GrainGenes

St. Matthews, South Carolina, USA.

Benjamin E. Edge and Phil Shields.

The 1994-95 season. The season got off to a good start in the northern part of our testing area, with wheat planting going smoothly in those areas. Our home nursery was delayed by a late cotton harvest followed by excessive rain at planting. December and January were very wet, so root development did not occur as it should have during the winter. We experienced a severe drought that started at the end of February and lasted until the first of June. As a result, we had very little powdery mildew pressure and lower than normal yields. Leaf rust was more severe than usual, however. Cereal leaf beetle damage was severe in some areas. We had a location at Darlington, SC, that had close to 100 % infestation, with many leaves completely stripped.

We moved our secondary nursery from Statesboro, GA, to Rowland, NC, in the hopes for more consistent yield and disease data. This turned out to be a good year to do it, because the yield location at Statesboro was a total loss. However, Rowland had good yields despite the drought and also had high levels of leaf rust infection and Hessian fly infestation. Some varieties that had been resistant to Hessian fly in this area are becoming infested, as the mix of biotypes changes (Table 2). We saw some stem rust at this location, and enough European corn borer damage occurred to cause significant yield loss. We feel that this move will help us screen for more diseases and insect pests, as well as help to identify high-yielding, medium-maturing varieties.

As we began harvest, the rain began to fall. Severe sprouting of grain occured at some locations. The wheat that was harvested early had excellent test weights, but as we moved north, the weights were somewhat lower. Still, yields were better than we might have expected; our elite yield test averaged 5.0 t/ha. Northern locations yielded much better than those to the south, averaging 5.8 t/ha and 3.9 t/ha respectively.

Table 2. Hessian fly infestation of wheat cultivars grown at Rowland, NC, in 1994-95.

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% Stem % Stem

Variety Hessian Fly/Stem Infestation Variety Hessian Fly/Stem Infestation

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Pioneer 2691 0.00 0.0 Pioneer 2628 0.50 30.0

Pioneer 2684 0.03 2.5 Pioneer 2548 0.65 32.5

Pioneer 2566 0.18 5.0 Coker 9803 0.88 45.0

Clemson 201 0.05 5.0 Coker 9904 1.28 47.5

Georgia Andy 0.15 7.5 Agripro Hickory 0.78 50.0

Coker 9543 0.13 7.5 Coker 9134 1.53 57.5

Coker 9835 0.45 22.5 VPI Jackson 1.20 57.5

Agripro Savannah 0.30 25.0 Georgia Gore 1.58 65.0

Pioneer 2643 0.38 25.0 Pioneer 2552 1.63 75.0

Pioneer 2580 0.50 25.0

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Mean of 40 dissected culms/cultivar as determined by J.W. Chapin and J.S. Thomas, Edisto REC, Blackville, SC.

We continued testing in the mid-south, with Fred Collins growing some test plots in Arkansas for us to supplement the ones our agronomists plant. One location in Arkansas was hit hard by take-all, but some experimental lines showed good levels of resistance. Head scab and barley yellow dwarf virus again were problems in the mid-south. Hessian fly also was easy to find, because early planting dates were conducive to a buildup in the population.

Because of the drought and disease pressure, the number of selections going into F3 headrows fell from 52,000 in 1994-95 to 46,000 in 1995-96.

New releases. We released one new variety in 1995. `Pioneer 2691', formerly XW631, is a very early-maturing variety with high yield potential for the East Coast and Deep South. 2691 heads 3-5 days earlier than Pioneer 2684, and its average yield was 2,684 during the 4-year period from 1992-95. Pioneer 2691 is awned, with good leaf rust and powdery mildew resistance, good lodging resistance, and tolerance to the predominant biotypes of Hessian fly in the southeast.

Miscellaneous items. Partners of Pioneer (or POP), our new marketing system for wheat sales in the south, completed its first year of sales to farmers in 1994-95. Pioneer sells parent seed of wheat varieties to several partner seed producers, who then produce commercial seed, sell it to farmers, and pay a royalty to Pioneer based on the number of units sold.

We completed construction of our new research office facility in St. Matthews in February of 1995. This facility provides additional equipment storage, lab space, and cold room capacity, and the convenience of being close to our greenhouses.

Parndorf, Austria.

Guenther Reichenberger.

Pioneer wheat varieties were tested at locations in northwestern and northeastern Austria at a total of 12 locations, including official testing sites. Trials were early-generation, single-rep screenings, and advanced replicated yield trials. Our latest A3 variety, Victo, performed very well across all environments. This has been a surprise to many officials, because short varieties usually are not expected to yield well in the dry region of eastern Austria. Furthermore, Victo exhibited good yield stability over 3 years of testing. Victo out-yielded check varieties by 5-15 % or even more at some locations.

After 3 years of intensive testing, we found Victo to be very resistant to powdery mildew and leaf rust, whereas susceptibility to stripe rust is above average. Considering that Austrian commercial varieties are much taller than Victo (+ 20-30 cm), one might expect effects of shading on yield performance in small-plot trials. In large plots (Pioneer strip trials with 1,000 square meters per plot), Victo proved to be an extraordinary yielding variety with very good agronomic properties, such as lodging resistance and disease resistance.

Lodging was severe at a number of locations in northwestern Austria after a series of heavy rains and hail during the summer. Victo, like a large number of other Pioneer cultivars, showed above-average standing ability and good harvestability. Earliness is another factor that adds value to our varieties.

The Austrian wheat market has stabilized after some years of decline. In contrast to other crops that had been introduced about 10 years ago to reduce cereal overproduction (and subsidized heavily by the government), wheat is a crop that is grown traditionally in Austria. The market includes feed wheat and very high quality bread wheat to supply local millers and bakers. The breadmaking tradition is old in Austria, and the number of different types of bread ranges from white rolls to dark breads.

Frouville, France.

G. Dorlencourt, Steven Bentley, Robert Marchand, Elie Guillard, and Quitterie Vanderpol.

The 1994-95 season. The absence of winter was probably the most important fact of this testing season. Wheat emerged and grew very rapidly in November, although temperatures were much higher than normal.

Temperatures were 6.0-C above average in November, 1.0-C above average in December, 1.0-C above average in January, 3.0-C above average in February, and 2.4-C above average in March.

These temperatures caused early regrowth of the very early and facultative wheats. In April and early May, the temperatures went up to 21-C on one day and dropped to freezing level a day later. This weather pattern was accompanied by very low solar radiation. Therefore, the earliest varieties at the critical meiosis stage had some bad sterility. In addition, aphids carrying BYDV remained on the wheat plants all winter long and caused additional heading problems, mostly on early planted crops that were not pesticide protected. In our disease nursery, we recorded good data on stripe rust, after artificial inoculation. We also had a good natural infection of Septoria tritici for the second year in a row, which is unusual.

Harvest conditions were very favorable, resulting in good quality. The average yield was 5 to 20 % lower than that in past years, depending on the region, planting date, and type of varieties grown.

Varietal development. Our new variety, `Victo', and other new, very early varieties were penalized by the weather conditions when planted before 20 October. In Europe (Italy and Austria), Victo performed very well, which confirms the past years' testing results.

We have entered three new varieties (2235, 2271, and 2262) in official registration trials in the south of France. `2235' has proved to be a good biscuit quality wheat, `2271' is an early dwarf with good breadmaking quality, and `2262' has average quality, but outstanding yield potential. These varieties are all resistant to powdery mildew and leaf rust. `2221', a late, good baking-quality variety, entered registration in the North.

Miscellaneous items. We started crosses at Frouville in 1990, so the program is becoming mature. Consequently, the number of plots tested over our four locations in the north and four in the south greatly increased this year.

We continued supporting and supplying seed for screening and testing in the U.K., Germany, Italy, northern Spain, Austria, and central Europe.

Our new central laboratory, located at Buxtehude, is performing quality tests and analysis for our European locations. Our work in the greenhouse continues to include crosses for European projects, single seed descent, hybrid wheat development, and other special projects.

Sissa (near Parma), Italy.

Mauro Tanzi.

The 1994-95 growing season. September and October rainfall delayed planting in most northern Italian regions; timely planting took place in the southern regions. The mild winter helped promote fast crop growth, particularly of the facultative or spring type varieties. The latter were more damaged by the frost, which occurred at the end of February and beginning of March in the north. Drought conditions in March and April reduced plant growth and tillering. During the late grain filling period, rain had a negative effect on grain production and quality. Pathogens of the plant head, such as Septoria nodorum and Fusarium spp., were widespread in bread wheat fields. Again, in the northern regions, a wider infection of soilborne wheat mosaic and wheat spindle streak mosaic was registered, but with a low impact on yield. In the central and southern regions, where mostly durum wheat is grown, drought and high temperatures affected plant growth, flower fertility, and production. Only in a few areas with June rainfall was the yield level increased.

Varietal development. We planted six yield trial locations throughout northern and central Italy, testing bread and durum wheat lines from the French, Spanish, and US Pioneer breeding programs. We have started a strip-trial evaluation of the bread type variety Victo (two fields). This variety outyielded the checks by more than 0.7 mt/ha (11 %). Three durum wheat varieties had successfully completed the registration process and were included into the national varieties recommendation list. We are increasing seed of the following three varieties: Preco, Bracco, and Colorado. The main features of the registered durums are:

- good grain protein content

- gluten quality

- semolina color

Evaluation of the different durums for grain quality has been accomplished with the cooperation of some of the main pasta manufacturers such as Agnesi and Barilla, and the Pioneer station labs of Sevilla (Spain) and Buxtehude (Germany). Bread wheat lines also were evaluated in private mill labs. Five new bread wheat lines and one new durum were entered into first-year registration trials. Multiplication of the variety Victo foundation seed was planned on a small hectarage base.