PIONEER HI-BRED INTERNATIONAL, INC.

Worldwide Wheat Research, Windfall, IN USA.

Varietal development.

Gregory C. Marshall.

Pioneer released seven new varieties in the U.S. and Europe in 1998:

25W60 is an SWWW with high yield potential, excellent test weight and resistance to powdery mildew resistance, and strong resistance to the soilborne viruses. 25W60 was granted full registration in Canada.

26R46 and 26R61 are two high-yield potential SRWW varieties with good test weight and disease resistance for the southern U.S.

Kenzo, Destino, and Testo are three SRWW varieties that passed second-year trials for official registration in france. Kenzo is a superior baking quality wheat with good disease and lodging resistance. Destino and testo are both regular bread quality with good disease resistance.

Derwent is the first Pioneer® brand wheat variety to pass U.K. registration for the national list. Derwent is a feed quality, SRWW with good yield potential and strong disease resistance.

Personnel changes.

Ian Edwards resigned his position as field crops director in October of 1998, after nearly 21 years at Pioneer. Ian is now research director with Biowest Australia Pty. Ltd. in Perth, Western Australia.

Windfall, IN, USA.

Gregory C. Marshall, William J. Laskar, Kyle J. Lively, Robert L. Clarkson, Gary P. Off, and
Samuel A. Tragesser.

The 1997-98 season. The wheat planting season in the autumn of 1997 presented significant challenges. Seedbed condition at most of our northern testing sites was adversely affected by wet soil conditions at planting. Meanwhile, many locations in the central and southern regions of our testing area had very little soil moisture at planting. As a result, stand establishment was delayed and erratic, until rains over the entire region in late October effectively ended the planting season but provided moisture needed to complete emergence.

The mild winter encouraged continued growth, and by late winter, the crop appeared to have excellent yield potential. Unfortunately, a sudden drop in temperatures in early March caused varying amounts of freeze damage to the crop starting in southern Indiana and Illinois and continuing south into Kentucky, Tennessee, and Arkansas.

The remainder of the spring season was mild and relatively wet, which favored good recovery of the freeze damaged plants, but allowed soilborne virus disease symptoms to develop and foliar leaf disease infection to begin. Disease pressure continued to increase as warm temperatures quickly pushed the crop to maturity. A total of nearly 35,000 individual disease and agronomic notes were taken prior to harvest, providing evidence that the wheat crop was being stressed in many ways.

Ample levels of leaf blight, severe leaf rust, moderate head scab, and significant lodging were all present in our selection nurseries, making selection quite challenging. Harvest began 2 weeks earlier than normal. Yield levels were variable. Our two southernmost yield test locations averaged only 50 bu/acre, because of excessive disease pressure and lodging brought on by the wet conditions and spring storms. Yield at our remaining locations was very good, though somewhat disappointing considering the crop's potential earlier in the season.

Equipment. We purchased a Hege 160 plot harvester equipped with a HarvestMaster GrainGage harvest system and HarvestMaster Pro2000 handheld computer. The GrainGage system collects field weight, test weight, and moisture data. We have been very satisfied with the accuracy of the field weight and moisture data and have worked closely with HarvestMaster to resolve some concerns about test weight accuracy. The new harvester, combined with the GrainGage harvest system, allows us to harvest plots 10 feet in length and process the data in approximately 20 seconds per plot.

Varietal development. Pioneer®-brand variety 25W60, an awned, medium-maturing SWWW, has been released and will be available for sales in the autumn of 1999. The variety is adapted to all the white wheat growing areas of the eastern U.S. and Ontario, Canada, where it has been granted registration. 25W60 has outstanding yield potential and has yielded 5.0 bu/acre more than 2737W over the last 5 years of testing. 25W60 exhibits superior test weight, excellent powdery mildew resistance, and strong resistance to both WSBMV and WSSMV.

Personnel changes. Samuel Tragesser was hired in December, 1998, as a research associate. Sam received his B.S. degree in agronomy from Purdue University in December, 1997. He will be involved with most areas of the wheat breeding effort with emphasis on greenhouse management, seed processing, and data management.

St. Matthews, South Carolina, USA.

Benjamin E. Edge, David E. Moon, and Robert E. Williamson.

The 1997-98 season. Wheat suffered from a wet autumn and winter in the southeastern U.S. Temperatures were generally mild, but a freeze in march caused damage to early maturing varieties. After March, weather was extremely dry, so wheat did not have adequate moisture during heading and grain fill. Test weights were low as a result, even though rainfall was limited at harvest. Leaf rust was severe in our breeding nursery and in several testing locations. Leaf blights, including Septoria spp. and bacterial blights, were prevalent over much of the area. Cereal leaf beetle continues to be a problem in the southeast and is especially severe when spring is long and cool, as it was this year.

Varietal development. Our secondary nursery in North Carolina was lost because of poor stands from excessive rainfall, and yield data from several other locations were questionable because of poor stands and uneven uniformity of plots. Bird and deer feeding on awnless varieties ruined the results from one of our yield test locations. Our home nursery was planted much later than usual, because of wet soil conditions, but managed to give us near average yields.

We gave commercial numbers to two lines in 1998. Xw662 was promoted to 26R46, and xw663 was promoted to 26R61. 26R46 is adapted to much of the area where 2580 performs well. 26R61 has good disease resistance and Hessian fly resistance. We entered two new experimentals, XW672 and XW674, into the uniform southern nursery for 1998-99.

Frouville, France.

Guy Dorlencourt, Steven Bentley, Quitterie Guerin, Elie Guillard, and Ghislaine Espinasse.

The 1997­98 growing season. The growing conditions were very favorable to wheat resulting in the best yield ever (7.8 mt/ha). Most of the wheat was harvested in good condition. Protein level was generally low, but the bread quality was quite good. In our nursery, we had a very bad infection of stripe rust, although leaf rust was lower than normal. A new stripe rust coming from U.K. was naturally present in experiments in northern France and should spread in future years. Finally, we had a good season for screening on stripe rust, leaf rust, Septoria tritici, and lodging.

Varietal development. Three varieties originating from the first crosses made when the program was initiated in France and were registered on the official list. Kenzo is a superior bread-making wheat and shows good resistance to the main diseases. Kenzo is short with very stiff straw and medium-late; yield was registered in the northern area at 102.2 % of the official checks. Destino has good bread-making quality. The yield was registered at 104.9 % of the checks, has good overall resistance to the main diseases, and is medium-early. Yield of Testo was registered in the south at 106.7 % of the checks, but it is performing well also in the Paris Basin, southern Germany, and Austria. Testo is early, has good bread-making quality, and received a bonus at registration for its overall resistance to the main diseases.

Breeding. Even if yield remains a priority, we are focusing more and more on end-users' requirements by screening on-site with SDS Zeleny, mixograph, glutomatic, and NIRS assays for proteins. Our central laboratory also is scoring hardness, conventional SDS, falling number, and HMW-glutenin content.

The size of our disease nursery is still increasing with duplication of lines from F4 to registration on which we artificially inoculate stripe rust, leaf rust, and S. nodorum. Since the beginning, we also have considered screening for S. tritici resistance very important. We had the opportunity to screen heavily for this trait, and results are quite encouraging.

Personnel changes. Quitterie Guerin-Vanderpol resigned at the end of September, 1998, to take a teaching position. A search for a replacement is underway.

Blisworth, Northampton, U.K.

Paul Wilson, Graham Urquhart, and Simon Short.

1997-98 growing season. Good seedbeds and good establishment occurred at all yield trial and nursery locations. Mild and wet winter weather allowed very good plant development at all locations during the spring. Rain in June caused high disease (stripe rust, leaf rust, and S. tritici) and lodging pressure throughout the remainder of the season. Leaf rust developed much earlier in the year than normal, because of the very mild conditions in January and February. Despite the lack of really high temperatures during the remainder of the growing period, leaf rust infection increased to cause very severe symptoms on susceptible lines in July. Conditions also were ideal for the development of stripe rust allowing for excellent screening for resistance to this pathogen.

Harvest conditions were fair, although not particularly hot. Some rain caused interruptions towards the latter part of August, but all yield test sites and the nursery were harvested before serious damage was caused. Yield of trial plots was the highest in a number of years, with maximum yields recorded between 11 and 12 t/ha (before field correction).

Crossing program. For the first time, the crossing program for the U.K. was carried out at the U.K. station. Prior to this, the crosses were made in France and the F2s shipped to the U.K. for planting in the field. The crossing program was run in the U.K. breeding barn under a polythene tunnel designed to maintain the correct lighting and heat regime for the growth of the parent plants. Crosses were made between January and February, which allowed the F1 seed to be vernalized and replanted in polytunnels for generation of F2 seed ready for planting in the field in October the same year. Approximately 400 crosses were made. Seed return from the F1s was sufficient to plant a single row of F1s in the polytunnel for F2 production.

Varietal development. Derwent became the first Pioneer® brand wheat variety to pass U.K. national list registration. Derwent is a winter-feed variety with good yield potential and all-round disease resistance. Yield performance in official trials was 102 % of checks. Another winter-feed variety was advanced to second-year registration trials, and two new varieties were entered into first-year trials in September, 1998.

Personnel changes. Graham Urquhart resigned his position as research associate at the Blisworth, U.K. program in January, 1999.