Corn, 2006

William J. Wiebold is a Professor of Plant Sciences and State Extension Specialist; Howard L. Mason is a Senior Research Specialist; Delbert Knerr, Ri chard W. Hasty, David M. Schwab, and Scotty L. Smothers are Research Specialists; Travis Belt is a Research Associate in Plant Sciences and Bruce Burdick is the Superintendent of the Hundl ey-Whaley Research Center.Compares hybrids and includes experimental procedures, seed corn characteristics and seed corn company addresses

Soybean Cyst Nematode Reduces Soybean Yield Without Causing Obvious Aboveground Symptoms

Field experiments were conducted at locations in northern and southern Illinois, central Iowa, and central Missouri from 1997 to 1999 to investigate the effects of Heterodera glycines on soybean growth, development, and yield. A wide range of infestation levels was present at all locations. Two locally adapted cultivars, one resistant to H. glycines, were grown at each location. Cultivars were planted in alternating four-row strips with 76 cm between rows. For each cultivar, 20 1-m-long single-row plots were sampled every 2 weeks starting 4 weeks after planting. Infection by H. glycines reduced plant height and leaf and stem weight on the resistant cultivars in the first 12 weeks after planting, and delayed pod and seed development 12 to 14 weeks after planting. Biomass accumulation was not reduced on the susceptible cultivars until 10 weeks after planting; reduction in pod and seed development occurred throughout the reproductive stages. Susceptible cultivars produced significantly lower yields than resistant cultivars, but the yield reductions were not accompanied by visually detectable symptoms

Corn, 2005

William J. Wiebold is a Professor of Plant Sciences and State Extension Specialist; Howard L. Mason is a Senior Research Specialist; Delbert Knerr, Richard W. Hasty, Eddie G. Adams, David M. Schwab, and Scotty L. Smothers are Research Specialists; Travis Belt is a Research Associate in Plant Sciences and Bruce Burdick is the Superintendent of the Hundley-Whaley Research Center.Compares hybrids and includes experimental procedures, seed corn characteristics and seed corn company addresses