the use of these
plant parts for regenerating a canola plant that is Early Napus and
resistant to at least one AHAS-inhibitor herbicide, such as an
imidazolinone or a sulfonylurea, and to the plants regenerated
therefrom.
[0018] This invention further relates to the use of the plants
described above for breeding a Brassica line, through pedigree
breeding, crossing, self-pollination, haploidy, single seed
descent, modified single seed descent, and backcrossing, or other
suitable breeding methods, and to the plants produced therefrom.
This invention also relates to a method for producing a first
generation (F1) hybrid canola seed by crossing one of the plants
described above with an inbred canola plant of a different variety
or species, and harvesting the resultant first generation (F1)
hybrid canola seed. It further relates to the plants produced from
the F1 hybrid seed.
[0019] This invention also relates to the use of the Brassica napus
plants described above for producing oil and/or meal, and to the
vegetable oil and meal produced therefrom. Preferably, the plant is
capable of producing oil with less than 2% erucic acid and meal
with less than 30 .mu.mol of glucosinolates per gram of defatted
meal.
[0020] This invention provides substantial value to both producers
and users of canola by providing hitherto unavailable combinations
of early maturity (Early Napus) and resistance to at least one
AHAS-inhibitor herbicide. This trait combination improves weed
control, while improving or stabilizing grain quality by reducing
green seed count.
DETAILED DESCRIPTION OF THE INVENTION
[0021] In accordance with this invention, improved varieties of
Brassica napus having early maturity (Early Napus) and resistance
to at least one AHAS-inhibitor herbicide are developed by crossing
a parent with resistance to an AHAS-inhibitor herbicide with one or
more parents having early maturity (Early Napus), wherein the
herbicide resistant parent and the Early Napus parent(s) together
have the genetic basis for the complement of characteristics
desired in the progeny. Self-pollination or sib-mating following
crossing leads to a segregation of traits among the progeny.
Progeny having the desired combination of traits are selected after
exposure to one or more appropriate AHAS-inhibitor herbicides and
evaluation for desirable traits over successive generations.
[0022] Various breeding methods may be used, including haploidy,
pedigree breeding, single-seed descent, modified single seed
descent, recurrent selection, and backcrossing. Because of the
complex inheritance of the AHAS-inhibitor herbicide resistant
trait, we have found that haploidy is the most effective breeding
method. Parents having the desired complement of characteristics
are crossed in a simple or complex cross. Crossing (or
cross-pollination) refers to the transfer of pollen from one plant
to a different plant. Progeny of the cross are grown and
microspores (immature pollen grains) are separated and filtered,
using techniques known to those skilled in the art [(e.g. Swanson,
E. B. et al., Plant Cell Reports, "Efficient isolation of
microspores and the production of microspore-derived embryos in
Brassica napus", 6:94-97 (1987); and Swanson, E. B., Microspore
Culture in Brassica, pp. 159-169 in: Methods in Molecular Biology,
Vol. 6, Plant Cell and Tissue Culture, Humana Press (1990)]. These
microspores exhibit segregation of genes. The microspores are
cultured in the presence of an appropriate AHAS-inhibitor
herbicide, such as imazethapyr (e.g. PURSUIT.TM.) or imazamox (e.g.
RAPTOR.TM.) or a 50/50 mix of imazethapyr and imazamox (e.g.
ODYSSEY.TM.), which kills microspores lacking the mutations
responsible for resistance to the herbicide. Microspores carrying
the mutant genes responsible for resistance to the herbicide
survive and produce embryos, which form haploid plants. Their
chromosomes are then doubled to produce doubled haploids.
[0023] The doubled haploids are evaluated in subsequent generations
for herbicide resistance, early maturity, and other desirable
traits. AHAS-inhibitor herbicide resistance may be evaluated by
exposing plants to one or more appropriate AHAS-inhibitor
herbicides and evaluating herbicide injury. Earliness of maturity
can be evaluated through visual inspection of seeds within pods
(siliques) on the plants. Some other traits, such as lodging
resistance and plant height may also be evaluated through visual
inspection of the plants. Blackleg resistance may be evaluated by
inoculating plants with blackleg spores to induce the disease, and
observing resistance to infection. Other traits, such as oil
percentage, protein percentage, and total glucosinolates of the
seeds may be evaluated using techniques such as Near Infrared
Spectroscopy.
[0024] It is also possible to analyze the genotype of the plants,
using techniques such as Isozyme Electrophoresis, Restriction
Fragment Length Polymorphisms (RFLPs), Randomly Amplified
Polymorphic DNAs (RAPDs), Arbitrarily Primed Polymerase Chain
Reaction (AP-PCR), DNA Amplification Fingerprinting (DAF), Sequence
Characterized Amplified Regions (SCARs), Amplified Fragment Length
Polymorphisms (AFLPs), and Simple Sequence Repeats (SSRs) which are
also referred to as "Microsatellites".
[0025] Evaluation and manipulation (through exposure to one or more
appropriate AHAS-inhibitor herbicides, and blackleg infection)
typically occurs over several generations. The performance of the
new lines is evaluated using objective criteria in comparison to
check varieties. Lines showing the desired combination of traits
are self-pollinated to produce seed. Self-pollination refers to the
transfer of pollen from one flower to the same flower or another
flower of the same plant. Plants that have been self-pollinated and
selected for type for many generations become homozygous at almost
all gene loci and produce a uniform population of true breeding
progeny.
[0026] Other breeding methods may also be used. For example,
pedigree breeding is commonly used for the improvement of largely
self-pollinating crops such as canola. Pedigree breeding starts
with the crossing of two genotypes, each of which may have one or
more desirable characteristics that is lacking in the other or
which complements the other. If the two original parents do not
provide all of the desired characteristics, additional parents can
be included in the crossing scheme.
[0027] These parents are crossed in a simple or complex manner to
produce an F.sub.1. An F.sub.2 population is produced by selfing
one or several F.sub.1's or by intercrossing two F.sub.1's (i.e.,
sib mating). Selection of the best individuals may begin in the
F.sub.2 population, and beginning in the F.sub.3 the best families,
and the best individuals within the best families are selected.
Replicated testing of families (lines) can begin in the F.sub.4
generation to improve the effectiveness of selection for traits
with low heritability. At an advanced stage of inbreeding (i.e.,
F.sub.6 and F.sub.7), the best lines or mixtures of phenotypically
similar lines commonly are tested for potential release as new
cultivars.
[0028] The single seed descent (SSD) procedure may also be used to
breed improved varieties. The SSD procedure in the strict sense
refers to planting a segregating population, harvesting a sample of
one seed per plant, and using the population of single seeds to
plant the next generation. When the population has been advanced
from the F.sub.2 to the desired level of inbreeding, the plants
from which lines are derived will each trace to different F.sub.2
individuals. The number of plants in a population declines each
generation due to failure of some seeds to germinate or some plants
to produce at least one seed. As a result, not all of the plants
originally sampled in the F.sub.2 population will be represented by
a progeny when generation advance is completed.
[0029] In a multiple-seed procedure, canola breeders commonly
harvest one or more pods from each plant in a population and thresh
them together to form a bulk. Part of the bulk is used to plant the
next generation and part is put in reserve. The procedure has been
referred to as modified single-seed descent or the pod-bulk
technique. The multiple-seed procedure has been used to save labor
at harvest. It is considerably faster to thresh pods with a machine
than to remove one seed from each by hand for the single-seed
procedure. The multiple-seed procedure also makes it possible to
plant the same number of seeds of a population each generation of
inbreeding. Enough seeds are harvested to make up for those plants
that did not germinate or produce seed.
[0030] Backcross breeding can be used to transfer a gene or genes
for a simply inherited, highly heritable trait from one line or
cultivar (the donor parent) into another desirable cultivar or
inbred line (the recurrent parent). After the initial cross,
individuals possessing the phenotype of the donor parent are
selected and are repeatedly crossed (backcrossed) to the recurrent
parent. When backcrossing is complete, the resulting plant is
expected to have the attributes of the recurrent parent and the
desirable trait transferred from the donor parent.
[0031] Improved varieties may also be developed through recurrent
selection. A genetically variable population of heterozygous
individuals is either identified or created by intercrossing
several different parents. The best plants are selected based on
individual superiority, outstanding progeny, or excellent combining
ability. The selected plants are intercrossed to produce a new
population in which further cycles of selection are continued.
[0032] Regeneration of Plants
[0033] This invention also relates to the parts of the plants
disclosed herein, including plant cells, tissue, pollen, ovules,
roots, leaves, seeds, and microspores, whether mature or
embryonic.
[0034] The plants produced in accordance with the present invention
may be regenerated from plant parts using known techniques. For
instance, seeds from the plants of the present invention may be
planted in accordance with conventional Brassica growing
procedures. These plants will generate further seeds following
self-pollination. Alternatively, doubled haploid plantlets may be
extracted to immediately form homozygous plants, using known
procedures.
[0035] Brassica plants may also be regenerated using tissue culture
and regeneration. Tissue culture of various tissues of canola and
regeneration of plants therefrom is known to those skilled in the
art. For example, the propagation of a canola cultivar by tissue
culture is described in the following references: Chuong et al., "A
Simple Culture Method for Brassica Hypocotyl Protoplasts", Plant
Cell Reports 4:4-6 (1985); Barsby, T. L. et al. "A Rapid and
Efficient Alternative Procedure for the Regeneration of Plants from
Hypocotyls Protoplasts of Brassica napus", Plant Cell Reports,
(Spring 1996); Kartha, K. et al. "In vitro Plant Formation from
Stem Explants of Rape" Physiol. Plant, 31:217-220 (1974);
Narashimhulu, S. et al., "Species Specific Shoot Regeneration
Response of Cotyledenary Explants of Brassicas", Plant Cell
Reports, (Spring 1988); Swanson, E., "Microspore Culture in
Brassica", Methods of Molecular Biology, Vol. 6, Chapter 17, p. 159
(1990).
[0036] Use of Brassica as a Breeding Line
[0037] The Brassica napus plants of this invention may be used to
breed a novel Brassica line. The combination of desired traits
described herein, once established, can be transferred into other
Brassica napus plants by known plant breeding techniques including
self-pollination, crossing, recurrent selection, backcross
breeding, pedigree breeding, single seed descent, modified single
seed descent, haploidy, and other suitable breeding methods.
[0038] The desired traits can also be transferred between Brassica
species, such as B. napus, B. rapa (formerly known as B.
campestris), and B. juncea, using the same known plant breeding
techniques involving pollen transfer and selection. The transfer of
traits between Brassica species, such as napus and rapa by known
plant breeding techniques is well documented in the technical
literature (see for instance, Tsunada et al., 1980, Brassica Crops
and Wild Alleles Biology and Breeding", Japan Scientific Press,
Tokyo).
[0039] As an example of the transfer of the desired traits
described herein from napus to rapa, one selects a commercially
available rapa variety such as REWARD.TM., GOLDRUSH.TM., and
KLONDIKE.TM., and carries out an interspecific cross with one of
the plants from the present invention. After the interspecific
cross, members of the F1 generation are self-pollinated to produce
F.sub.2 oilseed. Selection for the desired traits is then conducted
on single F.sub.2 plants which are then backcrossed with the rapa
parent through the number of generations required to obtain a
euploid (n=10) rapa line exhibiting the desired combination of
traits.
[0040] In order to avoid inbreeding depression (e.g. loss of vigour
and fertility) that may accompany the inbreeding of Brassica rapa,
selected, i.e. BC.sub.1 plants that exhibit similar desired traits
while under genetic control advantageously can be sib-mated. The
resulting oilseed from these crosses can be designated
BC.sub.1SIB.sub.1 oilseed. Accordingly, the fixation of the desired
alleles can be achieved in a manner analogous to self-pollination
while simultaneously minimizing the fixation of other alleles that
potentially exhibit a negative influence on vigor and
fertility.
[0041] This invention is also directed to methods for producing an
F1 hybrid seed by crossing a first parent Brassica napus plant with
a second parent Brassica plant, wherein the first parent plant is
an inbred Brassica napus plant, such as canola variety NS3801,
which is Early Napus and resistant to at least one AHAS-inhibitor
herbicide. This invention is also related to the plants produced
from the F1 hybrid seed and the cells and other parts of those
plants.
[0042] Alternatively, both first and second parent Brassica plants
can come from the same varieties. Advantageously, one of the
Brassica varieties of the present invention is used in crosses with
a different Brassica inbred to produce first generation (F.sub.1)
canola hybrid seeds and plants with superior characteristics and
increased vigour.
[0043] Preferably when generating hybrid plants, the parent should
have glucosinolate levels that are sufficiently low to ensure that
the seed of the F.sub.1 hybrid has glucosinolate levels within
regulatory levels. The glucosinolate level of the seed harvested
from the F.sub.1 hybrid is roughly the average of the glucosinolate
levels of the male and female parents. For example, if the
objective is to obtain hybrid grain (F.sub.2) having a
glucosinolate level of less than 20 .mu.mol/g, and one parent has a
glucosinolate level of 15 .mu.mol/g, the other parent must have a
glucosinolate level of 25 .mu.mol/g or less.
[0044] Vegetable Oil and Meal
[0045] The seed of the plants of this invention may be used for
producing vegetable oil and meal. The seed of these varieties, the
plant produced from such seed, the hybrid canola plant produced
from the crossing of these varieties with other inbred varieties,
the resulting hybrid seed, and various parts of the hybrid canola
plant can be utilized in the production of an edible vegetable oil
or other food products in accordance with known techniques. The
remaining solid meal component derived from seeds can be used as a
nutritious livestock feed. Canola variety NS3801 can be used to
produce oil of improved quality, due to lower chlorophyll levels in
the oil. Preferably, the oil has less than 2% erucic acid and the
meal has less than 30 .mu.mol of glucosinolates per gram of
defatted meal.
[0046] A preferred embodiment of this invention is set forth below.
It should be understood, however, that the invention is not limited
to the specific details set forth in this example.
[0047] Development of the Improved IMI Resistant Brassica Napus
Line, NS3801.
[0048] Generation: Parent to F1
[0049] Seed Planted: BULLET.TM. and DEFENDER.TM., two spring canola
varieties developed by Svalof-Weibulls, and marketed commercially
by Proven Seed
[0050] Seed Harvested: 94SN-9514=(BULLET.TM./DEFENDER.TM.)
[0051] Method: Parents were grown and crossing was carried out in a
controlled environment in the greenhouse.
[0052] Generation: Single cross F1 to three-way cross F1
[0053] Seed Planted: 94SN-9514=(BULLET.TM..times.DEFENDER.TM.) and
45A71 (Breeder code NS1471, registered imidazolinone resistant
spring canola variety from Pioneer Hi-Bred, commercially available
from Proven Seed)
[0054] Seed Harvested:
96SN-0564=(45A71.times.(BULLET.TM..times.DEFENDER.T- M.)
[0055] Method: Parents were grown and crossing was carried out in a
controlled environment in the greenhouse. 45A71 was used as the
female parent. Approximately six female plants and more than 10
male plants were sampled in making the three-way cross. IMI
resistance was contributed by 45A71, which is homozygous for the
imidazolinone resistant genes.
[0056] Generation: Three way Cross F1 to doubled haploid
(F-infinity)
[0057] Seed Planted:
96SN-0564=(45A71.times.(BULLET.TM..times.DEFENDER.TM.- ))
[0058] Seed Harvested: 97DHS-6259
[0059] Method: Twelve plants of 96SN-0564 were planted in the
growth room under controlled environment as donor plants. These
plants were sprayed with the herbicide, PURSUIT.TM. (imazethapyr),
at 1.times.level. Immature buds were harvested from each donor
plant and were crushed in a blender to produce a slurry [as
described in Swanson, E. B. et al., "Efficient isolation of
microspores and the production of microspore-derived embryos in
Brassica napus" L. Plant Cell Reports 6: 94-97 (1987); and Swanson,
E. B. Microspore culture in Brassica, pgs. 159-169 in: Methods in
Molecular Biology vol. 6, Plant Cell and Tissue Culture, Humana
Press (1990)]. The slurry was then filtered through two layers of
Nitex filters (48 .mu.m pores) and collected in centrifuge tubes.
The suspensions were centrifuged, decanted and washed three times
for a total of 4 spins. Microspores were counted using a
haemocytometer and plated in NLN medium [Lichter, R., "Induction of
haploid plants from isolated pollen of Brassica napus, Z.
Pflanzenphysiol. Bd. 105: 427-434, (1982)], containing 40 .mu.g/l
PURSUIT.TM., at a density of 60,000 microspores per ml. Ten ml of
this suspension were poured into 100.times.25 mm petri plates
wrapped with parafilm, and placed in a Percival incubation chamber
at 32.5.degree. C. in darkness for 15 days. During this period the
microspores carrying imidazolinone-resistant genes were expected to
survive and produce embryos. After 15 days, petri plates with
cotyledonary embryos were put in a rotary shaker for 6 to 13 days
before being transferred to a solid 0.8% agar medium with 0.1%
Gibberillic acid (GA) in petri plates. Transferred embryos were
incubated in the dark at 4-8.degree. C. for 7-10 days and removed
to a Percival incubation chamber in light at 20 to 25.degree. C.
for 3 to 5 weeks. Selected embryos that regenerated were placed in
soil in 72 cell flats or put back onto 0.8% agar with 0.1% GA for a
further 3 to 5 weeks before they were transplanted into the soil.
Before flowering, plants were treated with 0.33% colchicine for 1.5
to 2.5 hours. Plant roots were washed free of soil prior to
incubation in the colchicine solution. After treatment they were
planted in 10 cm plastic pots. Upon flowering, plants with fertile
(diploid) racemes were covered with perforated, clear plastic bags
to produce selfed seeds. After flowering, bags were removed and
plants were dried down, seed was harvested, cleaned and cataloged
with a DHS number. Lines with 100 seeds or more were prepared for
nursery evaluation.
[0060] Generation: Doubled haploid evaluation
[0061] Seed Planted: 97DHS-6259 along with the check varieties
46A72 (NS1472), 45A71 (NS1471) and 46A74 (NS2211)
[0062] Seed Harvested: In order to perform quality analysis, twenty
grams of open pollinated seed was harvested from 97DHS-6259. An
equal amount of seed was harvested from the check rows. After
completing the evaluation and finalizing selections, seed was
harvested from the entire row for each selected line including
97DHS-6259.
[0063] Method: Several hundred imidazolinone resistant spring
canola doubled haploid lines, including 97DHS-6259, were planted in
the breeding nursery (project X823A) for evaluation purpose. Each
line was planted in a three meter long row with approximately 100
seeds/row. 46A72 was planted in every 20.sup.th row (#1, 20, 40, 60
etc.) for use as a quality check. 45A71 and 46A74, commercial
imidazolinone resistant varieties from Pioneer Hi-Bred, were
planted as checks in rows, 10, 50, 90 and 30, 70 110 of each range.
The entire nursery was sprayed with ODYSSEY.TM.(a 50/50 mix of
imazethapyr and imazamox) at 30g/ha when plants were at the 4-leaf
stage. A second application of ODYSSEY.TM. (30g/h) was made when
plants were in the rosette stage. Doubled haploid lines showing
herbicide injury were noted. Observations recorded included: days
to flowering, days to maturity, agronomic score at flowering and
agronomic score at maturity. At physiological maturity, lines to be
harvested were selected visually. A 20 g seed sample was harvested
from each of the selected lines. The quality check rows of 46A72
were also harvested. The samples were analyzed in the lab and for
oil percentage, protein percentage, and total glucosinolates using
NIR (Near Infrared Spectroscopy). Final selection of lines was
based on days to maturity, agronomic score at maturity, oil
percentage, protein percentage and total glucosinolates. Several
doubled haploid lines were selected including 97DHS-6259.
[0064] Generation: Greenhouse Pure seed increase
[0065] Seed Planted: 97DHS-6259
[0066] Seed Harvested: 97DHS-6259
[0067] Method: Each selected line including 97DHS-6259, was planted
in the greenhouse (project SN-707) using remnant pure seed. All
lines were sprayed with 60 g/ha ODYSSEY.TM. (2.times.rate) at the
4-leaf stage, in order to confirm imidazolinone resistance. All
lines were inoculated with blackleg (Phoma lingam) spores, to
induce disease development. Lines showing herbicide injury and/or
susceptibility to blackleg were discarded. Selected lines,
including 97SN-6259 were self-pollinated to produce 20g of seed,
and were assigned new code numbers. 97SN-6259 was assigned the
code, NS3801.
[0068] Generation: Field Evaluation (R200 tests)
[0069] Seed Planted: NS3801
[0070] Seed Harvested: NS3801
[0071] Method: The selected lines including NS3801, were evaluated
in a two replicate yield trial (R221) planted at six locations in
western Canada. Plot size was 9 square meters (6 m.times.1.5 m).
The seeding rate was 5.5 kg/ha. Appropriate check varieties were
included in the yield trial. The same entries were planted in a
disease trail where blackleg inoculum was applied to ensure uniform
disease infection. Observations recorded included: days to
flowering, days to maturity, lodging score (1=poor, 9=good), yield
(q/ha), and moisture percentage. At harvest, a 15 gram seed sample
was collected from each plot, and was analyzed to determine oil
percentage, protein percentage, total glucosinolates, and fatty
acid composition.
1TABLE 1 illustrates the performance of Brassica napus variety
NS3801 in comparison to WCC/RRC check varieties. Yield** Yield
Maturity Oil Protein Glucs Blackleg VARIETY (Qu/Ha) (% Chk) (Days)
(%) (%) (uM/g) (1-9)** NS3801 29.60 93.36 102.40 48.29 46.30 13.89
8.44 Defender 29.67 93.80 105.70 48.16 48.14 13.63 6.57 Excel 33.93
107.27 109.50 49.70 47.67 18.08 6.04 Legacy 31.34 99.08 108.40
49.64 48.75 10.90 5.57 Mean of Napus Chks # 31.65 100.05 107.87
49.17 48.19 14.20 6.06 Difference -2.05 -6.69 -5.47 -0.88 -1.89
-0.31 2.38 *Data from Pioneer Hi-Bred Trials in the Short Season
Zone of Western Canada **Trait Definitions: Yield = seed yield in
quintals (decitonnes) per hectare and as percentage of Checks Mean;
Maturity = days from Planting to physiological maturity; Oil &
Protein as percentage of total seed weight at 8.5% moisture; Glucs
= aliphatic glucosinolates in seed at 8.5% moisture, expressed in
micromoles per gram # WCC/RRC Check Varieties for B. napus & B.
rapa. For registration of early B. napus varieties, yield and
composition are Compared to B. rapa, and maturity is compared to B.
napus, where Early Napus = -4 days or more vs. B. napus checks
[0072] Deposits
[0073] This invention is not to be construed as limited to the
particular embodiments disclosed, since these are regarded as
illustrative rather than restrictive. Moreover, variations and
changes may be made by those skilled in the art without departing
from the spirit of this invention.
[0074] The seeds of the subject invention were deposited in the
American Type Culture Collection (ATCC), 10801 University Blvd.,
Manassas, Va. 20110-2209, USA:
2 Seed Accession Number Deposit Date Brassica napus NS3801 PTA-2470
Sep. 14, 2000
[0075] The deposit will be maintained at ATCC, P.O. Box 1549,
Manassas, Va. 201008. Access to this deposit will be available
during the pendancy of the application to the Commissioner of
Patents and Trademarks and persons determined by the Commissioner
to be entitled thereto upon request. This deposit will be
maintained under the terms of the Budapest Treaty on the
International Recognition of the Deposit of Microorganisms for the
Purposes of Patent Procedure. The deposit will irrevocably and
without restriction or condition be available to the public upon
issuance of a patent. However, it should be understood that the
availability of a deposit does not constitute a license to practice
the subject invention in derogation of patent rights granted by
government action or under the Plant Variety Protection Act (7 USC
2321 et seq.).
* * * * *