OREGON

OREGON STATE UNIVERSITY

Department of Crop and Soil Science, Corvallis, OR 97331-3002 USA.

J.P. Bassinette, R.S.Karow, D.K. Kelly, R.W. Knight, W.E. Kronstad, M.J. A. Larson, M.D. Moore, S.E. Rowe, and M.C. Verhoeven.

Production.

The 1994-95 crop year was one of contrasts. After one of the driest autumns on record, the cropping season had an above-average rainfall. Tens of thousands of acres of winter wheat could not be seeded, because of wet field conditions. Spring wheat acreage jumped from 58,000 harvested acres in 1994 to 114,000 in 1995. Normally, such an increase in spring acreage would result in decreased overall production, but spring and summer rains lead to higher yields in both winter and spring wheats. Total 1995 acreage was 939,000 acres, with an average yield of 67.8 bu/acre. Although high rainfall was beneficial to eastern Oregon dryland crops, western Oregon farmers encountered unexpected problems with takeall and other diseases because of the rains. Protein levels in soft white wheat varied by region, but were generally at acceptable levels (< 10.5 %).

`Stephens' remains the dominant variety in the state. The Oregon Agricultural Statistics Service estimated Stephens acreage at 56.5 % of total wheat acreage in 1995. The winter wheats Madsen (12.2 %) and `Gene' (6.6 %) and the soft white spring wheat `Penawawa' (7.4 %) are the only other varieties to occupy more than 5 % of state acreage.

Agronomic research being conducted in the state includes Septoria tritici and Septoria nodorum management trials, nitrogen management trials in both eastern and western Oregon, seed treatment evaluations, and numerous weed control studies.

Wheat breeding and genetics.

The 1995 crop year saw a large increase in experimental plot acreage. The acreage of material at our major testing sites increased from 26 to 41 acres. The reason for this was twofold. First, the method of handling segregating material changed. Prior to 1995, all F4 and F5 populations were the result of bulked heads. In 1995, the heads pulled from F3s and F4s were maintained as head rows and became the F4 and F5 head rows. Thus, where once three rows, 20 feet long, represented a selection, now there were 12 to 14 head rows, each 10 feet long. Second, the hard white winter portion of the program had grown considerably and crosses made specifically for that category were now entering the F4 and F5 stages of development, which further added to the increase in acreage.

In 1995, two new people came on the project: John Bassinette, who received his Master's degree in agronomy at the University of Idaho, and Mark Larson, who is working on his Master's degree in plant breeding and genetics at Oregon State University. John is primarily responsible for agronomic and special studies. In the fall of 1995, a bunt nursery was established at Pendleton, a winterhardiness nursery was planted on a north slope near Pendleton, and two winter durum trials to determine optimum fertilizer and seeding rate also were established at that site. Mark Larson's primary responsibility is with the international aspect of the program. He must oversee the selection, harvest, and distribution of The International `Spring x Winter' Screening Nursery. He also is in charge of our cooperative effort with Turkey/CIMMYT for sending out the FAWWON to the US and Canadian cooperators. As well as handling the international aspects of the program, Mark plays a major role in the computerized database management of all our field books and data.

Mike Moore, who previously held John Bassinette's position, is now at the Columbia Basin Agricultural Research Center. There he has assumed interim responsibility for the club wheat breeding program. This program, once independent of the wheat breeding and genetics program at Corvallis, has come under its mantle. Last season the majority of the club wheat crosses were made in Corvallis under Dr. Kronstad's direction. The segregating material was sent to Mike for screening in its area of adaptation. Mike and his crew also are responsible for Russian wheat aphid screening and for field assistance at the Pendleton screening site.

For the past 2 years, under the auspices of the USDA and USAID, the project has developed ties with cereal breeding personnel and institutes in the Baltic countries of Latvia, Lithuania, and Estonia. Six breeders from these countries came for the harvest in 1994. In June of 1995, a symposium was held in Riga, Latvia (Baltic States Cereal Breeders and Producers Symposia). In July of 1995, another wheat breeder, Vija Strazdina, also from Latvia, came to Oregon to make selections for her program.

Publications.

Mou B and Kronstad WE. 1994. Duration and rate of grain filling in selected winter wheat populations: I. Inheritance. Crop Sci 34:833-837.

Mou B, Kronstad WE, and Saulescu NN. 1994. Grain filling parameters and protein content in selected winter wheat populations: II. Associations. Crop Sci 34:838-841.

Costa JM and Kronstad WE. 1994. Association of grain protein concentration and selected traits in hard red winter wheat populations in the Pacific N.W. Crop Sci 34:1234-1239.

Saulescu NN and Kronstad WE. 1995. Detection of genotypic differences in early growth response to water stress in wheat using the snow and tingey system. Crop Sci 35:928-931.

Saulescu NN and Kronstad WE. 1995. Growth simulation outputs for detection of differential cultivar response to environmental factors. Crop Sci 35:773-778.

Camacho-Casas MA, Kronstad WE, and Scharen AL. 1995. Septoria tritici resistance and associations in a wheat cross. Crop Sci 35:971-976.


SOUTH DAKOTA

SOUTH DAKOTA STATE UNIVERSITY, AND USDA-ARS NORTHERN GRAIN INSECT RESEARCH LABORATORY (NGIRL)

Plant Science and Biology/Microbiology Departments, Brookings, SD 57007, USA.

Personnel changes.

Dr. Yue Jin joined the faculty of the Plant Science Department as an assistant professor of plant pathology. Dr. Jin received an M.S. degree in applied statistics from the Department of Statistics and M.S. and Ph.D. degrees in plant pathology from the Department of Plant Pathology at North Dakota State University. Following graduate studies, he remained at NDSU as a postdoctoral fellow, conducting research on sources of resistance to leaf and stem rust in barley, biology of barley crown rust, and pathogenic variation in the crown rust complex. His research efforts at SDSU will focus on epidemiology and control of fungal diseases of small grain cereals, with primary emphasis on diseases of spring and winter wheat.

Dr. C.H. Chen has retired after 29 years at South Dakota State University in the Biology/Microbiology department. In recent years, his research has focused on the development and improvement of a wheat anther culture system for spring wheat.

Dr. Don Kenefick retired from service to the Plant Science Department, effective September 1995. For nearly 36 years, Dr. Kenefick worked diligently to characterize physiological mechanisms associated with winter freeze stress.

Dr. Robert Kieckhefer retired from service to the USDA-ARS Northern Grain Insects Research Laboratory, effective January 1996. Dr. Kieckhefer was recognized widely as an authority on cereal aphid biology and ecology and was instrumental in characterizing yield loss-thresholds for cereal aphid infestations in the northern Great Plains. This research formed the basis for integrated pest management (IPM) strategies and programs currently used across this region for effective cereal aphid management.

Spring wheat breeding.

J.C. Rudd, B.G. Farber, C.H. Chen, S.S.A. Rizvi, Y. Jin, R. Yu, F. Aldana, K.R. Ruden, and S. Zhu.

Production. The 1995 production of Hard Red Spring Wheat in South Dakota was 33.6 million bushels from 1.2 million acres. The harvested acreage is 39 % less than that in 1994 and is the lowest since 1972. The average yield was 28 bu/acre, which is equal to the 5-year average. Because of a cool, wet spring, most of the spring wheat was planted late and many fields were never planted. Only 50 % of the acreage was planted by 20 May, as compared to the 5-year average of 20 April. Considering the late planting, yields were better than expected. Yield loss because of disease appeared to be less than the losses reported in 1993 and 1994. Durum production in the state was 896,000 bushels from 32,000 acres, with an average grain yield of 28 bu/acre.

New Release. `SD0010' hard red spring wheat is being released as `Oxen'. Originating from Pioneer Hi-bred International, the name Oxen was chosen to symbolize the success attainable when public and private industry work together as a `team'. The Pioneer designation of SD0010 is SBF0089 from the cross `SBY336A/SBZ004A'. The pedigree of SBY336A is `Waldron//Lundi/Justin/3/Arg 5/4/Pioneer line W6744' and the pedigree of SBZ004A is `Pioneer Variety 2369/Len'. Oxen is anticipated to be submitted for cultivar protection under the Plant Variety Protection Act, and Title V of the Federal Seed Act. Oxen is an awned, early maturing, semidwarf, hard red spring wheat. In comparison to 2375, SD0010 is higher yielding, similar in maturity, slightly shorter, better in straw strength, and less prone to shattering. Bushel weight is less than that of 2375, but greater than that of Prospect. Oxen appears to be widely adapted and has performed well in all areas tested in South Dakota, Minnesota, and North Dakota. Oxen is resistant and moderately resistant to the prevalent races of leaf rust and stem rust, respectively. Based on performance data, the Fusarium head blight resistance of Oxen is similar to that of Butte 86 and slightly less than that of 2375. SD0010 is a strong mixing wheat with medium protein content. Protein content is similar to 2375 and Butte 86. The milling and bread-making qualities of Oxen are equal to those of Grandin (1994-95, Wheat Quality Council, Hard Spring Wheat Technical Committee).

High temperature tolerance. A genetic study of high temperature tolerance in spring wheat was completed this year. This was a joint study with CIMMYT and involved growth chamber studies and field trials in South Dakota, USA, and Obregon, Mexico. The heritability of yield components was more stable than the heritability of yield or any of the calculated heat stress indexes. At each planting date-location, the wheat was stressed at different growth stages. The genotype that could best tolerate or compensate for the stress at that growth stage yielded better at that particular site. High temperature tolerance was concluded to be related to the growth stage in which the stress occurs, i.e., the capacity for yield component production was more heritable than yield or heat tolerance. (F. Aldana, J.C. Rudd)

Fusarium head blight screening. With the objective of developing a greenhouse technique to screen large numbers of segregating populations, various inoculation techniques were compared for accuracy and efficiency. The techniques compared were single-floret inoculation, mass spray, and inoculation with colonized seed. For all treatments, the plants were grown in soil-beds, and misting was provided for 30 seconds every 2 hours from the time of the first inoculation until the last symptoms were recorded. The single-floret inoculation method was the most precise method used and consisted of placing a single drop of inoculum in the central floret of each spike at anthesis and recording disease symptoms 14 and 21 days after inoculation. Although the single-floret inoculation method works very well, it is time-consuming and, thus, the number of lines that can be evaluated is limited. With the mass spray technique, the plants were sprayed with a spore suspension beginning at anthesis of the earliest genotype and continuing three times per week until disease symptoms were recorded on the latest-maturing genotype. Inoculum was provided in the third method by spreading colonized seed in the greenhouse beds at weekly intervals. For the mass-inoculation treatments, visual symptoms were recorded 21 days after anthesis of the particular genotype. The symptoms produced by the mass inoculation were correlated highly with the symptoms from the single-floret technique (0.76 for mass spray and 0.72 for colonized seed).

Based on the above findings, we now have a 2,000-sq ft greenhouse dedicated entirely to screening for Fusarium head blight resistance. Hills (5 seed per hill, hills 15 cm apart) are planted in soil-beds, misting is provided beginning at anthesis, and inoculum is provided by both spraying and spreading colonized seed. We can evaluate 4,500 hills in each greenhouse cycle (Autumn cycle is September-December, and spring cycle is January-April). (J.C. Rudd, S.S.A. Rizvi, Y. Jin)

Wheat anther culture. In a joint project with Dr. Chen, we are evaluating anther culture as a tool to select for tan spot resistance. Results indicate that the addition of toxin produced by the tan spot fungus to the anther culture medium can be used to select for resistance to the toxin in segregating populations. This research has allowed us to use anther culture to transfer toxin resistance to different genetic backgrounds much more rapidly than with conventional breeding. We have now confirmed that plants resistant to this toxin also have a higher level of resistance to the tan spot disease. Approximately 2,000 double haploid lines were evaluated in 1995 field trials. (R. Yu, S. Zhu, C.H. Chen, J.C. Rudd)

Publications.

Farber BG and Rudd JC. 1995. Mechanical mass selection for test weight in hard red spring wheat. In: Proc 20th Hard Red Winter Wheat Workers Conference, 24-27 January, 1995, Oklahoma City, Oklahoma.

Rizvi SSA, Fisher L, Rudd J, and Gallenberg D. 1995. Resistance of spring wheat cultivars/lines to head blight (scab) in greenhouse tests. North Central Division American Phytopathological Society. 20-22 June, 1995. Brookings, South Dakota.

Aldana F. 1995. High temperature tolerance of eight spring wheat lines of diverse origin. Ph.D. dissertation. South Dakota State Univ, Brookings.

Ruden B. 1995. Measurement of osmoregulation of the coleoptiles of spring wheat as a screening technique for drought tolerance potential. M.S. thesis. South Dakota State Univ, Brookings.

Yu R. 1995. Rapid selection for tan spot resistance through anther culture of spring wheat F1 Hybrids. Ph.D. dissertation. South Dakota State Univ, Brookings.