Items from the United States - South Dakota.




Plant Science Department, Brookings, SD 57007 U.S.A.


A.M.H. Ibrahim, S.A. Kalsbeck, R.S. Little, S. Malla, Howard J. Woodard, Anthony Bly, Ron Gelderman, Jim Gerwing, Dwayne Winther, and Brian Pavel (South Dakota State University); and L. Hesler, W. Riedell, and S. Osborne (USDA-ARS-NGIRL).

Personnel changes. [p. 230]

Dr. Jeff Stein joined the faculty of the Plant Science Department as the small grains pathologist and assistant professor of plant science in September 2004. He received his B.S. degree in botany and plant pathology (1997) and Ph.D. degree in plant pathology (2002) from Michigan State University in East Lansing. He was a postdoctoral research associate at the Texas Agricultural Experiment Station in Bushland from 2002-04 where he conducted research on the survival and QPCR-based quantification of T. indica teliospores in soil. Dr. Stein directs a research program that focuses on the fungal diseases of small grains. His current research interests include the epidemiology of Fusarium head blight, common root rot, and tan spot. Dr. Stein is also an instructor for two courses in plant pathology at SDSU.


Winter wheat breeding and genetics.. [p. 230-231]

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

Crop report and testing sites. Winter wheat production in 2004 was estimated at 56.25 x 10^6^ bushels, down 9 % from last year. Grain yield averaged 45 bu/acre, which is two bushels above last year and is the second highest in the state's history. Producers harvested 1.25 x 10^6^ bushels from 1.65 acres, down 13 % from 2003.

In 2004, the winter wheat breeding program conducted testing 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 an additional nine sites west of the Missouri River in coöperation with John Rickertsen and Bruce Swan (SDSU West River Agricultural Research and Extension Center, Rapid City).

Autumn stand establishment at most testing locations was below average. After a very dry, mild winter, the crop was rated at 58 % poor to very poor by the State Statistics Report. The Kennebec site in Lyman Co. was lost due to high winds that covered the nursery with drifting soil. Dry conditions early in the growing season significantly pushed winter wheat flowering ahead of the 5-year average. However, 6 weeks of cool wet weather in May and June significantly extended the grain-filling duration ahead of the 5-year average in eastern parts of the state, resulting in record yield in some of these areas.

Research. Our research continues to focus on line development, characterization, and applied studies in areas with potential to contribute to cultivar 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 include end-use quality enhancements and inheritance studies on resistance to FHB, stem rust, and freeze survival.

In 2004, we screened 1,498 genotypes in a FHB mist-irrigated field nursery. The percentage of the South Dakota experimental lines that were superior to the FHB resistant check Expedition (disease index (incidence % * severity%/100) = 16.8 %) was 14.6 %. Advanced lines also were evaluated in the greenhouse using needle inoculation and were screened for the 3BS QTL associated with the Sumai 3-type resistance. Six genotypes, consisting of susceptible winter wheat Nekota and 2137, moderately susceptible winter wheat Harding, moderately resistant spring wheats ND2710 and BacUp, and resistant spring wheat Ning7840, were crossed in a partial diallel mating design to determine combining ability of FHB resistance. F1 crosses were evaluated in the greenhouse, and F2 crosses were screened under both greenhouse and mist-irrigated field conditions. One parent, Nekota, was excluded from the diallel mating design in the field condition because of few F2 seed and poor plant stand. In the greenhouse, both F1 and F2 were artificially point inoculated at anthesis, whereas F2 crosses in field conditions were artificially inoculated by a combination of corn-spawn spread at jointing stage and inoculum-suspension spray at anthesis. Disease index percentage of the crosses was analyzed using Griffing's method 4 and model 1. General combining ability was highly significant (P < 0.01) in both greenhouse and field conditions, but specific combining ability was significant (P < 0.05) only in F2 crosses grown in the greenhouse. The results showed that both additive and nonadditive gene effects are involved in the inheritance of FHB resistance.

We crossed several novel/under-utilized, broad-spectrum, stem rust-resistance genes into selected adapted lines. The F2 seed were planted in the greenhouse in February 2005. Our objective is to search for molecular markers linked to some of these genes in collaboration with Dr. Yang Yen, SDSU Molecular Microbiologist, and Dr. Jeff Stein, small grains pathologist.

New release. Wendy, the first HWWW from South Dakota, was released to seed producers for planting in 2004. Wendy is an early maturing line that combines good noodle quality, excellent winter survival, and high yield potential.

Foundation seed increase. One line (SD97W609) is being increased for Foundation Seed with 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. Wendy has excellent baking quality in predictive testing and in large-scale testing in the 2005 Wheat Quality Council. The cultivar has a high test weight, intermediate levels of polyphenoloxidase enzyme, average protein, very short coleoptile, and good sprouting resistance. Wendy is moderately resistant to stem rust and WSMV and is moderately susceptible to leaf rust.


Cereal aphids. [p. 231-232]

L. Hesler, W. Riedell, and S. Osborne (USDA-ARS-NGIRL, Brookings).

In collaboration with scientists at the USDA-ARS research laboratory in Stillwater and at Oklahoma State University, the performance and impact of rice root aphids, Rhopalosiphum rufiabdominalis, on various cereal and grass hosts was determined. Rice root aphids infest small grains throughout North America. For instance, we examined winter wheat fields in central South Dakota that were heavily infested with cereal aphids in the autumn of 1997 and 1999, and rice root aphids were the predominant aphids in these fields. However, little is known about their alternate hosts, appropriate techniques for rearing rice root aphids or their impact on cereal production. Rice root aphids were obtained by collecting numerous individuals from a winter wheat field near Brookings, SD, in autumn 1999. A low-cost technique for large-scale rearing of rice root aphid was developed using a soil-based medium with cedar chips used to cover seeds of the host plant (Elbon rye). This approach, which requires minimal labor and no specialized equipment, was used to establish colonies at facilities in Brookings and Stillwater. Rice root aphids were then used in greenhouse tests to evaluate survival and reproduction on selected grasses and cultivated cereals. Elbon rye and Altai wild rye were determined to be the most suitable hosts from 15 candidates, based on reproductive rates and aphid survival. These cereals were followed by TAM 110 wheat, OK 91806 barley, and Okay oats. Rice and sorghum were poor hosts, and corn was a nonhost. Generally, grasses were inferior hosts for rice root aphids when compared with cultivated cereals.

In a second study with Oklahoma scientists, field abundance of the rice root aphid was studied over a 2-year period in central Oklahoma. Rice root aphid and other aphid species (corn leaf aphid, R. maidis; bird cherry-oat aphid, R. padi; and greenbug, S. graminum) colonized winter wheat in Oklahoma during the autumns of 2001 and 2002. During each of the 2 years, rice root aphids infested winter wheat soon after emergence and continued to increase in number on the autumn-seeded crop until mid December when populations peaked and then began to decline, so that by early January the aphids were difficult to find. Rice root aphid populations of 3.6 aphids/tiller at the end of a 60-day infestation period reduced forage yield of wheat, which can be a significant economic impact for winter wheat that is grazed by cattle. Grain yield was not significantly reduced. Additional studies are underway to determine the impact of controlled infestations of viruliferous and nonviruliferous rice root aphids on yield loss in wheat.


Publications. [p. 232]

  • Kindler SD, Hesler LS, Elliott NE, Shufran KS, and Springer TL. 2003. Cereal and grass hosts of the rice root aphid, Rhopalosiphum rufiabdominalis, and a description of an efficient greenhouse rearing technique. J Agric Urban Entomol 20:51-59.
  • Kindler SD, Hesler LS, Elliott NE, Royer T, and Giles K. 2004. Seasonal abundance of rice root aphid in wheat and effects on forage and grain yields. Southwest Entomol 29:245-252.


Crop nutrient influences on wheat production. [p. 232-233]

Howard J. Woodard, Anthony Bly, Ron Gelderman, Jim Gerwing, Dwayne Winther, and Brian Pavel.

Nitrogen timing influence on HRSW grain protein and yield. Soil test nitrate-N (0-24") of 45 lbs/acre in a field near Aurora, SD, determined that 80 lbs/acre N would be required to support a 50 bu/acre yield goal. A lower than recommended N application rate as ammonium nitrate was applied (50 lbs/acre) at planting to avoid over-applying the fertilizer N requirement so that treatment differences could be observed. A control and high N rate (100 lbs/acre) also was applied at planting. Briggs HRSW was no-till planted at 1.2 million pure live seeds/acre. The 50 lbs/acre N application was applied either on 7 April (planting), 7 May (tillering), 3 June (jointing), 9 June (boot), or 23 June (heading). Plots were harvested with a small plot combine on 19 August. Grain protein was measured with near infrared reflectance spectroscopy.

The greatest grain yield was obtained with a rate of 50 lbs/acre N fertilizer applied at planting. Because N was applied later in the growing season, yield was reduced. Grain protein was highest with N treatment representing the lowest grain yield. Typically, the highest yielding wheat has the lowest protein content except when an abundance of N is available. The high N rate (100 lbs N/acre) did not have the lowest grain protein. No grain yield increase was gained from the addition of 50 lbs N/acre resulting in a sufficient amount of N available for protein, which was similar to lower-yielding treatments. As N rate increased from 0 to 50 lbs N/acre, grain increased significantly from 47 and 62 bu/acre, respectively. Increasing the N rate to 100 lbs/acre N rate did not increase the grain yield (62.1 bu/acre). Grain protein increased from 13.3 % to 15.5 % as N timing applications progressed from the planting to the heading stage.

Influence of liquid and dry nitrogen fertilizer materials on grain protein and yield of HRSW. Briggs HRSW was seeded in 7-in rows at 1.2 x 10^6^ pure live seeds/acre on 7 April in a no-till field near Aurora, SD. Fertilizer N at a rate of 100 lbs N/acre as urea was broadcast applied on all plots after planting, which was recommended for a 50 bu/acre yield goal. Four different N treatments at a rate of 30 lbs N/acre were applied on 7 July at the pollination growth stage (Feekes' stage 10) and dry or liquid ammonium nitrate (AMN) or dry or liquid urea ammonium nitrate (UAN) along with a control (0 lbs N/a). The rate of application for both liquid fertilizer materials was 20 gal/a. The liquid UAN solution was a 1:1 blend with water. Rain was received 4 and 5 days after treatment application (0.75 and 0.88 inches, respectively); adequate time for the foliar treatment applications to be absorbed by plant foliage and enough rain to incorporate the dry fertilizer into the soil for root absorption. Grain was harvest from the plots with a small plot combine on August 19, 2004. Grain protein increased significantly by all treatments when compared to the check from 57- 62 bu/acre. Some orthogonal contrasts for grain yield were significant and indicated that yield was higher for the dry fertilizer materials and severely decreased by the AMN liquid treatment applied at pollination. The orthogonal contrasts for grain protein indicated that all treatments increased grain protein when compared to the control. Dry fertilizer materials performed just as well as liquid in increasing grain protein at the pollination growth stage if there is adequate rainfall following the application. This data would suggest that plant tissue absorbed N from foliar applications of liquid fertilizer material and was not being washed off and taken up by the roots, indicated by the equal performance of both the dry and liquid fertilizer materials in increasing grain protein.

Managing cultural practices for high spring wheat yields. A field near Brookings, SD, was chosen to evaluate the impact of five cultural practices on the yield of Briggs HRSW planted on 7 April: soil fertility with a sulfur comparison, split application of nitrogen, seeding rate, foliar fungicide, and a fungicide seed treatment. The five cultural practices were employed to compare with standard recommended methods for successful wheat production. A comparison of soil fertility was made between standard nutrient recommendations determined from soil test results for a 60 bu/acre yield goal and nutrient applications for 100 bu/acre yield goal. The split application of nitrogen was evaluated by splitting the N for the 100 bu/acre yield goal into three timings; planting, tillering, and boot growth stages. The standard seeding rate of 1.2 x 10^6^ pure live seeds (PLS)/acre was compared to 2.2 x 10^6^ PLS/acre. Applying 4 oz/acre Tilt at flag leaf and 4 oz/acre Folicur at heading was the treatment used for disease control. The fungicide seed treatment used was Raxil XT (0.16 oz/100 lbs seed). Tilt (4 oz/acre) and Folicur (4 oz/acre) were applied on 9 and 22 June, respectively. Plots were harvested with a small plot combine on 19 August, 2004. Grain protein was determined with standard NIR technique.

Orthogonal contrasts for the soil fertility treatment showed that grain test weight was significantly higher with the recommended treatments over the control and higher fertilizer levels. Grain protein and yield were higher for the maximum treatments. More nutrients were applied to the maximum treatments, so it was difficult to determine which nutrient increased grain yield. However, the influence of nitrogen probably had the greatest impact on grain yield increases, because the grain protein increased above the true check (12.4 %) and above the recommended rate (13.5 %). The true check and recommended treatment plots were nitrogen stressed as indicated by lower grain protein. Seeding rate significantly increased grain test weight and protein over the recommended seedling rate. Applying foliar fungicide increased yield by 7.5 bu/acre over the fungicide control treatment. The seed treatment did not significantly influence any of the dependent variables. The split N application significantly increased grain test weight and protein. A sulfur application (25 lbs/acre) significantly decreased grain protein and yield.

Crop rotation, tillage, and crop residue management influences on HRWS yields. Briggs HRSW was seeded at 1.2 x 10^6^ pure live seeds in tilled or no-till plots on 7 April. Straw was returned to the residue-maintenance plots and removed from the residue-removal plots on 26 August. Spring wheat and soybean grain proteins and soybean grain oil were measure by standard NIR techniques. Neither tillage, crop rotation, nor residue management influenced grain yield (61-68 bu/acre). However, residue removal increased the grain yield of wheat (71 bu/acre) planted in no-till compared to the residue-maintained plots (59 bu/acre), presumably because of increased temperature of the bare soil during emergence and early season growth.