KS95WGRC33 Septoria leaf blotch-resistant germplasm released.
T.S. Cox, W.W. Bockus, B.S. Gill, R.G. Sears, W.F.
Heer, J.H. Long, and T.L. Harvey.
In 1995, the Agricultural Research Service, U.S.
Department of Agriculture, and the Kansas Agricultural Experiment
Station announced the release of KS95WGRC33 hard red winter wheat
germplasm for breeding and experimental purposes.
Plants of KS95WGRC33 (tested as experimental line
KS94U331) are resistant to Septoria leaf blotch (caused by S.
tritici Roberge ex Desmaz.), when inoculated as seedlings
in the greenhouse and under natural infection in the field. The
pedigree of KS95WGRC33 is KS93U69*2/TA 2397. KS93U69 is a sister
line of KS90WGRC10 (TAM 107*3/TA 2460), and TA 2397 and TA 2460
are accessions of T. tauschii (Coss.) Schmal. collected
near Sisiar, Afghanistan, and Khoshyailagh, Iran, respectively.
The leaf-blotch resistance of KS95WGRC33 is derived from TA 2397;
KS95WGRC33 also carries the gene Lr41 for resistance to
leaf rust (caused by P. recondita Roberge ex Desmaz.) from
TA 2460 via KS93U69. When inoculated in seedling experiments
with a field-collected isolate of S. tritici from Riley
Co., Kansas, KS95WGRC33 had 4 % of its leaf area infected with
compared with 28 % for KS93U69, 41 % for TAM 107, and 29 % for
Karl 92, the resistant check cultivar. Preliminary monosomic
analysis indicates that its resistance to leaf blotch is conditioned
by a gene on chromosome 1D.
Under heavy natural infection by S. tritici
at Parsons, Kansas, in 1993 and 1994, KS95WGRC33 had significantly
longer duration of green leaf-area than KS93U69, TAM 107, and
Karl 92. In 1995, a heavy combined infection of leaf blotch,
leaf rust, glume blotch [caused by Stagonospora nodorum
(Berk.) Castellani & E.G. Germano], and tan spot [caused by
Pyrenophora tritici-repentis (Died.) Drechs] occurred at
Parsons, Hutchinson, and Manhattan, Kansas. At all locations,
KS95WGRC33 had green leaf-area duration equal to that of Jagger,
the resistant check cultivar for all four diseases. In seedling
tests, KS95WGRC33 has exhibited significantly less infection by
nodorum blotch and tan spot than has its recurrent parent, TAM
107, and is moderately resistant to cultures of wheat curl mite
[Eriophyes tulipae (Keifer)], to which TAM 107 is susceptible.
Otherwise, KS95WGRC33 is similar to TAM 107 in days to heading,
plant height, and general phenotype.
Small quantities (2 grams) of seed of KS95WGRC33
are available upon written request. Appropriate recognition of
source is requested when this germplasm contributes to research
or development of a new breeding line or cultivar. Seed stocks
are maintained by T.S. Cox (USDA-ARS), Wheat Genetics Resource
Center, Department of Agronomy, Throckmorton Hall, Kansas State
University, Manhattan, KS 66506-5502, USA.
R.G. Sears, T.J. Martin, and T.S. Cox.
Two new hard red winter wheat varieties have been
released recently by the Kansas Agricultural Experiment Station.
`Jagger' (KS82W418/Stephens)
is a new hard red winter wheat variety developed cooperatively
by the Kansas Agricultural Experiment Station and the Agricultural
Research Service, United States Department of Agriculture. Jagger
was named after the late Joe Jagger, a long-time wheat producer
and leader in Kansas agriculture. Joe Jagger dedicated his life
to growing and promoting high quality wheat. He was fascinated
with wheat, its growth and development, harvest, and utilization.
The Jagger farm was home of the county variety demonstration
plots for a record 75 years.
Jagger represents substantial improvements in grain
yield, disease resistance, and baking quality, compared to popular
wheat varieties such as Karl, Tam 107, and 2163 and is anticipated
to replace these varieties over the next several years. Jagger
is an awned, bronze-chaffed, semidwarf that is very early in maturity.
Jagger has excellent straw strength and stands well under most
Kansas growing conditions. The cultivar is resistant to aluminum
toxicity caused by low soil pH.
Jagger is resistant to prevailing races of stem
rust and leaf rust, soilborne mosaic virus, spindle streak mosaic
virus, tan spot, and speckled leaf blotch. Jagger is moderately
resistant to glume blotch, bacterial streak, cephalosporium stripe,
and wheat streak mosaic virus, but is susceptible to powdery mildew.
Jagger is susceptible to the Hessian fly, green bug, and Russian
wheat aphid.
Jagger is well adapted across all growing areas
of Kansas, having excellent disease resistance for the central
and eastern growing areas and good wheat streak mosaic virus tolerance
and drought tolerance for the western areas of the state. Because
of concerns about Jagger's winterhardiness, it is being
recommended currently for areas south of 38_Lat N. Milling quality
of Jagger is average. Baking quality is very good. Jagger's
protein levels are comparable to those of the high protein variety
Karl.
`2137' is a new hard red winter
wheat variety developed cooperatively by the Kansas Agricultural
Experiment Station and the Agricultural Research Service, United
States Department of Agriculture. 2137 was selected as an F4
head row from the cross `W2440/W9488//2163', where
W2440 = `Sturdy//Coker68-15/MOW7510/3/Tam W-101';
W9488 = `IN4946A-18-2/MOW7718 /3/Sturdy/Kaw', and
2163 = `IN4946A/MOW7470/3/NB/SRW//SRW'. 2137 was
selected originally by wheat breeders at Pioneer Hi-Bred International,
Inc. working at Hutchinson, KS, in 1988. In 1990, Pioneer decided
to close its hard red winter wheat breeding station and donated
the fixed lines and developing germplasm to Kansas State University.
2137 was released to replace 2163 in all areas of Kansas. The
cultivar represents improvements over 2163 for grain yield, test
weight, flour yields, and leaf rust resistance.
2137 is a white-chaffed, semidwarf, with medium
maturity, excellent straw strength, and winterhardiness comparable
to that of either 2163 or Newton. The cultivar is tolerant to
aluminum toxicity caused by low soil pH.
2137 is resistant to wheat soilborne mosaic virus,
wheat spindle steak mosaic virus, and Hessian fly and has good
tolerance to leaf rust, speckled leaf blotch, glume blotch, powdery
mildew, and tan spot. 2137 is moderately susceptible to stem
rust, wheat streak mosaic virus, and barley yellow dwarf virus.
2137 is adapted to all areas of the state, especially
areas where 2163 has done well and is being grown currently.
2137 has performed best in central, north central, and western
Kansas. 2137 is extremely susceptible to Fusarium head scab,
and producers should avoid corn rotations in northeastern Kansas.
2137 has average protein concentration, comparable
to that of 2163; medium to mellow mixing time and tolerance; and
acceptable hard wheat milling characteristics. The cultivar's
baking properties have been rated average, but acceptable by the
Wheat Quality Council in 1993-94 small-scale tests.
R.G. Sears, T.J. Martin, and T.S. Cox.
Heavy disease losses were experienced by Kansas wheat
producers during the past 7 years. Leaf rust, Septoria(s), and
tan spot have caused a significant amount of that damage. Leaf
rust continues to be a major problem because of the pathogen's
genetic diversity in this region and the lack of a stable combination
of disease-resistance genes. Effective resistance in varieties
has been averaging approximately 4 years during the past decade.
We have been extremely reluctant to utilize the
Lr13-34+ complex of genes that has been so effectively
utilized by CIMMYT and other spring wheat breeders around the
world. Leaf rust overwinters on seedling wheat in the southern
Great Plains, because large areas are planted very early to utilize
wheat pasture. Heavy inoculum pressure can develop on seedling
wheat containing the Lr13-34+ resistance. We are concerned
that this unique environment could place additional strong selection
pressure on this combination of leaf rust resistance genes. In
addition, the southern Great Plains represents a geographic block
between spring wheat growing regions in northern Mexico and the
northern Great Plains and Canada, all of which strongly utilize
the Lr13-34+ form of resistance. For these reasons, we
continue to search actively for other gene combinations that will
be more stable and effectively reduce leaf rust losses.
Septoria leaf spot (S. triticii), Septoria
glume blotch (Phaeosphaeria nodorum), and tan spot (Phrenophora
trichostoma) continue to cause more and more damage to wheat
crops grown in the region. We believe this increase was caused
partly by higher rainfall during the past several years. However,
a more significant cause is the shift by farmers to reduced tillage
operations, which has left more straw on the soil surface to protect
the soil from both wind and water erosion. This management shift
has greatly increased the inoculum levels for these diseases and
has resulted in a dramatic shift in varieties planted. Successful
wheat varieties grown in Kansas and the southern Great Plains
will increasingly require high levels of Septoria and tan
spot resistance.
R.G. Sears, T.S. Cox, B.S. Gill, and T.J. Martin.
The Wheat Genetics Resource Center has been outspoken
in regard to concerns about Intellectual Property Rights and the
possible effects of placing restrictions on germplasm exchange
among wheat breeders and geneticists. Administrators in many organizations
are signing agreements and authorizing policy that we feel could
impact, or already is impacting how breeders and geneticists have
traditionally shared and exchanged germplasm. Below is a statement
concerning the problem that we share for use by anyone who agrees
with these issues. We encourage everyone who is concerned with
these issues to speak out and share these or other statements
regarding germplasm with administrators. We also encourage everyone
to share a copy of the Wheat Breeders Code of Ethics with administrators
(The Code is printed in this and every volume of AWN).
The code of ethics is, in fact, a Material Transfer Agreement
(MTA) that addresses the rights of developing breeders and institutions
without restricting crossing. We think it is an excellent document
that has not been shared with enough people. If you agree with
us regarding the trends that are occurring regarding germplasm
issues, please share these statements along with the Wheat Breeders
Code of Ethics with those who would restrict germplasm exchange.
Plant improvement has been evolving since humans
first began to cultivate crops an estimated 10,000 years ago.
Although the methods of crop improvement have changed, the principal
methods driving the process has not. Since plant breeding began,
plant breeders have freely exchanged genetic material, and during
the past 100 years, they have made crosses with that material
to make improvements. The exchange of parental stocks and other
germplasm to use as parents in crossing programs is the primary
and key principle for success in plant improvement. Another important
spin-off also evolved because of open germplasm exchange. As
plant breeders exchange material with others, they develop closer
personal ties, often resulting in lifelong associations that might
not have formed were germplasm exchange just a business deal.
International screening nurseries, which have been extremely
useful as vehicles for germplasm exchange, also have brought the
world's plant breeders closer together. For these reasons,
plant breeders almost unanimously agree that free exchange of
germplasm is one of the most important activities involved in
plant improvement.
Germplasm exchange and the respect for intellectual
property rights (IPR) only recently have become complicated.
Historically, breeders have exchanged genotypes, but the real
purpose was to exchange gametes. Codes of ethics and various
forms of IPRs existed to protect specific genotypes, but almost
always those genotypes have been available for crossing purposes.
Breeders treated IPRs as readers treat books. The genotype or
variety is comparable to a book, which is unique and may be copyrighted.
However, the words in the book, like gametes or genes, can be
rearranged to create something entirely different and are held
in common by all the speakers of the language. IPRs should protect
the book (genotype), but rights to the words (or gametes) should
be held in common with everyone involved in plant improvement.
The UPOV treaties of 1960 and 1991 provide patent-like
protection for varieties, but at the same time allow crossing
among protected strains. This concept allows for two extremely
important principles: 1) it allows unique combinations of genes
to be protected, thus allowing the discoverers proper credit or
opportunity to make a profit, but at the same time not restricting
exchange of germplasm or crossing with that germplasm, which is
so vital in crop improvement and 2) by allowing crossing, it removes
the burden of placing monetary value on the potential combination
of gametes (genes) themselves. Attempting to place a monetary
value on the collective germplasm is analogous to placing value
on the words in books; both would be philosophically indefensible
and logistically unmanageable.
As a community of wheat breeders and geneticists,
we are asked, or in some cases forced, to accept agreements that
would restrict or control germplasm exchange. By approving restrictions,
as a group of scientists, we are approving the concept of placing
a value on germplasm and gametes. We feel this is wrong and a
very dangerous precedent. These requests are basically coming
from administrators struggling with declining budgets. They are
not advocated universally by plant breeders. If organizations
are allowed to restrict or control germplasm exchange through
MTAs, we are sending the message to administrators that we endorse
the concept. It is the wrong message to send. As a community
of plant breeders, we all recognize the value of germplasm exchange.
We must work to protect that principle. By allowing germplasm
exchange with restricted access (via an MTA), we would be removing
a stigma from germplasm commercialization, making it easier for
administrators to follow that road. It would be one giant step
toward closing down the exchange of germplasm that has kept plant
breeding so effective.
The value of a genotype can be estimated. The value
of germplasm is the collective gene pool it represents. It is
virtually impossible to accurately access the value of germplasm.
Specific genes could have little value today, but be extremely
important a decade later. If we begin placing restrictions and
value on germplasm, where do we draw the line? Plant breeding
is largely a process that evolves over many years, with many contributors
to each success. Each unique genotype has a long and complicated
pedigree. Where do you begin to establish value? We need to
rethink the positions that have been taken on germplasm. A value
can be placed on a specific genotype, but the genes that collectively
make up that genotype existed before the first experiment station,
or the first seed company, or even the first human being, and
they are priceless. As a community of scientists, we should strive
to support laws such as the UPOV convention that protect the genotypes
and keep the gametes and genes free for further exploration and
recombination. Continued progress in plant improvement depends
on it.