TEXAS


TEXAS A&M UNIVERSITY

Texas A & M University Agricultural Research & Extension Center, 6500 Amarillo Blvd, West, Amarillo, TX 79106, USA.

Texas A & M University Agricultural Research & Extension Center, Rt. 7, Box 999, Beaumont, TX 77713, USA.

Texas A & M University Agricultural Research & Extension Center, 17360 Coit Road, Dallas, TX 75252, USA.

Soil & Crop Science Department, Texas A & M University, College Station, TX 77843, USA.

Texas A & M University Agricultural Research & Extension Center, Drawer E, Overton, TX 75684, USA.

Texas A & M University Agricultural Research & Extension Center, P.O. Box 1658, Vernon, TX 76384, USA.

Amarillo.

M.D. Lazar, G.J. Michels, Jr., C.D. Salisbury, W.C. Wang, K.B. Porter, and G.L. Peterson.

Personnel. Jon Simmons left the program for a technical position with the ARS Production and Conservation Laboratory at Bushland. Jie Hu left the program to pursue a medical career. Jill Booker and Giovanni Piccinni obtained new positions at the Amarillo Center in the agronomy and plant pathology projects, respectively. Qingwu Xue graduated from West Texas A&M University with a M.S. degree and left to pursue a Ph.D. degree at the University of Nebraska. Dr. Wen-Chung Wang joined the program, moving from the Dallas Center.

High Plains Crop Year. The principal feature of the 1995-96 crop year was a severe drought. Autumn moisture was adequate, but from 20 December, 1995, through 30 May, 1996, only 0.48 inches of precipitation fell at Bushland. Severe damage also resulted from two freeze events in the spring. Several rainfed nurseries at Bushland were abandoned. Greenbug was a damaging pest, particularly in the eastern Panhandle, for the third year in a row. In dryland variety tests that were harvested, no varieties yielded over 15 bu/acre, but greatest yields were observed for TAM 107, TAM 105, and AgriPro 7510. Irrigated nurseries were provided 28 inches of water, but greatest yields barely exceeded 90 bu/acre. The best varieties under irrigation were Agripro 7510, Ogallala, and TAM 105.

Wheat Breeding. TAM 110 was released during 1996. The pedigree of TAM 110 is `(TAM 105*4/Amigo)*5 //Largo'. TAM 110 is the first U.S. wheat cultivar with resistance to biotype E and I greenbug. Like its related cultivar TAM 107, TAM 110 is susceptible to leaf rust. Therefore, TAM 110 is recommended for production only on the High Plains under rainfed or limited irrigation conditions. TAM 110 has no known resistance to the RWA. In the absence of greenbug infestation, TAM 110 is expected to yield similarly to TAM 107.

Greenbug Resistance. Previously released NILs, differing in response to biotype E, have been demonstrated to have two, distinct, separable effects on aphid development and reproduction. Total nymph production of biotype E on TXGBE273 (resistant) is about one-third that on TXGBE307 (susceptible). Intrinsic rate of growth was consistent over at least three aphid generations continuously maintained on each host. Transfer of aphids after two generations from the resistant to the susceptible host resulted in recovery of the intrinsic rate of growth to a level significantly lower than that of aphids consistently maintained on the susceptible host (about 80 % of the susceptible host). The difference between intrinsic rate of growth on the resistant host and that after transfer to the susceptible host was entirely attributable to differences in reproductive rate. The remaining significant difference in intrinsic growth rate between aphids transferred from resistant to susceptible host and those maintained on the susceptible host was entirely attributable to differences in adult lifespan.

Biotype E-resistance previously reported in the NILs is attributable to the action of at least two genes. These two genes were erroneously referred to by Lazar et al. (1995) as Gb3a and Gb3b. In fact, these genes should be Gb3 (previously named) and Gb7. Both genes are derived from Largo.

College Station and Vernon.

W.D. Worrall, A.K. Fritz, M.E. McDaniel, S. Caldwell, D. Conover, and R. Herrington.

Personnel. Allan Fritz joined the Soil and Crop Sciences department faculty as an Assistant Professor in July, 1996. Dr. Fritz is housed in the Crop Biotechnology Center at College Station, and will be responsible for the south Texas breeding program and the development and utilization of molecular markers in wheat.

Russian wheat aphid-research update. David Worrall, Allan Fritz, and Steve Caldwell continue to work on the inheritance of RWA resistance in triticale. Steve Caldwell has identified a marker from PI386156 that explains approximately 60 % of the variation observed for RWA resistance in a cross with NE88T222, a susceptible line. That marker has been mapped to chromosome 4R (unpublished). We also determined that the wheat greenbug resistance gene Gb4 maps on chromosome 7D. Efforts to tag this gene with molecular markers are underway.

Dallas.

David Marshall and Russell L. Sutton.

The 1995-96 small grains growing season in the Texas Northern Blacklands was characterized by a hard winter and a lack of rainfall. On four separate occasions, the temperature remained below freezing for 3 or more days. Those time periods were 5-8 January (lowest temperature 13 F on 7 January), 17-20 January (lowest temperature of 14 F on 19 January), 1-6 February (lowest temperature of 6 F on 4 February), and 7-10 March (lowest temperature of 15 F on 9 March). From October through May, the Northern Blacklands typically receive about 23 to 25 inches of rain. From October, 1995, through May, 1996, the Northern Blacklands received only about half that amount (13.3 inches at Prosper and 11.6 inches at Dallas). This combination of lack of rain and low temperatures resulted in winterkilling of some tender lines and varieties. However, the low temperatures and sparse rainfall also kept most diseases and insect pests from building up large populations. As a result, diseases such as leaf rust, Septoria, and powdery mildew were insignificant, if not totally absent in the Northern Blacklands.

The highest-yielding hard wheat varieties were TAM 202, Ogallala, and TAM 300. Soft wheats with the highest yields were Pioneer 2580, Clemens, and Pioneer 2684.

Personnel. David Marshall will be on sabbatical leave in New Zealand from April through October, 1997.

Overton.

L.R. Nelson, S.L. Ward, and J. Crowder.

Wheat grain yields in east Texas in 1996 were extremely high with many plot yields near 100 bu/acre. These yields were the result of a very dry growing season during the grain filling period. Conditions were not conducive to disease buildup and allowed the small grains to reach their full genetic potential for grain yield. The highest-yielding cultivars at Overton were Sawyer (96 bu/acre) and Pioneer 2548 (92 bu/acre). At DeKalb, TX, Clemons produced a grain yield of 109 bu/acre. The only location in the state that leaf rust data could be recorded was at Overton, and this information was very useful to the Texas wheat breeding program. Results from a diallel analysis for S. nodorum resistance indicated that additive gene effects were more important than dominance and incubation period (IP), latent period (LP), and percent necrosis were polygenetically inherited. In this study, IP was estimated to be controlled by two to three genes, LP by three genes, and necrosis by one to four genes. Breeding lines SWM14240 and TX18NT demonstrated good resistance and will be used in the wheat breeding program in an attempt to pyramid genes for resistance to S. nodorum. Seven drought-tolerant wheat germplasms were released through cooperative research.

Publications.

Baker JL, Bates RP, and Nelson LR. 1996. Registration of "Bates" rye. Crop Sci 36:810.

Lazar MD, Peterson GL, and Hu J. 1995. Multigenic inheritance of biotype-E-greenbug resistance in wheat. Plant Breed 114:492-496.

Du CG and Nelson LR. 1996. Pyramiding genes conditioning resistance to Stagonospora nodorum in wheat. Agron Abstr p. 88.

Lazar MD, Bean BW, and Salisbury CD. 1996. Vernalization response of west Texas wheat varieties. Texas J Agric Natur Resour 9:43-49.

Lazar MD, Worrall WD, Porter KB, and Tuleen NA. 1996. Registration of eight closely related wheat germplasm lines differing in biotype E greenbug resistance. Crop Sci 36:1419.

Lazar MD, Salisbury CD, Worrall WD, Porter KB, Ronney WL, Marshall DS, Mcdaniel ME, Nelson LR, and Tuleen NA. 1996. Registration of seven related wheat germplasms differing in irrigation response. Crop Sci 36:818-819.

Marshall D, Gardenhire JH, Sutton RL, Rooney LW, Lazar MD, McDaniel MD, Nelson LR, and Worrall WD. 1995. Registration of `TAM 300' wheat. Crop Sci 35:592-593.

Nelson LR, Crowder J, and Ward S. 1996. Wheat grain variety tests at Overton for 1993-94 and 2-year means. In: Overton Forage-livestock Field Day Report-1996. p. 63-64.

Nelson LR, Du C, Crowder J, and Ward S. 1996. Wheat grain variety tests at Dekalb for 1994-95. In: Overton Forage-livestock Field Day Report-1996. p. 67-68.

Ward S, Crowder J, Du C, and Nelson LR. 1996. Wheat forage yields at Overton for 1994-95 and 3-year means. In: Overton Forage-livestock Field Day Report-1996. p.9-10.

Ward S, Crowder J, and Nelson LR. 1996. Triticale forage yields at Overton for 1994-95. In: Overton Forage-livestock Field Day Report-1996. p.11-12.


UTAH


UTAH STATE UNIVERSITY

Plant Science Department, Logan, UT 84321, USA.


Spring wheat

R.S. Albrechtsen.

Production, diseases, and insects. A 1996-harvested Utah spring wheat acreage that was slightly larger than that of the previous year was more than offset by a 15-bushel lower yield per acre (60 bushels versus 75 bushels), resulting in a lower total production. Spring wheat diseases were generally minor. Losses from the cereal leaf beetle and the RWA were spotty but generally minimal.

Breeding program. We are reducing our effort on the breeding program, because of our small spring wheat acreage. We are able to identify well-adapted cultivars from the Western Regional Spring Wheat Nursery and other breeding programs in the west.

Cultivars. Rick (HRSW) continues to perform well under both irrigated and non-irrigated conditions. Penawawa (SWSW) does well under irrigation.

Dr. Bruce Bugbee performed the leading role in development and release of the first dwarf HRSW (named USU-Apogee) developed specifically as an improved cultivar for bioregenerative life-support systems in space, under highly controlled environments. USU-Apogee is shorter and higher-yielding than Yecora Rojo and Veery-10, the short field genotypes previously used in controlled environment production. USU-Apogee develops rapidly, with heads emerging 23 days after seedling emergence in continuous light and a constant temperature of 25 C. The yield advantage of USU-Apogee is greatest under such conditions favorable to rapid development.

Winter wheat.

D.J. Hole.

Production, diseases, and insects. The harvested acreage of winter wheat in 1996 was 145,000 acres, up 5,000 acres from 1995. Average yields were 10 bu/acre lower at 40 bu/acre, resulting in production of 5.8 million bushels, down from the 1995 record crop.

There were some natural infections of dwarf bunt, although resistant cultivars continue to hold that disease in check. There were three reports of flag smut, all on Weston wheat that had been saved and planted for a number of years. Infestations of the cereal leaf beetle and RWA were light. The Utah Karnal bunt survey found no incidence of the disease in the 1995 or 1996 crops.

Breeding program. Breeders headrows were harvested for a hard white winter wheat that has been tested under the designation UT1944-158. Foundation fields of UT1944-158 have been planted, but no decision to release it has yet been made by the experiment station.

Publications.

Hole DJ, Albrechtsen RS, Clawson SM, and Thompson VD. 1996. 1995 Utah small grains performance trials. UAES report 154.

Hu CJ, Hole DJ, and Albrechtsen RS. 1996. Barley chromosome location and expression of dwarf bunt resistance in wheat addition lines. Plant Dis 80:1273-1276.

Hole DJ, Albrechtsen RS, and Clawson SM. 1996. Registration of `Garland' Wheat. Crop Sci 36:208.


VIRGINIA


VIRGINIA POLYTECHNIC INSTITUTE AND STATE UNIVERSITY

Departments of Crop and Soil Environmental Sciences and Human Nutrition, Foods and Exercise, Blacksburg; VA 24061; USA.

Virginia wheat production in 1996.

C.A. Griffey and D.E. Brann (Department of Crop and Soil Environmental Sciences).

Growing conditions. The 1995-96 wheat growing season was colder and wetter than normal, and much of the wheat acreage was planted and harvested beyond the optimal period. The November-December period, when most of the crop was planted, was 100 growing-degree days less than normal and resulted in reduced plant emergence and tillering. Colder than normal temperatures continued through March with much of the wheat entering the jointing stage with only the main stem and one additional tiller. Lack of tiller development was the major yield-limiting factor in most wheat fields. Leaf and spike diseases, such as powdery mildew, glume blotch and scab were also more severe than normal due to the cool, wet weather. Head emergence was about a week later than normal. Frequent rains occurring after crop maturity delayed harvest and resulted in reductions in test weight and grain quality. Although temperatures dropped well below freezing during the winter months, little winterkill was observed because of protection by a record snow-coverage.

Production. According to the Virginia Agricultural Statistics Service, 300,000 acres (121,500 ha) of soft red winter wheat were planted in Virginia in 1995, with 275,000 acres (111,375 ha) being harvested for grain. An average yield of 53 bu/acre (3,560 kg/ha) was obtained in 1996, which was 11 bu/acre lower than the state yield-record set in 1995. Total wheat production in 1996 was 14.6 million bushels (397,000 metric tons). Although the number of acres harvested did not change from 1995, total production was 3 million bushels less in 1996, because of lower yields.

Virginia Wheat Yield Contest. Eight wheat producers representing six counties participated in the 1996 Virginia Wheat Yield Contest. David Hula of Renwood Farms, Charles City Co., had the highest-yielding wheat at 132 bu/acre (8,870 kg/ha) over a minimum area of three acres (1.2 ha). Producers in four counties entered the Virginia No-Till Wheat Contest. Randolph and Louis Aigner of Oakland Farms, Henrico Co., had the highest yield with 103 bu/acre (6,920 kg/ha) over a minimum area of three acres (1.2 ha).

State cultivar tests. Ten public and 23 private wheat cultivars were evaluated at six locations in Virginia in 1996. The cultivars Pocahontas, Coker 9663, and Baytan-treated Wakefield and Jackson yielded above the test average with yields ranging from 87-90 bu/acre (5,845-6,047 kg/ha). Other cultivars with average yields ranging from 79 to 85 bu/acre (5,308-5,711 kg/ha) and not significantly different from the overall cultivar mean were Baytan-treated Pioneer 2580, 2684, 2691, 2643; FFR 555W, 523W; Coker 9835; Hoffman 89; and Vitavax-treated Madison, GA-Gore, FFR 568W, Featherstone 520; and AgriPro Foster, Mason, and Elkhart. Test weight means for the six locations ranged from 53.8 at Blacksburg to 58.5 lb/bu (692-753 kg/m3) at Warsaw, Virginia, with a mean of 56.5 lb/bu (727 kg/m3) over all locations. At Warsaw, where the crop was harvested on time and prior to frequent rains, test weights ranged from 56.4 to 61.3 lb/bu (726-789 kg/m3). Cultivars with average test weights of 58.0 lb/bu (746 kg/m3) or higher over locations were Coker 9663, Hoffman 89, Hoffman 95, Coker 9803, Pioneer 2684, and Elkhart.

Disease incidence and severity. As a result of cooler temperatures, powdery mildew developed to epidemic levels and persisted throughout much of the grain-fill period. Baytan-treated susceptible cultivars had severities as high as 50 %, and mildew was observed on previously resistant cultivars such as Coker 9904. As normally observed, leaf rust developed late in the season with moderate severity on flag leaves. Leaf and glume blotch were moderately severe as a result of frequent rains during May and June. Scab was severe and resulted in a considerable reduction in grain quality in winter durum tests grown in the western part of the state.

Cultivar release. Pocahontas, formerly designated VA 93-52-60, was released by the Virginia Agricultural Experiment Station in 1997. The name Pocahontas was selected as a tribute to all native Americans and, particularly, to the Powhatan princess Pocahontas, who devoted her life to promoting peace. Pocahontas was derived as an F5-head selection from the cross 'Wheeler'*2/C39//'Saluda'. The C39 parent (genes Pm2, Pm4b, and Pm6) originated in England and was selected from the 1982 International Winter Wheat Mildew Nursery as a source of resistance to powdery mildew. Pocahontas is an early-heading, high-yielding, awnleted SRWW with resistance to powdery mildew. Head emergence is 1-2 days earlier than that of the most widely grown early wheats and 4 days earlier than Jackson and FFR 555W. Plant height of Pocahontas is 35 inches, which is similar to FFR 555W and 1-2 inches shorter than that of Jackson. Pocahontas has good straw strength and is superior to Jackson in this aspect. Based on parentage and limited data, winter hardiness of Pocahontas is moderate, being similar to that of Saluda and Jackson. Average grain test weight of Pocahontas is 57.7 lb/bu and is similar to that of Jackson. Pocahontas has very good milling quality with high flour yields, and baking quality is satisfactory. Milling quality is superior and baking quality is similar to that of Saluda.

Pocahontas is resistant to the prevalent strains of powdery mildew in the mid-Atlantic region and has a moderate level of resistance to soilborne viruses and to leaf and glume blotch. The cultivar is moderately susceptible to the prevalent races of leaf rust and to barley yellow dwarf virus. Although Pocahontas exhibits resistance to five races of stem rust, it is susceptible to the most prevalent race TNMK. Pocahontas is resistant to Hessian fly biotypes GP and E but is susceptible to the most prevalent biotype L.

In 18 tests conducted in Virginia during 1994-96, Pocahontas had an average grain yield of 84 bu/a, which was not significantly different from the highest yielding cultivar. Among released cultivars, Pocahontas ranked first, seventh, and second in grain yield in 1994, 1995, and 1996, respectively. In variety trials conducted in other states in 1996, Pocahontas was ranked among the top 10 lines for grain yield in two trials in South Carolina, five trials in Georgia, four trials in Maryland, one trial in New Jersey, and one trial in Pennsylvania. Pocahontas was evaluated for 2 years (1994 and 1995) in the Uniform Southern Soft Red Winter Wheat Nursery and in the Uniform Eastern Soft Red Winter Wheat Nursery in 1995. Pocahontas is most adapted to the mid-Atlantic and southern regions. The Virginia Crop Improvement Association will be responsible for seed distribution through the Foundation Seed Farm at Mount Holly, Virginia.

Winter durum wheats in Virginia!

A.O. Abaye, C.A. Griffey, and D.E. Brann.

Historically durum wheats, mainly spring-habit genotypes, have been grown in the upper Great Plains states including North and South Dakota, Minnesota and Montana, and also in Arizona. SRWWs are typically grown in the eastern U.S. A durum mill and pasta-manufacturing plant recently were opened in northwestern Virginia, which has created the opportunity for Virginia wheat producers to grow winter durum wheat. More than 60 winter durum cultivars and experimental lines of diverse origin have been evaluated during the past 3 years at four locations in Virginia. Three of the test sites (Montgomery, Orange, and Clarke Cos.) were in the western part of the state and Warsaw (Richmond Co.) is in the northeastern part of the state. Among the genotypes tested, three were from Hungary, two from Romania, three from France, two from Turkey, three from Syria, two from Mexico, nine from Ukraine, and 35 from the U.S.

The main objective of these studies was to examine the feasibility of successfully producing winter durum wheat in Virginia. The specific objectives were to assess genotypes for adaptation including winter hardiness, disease resistance, grain yield, and quality. Thirty-two winter durum and six SRWW checks were evaluated in replicated tests at three locations in western Virginia in 1996. Across locations, grain yields of the best durum genotypes were 15-30 % lower than the average yield of the SRWW genotypes. The durum line, N1013/84, from the Ukraine had the highest average grain yield (68.6 bu/acre = 4,610 kg/ha), and grain yields of 43, 67, and 96 bu/acre were obtained at the three locations. Overall, winter durum genotypes from the Ukraine were most productive in Virginia. In terms of quality (test weight, 1,000-kernel weight, protein concentration, and falling number), some durum genotypes from the Ukraine and Hungary performed within and above the acceptable range compared to North Dakota durum. However, kernel vitreousness was below the acceptable range for all locations except for Orange. The winter durum genotypes will be evaluated at four locations in 1997.

Commercial production of winter durum wheat in Virginia will depend on the feasibility of consistently producing a crop of satisfactory quality and an economic advantage obtained from a higher price per bushel to compensate for lower yield potential compared with SRWWs.

Effect of T1BL-1RS translocation on milling and baking quality of soft red winter wheat.

J.M. Johnson and C.H. Harris (Department of Human Nutrition, Foods and Exercise), and C.A. Griffey.

Soft red winter wheat yield and disease resistance have been improved by the introduction of rye chromatin in the breeding of certain varieties. Rye chromosome 1, or segments of this chromosome, have been introgressed into many soft red winter wheats via a substitution for chromosome 1B and are referred to as T1BL-1RS translocations.

During the 1994 and 1995 growing seasons, this laboratory evaluated eleven SRWW genotypes with or without T1BL-1RS that were grown at Warsaw and Blacksburg, VA. An ELISA test was used to confirm the presence or absence of T1BL-1RS. Genotypes without T1BL-1RS and selected as controls were Saluda, FFR 555W, Massey, and VA93-54-209. Experimental lines with T1BL-1RS were VA92-52-22, VA93-52-55, VA93-54-185, VA93-54-211, VA93-54-258, VA93-54-241, and VA93-54-418. Genotypes VA93-54-209 and VA93-54-211 are sister lines.

Grain harvested from experimental plots at Warsaw and Blacksburg was tempered to a moisture content of 14 % and milled in a Brabender Quadramatic Junior mill. Protein content was determined by the Kjeldahl method using 5.7 % nitrogen as the basis for calculation of total protein. Mixing tolerance of the flour was measured by the Brabender Farinograph using the mixing time stability, or the time at which the dough falls below 500 Brabender units, with longer time indicating a stronger and more tolerant dough to mixing. Mixing tolerance index measures the decline in Brabender units after 5 min of mixing. Baking tests included cakes and cookies made according to the standard formulae of the American Association of Cereal Chemists.

The presence of T1BL-1RS had an inconsistent effect on protein content of the flour. For the 1994-95 growing season, wheats with T1BL-1RS from Blacksburg were higher in protein content, although no difference in protein content was observed among wheats from Warsaw. Environment was suggested to be a more important factor than the presence of T1BL-1RS in determining protein concentration. Dough from flour of the T1BL-1RS wheat VA93-54-211 had a greater stability to mixing than did its sister line (VA93-54-209) without T1BL-1RS. The T1BL-1RS sib was markedly more tolerant to mixing for flour extracted from grain grown at Warsaw.

Cookies made with flours of T1BL-1RS wheats had a lower spread and stack height than cookies from flours of control wheats without T1BL-1RS. However, cakes prepared with flours of T1BL-1RS wheat were significantly higher in volume and more tender and compared very favorably with cakes made from commercial flours that are considered industry standards. Results indicated that flours of T1BL-1RS SRWW is well suited for cakes and cake mixes and could possibly become a premium wheat when purchased for cake flour. These results suggest that assessment of baking quality of SRWW based primarily on cookie spread likely will fail to identify specific genotypes suited for many of the other broad-spectrum uses of SRWW.


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