GrainGenes

Control of rusts and smuts in the western United States, 1995.

Roland F. Line and Xianming Chen.

Models developed for predicting stripe rust, when used in combination with monitoring data, accurately forecasted stripe rust for the 17th consecutive year. In general, the weather in the Pacific Northwest was moderately favorable for stripe rust and leaf rust in 1995. Stripe rust was most severe on Hatton and Weston hard red winter wheat cultivars and on Moro, Tres, and Tyee club wheats in north central Oregon and in south central and central Washington . Losses caused by stripe rust in those regions ranged from 5 % to more than 20 % depending upon the susceptibility of those cultivars. Stripe rust was most severe in fields planted early in the fall of 1994. In general, wheat yields in those regions were better than normal because of higher than normal precipitation during the spring of 1995. However, the yields would have been greater if the rusts were controlled. The highly effective, high-temperature, adult-plant resistance to stripe rust prevented losses in the soft white winter and spring wheat growing zones of Washington, Oregon, and northern Idaho. Losses caused by rusts in northwestern Washington, where the weather is always favorable for stripe rust and leaf rust, exceeded 20 %.

Barley stripe rust, which was introduced into North America from Europe by way of South America and Mexico in 1991, has spread north and west from Texas to northwestern Washington. The barley stripe rust and wheat stripe rust pathogens are related closely but are different forms. Wheat stripe rust can attack some barley cultivars, and barley stripe rust can attack some wheat cultivars. Fifty-six races of the wheat stripe rust pathogen and 14 races of the barley stripe rust pathogen have been identified. The most prevalent wheat stripe rust races in 1995 were those that are virulent on Moro, Tyee, Tres, Weston, Hatton, and Owens; seedlings of Stephens, Madsen, and Hyak; and cultivars from other regions of the United States.

Several new cultivars with superior stripe rust resistance were released, and additional information on new stripe rust resistance genes were determined. Genes for race-specific resistance to stripe rust have been located on 17 of the 21 chromosomes in wheat. High-temperature, adult-plant resistance to stripe rust, which is nonspecific, continues to be the most effective and durable type. However, individual genes for high-temperature, adult-plant resistance are harder to identify and transfer into new cultivars. Molecular markers associated with high-temperature, adult-plant resistance genes in Stephens and resistant F5 progeny from crosses with Stephens show possibilities as tools for identifying plants with high-temperature, adult-plant resistance. Selection for the linked markers associated with the genes should be easier and faster than screening for high-temperature, adult-plant resistance by field testing advanced generations of large populations.

Each year, we evaluate cultivars and breeding lines developed in the western United States for resistance to stripe rust. Currently, all of the major soft white winter wheat cultivars and spring wheat cultivars grown in the Pacific Northwest have high-temperature, adult-plant resistance, and their resistance has remained durable against all North American races of stripe rust. As part of an ongoing program, entries in the National Small Grain Germplasm Collection are being evaluated for high-temperature, adult-plant resistance in the field at Mt. Vernon and Pullman, WA, and in the greenhouse for specific resistance to stripe rust races CDL-17; CDL-20, CDL-25, or CDL-37; CDL-27 or CDL-45; and CDL-29 or CDL-43. The selected races include all of the virulences that have been identified in North America.

Fungicides are being used to determine the effects of stripe rust, leaf rust, stem rust, powdery mildew, and Septoria on yield and are being evaluated for control of the diseases. Spraying with Bayleton, Tilt, Folicur, or several new fungicides at various rates and schedules controlled the rusts in 1995. Treatment of seed with Baytan is part of the integrated rust control program. Treatment of seed with Dividend is being used to control dwarf bunt and other smuts. Raxil is now registered for use in the United States.

A computerized system for managing rusts and other diseases of wheat developed for the Pacific Northwest is being distributed by Cooperative Extension at Washington State University. The program is referred to by the acronym MoreCrop (Managerial Options for Reasonable Economical Control of Rusts and Other Pathogens). MoreCrop predicts diseases and provides information, options, and suggestions to help the user make decisions regarding management of the wheat diseases in the Pacific Northwest. Diseases are predicted based on geographical regions, agronomic zones, crop managerial practices, cultivar characteristics, prevailing weather, and past crops and diseases. MoreCrop currently is being modified to make it even more effective and is being expanded to other regions. The system is distributed at cost ($40 US) by Washington State Cooperative Extension. MoreCrop can be obtained by sending orders for MCP22 MoreCrop, to Bulletin Office, Cooper Publication Building, WSU, Pullman, WA 99164-5912 USA.

Publications.

Chen XM and Line RF. 1995. Gene action in wheat cultivars for durable high-temperature adult-plant resistance and interactions with race-specific, seedling resistance to stripe rust caused by Puccinia striiformis. Phytopath 85:567-572.

Chen XM and Line RF. 1995. Gene number and heritability of wheat cultivars with durable, high-temperature, adult-plant resistance and race-specific resistance to Puccinia striiformis. Phytopath 85:573-578.

Chen XM, Line RF, and Leung H. 1995. Virulence and polymorphic dna relationships of Puccinia striiformis f. sp. hordei to other rusts. Phytopath 85:1335-1342.

Chen XM, Line RF, and Jones SS. 1995. Chromosomal location of genes for resistance to Puccinia striiformis in winter wheat cultivars Heines VII, Clement, Moro, Tyee, Tres, and Daws. Phytopath 85:1362-1367.

Chen XM, Line RF, and Jones SS. 1995. Location of genes for stripe rust in spring wheat cultivars Compair, Fielder, Lee, and Lemhi and interactions of aneuploid wheats with races of Puccinia striiformis. Phytopath 85:375-381.

Line RF. 1995. Control of rusts and smuts in western United States, 1994. Ann Wheat Newslet 41:312-315.

Line RF. 1995. MoreCrop, an expert advisory system for wheat disease forcasting and management. In: Highlights of Research Progress, Washington State Univ, Dept Crop Soil Sci TR95-3:66-70.

Line RF. 1995. Control of stripe rust, leaf rust, and stem rust, 1995. In: Highlights of Research Progress, Washington State Univ, Dept Crop Soil Sci TR95-3:74-78.

Line RF. 1995. Stripe rust resistance, a major component of the integrated management of wheat diseases and a basis of sustainable wheat production. In: Highlights of Research Progress, Washington State Univ, Dept Crop Soil Sci TR95-3:83-86.

Line RF and Chen XM. 1995. Successes in breeding for and managing durable resistance to wheat rusts. Plant Dis 79:1254-1255.

Line RF and Chen XM. 1995. Barley stripe rust in the Pacific Northwest in 1995. In: Highlights of Research Progress, Washington State Univ, Dept Crop Soil Sci TR95-3:74-78.

Line RF and Qayoum A. 1995. Control flag smut of wheat with seed treatments, 1994. Fungicide and Nematicide Tests 50:316.

Line RF and Qayoum A. 1995. Control of seedborne and soilborne common bunt with seed treatments, 1994. Fungicide and Nematicide Tests 50:315.

Sitton J, Wiese M, Goates B, Forster R, Line R, Mathre D, Peterson C, Smiley R, and Waldher J. 1995. Dwarf bunt of winter wheat in the northwest. PNW Ext Pub 489. 8 pp.

Yildirim A, Jones SS, Murray TD, Cox TS, and Line RF. 1996. Resistance to stripe rust and eyespot diseases of wheat in Triticum tauschii. Plant Dis (Accepted)

Winterhardiness in wheat.

M.K. Walker-Simmons, E. Storlie, L.D. Holappa, S. Verhey, and E. Cudaback.

An estimated 70 % of present acreage in Washington is planted in wheat varieties that are vulnerable to cold injury. Daws and Eltan are two of the most winter-hardy winter wheat varieties grown in the Pacific Northwest. A freezing simulation test is being developed by Eric Storlie to assess winterhardiness of advanced lines with the same type of tolerance as Daws and Eltan. Testing of molecular markers associated with winter hardiness also is being initiated.

Cold temperature and dehydration-responsive genes in wheat. In wheat, we have identified a novel protein kinase mRNA, PKABA1, that accumulates in embryos treated with ABA and in dehydrated or cold-treated seedlings. The accumulation of PKABA1 mRNA may be part of the initial stress responses to weather-related stress that ultimately result in the acquisition of stress tolerance. The PKABA1 transcript accumulates rapidly within 2 hours following dehydration and in response to cold and salt treatment. High PKAB1 mRNA levels are detected in field-grown plants growing under cold winter conditions, but not under warmer summer temperatures. A second protein kinase gene called TaPK3, which is a genomic clone, has now been cloned. Sequence analysis has shown considerable sequence similarity to SNF1 protein kinase genes associated with nutrient stress responses. The kinase protein has been expressed in a recombinant gene expression system using a pET vector system. The expression studies are aimed at identifying the protein targets of the kinase enzyme during weather-related stress.

Publications.

Holappa LD and Walker-Simmons MK. 1995. A wheat ABA-responsive protein kinase mRNA, PKABA1, is upregulated by dehydration, cold temperature and osmotic stress. Plant Physiol 108:1203-1210.

Abrams SR, Rose PA, and Walker-Simmons M.K. 1995. Structural requirements of the ABA molecule for maintenance of dormancy in excised wheat embryos. In: Plant Dormancy: Physiology, Biochemistry, and Molecular Biology (Lang G ed). CAB International (In press).

Walker-Simmons MK and Goldmark PJ. 1995. Characterization of genes expressed when dormant seeds of cereals and wild grasses are hydrated and remain growth arrested. In: Plant Dormancy: Physiology, Biochemistry, and Molecular Biology (Lang G ed). CAB International (In press).

Rose PA, Cutler AJ, Lei B, Shaw AC, Barton DL, Loewen MK, Abrams SR, and Walker-Simmons MK. 1995. A methyl ether derivative of ABA exhibits selective activity in various assays. 15th Inter Conf Plant Growth Substances. Abstr 256.

USDA-ARS Western Wheat Quality Laboratory.

Craig F. Morris, Director.

ARS Staff: H.C. Jeffers, A.D. Bettge, D. Engle, M.L. Baldridge, B.S. Patterson, and R. Ader.

WSU staff: G. King and B. Davis; postdoctoral, M. Giroux; visitors: Byung Hee Hong (S. Korea) and Brenda Shackley (Australia).

The Western Wheat Quality Lab (WWQL) is one of four regional USDA wheat quality labs devoted to enhancing wheat quality through the cooperative development of new wheat cultivars and fundamental and applied research.

The primary effort remains the evaluation of milling, baking, and end-use qualities of breeders' lines. Research continues to examine the control of endosperm texture and starch pasting quality. The second annual PNW Wheat Quality Council meeting was held in Park City, UT, and was a tremendous success. We will soon have a home page operational on the World Wide Web, the site address is: http://www.wsu.edu:8080/~wwql/.

Publications.

Bettge AD, Morris CF, and Greenblatt GA. 1995. Assessing genotypic softness in single wheat kernels using starch granule-associated friabilin as a biochemical marker. Euphytica 86:65-72.

Greenblatt GA, Bettge AD, and Morris CF. 1995. The relationship between endosperm texture and the occurrence of friabilin and bound polar lipids on wheat starch. Cereal Chem 72:172-176.

Morris CF. 1995. Breeding for end-use quality in the Western U.S.: A cereal chemist's view. In: Cereals '95. Capturing the Benefits of Research for Consumers (Williams YA and Wrigley CW eds). Proc 45th Aust Cereal Chem Conf, Royal Aust Chem Inst, North Melbourne, Victoria, Australia. pp. 238-241.

Peterson Jr. CJ, Allan RE, Morris CF, Miller BC, Moser DF, and Line RF. 1995. Registration of `Rod' wheat. Crop Sci 35:593.

Morris CF and Rose SP. 1996. Chapter 1. Quality requirements of cereal users. Wheat. In: Cereal Grain Quality (Henry RJ and Kettlewell PS eds). Chapman & Hall, London.

Wrigley CW and Morris CF. 1996. Chapter 11. Breeding cereals for quality improvement. In: Cereal Grain Quality (Henry RJ and Kettlewell PS eds). Chapman & Hall, London.

Ammar K, Kronstad WE, and Morris CF. 1995. Breadmaking quality of durum wheat and its relationship with gluten protein composition. Agron Abstr p. 140.

Bettge AD and Morris CF. 1995. Flour hydration capacity related to grain hardness and solution pH. Cereal Foods World 40:659. (Abstract 125.61)

Morris CF. 1995. Starch-protein-lipid interactions and wheat grain hardness. Cereal Foods World 40:676. (Abstract 219)

DeMacon VL. 1995. Loss of seed dormancy and the relationship between dormancy and embryo culture in wheat (Triticum aestivum L.). MS thesis, Washington State Univ.

Zeng M. 1996. Sources of variation for starch gelatinization, pasting and gelation properties in wheat. MS thesis, Washington State Univ.