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.

Wheat breeding.

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.

Disease problems.

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.

Ownership of germplasm?


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.