GrainGenes

ITEMS FROM THE UNITED STATES

VIRGINIA

VIRGINIA POLYTECHNIC INSTITUTE AND STATE UNIVERSITY

Department of Crop and Soil Environmental Sciences 1 and Department of Plant Pathology, Physiology and Weed Science 2; Blacksburg, VA 240610404, USA.

W.L. Rohrer, J.A. Wilson, C.A. Griffey, D. Nabati, J. Chen, T.H. Pridgen, E.G. Rucker, and D.E. Brann.

2002 Wheat Production in the Commonwealth of Virginia. [p. 223-225]

W.L. Rohrer, C.A. Griffey, and D.E. Brann.

Growing conditions. The 2001-02 growing season was extremely dry with temperatures fluctuating but generally mild. Very little precipitation fell during the winter months. The dry and mild conditions were briefly interrupted by flash flooding in some areas (particularly southwest Virginia) and a spring freeze, both occurring in March. A later spring freeze occurred in May causing additional damage to wheat that was in the heading to post anthesis stages. As in recent years, both the Blacksburg and Warsaw areas remained extremely dry throughout most of the spring and summer. Because of the dry conditions, disease prevalence and severity was low in most areas. Crop lodging also was generally low because of lack of heavy precipitation late in the growing season. Rains during the harvest season delayed combining and resulted in reduced test weights in a portion of the crop.

Disease incidence and severity. Leaf rust, powdery mildew, and BYDV were the most prevalent diseases of wheat in Virginia in 2002. Powdery mildew was prevalent in most wheat-production areas of the state and was most severe in the Coastal Plain and Eastern Shore regions. Although leaf rust was observed in several regions of the state, it generally developed late in the season and disease severity was low. However, significant leaf rust infection of wheat was observed on the Eastern Shore of Virginia. The incidence of FHB generally was low, although isolated foci were observed. Stripe rust was prevalent in Virginia Tech yield nurseries near Blacksburg in the western part of the Commonwealth.

Production. According to Virginia Agricultural Statistics Service, Virginia producers harvested 185,000 acres (74,925 ha) of winter wheat for grain in 2002, which was up from the 170,000 (68,850 ha) acres harvested in 2001. Grain yields across the state averaged 63 bu/acre (4,233 kg/ha), which was 4 bu/acre (269 kg/ha) lower than the state yield-record set in 1997 and 6 bu/acre (403 kg/ha) higher than in 2001. Total grain production for the Commonwealth in 2002 was 11.7 million bushels (318,367 metric tons).

Virginia wheat yield contests. Participation in the conventional-till and no-till wheat yield contests was up in 2002. In the 2002 Virginia Conventional-Till Wheat Yield Contest, Robbie Newcomb of Hanover County took first place with a grain yield of 112 bu/acre (7,525 kg/ha) over a minimum area of 3 acres (1.2 ha). Battle Park Farm, located in Culpeper County, came in second with a yield of 111 bu/acre (7447 kg/ha) followed closely by Richard Sanford of Westmorland County with 110 bu/acre (7,394 kg/ha). Clay Newcomb of Hanover County led a group of four participants in the Conventional-Till Rookie Class with a yield of 106 bu/acre (7,090 kg/ha). Jimmy Newcomb of Hanover County, F.F. Chandler, Jr. of Westmoreland County, and Sam B. Drewery, Jr. of Southampton County captured 2nd, 3rd, and 4th places, respectively. In the 2002 Virginia No-Till Wheat Yield Contest, Todd Price of Prince George County took first place with a grain yield of 99 bu/acre (6,629 kg/ha). Finishing in 2nd and 3rd places were Alvis Farms of Goochland County (97 bu/acre (6,541 kg/ha)) and William Bendle, Jr. of Henrico County (96 bu/ac (6,439 kg/ha)), respectively. In the No-Till Rookie Class, Tony Knasnicka of Prince George county captured first place with a grain yield of 93 bu/acre (6,242 kg/ha) and was followed by Joseph Reamy of Richmond County (2nd place) and Craig Brann of Northumberland County (3rd place). Congratulations go out to all of the participants in this year's yield contests.

State cultivar tests. A total of 65 entries were evaluated at 6 locations across Virginia in 2002. Included in the tests were 37 experimental lines (including one white-seeded line) and 28 released cultivars. Average grain yields ranged from 59 to 90 bu/acre (3,964-6,047 kg/ha) with an overall test average of 76 bu/acre (5,106 kg/ha). Wheat genotypes with yields significantly above the test average included Tribute, McCormick, Sisson, SS 550, SS520, SS 560, USG 3209, USG 3650, Pioneer 2580, and 17 experimental lines (16 from the Virginia Tech program, including one white-seeded entry). Yields among genotypes in this group ranged from 80 to 90 bu/acre (5,375-6,047 kg/ha). Tests conducted in the Coastal Plain Region had a yield average of 83 bu/acre (5,577 kg/ha), whereas tests conducted in the Piedmont and Blue Ridge Region had a yield average of 71 bu/acre (4,770 kg/ha). Test weights of wheat lines (based on five locations across the state) ranged from 56.8 lb/bu (731 kg/m3) to 60.7 lb/bu (781 kg/m3) with a test average of 58.6 lb/bu (754 kg/m3). Of the 19 entries with test weights significantly higher than the test average, nine were experimental lines (six from Virginia) and 10 were released cultivars. Six entries (four Virginia experimental lines and two released cultivars) had both grain yields and test weights that were significantly higher than the test average.

Release of McCormick. Formerly designated VA98W-591, McCormick was released by the Virginia Agricultural Experiment Station in May 2002. The name McCormick was selected in tribute to Robert Hall McCormick of Walnut Grove in Rockbridge County, Virginia, and his sons Cyrus Hall McCormick and Leander James McCormick. Their invention and perfection of the mechanical reaper initiated the era of modern agriculture and wrought one of the greatest advancements in agricultural history, thus enabling the world's production of food to keep pace with the vast increase of population.

McCormick is a broadly adapted, mid-season, high-yielding, short-stature, awnleted, SRWW with good straw strength. McCormick was derived from the cross 'VA92-51-39/AL870365'. The cross was made in spring 1992, and the F1 generation was grown in the field as a single 4-ft headrow in 1993 to produce F2 seed. The population was advanced from the F2 to F4 generation using a modified bulk-breeding method. McCormick was selected as an F5 headrow in 1997.

Head emergence of McCormick is 2 days later than AGS 2000 and 1 to 2 days earlier than Roane. Average plant height of McCormick (31 inches, 79 cm) is similar to that of Coker 9835 and 2 to 3 inches (5 to 8 cm) shorter than AGS 2000. Straw strength of McCormick is good and is better than that of Coker 9663. Based on data from six test sites in the 2001 Uniform Eastern SRWW Nurseries, winter survival of McCormick is good and similar to that of Caldwell. Milling and baking quality of McCormick is good and superior to that of Roane.

Reaction of McCormick to disease and insect pests has been evaluated over a broad area. McCormick is resistant to powdery mildew. In seedling tests of entries in the 2001 Uniform Eastern and Southern SRWW Nurseries conducted by USDA-ARS Plant Science Research Unit in Raleigh, NC, McCormick expressed resistance to 24 of 30 isolates. McCormick possesses the Pm17 gene from Amigo in addition to other unidentified genes. Similar data from the Cereal Disease Laboratory in St. Paul, MN, indicates that McCormick possess gene Lr24 conferring resistance to leaf rust and genes Sr6, Sr17, and Sr24 conferring resistance to stem rust. McCormick is resistant to stripe rust and WSBMV. McCormic is moderately resistant to leaf blotch, glume blotch, FHB, BYDV, and WSSMV.

In Virginia, grain yields of McCormick have been similar to or exceeded those of the best check cultivars and over the past 2 years (2000-01) have averaged 83 bu/acre (5,577 kg/ha) versus a mean yield over all genotypes of 76 bu/acre (5,106 kg/ha). Grain of McCormick is high in test weight (mean of 60.5 lb/bu; 779 kg/cm^3^), which is similar to that of Roane (60.2 lb/bu) and 3 lb/bu higher than that of Coker 9835. McCormick was evaluated for 2 years in the USDA-ARS Uniform Southern SRWW Nursery and ranked first among 43 entries for grain yield (77 bu/acre; 5,174 kg/ha) and sixth in test weight (59.1 lb/bu; 761 kg/cm^3^) in 2001. In 2002, it ranked third among 40 entries for grain yield (63 bu/ac; 4233 kg/ha) and fifth in test weight (58.3 lb/bu; 750 kg/cm^3^). McCormick also was evaluated for two years in the Uniform Eastern SRWW Nursery, and ranked first among 44 entries for grain yield (79 bu/acre; 5,308 kg/ha) and ranked fifth in test weight (60.1 lb/bu; 773 kg/cm^3^) in 2001. In 2002, it ranked eighth among 44 entries for grain yield (71 bu/acre; 4,770 kg/ha) and third in test weight (59.4 bu/acre; 764 kg/cm^3^).

Authorized seed classes of McCormick are Breeder, Foundation, and Certified. McCormick is protected under the amended U.S. Plant Variety Protection Act of 1994 (Application pending). The Department of Crop and Soil Environmental Sciences and the Virginia Agricultural Experiment Station, Blacksburg, Virginia, will maintain Breeder seed. Requests for participation in production of McCormick and availability of Foundation seed should be directed to Bruce Beahm (804-472-3500), Manager, Foundation Seed Farm, Mt. Holly, VA.

Release of Tribute. Formerly designated VA98W-593, Tribute was released on an exclusive basis by the Virginia Agricultural Experiment Station in May 2002. Tribute is a broadly adapted, mid-season, high-yielding, short-stature, awnleted, SRWW with good straw strength. Tribute was derived from the cross 'VA92-51-39/AL870365'. The cross was made in spring1992, and the F1 generation was grown in the field as a single 4-ft headrow in 1993 to produce F2 seed. The population was advanced from the F2 to F4 generation using a modified bulk-breeding method. Tribute was selected as an F5 headrow in 1997.

Head emergence is 2 to 3 days later than AGS 2000 and 2 days earlier than Roane. The average plant height of Tribute (32 inches, 81 cm) is 1 to 2 inches (3 to 5 cm) taller than Coker 9835 and 2 inches (5 cm) shorter than AGS 2000. Straw strength of Tribute is good and better than that of Coker 9663. Based on data from seven test sites in the 2000 and 2001 Uniform Eastern SRWW Nurseries, winter-survival of Tribute is good and similar to that of Caldwell. Milling and baking quality of Tribute is slightly better than that of Roane. Tribute has the 5+10 glutenin-protein subunit and strong gluten strength, thus making it potentially suitable for cracker production.

Reaction of Tribute to disease and insect pests has been evaluated over a broad area. Tribute is resistant to powdery mildew. Based on seedling tests of entries in the 2000 Uniform Eastern and Southern SRWW Nurseries conducted by USDA-ARS Plant Science Research Unit in Raleigh, NC, Tribute possesses the Pm17 gene from Amigo in addition to other unidentified genes. Similar data from the Cereal Disease Laboratory in St. Paul, MN, indicates that Tribute possesses genes Lr9 and Lr24 conferring resistance to leaf rust and gene Sr24 conferring resistance to stem rust. Tribute is moderately resistant to stripe rust, leaf blotch, glume blotch, FHB, BYDV, and WSSMV; it is susceptible to WSBMV.

In Virginia, grain yields of Tribute have been similar or exceeded those of the best check cultivars and have averaged 83 bu/acre (5,577 kg/ha) versus a mean yield over all genotypes of 76 bu/acre (5,106 kg/ha). Grain of Tribute has a very high test weight (mean of 60.8 lb/bu; 782 kg/m^3^), which is similar to that of Roane (60.2 lb/bu; 775 kg/m^3^) and 4 lb/bu (51 kg/m^3^) higher than that of Coker 9835. Tribute was evaluated for 3 years in the USDA-ARS Uniform Southern SRWW Nursery and ranked third in grain yield among 33 entries in 2000 (79 bu/acre; 5,308 kg/ha), fifth among 43 entries in 2001 (74 bu/acre; 4,962 kg/ha), and first among 40 entries in 2002 (64 bu/acre; 4,300 kg/ha). During the same period, Tribute also was evaluated in the Uniform Eastern SRWW Nursery and ranked third in grain yield among 40 entries in 2000 (81 bu/acre; 5,442 kg/ha), eleventh among 44 entries in 2001 (79 bu/acre; 5,308 kg/ha), and fourth among 44 entries in 2002 (73 bu/acre; 4,905 kg/ha). In all six nurseries, Tribute ranked first in test weight, with overall means ranging from 59.2 to 61.1 lb/bu (762 to 786 kg/cm^3^). Tribute also performed well in tests conducted under 12 environments in Ontario, Canada.

Authorized seed classes of Tribute are Breeder, Foundation, and Certified. Tribute is protected under the amended U.S. Plant Variety Protection Act of 1994 (Application pending). The Department of Crop and Soil Environmental Sciences and the Virginia Agricultural Experiment Station, Blacksburg, Virginia, will maintain Breeder seed. Certified seed of Tribute will be available to producers beginning in autumn 2003.

Progress in breeding Fusarium head blight resistance in soft red winter wheat. [p. 225-227]

C.A. Griffey, J. Wilson, D. Nabati, J. Chen, and T. Pridgen.

A primary goal of our breeding program is to accelerate the development of adapted and commercially viable, FHB- resistant SRWW cultivars by identifying and incorporating diverse types of resistance into elite genotypes. Breeding methods being used to accomplish this goal include topcrossing, backcrossing, DH techniques, and molecular marker genotyping. In 2002, 229 segregating populations were evaluated in a mist-irrigated FHB nursery, inoculated using colonized maize seed, at Mt. Holly, VA. Seventy-seven of these populations (34 %) were advanced on the basis of FHB incidence and severity, agronomic traits, and resistance to other prevalent diseases such as powdery mildew, leaf rust, and glume blotch.

In other field tests, approximately 4,500 headrows (F3-F8 and various backcross generations) were evaluated for agronomic traits and resistance to diseases other than FHB at Warsaw, VA. In addition, approximately 2,800 F5-F7 headrows were evaluated for FHB resistance and agronomic traits in an inoculated, mist-irrigated nursery at Blacksburg, VA. From these headrows, 32 backcross-derived lines and 26 top cross-derived lines were selected for further testing in our scab nursery at Blacksburg and in Observation yield tests at two locations in 2003. Twelve lines from the 2001­02 Observation yield test were selected for further testing in Preliminary wheat trials. Four elite lines were selected for testing in our advance yield trial, and two elite lines will be tested in Virginia's official variety trial. Twelve lines will be tested in the 2002-03 Uniform Winter Wheat FHB Nurseries. Two newly released varieties from the Virginia Tech Small Grains Program, McCormick and Tribute, possess a significant level of scab resistance (Tables 1 and 2).

Progress in transferring type-II resistance into SRWW genotypes has been accelerated via use of the wheat by maize DH system. One DH line, VA01W-476, developed from the cross 'Roane/W14', was found to have good scab resistance in greenhouse and field tests and also has major genes for scab resistance as determined by DNA analysis. A total of 135 DH lines derived from nineteen three-way crosses consisting of diverse scab-resistant parents were selected on the basis of field and greenhouse tests this year and will be evaluated for scab resistance in our inoculated, mist-irrigated nursery at Blacksburg and for agronomic traits at Warsaw.

Type-II resistance from five different sources (Futai8944, Futai8945, Shaan85, VR95B717, and W14) has been backcrossed into seven adapted SRWW backgrounds, and two of the recurrent parents (Roane and Ernie) possess FHB resistance other than type II. A total of 180 BC4F2 and BC5F2 individuals were selected on the basis of scab severity in greenhouse tests and will be evaluated for scab resistance in our inoculated, mist-irrigated nursery at Blacksburg and for agronomic traits and similarity to the recurrent parent at Warsaw. Near-isogenic SRWS lines with type-II resistance are being developed and will facilitate pyramiding of different types of FHB resistance.