UTAH

Utah State University

Plant Science Department, Logan, UT 84321, USA.

Spring wheat.

R.S. Albrechtsen.

Production, diseases, and insects. Utah's 1994 harvested spring wheat acreage was down slightly from that of the previous year. A warm, dry summer also resulted in a three-bushel lower average yield and a lower total production than in 1993.

Spring wheat diseases were generally minimal. Losses from the cereal leaf beetle and the Russian wheat aphid were spotty.

Breeding program. We continue to reduce the effort in our spring wheat breeding program. We are testing materials left in the system and are identifying other adapted materials from the Western Regional Spring Wheat Nursery.

Cultivars. Rick (HRS) continues to perform well under both irrigated and nonirrigated conditions.

A new hard red spring cultivar, (`Sylvan', UT002464) developed in our program was recently released jointly by the Utah and Colorado Agricultural Experiment Stations. It has performed particularly well under irrigation in southwestern Colorado.

Winter wheat.

D.J. Hole.

Production, diseases, and insects. Harvested acreage of Utah's 1994 winter wheat crop was 150,000 acres, down slightly from 1993. Average yields statewide were 40 bu/acre, and total production was about 6 million bu. The warm spring and unusually hot dry summer combined to accelerate the wheat harvest about 7 days.

Dwarf smut levels were low throughout the state mainly because of continued stability of current resistant cultivars. The cereal leaf beetle continues to move north through the state, although losses were minimal this year. Incidence of Russian wheat aphid was also lower this year.

We began a study, in collaboration with the Ag. Systems Department, to examine cultivars and breeding lines for organic hard wheat production. More of the producers in the semi-arid northwestern region of the state are beginning to produce wheat organically. With no supplemental nitrogen applications, quality is a concern for these producers. We are examining breeding lines, cultivars, and the impact of addition of composted dairy waste on production.

New cultivars. Two advanced lines were placed into breeder seed production in the fall of 1994. UT1650-150 is designed as a replacement for Promontory in the extremely dry areas of Utah such as Cedar Valley. It is a hard red winter dryland type. UT1944-157 is a hard white winter dryland wheat with good breadmaking and Asian noodle qualities. The Utah Agricultural Experiment Station has not made any decision on release of these two lines.


VIRGINIA

Virginia Polytechnic Institute and State University

Departments of Crop and Soil Environmental Sciences and Plant Pathology, Physiology and Weed Science, Blacksburg, VA 99163, USA.

Virginia wheat production in 1994.

C.A. Griffey and D.E. Brann.

Growing conditions. The 1993-94 growing season began with a dry fall, followed by normal to above average precipitation from December to March and ended with a considerable dry period from April through June. Temperatures generally were normal to above average throughout most of the fall. From January 15 to 23, minimum temperatures throughout most of the wheat growing areas were below 20 F, with temperatures below 0 F on several days. Even with this period of severe temperatures, winterkill was not significant.

1994 winter wheat production. According to the Virginia Agricultural Statistics Service, 250,000 acres (101,250 ha) of soft red winter wheat were harvested in Virginia in 1994. An average yield of 56 bu/acre (3,760 kg/ha) was obtained in 1994 and approached the state record of 57 bu/acre (3,830 kg/ha) set in 1992. Total wheat production in 1994 was 14 million bushels (381,360 metric tons).

1994 Virginia Wheat Yield Contest. Thirty-five wheat producers representing 14 counties participated in the 1994 Virginia Wheat Yield Contest. Mr. David Hula of Charles City county had the highest yielding wheat at 144 bu/acre (9,675 kg/ha) over a minimum area of 3 acres (1.2 ha). Nineteen of the producers had grain yields of 100 bu/acre (6,720 kg/ha) or higher.

State cultivar tests. Seven public and 18 private wheat cultivars were evaluated at seven locations in Virginia in 1994. The cultivars Jackson, Coker 9835, and Pioneer 2643 were the highest yielding, with average yields of 84 bu/acre (5,640 kg/ha). Other cultivars with average yields ranging from 81 to 83 bu/acre (5,440-FONT SIZE=2 FACE="Times New Roman"5,575 kg/ha) and equivalent to the top-yielding lines were FFR 555W, GA-Gore, Pioneer 2580, and Baytan-treated Saluda, Wakefield, FFR 555W, and Coker 9543. Test weights ranged from 54.8 lb/bu (705 kg/m3) to 60.3 lb/bu (776 kg/m3) and averaged 58.5 lb/bu (753 kg/m3) over cultivars.

Treatment thresholds for leaf and glume blotch in wheat.

E.L. Stromberg.

After four seasons of field research, a treatment threshold has been developed and recommended for use in Virginia for application of foliarly applied fungicides to control leaf and glume blotch caused by Stagonospora nodorum (Berk.) Castellani & E.G. Germano [syn. Septoria nodorum (Berk.) Berk. in Berk. & Broome]. The treatment threshold is based on the presence of lesions on indicator leaves that change with the growth stage of the wheat plant. The protocol for use of the treatment threshold is as follows:

Scout fields weekly from Zadoks' growth stage 31 through 73 (Feekes' 6 through 11). Randomly select 10 locations within the wheat field. At each randomly selected location, examine and record the number of indicator leaves out of 10 main tillers with one or more leaf and glume blotch lesions. After examining and recording 100 indicator leaves, if 25 % have one or more lesions, a fungicide application is indicated (See Pest Management Guide for Field Crops, Virginia Cooperative Extension Publication 456-016 for specific fungicide recommendation).

Indicator leaves for leaf and glume blotch thresholds.

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Growth stage

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Zadoks' Feekes' Indicator leaves

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31-37 6-8 Flag-4 and Flag-5

38-45 8-10 Flag-3

46-FONT SIZE=2 FACE="Times New Roman"59 10-10.51 Flag-2

60-73 10.52-11 Flag-1

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Data from research plots have shown that when treatment thresholds are reached as late as Zadoks' growth stages 69-73 and fungicide applications are made, the yield responses have been as great or greater than with a growth stage 37 application or even applications made every 14 days from growth stage 32 through 69. It is estimated that only 25 % of fields sprayed at growth stage 37 for leaf and glume blotch actually benefit economically from such an application. Use of treatment thresholds to indicate need for fungicide application is an economically and environmentally sound practice for Virginia wheat growers.

Publications.

Alley MM, Scharf P, Brann DE, Baethgen WE, and Hammons JL. 1994. Nitrogen management for winter wheat: Principles and recommendations. Virginia Coop Ext Pub 424-026. 6 pp.

Brann DE, Griffey CA, Price AM, Rucker-Bender E, Behl H, Stromberg EL, and Keister J. 1994. Small grains in 1994. Virginia Coop Ext Pub 424-001. 12 pp.

Chung YS and Griffey CA. 1995. Powdery mildew resistance in winter wheat. I. Gene number and mode of inheritance. Crop Sci 35(2):(In press).

Chung YS and Griffey CA. 1995. Powdery mildew resistance in winter wheat. II. Identity of resistance genes. Crop Sci 35(2):(In press).

Das MK and Griffey CA. 1995. Gene action for adult-plant resistance to powdery mildew in wheat. Genome (In press).

Stromberg EL and Komm DA. 1994. Evaluation of foliar fungicides for the control of disease in Coker 916 soft red winter wheat, 1993. Fungicide and Nematicide Tests 49:232-233.

Stromberg EL and Komm DA. 1994. Evaluation of foliar fungicides for the control of disease in Wakefield soft red winter wheat, 1993. Fungicide and Nematicide Tests 49:234-235.

Stromberg EL and Sagaral RG. 1994. Evaluation of seed treatment fungicides and an insecticide for disease control in Wakefield soft red winter wheat, 1993. Fungicide and Nematicide Tests 49:319-320.