|Stetina, Salliana - Sally|
Submitted to: Journal of Nematology
Publication Type: Abstract Only
Publication Acceptance Date: 5/1/2006
Publication Date: 6/1/2006
Citation: Chen, S., Wyse, D.L., Johnson, G.A., Porter, P.M., Haar, M.J., Stetina, S.R., Miller, D.R., Betts, K.J., Klossner, L.D. Effect of cover crops alfalfa, red clover, perennial ryegrass, and rye on soybean cyst nematode population and soybean and corn yields in minnesota.. Journal of Nematology. 38:267.
Technical Abstract: A field experiment was carried out to evaluate alfalfa (Medicago sativa), red clover (Trifolium pratense), perennial ryegrass (Lolium perenne), and rye (Secale cereale) as cover crops for their effects on soybean cyst nematode (SCN, Heterodera glycines), and soybean (Glycine max) and corn (Zea mays) yields in Waseca, Lamberton, and Rosemount, MN. Alfalfa, red clover, and perennial ryegrass were interseeded in soybean at 0 or 2 wks after planting soybean in 2002 and 2004, and killed with herbicide prior to planting corn in 2003 and 2005. Rye was planted after harvesting corn and killed in the following spring. SCN-resistant and susceptible soybean cultivars were planted in 2002 and SCN-susceptible soybean was planted in all plots in 2004. Nematode egg population densities were determined at planting, midseason, and harvest in the soybean years, and at planting and harvest in the corn years. As expected, SCN-susceptible soybean supported greater egg population density than SCN-resistant soybean. Reduction of egg population density by red clover and alfalfa was observed in some occasions, probably mainly due to reduced soybean growth, but the effects were inconsistent. Perennial ryegrass did not affect SCN in most cases. There was no effect of rye on egg population density. SCN-resistant soybean produced higher yield than susceptible soybean at all sites in 2002. Compared with susceptible cultivar, the resistant cultivar in 2002 increased yield of soybean in 2004 at Rosemount, but not at the other two sites. The cover crops interseeded with soybean not only reduced soybean yield but also lowered corn yield in the following years in most cases. The results suggest that red clover and alfalfa as cover crops may reduce nematode populations, but to avoid yield loss due to competition an even later planting date for the cover crops may be more appropriate for use in the soybean-corn rotation in Minnesota.