U.S. patent number PP22,593 [Application Number 12/799,668] was granted by the patent office on 2012-03-20 for stevia plant named `t60`.
This patent grant is currently assigned to SGF Holdings LLC. Invention is credited to Grania Viorela Garnighian.
United States Patent |
PP22,593 |
Garnighian |
March 20, 2012 |
Stevia plant named `T60`
Abstract
A new and distinct Stevia rebaudiana plant named `T60` is
described. The new variety is distinguished from other Stevia
varieties by a high leaf concentration of rebaudioside A; its tall,
bushy nature; its ovate leaves; and its long stem stature.
Inventors: |
Garnighian; Grania Viorela
(Prior Lake, MN) |
Assignee: |
SGF Holdings LLC (Bellingham,
WA)
|
Family
ID: |
44859440 |
Appl.
No.: |
12/799,668 |
Filed: |
April 28, 2010 |
Prior Publication Data
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Document
Identifier |
Publication Date |
|
US 20110271413 P1 |
Nov 3, 2011 |
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Current U.S.
Class: |
PLT/258 |
Current CPC
Class: |
A01H
6/14 (20180501); A01H 5/02 (20130101); A01H
5/00 (20130101) |
Current International
Class: |
A01H
5/00 (20060101) |
Field of
Search: |
;PLT/258,263.1 |
Primary Examiner: McCormick Ewoldt; Susan
Attorney, Agent or Firm: Morrison & Foerster LLP
Claims
We claim:
1. A novel and distinct variety of Stevia plant named `T60` having
the characteristics described and illustrated herein.
Description
Botanical/commercial classification: Stevia rebaudiana L.
Variety denomination: `T60`.
BACKGROUND OF THE INVENTION
Stevia rebaudiana is a shrubby perennial, growing up to 65-100 cm
tall. It is a member of the Compositae family and originates from
Paraguay. This species is grown commercially in Brazil, China,
Paraguay, the United States, and other countries. The plants are
grown so that sweet glycosides present in the leaves can be
extracted for use as sweeteners. The sweetest of these glycosides
is rebaudioside A (Reb A).
The development of new varieties of Stevia rebaudiana with high
levels of Reb A is desirable. The new Stevia variety `T60`
described herein is such a variety.
The new `T60` variety was asexually reproduced from callus through
an in vitro tissue culture technique performed in Woodland,
Calif.
BRIEF SUMMARY OF THE INVENTION
The major characteristics exhibited by the new Stevia variety `T60`
that distinguish it from other varieties include a high
concentration of total glycoside and high concentration of Reb A in
the leaves from total glycoside. Other major characteristics that
also distinguish the new Stevia variety `T60` from other varieties
include a tall, bushy stature that is resistant to high winds;
spatulate-oblanceolate to ovate leaves; high yield foliage
production. For example, `T60` produced over 3000 lbs/acre in one
harvest. Still other major characteristics that distinguish the new
Stevia variety `T60` from other varieties include being virus free,
resistant to Fusarium ssp. and Sclerotinia ssp., drought resistant,
and resistant to compact argilous soils. Another major
characteristic exhibited by the new Stevia variety `T60` that
distinguishes it from other varieties is an average biological
cycle of 90-115 days between 20-27 N,S Latt, giving the option of
secondary harvest per annual cycle.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts a color photograph of a fully mature `T60` stevia
plant near the end of the growing season.
DETAILED DESCRIPTION OF THE INVENTION
Four wild varieties of Stevia were imported from the Paraguayan
government. These varieties were derived from a wild germ plasm in
Paraguay, locally identified as `Criola` material, and released by
the Paraguayan government upon request for research and breeding.
The four imported `Criola` lines were named `IAN-135`, `IAN-142`,
`IAN-228`, and `IAN-259`.
Table 1 depicts the glycoside and Reb A percentages for the
`Criola` lines described above.
TABLE-US-00001 TABLE 1 Plant Length of Flowering Height Leaves
Variety Cycle Days (cm) (cm) IAN-228 Early 110 65 4 IAN-135 Medium
180 82 4 IAN-259 Medium 180 55 5 IAN-142 Late 200 110 6 Width of
Leaves Total Total Reb A to Variety (cm) Glycoside Reb A Glycoside
IAN-228 2 18.47 13.25 71.7% IAN-135 2 16.56 8.06 48.7% IAN-259 2
16.55 11.24 67.9% IAN-142 3 19.06 13.15 69%
As a first step in the production of new Stevia varieties, the four
`Criola` lines were planted in vitro in tissue culture medium. The
tissue culture material was multiplied by successively transferring
plantlets in hormone-supplemented culture. Plantlets of each
variety were planted into 2 inch plugs and then into 4 inch pots
between December of year 1 and January of year 2. The plantlets
were planted in a field in Woodland, Calif. between March and April
of year 2. The plantlets were then allowed to flower, which
occurred between July and August of year 2.
In August of year 2, anthers from the flowered plantlet were
collected before anthesis. Approximately 200 anthers were collected
from plantlets of each of the four `Criola` lines. The anthers were
then plated in vitro to derive haploid lines. The in vitro tissue
culture medium induced callus formation from the plated anthers.
Callus formation was observed in October of year 2. Haploid lines
were created from the formed callus. The process of creating elite
Stevia lines required that the chromosome count of each haploid
line be doubled, since haploid lines cannot survive as plants. The
full complement of chromosomes was regenerated by using successive
colchicine treatments of 20 ppm, 40 ppm, and 60 ppm on both the
callus and the shoots regenerated from the callus.
Every green callus that formed a diploid plantlet was transferred
into a hormone-free medium for multiplication. Multiplication of
the diploid plantlets resulted in the creation of a unique line of
plants with unique characteristics distinguishable form the
original four `Criola` lines. These new Stevia lines were named
T-lines. The T-lines were grown out in 2 inch plugs, then
transferred to 4 inch pots, and then planted in the field in
Woodland, Calif. The selected T-lines were shown to be superior to
the parental stock. The selected T-lines either had higher total
levels of glycoside, or higher levels of Reb A. Based on these
characteristics, all callus material that gave rise to the new
T-lines was collected. Genetically unique lines were developed from
this callus material.
To test for percentage of Reb A production, the new T-lines were
planted from tissue culture into 2 inch plugs and then transplanted
into 4 inch pots. By the age of six weeks, this second generation
of T-line plants had grown to about 10 inches in height in the
pots. At six weeks the T-line plants were sampled to obtain HPLC
data on the percentage of Reb A production. This was done even
though the percentage of glycosides found in the leaf material of
the new T-lines plants would not be as high as expected levels in
mature plants. The levels of Reb A in these new T-line Stevia
plants were as high as 89.2% of total glycoside levels. After the
HPLC data was obtained, the T-line Stevia plants were planted in
the field in Woodland, Calif., and grown to maturity. At maturity,
the production rates of glycosides were evaluated.
All new T-lines were grown out in greenhouses in Woodland, Calif.
for planting in the field, to allow for further testing and
breeding for seed.
Of the new Stevia T-lines, three varieties were selected that
produced high levels of Reb A. The production of high levels of Reb
A in these Stevia T-lines will allow large amounts of Reb A to be
harvested. The present Stevia variety `T60` is one of the three
selected T-lines developed by the methods described herein. The
Stevia variety `T60` was derived from the T-line `T6`. The `T6`
line was derived from `Criola` line `IAN-135`.
Table 2 depicts HPLC data on the percentage of glycoside and Reb A
for samples of the Stevia variety `T60`.
TABLE-US-00002 TABLE 2 Samples of mature Total Total Reb A to `T
60` Stevia plants Glycoside Reb A Glycoside 09-0144 15.18 12.58
82.8% 09-0154 16.96 14.39 84.8% 09-0165 14.58 12.00 82.3% 09-0166
15.05 12.46 82.8%
The HPLC data shows that the average percentage of Reb A to
Glycoside in Stevia variety `T60` was 83.2%. This is an increase of
at least 11.5% over the `Criola` lines. The `T60` variety also
showed an increase of 34.5% over `IAN-135`, from which `T60` is
derived.
DETAILED BOTANICAL DESCRIPTION
The Stevia variety `T60` is a perennial herb with filiform deep
roots. The `T60` variety has a long stem that is on average 65-100
cm tall, erect, hairy, and slender. The stem easily produces
secondary shoots (suckers) from its base, dies off and is renewed
annually. The stem produces an average of 5 to 10 suckers. The stem
also produces numerous lateral branches, thus, forming a
more-or-less roundish and dense crown. The `T60` variety also has
an average biological cycle of 90-115 days. The variety goes
dormant and is renewed annually.
The stem of the `T60` variety produces an average of 3 to 7 lateral
branches. The average length of each lateral branches ranges from
30 to 40 cm. The average diameter of the lateral branches ranges
from 5 to 7 mm. The lateral branches are light green in color (RHS
142A). The lateral branches form a roundish and dense crown.
The crushed leaves exude a strong odor, and all the green parts of
the plant taste sweet. The leaves are simple, opposite and sub
sessile. The internodes have an average length of 2 to 4 cm. The
blades are subcoriaceous, very variable in shape and size, and
ovate. The blades have an average length of 2 to 3 cm and an
average width of 0.6 to 1 cm. The blades are apex obtuse, base
cuneate, margins entire serate on the upper half, three primary
veins arise from the leaf base raised and prominent on the blade's
lower side, immersed on the upper side, and secondary venation
reticulate.
The leaf blades of actively growing plants of the `T60` variety are
light green in color (RHS 142A). In the dry state, the leaf blades
are olive-green to brownish green in color (RHS 147A-147B), and
usually darker on the upper side. Both surfaces are subscabrous
with black glandular dots on the lower side, the leaves sub sessile
or the petiole to 3-4 mm long. The capitula are arranged into
loose, paniculate corymbose inflorescences at the terminal ends of
the branches, and have a peduncle that is on average 1-4 cm long,
and very slender. Pedicels of each capitulum are slender and on
average are 1-4 mm long, bracts are linear-lanceolate, and on
average are 1-2 mm long. Each capitulum is enveloped by an
involucre, and the lower half has a light green color (RHS 142A),
and the upper half has a yellowish (RHS 142C) color. The stems at
maturity are brown-reddish in color (RHS 35A-35B).
The Stevia variety `T60` has 5 phyllaries that are finely hairy,
green (RHS 129B) when fresh, linear to subulate, 4-5 mm long, and
acute to rounded at apex. Each capitulum is made up to 5 disk
florets greenish white (RHS 155C). The seeds are achenes bearing
numerous, equally long pappus awns.
The Stevia variety `T60` expresses high concentrations of total
glycosides, with a total of rebaudioside A concentration of greater
than 80%. The Stevia variety `T60` has an average biological cycle
of 90-115 days.
* * * * *