VIRGINIA
VIRGINIA POLYTECHNIC INSTITUTE AND STATE UNIVERSITY
Department of Crop and Soil Environmental Sciences 1, Blacksburg, VA 240610404, USA.
J.J. Paling, C.A. Griffey, W.E. Thomason, E.L. Stromberg, J.
Chen, D.M. Tucker, T.H. Pridgen, and E.G. Rucker.
J.J. Paling, C.A. Griffey, and W.E. Thomason.
Growing conditions. Weather conditions in 2005 were favorable for planting and growing wheat. Warm temperatures and near normal rainfall occurred through October and November during planting time. Temperatures then became colder and precipitation was slightly below normal for much of the Commonwealth during the winter. Cold temperatures in eastern and southern Virginia during the winter months impeded tillering and resulted in some winter injury. In contrast to 2004 where abnormally high temperatures and dry conditions in May had a deleterious impact on grain fill, yield and test weight, an extended period of cool temperatures during spring 2005 resulted in a longer than average grain fill period, high grain yields, and record test weights in wheat harvested timely. However, delayed senescence and grain dry down in some varieties resulted in later harvest, which was further hindered by persistent rain showers at many locations in eastern Virginia.
Disease and insect incidence and severity. Stripe rust, which rarely had been identified and only in isolated sites in Virginia, was widespread in 2005 and fungicide control was needed in susceptible varieties in some locations. Incidence was moderate to severe in susceptible cultivars at Painter on the Eastern Shore and at Warsaw in Eastern Virginia. Susceptible lines were also infected at Blacksburg in the southwestern part of the state. Disease severity ratings and disease reaction type (resistant to susceptible) were obtained on all released cultivars and experimental lines in test plots grown at Painter in 2005. Powdery mildew incidence was lower than usual for the second consecutive year in the Eastern Shore and Coastal Plain region. Leaf rust infection was moderate on susceptible cultivars grown in research yield trials at Blacksburg and moderate to high at Warsaw in eastern Virginia. Cultivars such as Sisson and USG3209 having gene Lr26 and McCormick having gene Lr24 were susceptible to leaf rust. The incidence of scab was low in 2005. Aphids were present in plots at several regions during the autumn, whereas cereal leaf beetle populations were relatively low during the spring. Barley yellow dwarf virus infection was moderate at four of the testing locations, and results from DNA tissue analysis conducted by USDA-ARS at Purdue University indicated presence of only the MAV strain.
Production. The NASS Agricultural Statistics Service reported in January 2006 that Virginia wheat producers harvested 160,000 acres (64,800 ha) of winter wheat for grain in 2005. This was slightly less than the 180,000 acres harvested in 2004. However, grain yields averaged 63.0 bu/acre (4,230 kg/ha) in 2005, 8 bu/acre (540 kg/ha) more than in 2004 and much more than the very low 46 bu/acre (3,090 kg/ha) in the 2003 FHB epidemic year. Total wheat production in 2005 for the Commonwealth was 10.08 x 106 bushels (274,000 metric tons), 180,000 bu (4,900 metric tons) higher than in 2004.
State cultivar tests. A total of 71 entries were evaluated at seven locations across the Commonwealth in 2005. Included in this total were 34 released cultivars and 37 experimental lines (31 developed at Virginia Tech). Average grain yields ranged from 61 to 80 bu/acre (4,100-5,375 kg/ha) with an over location test average of 72 bu/acre (4,840 kg/ha). Wheat cultivars with yields significantly above the test average were SS MPV 57, SS 560, Renwood 3260, USG 3209, Featherstone 176, 3706, Pioneer 26R24, SS 520, and V9412. Fourteen experimental lines, all from Virginia, also yielded significantly higher than the seven-location test average. Yields from these highest producing cultivars and experimental lines ranged from 75 to 80 bu/acre (5,040-5.375 kg/ha). Average test weights of wheat lines ranged from 57.5 lb/bu (740 kg/cu m) to 60.3 lb/bu (775 kg/cu m) with a test average of 59.0 lb/bu (760 kg/cu m). Average test weights of most of wheat lines entered in 2005 were similar to the overall average. Indeed, only three entries (one cultivar and two experimentals) produced wheat with test weights significantly higher than the average.
Of the seven test sites in 2005, the conventional tillage tests grown at Warsaw and Orange produced the highest average yields and test weights (Table 1). Both yield and test weights were reduced at Painter because of stripe rust and harvest delayed nearly 2 weeks due to rain showers after maturity. Excellent yields also were obtained at Blacksburg, however, test weights were reduced as a result of harvest delayed 1 week due to rain.
| Location | Yield | Test weight | ||
|---|---|---|---|---|
| bu/acre | kg/ha | lb/bu | kg/cubic m | |
| Blacksburg - Kentland Farm Southwest VA | 86 | 5,780 | 58.6 | 755 |
| Blackstone - Southern Piedmont AREC | 49 | 3,290 | 60.5 | 780 |
| Holland - Tidewater AREC | 60 | 4,030 | 56.3 | 725 |
| Orange - Northern Piedmont AREC | 90 | 6,050 | 60.7 | 780 |
| Painter - Eastern Shore AREC | 77 | 5,170 | 54.5 | 700 |
| Shenandoah Valley | 54 | 3,630 | 60.1 | 775 |
| Warsaw - Eastern Virginia AREC | 88 | 5,910 | 62.7 | 805 |
| Seven location average | 72 | 4,840 | 59.0 | 760 |
Warsaw no-till wheat test. An excellent stand was obtained in the autumn of 2004. Tillering was lower than normal going into early spring, but rebounded later with the favorable growing conditions. Grain yields averaged 90 bu/acre (6,050 kg/ha) with an average test weight of 62.1 lb/bu (799 kg/cu m). Ten entries, five cultivars, and five Virginia experimental lines yielded significantly higher than the test average. Yields of these ten entries ranged from 98 to 104 bu/acre (6,585-6,990 kg/ha). Released cultivars yielding higher than the test average were SS MPV 57, 3706, SS 560, Chesapeake, and SS 520. In general, wheat grown in the no-till test at Warsaw performed very well in 2005 despite the occurrence of epidemic levels of both leaf rust and stripe rust in this nursery.
Virginia wheat yield contests. Nine entries were in the 2005 Virginia wheat yield contests. Seven of the entries were grown no-till and two using conventional tillage. Four of the five highest yields were obtained from entries grown in Charles City County, and the seven no-till entries resulted in the highest yields. Average yield of no-till entries was 20 percent higher than in 2004. All of the contestants planted certified seed after a previous corn crop.
The highest yield of all entries was obtained by Archer H. Ruffin Jr. of Charles City County, who produced 123 bu/acre (8,265 kg/ha) of 'Tribute' wheat. The other entries from Charles City county were; Timothy Ruffin, 110 bu/acre (7,390 kg/ha) of Pioneer 26R15; David Black, 108 bu/acre (7,255 kg/ha) of Tribute; Darrell Harold, 102 bu/acre (6,855 kg/ha) of Renwood 3260; and Renwood Farms Inc., 96 nu/acre (6,450 kg/ha) of USG 3137. Roger Calhoun of King and Queen County produced 97 bu/acre (6,520 kg/ha) of Tribute and David Hula of James City County grew 92 bu/acre (6,180 kg/ha) of Renwood 3260. In the conventional till fields, Clifton Brann of Northumberland County harvested 84 bu/acre (5,645 kg/ha) of McCormick and John Jenkins of Westmoreland County harvested 81 bu/acre (5,440 kg/ha) of Tribute. Congratulations to all contestants in the Virginia Wheat Yield Contest for growing wheat crops with grain yields well above the commonwealth average.
Winter durum wheat. The Virginia Tech small grains breeding and genetics program has been working on developing winter durum wheat lines since 1998. In 2004, 49 experimental lines of winter durum wheat developed at Virginia Tech were planted in an observation yield nursery at Warsaw, VA. These lines were evaluated for yield, test weight, winter survival, and disease resistance in the field trial and in greenhouse disease screening tests. Overall, test weights of the experimental lines averaged 61.6 lb/bu (793 kg/cu m), ranging from 58.9 to 64.3 lb/bu (758 to 828 kg/cu m). Average test weight of the winter durum check cultivars in this observation nursery was 60.7 lb/bu (781 kg/cu m). Seventeen of the 49 experimental durum lines having good winter hardiness and overall field performance were advanced and planted in replicated yield tests at two locations in Virginia and one location in Kansas during autumn 2005. The average test weight of these 17 selected lines was 62.6 lb/bu (806 kg/cu m) and ranged from 60.0 to 64.3 lb/bu (772 to 828 kg/cu m). Their average grain protein concentration was 15.6 %, with a range from 14.4 to 16.9 %.
Hard red and hard white winter wheat breeding and research. Virginia Tech's Small Grains Breeding and Genetics program has been evaluating and developing hard red and hard white winter wheat for several years. Select elite bread wheat cultivars and experimental lines from other breeding programs were tested in replicated yield trials and lines developed at Virginia Tech were evaluated in non-replicated nurseries in 2005. Fifty-two elite bread wheat lines were tested at Blacksburg, Warsaw, and Painter Virginia in 2005. Average yield of these entries was 70.8 bu/acre (4,757 kg/ha) and ranged from 51.9 to 80.0 bu/acre (3,487-5,375 kg/ha). Average test weight was 59.3 lb/bu (763 kg/cu m) and ranged from 55.6 to 61.7 lb/bu (716 to 794 kg/cu m). Of the 52 entries harvested in 2005, grain from 24 cultivars and experimental elite lines harvested at Warsaw in eastern Virginia were sent for milling and baking quality analysis.
In 2004-05, a nonreplicated observation yield nursery (73 experimental lines and 7 checks) of bread wheat lines, many developed at Virginia Tech, was planted and harvested at two locations (Blacksburg and Warsaw). Lines were evaluated for agronomic performance including yield, winter survival, test weight, disease resistance, and grain quality. The average yield over the two locations for the experimental lines was 60.9 bu/acre (4,092 kg/ha) and ranged from 39.1 to 78.5 bu/acre (2,627 to 5,274 kg/ha). Average test weight was 60.4 lb/bu (777 kg/cu m) and ranged from 57.8 to 62.6 lb/bu (744 to 806 kg/cu m). The average yield and test weight of the hard winter wheat check cultivars was 50.9 bu/acre (3,420 kg/ha) and 60.7 lb/bu (781 kg/cu m). Sixteen experimental lines were selected and planted in replicated yield nurseries in Blacksburg and Warsaw in the fall of 2005. Yields of these 16 lines averaged 70.7 bu/acre (4,750 kg/acre) and ranged from 45.8 to 82.4 bu/acre (3,077-5,536 kg/ha) with an average test weight of 60.6 lb/bu (780 kg/cu m), ranging from 56.3 to 64.5 lb/bu (725 to 830 kg/cu m). These 16 lines also were evaluated for milling and baking quality.
Bread wheat breeding and research in 2006. A bread wheat elite test with 32 entries was planted at three locations in the autumn of 2005. The experimental bread wheat lines selected from the 2005 observation nursery were planted in replicated nurseries at Blacksburg and Warsaw. Bread wheat observation yield nurseries, 142 total plots with more than 100 experimental lines developed and/or selected at Virginia Tech, were planted at Warsaw and Blacksburg during autumn 2005. In addition, 50 elite hard winter wheat lines from Colorado State University and 42 lines included in Kansas State University's Advanced Yield Nursery were planted in separate replicated yield nurseries at Warsaw, Virginia. Entries in the USDA-ARS Uniform Bread Wheat Nursery also will be evaluated in replicated tests at two locations in Virginia.
W. E. Thomason and E. L. Stromberg.
Hard wheat and certain strong gluten soft wheat are suitable for use in making bread and dough products. Because the market exists for bread wheat and because it is usually of higher value than soft wheat ($0.40 or more per bushel), growers are interested in using adapted varieties and developing agronomic techniques to grow bread wheat in the mid-Atlantic region.
Two trials were established using five promising bread wheat cultivars: Karl 92 (a Kansas HRWW cultivar), Amelio (a French bread wheat whose marketing rights in this region are owned by the Virginia Identity Preserved Grains group), Tam 110 (a HRWW developed in Texas), Lakin (a Kansas HWWW cultivar), and Renwood 3260 (a SRWW developed in Virginia). These cultivars were chosen to represent the breadth of diversity of potential bread wheat genetics and diverse patterns of disease resistance. Experimental locations were at the Eastern Virginia Agricultural Research and Extension Center, Warsaw, VA, and at the Eastern Shore Agricultural Research and Extension Center, Painter, VA, in 2004-05. Seeding rates were 375 seeds/m2 based on research for SRWW cultivars. A split-plot experimental design was employed such that Baytan 30® (triademenol) seed treatment at 94 g/kg of seed was applied to one-half of the planted plots, resulting in one block of varieties protected from autumn infection of powdery mildew and another block with only genetic resistance. Quilt® (azoxystrobin + propiconazole) was applied at 203 g/ha to one-half of all plots at GS 37 (flag-leaf emergence) to assess the efficacy of chemical control of powdery mildew, both with and without previous seed treatment. In 2005, disease pressure was low and the growing environment was favorable for high yields and test weights. Seed treatment had no effect on spring disease levels. Application of a fungicide did lower disease scores, but did not affect grain yield or test weight at either location. Further information is available on the web at: http://www.grains.cses.vt.edu/grains/Research/BW_disease_05.htm.
Two individuals on the small grains breeding project completed advanced degrees at Virginia Tech in 2005 and a new Research Associate joins the program in March 2006.
Dr. Jianli Chen received her Ph.D. degree in Crop and Soil Environmental Sciences with a specialty in Plant Genetics and Breeding in December 2005. Her dissertation title was "Validation and Marker-Assisted Selection of Two Major Quantitative Trait Loci Conditioning Fusarium Head Blight Resistance in Wheat". One of dissertation derived papers "Validation of Two Major Quantitative Trait Loci for Fusarium Head Blight Resistance in Chinese Wheat Line W14" has been published in the Journal of Plant Breeding 125: 99-101, 2006. Jianli has been a Research Associate and co-principal investigator in the Fusarium head blight (FHB) project of the Small Grains Breeding and Genetics Program at Virginia Tech since 1997. Jianli coordinates the FHB research program, and has been working on breeding, selection and development of FHB resistant wheat and barley cultivars. Dr. Chen is continuing her career at Virginia Tech where she will continue to lead the program's FHB breeding project, including mapping and marker-assisted selection (MAS) for FHB resistance.
Dominic Tucker completed his M.S. program in May 2005. His thesis title was "Validation, Saturation, and Marker-Assisted Selection of Quantitative Trait Loci Conferring Adult Plant Resistance to Powdery Mildew in an Elite Wheat Breeding Population". The major objective of his research was to identify molecular markers associated with partial resistance or adult plant resistance in the cultivar 'USG 3209'. Dominic has a paper titled "Potential for Effective Marker-Assisted Selection of Three Quantitative Trait Loci Conferring Adult Plant Resistance to Powdery Mildew in Elite Wheat Breeding Populations" in press in the Journal of Plant Breeding.
Dominic is continuing his education towards a Ph.D. at Virginia Tech. He is working on a collaborative project with Iowa State University, The Ohio State University, and Virginia Polytechnic Institute and State University on mapping and cloning Phytophthora sojae genes in soybean under the direction of Dr. M.A. Saghai Maroof, Professor, Department of Crop and Soil Environmental Sciences at Virginia Tech.
Patricia Gundrum joins the Virginia Tech small grains breeding and genetics program as a Research Associate in March. She will be working with plant diseases, particularly the fungal pathogens affecting small grains. Patricia received a B.S. degree in Plant Sciences from West Virginia University in 1989 and a M.S. in Plant Pathology from West Virginia University in 1999, Thesis title "A Biological Comparison of Discula destructiva Isolates from Four Geographic Locations". Patricia was with the USDA Forest Service from 1991 to 1998. She was with the Appalachian Integrated Pest Management from 1991-92 and in State and Private Forestry from 1992 to 1998. From 1998 to the present she has been a Plant Pathologist at the USDA-ARS Appalachian Fruit Research Station at Kearneysville, West Virginia.