GrainGenes

ITEMS FROM THE UNITED STATES

SOUTH DAKOTA

SOUTH DAKOTA STATE UNIVERSITY AND THE USDA-ARS NORTHERN GRAIN INSECT RESEARCH LABORATORY (NGIRL).
Plant Science Department, Brookings, SD 57007 USA.

A.M.H. Ibrahim, S.A. Kalsbeck, R.S. Little, S. Malla, E. Babiker, M. Langham, T. Cheesbrough, Howard J. Woodard, Anthony Bly, and Brian Pavel (South Dakota State University) and L. Hesler, W. Riedell, and S. Osborne (USD-ARS-NGIRL).

Winter wheat breeding and genetics. [p. 185-186]

A.M.H. Ibrahim, S.A. Kalsbeck, R. S. Little, S. Malla, and E. Babiker.

Crop report and testing sites. Winter wheat production in South Dakota in 2005 was estimated at 63.4 x 10^6^ bushels from 1.44 million harvested acres (1.5 million planted acres), for an average of 44 bushels/acre. In 2005, the winter wheat breeding program tested at eight sites throughout South Dakota. These environments included Aurora and Brookings (Brookings Co.), Platte (Douglas Co.), Highmore (Hyde Co.), Selby (Walworth Co.), Winner (Tripp Co.), Wall (Pennington Co.), the Northeast Research Farm near Watertown (Codington Co.), Kennebec (Lyman Co.), and both irrigated and dry land environments at the Dakota Lakes Research Farm east of Pierre (Hughes Co.). Crop performance testing also was conducted at five sites west of the Missouri River in cooperation with John Rickertsen and Bruce Swan (SDSU West River Agricultural Research and Extension Center, Rapid City). The crop was planted 11 September, 2004, at Selby and the Northeast Research Farm; 17 September at Dakota Lakes Research Farm and Highmore; 20 September at Winner, Wall, and Platte; and 4 October at Brookings. When autumn stand counts were taken at all locations, the crop was at the four leaf stage with very good crown development and as many as four tillers or more per plant. Above average temperatures in February and March led the South Dakota Field Office of USDA's National Agricultural Statistics Service to rate the winter wheat crop as 81 percent good to excellent the first week of April. A continuation of great growing conditions in May resulted in major disease development. Temperature and moisture conditions in late May resulted in the development of powdery mildew (a condition normally only seen in the greenhouse) at Dakota Lakes. Fusarium had blight and tan spot were both severe in some parts of the state. The severity of disease occurrences (stripe rust, FHB, tan spot, stem rust, powdery mildew, take-all, and WSMV) allowed for data collection and evaluation in many sites in the breeding program. The nursery at Selby was abandoned. The winter wheat seedlings were suppressed because of extreme pressure from volunteer spring wheat regrowth in that site. The spring wheat stubble nursery at Dakota Lakes was not harvested because of severe lodging and poor quality of seed samples.

Foundation seed increase. Foundation seed of two lines (SD97W609 and SD98102) is being increased for potential release in 2006. SD97W609 was developed from the cross 'Abilene/Karl' and is a semidwarf, early maturing (similar to Wendy) HWWW with good winter survival ability and excellent yield potential. SD97W609 has excellent baking quality in predictive testing and in large-scale testing in the 2005 Wheat Quality Council. This line has high test weight, intermediate levels of polyphenoloxidase enzyme, average protein, very short coleoptile, and good sprouting resistance. SD97W609 is moderately resistant to stem rust and WSMV and is moderately susceptible to leaf rust.

SD98102 was developed from the cross '2076-W12-11/Karl 92//NE89526'. This line has very good yield performance, good milling, and average baking quality attributes. SD98102 is moderately resistant to stem rust and moderately susceptible to leaf rust and WSMV. A third line (SD97059-2) is being increased for Foundation Seed with potential release in 2007. SD97059-2 was developed from the cross ND8889/NE90574. SD97059-2 had very good yield performance over the last 3 years; excellent resistance to stem, leaf, and stripe rusts; good resistance to scab; strong straw; and good milling and baking quality. This line will be targeted as a replacement to Arapahoe wheat across South Dakota.

Research. Our research continues to focus on line development, characterization, and applied studies in areas with potential to contribute to variety release. Crossing and germ plasm enhancement efforts continue to address high yield potential, end-use quality, and important biotic and abiotic constraints facing producers in South Dakota and the Northern Great Plains.

Basic research support projects included: end-use quality enhancements and inheritance and mapping studies on resistance to Fusarium head blight, stem rust, and freeze survival.

Eight hundred and forty lines have been screened in our mist-irrigated nursery in 2005 including the Northern Regional Performance Nursery (NRPN), Regional Germplasm Observation Nursery (RGON), and Southern Regional Performance Nursery (SRPN), in addition to South Dakota Crop Performance Trials (CPT), Advanced Yield Trial (AYT), Preliminary Yield Trials (PYT), and Early Yield Trial (EYT). Expedition hard red winter wheat, released by our program in 2002 showed better resistance to FHB than Wesley and Jagalene in producers' fields in eastern and central South Dakota in 2005. Two experimental lines, SD98102 and SD97059-2, have been increased with intention to release in 2006 and 2007, respectively. Both lines have good FHB resistance in addition to excellent leaf and stem rust resistance. They also had good performance and stability in the NRPN which is essential for adaptation in the northern Great Plains. Seven lines with promising FHB resistance were included in the 2006 AYT, 16 in the 2006 PYT, and 58 in the 2006 EYT. Our program relied on indigenous local resistance in the past. However, with the spread of FHB epidemics in winter wheat in South Dakota, use of highly resistant sources became paramount. In the 2005­06 season, we planted 151 out of 535 F3s and 134 out of 593 F2s with promising FHB resistance. Sixty-six of the F3s and eight of the F2s included resistance sources from Sumai 3, Ning7840, and their derivatives. About 7,000 head-rows with Sumai 3 type sources were planted in 2005. The best lines out of the head-row nursery will be included in the EYT in 2006. FHB-resistant advanced lines from these populations will be entered into regional nurseries to facilitate development of varieties with broad adaptation to the northern Great Plains.

A six parent diallel showed highly significant (P < 0.01) general combining ability in both greenhouse and field environments, but significant specific combining ability (P < 0.05) only in an F2 greenhouse environment for resistance to FHB. The ratio of combining ability variance components ranged from 0.66 to 0.89 indicating the importance of additive gene effects.

Cereal aphids, other arthropod pests, and arthropod-borne viral plant disease. [p. 186-187]

L. Hesler, W. Riedell, and S. Osborne (USDA-ARS-NGIRL, Brookings) and M. Langham and T. Cheesbrough (South Dakota State University).

Meaningful sources of plant resistance are needed against the bird cherry-oat aphid, a widespread pest of wheat. We found moderate levels of resistance to this aphid in several lines of triticale and low levels of resistance in two wheat cultivars. Transformed wheat lines did not manifest resistance to bird cherry-oat aphid. Three papers that summarize our results have been published, and another series of tests with triticale are nearly completed. Follow-up studies are underway to test for resistance to bird cherry-oat aphid in crosses between a widely planted wheat variety and a resistant triticale line.

Alteration of planting date is one potential method to limit infestations bird cherry-oat aphid, other cereal aphids, and various arthropods and reduce the incidence of some arthropod-borne viral plant diseases. We conducted a study in which winter wheat was planted over three dates (early, middle, and late; generally from late August to late September) to determine the effect on abundance of insect pests, incidence of plant damage, incidence of viral plant disease, and grain yield. The study was conducted simultaneously at two sites in South Dakota over three consecutive cropping seasons for a total of 6 site yrs. Cereal aphids were abundant in 3 site yrs. Bird cherry-oat aphid was the most abundant cereal aphid at the Brookings site, whereas greenbug predominated at Highmore. Aphid-days were greater in early versus late plantings. Aphid abundance in middle plantings depended on aphid species and site, but usually did not differ from that in early plantings. Incidence of Barley yellow dwarf virus (BYDV) declined with later planting and was correlated with autumnal abundance of cereal aphids. Incidence of BYDV ranged from 24 to 81% among 1999 plantings, and was less than 8% in other years. Damage to seedling wheat by chewing insects varied for two site-years, with greater incidence in early and middle plantings. Wheat streak mosaic virus, spring infestations of cereal aphids, wheat stem maggot, and grasshoppers were insignificant. Yield at Brookings was negatively correlated with BYDV incidence but not cereal-aphid abundance, whereas yield at Highmore was negatively correlated with aphid abundance but not BYDV incidence. Planting on September 20 or later reduced damage from chewing insects, and reduced cereal aphid infestations and resulting BYDV incidence.

The role of spring wheat in crop rotations. [p. 187-188]

Howard J. Woodard, Anthony Bly, and Brian Pavel.

Field plots (30' x 30') were established at a site near Brookings for planting corn/soybean, spring wheat/soybean and corn/soybean/spring wheat. No-till and Conventional tillage blocks were established for each crop rotation. Residue management plots were included in the plot design for each crop rotation and tillage system as either completely removing all loose residues (residue removal) or leaving the residues in place (residue maintenance). In the residue removal plots all of the loose residues across the whole plot were removed. The plot design is a strip-split-split randomized complete block with four replications. Briggs HRSW was seeded at 1.2 x 10^6^ pure live seeds/acre. Adequate levels of N and Cl was broadcast applied to the wheat plots. Weeds were controlled with appropriate herbicides.

No single source of variation significantly influencing grain yield, protein, or residue weight (Table 1). The only significant SOV interaction was tillage-rotation-residue for grain protein and possibly explained with ANOVA of protein by residue maintenance. ANOVA by tillage system showed a significant response for no-till residue weight. Treatment plots with residue maintained had significantly higher residue weights and probably a result of undecayed plant residues from prior years which were evidently seen in the residue samples. This difference was not measured or seen with conventional tillage since residues from prior crops were incorporated with tillage. ANOVA by residue maintenance showed a significant difference in grain protein between tillage systems when residues were maintained. Conventional tillage had significantly higher grain protein and probably a result of more available N from mineralization caused by tillage. Spring wheat grain yields were very good.

Publications. [p. 188]

• Hesler LS, Riedell WE, Langham MAC, and Osborne SL. 2005. Insect infestations, incidence of viral plant diseases, and yield of winter wheat in relation to planting date in the northern Great Plains. J Econ Entomol 98:2020-2027.
• Hesler LS and Tharp CI. 2005. Antibiosis and antixenosis to Rhopalosiphum padi among triticale accessions. Euphytica 143:153-160.
• Hesler LS, Li Z, Cheesbrough TM, and Riedell WE. 2005. Population growth of Rhopalosiphum padi on conventional and transgenic wheat. J Entomol Sci 40:186-196.
• Hesler LS. 2005. Resistance to Rhopalosiphum padi (Homoptera: Aphididae) in three triticale accessions. J Econ Entomol 98:603-611.