Alan Sundermeier, Extension Agriculture and Natural Resources Agent
Beck Brothers, Henry County Producers
Study the changes in soybean cyst nematode levels during crop rotation.
|Soil type:||Millgrove loam|
|Crops:||1995 - soybean; 1996 - corn; 1997 - corn; 1998 - resistant soybeans|
In 1995, four soybean-cyst-nematode-resistant varieties (Asgrow 3134, Asgrow 3431, AgriPro 3460, Callahan 3377) and two susceptible varieties (Resnick, Asgrow 3237) were replicated three times and randomly planted into a nematode-infested field. Individual plots were 15' by 500'. Soil samples for cyst nematode egg counts were randomly collected at four-inch depths in each plot. Samples were taken in June and September each year. Corn was planted in the entire study area in 1996 and 1997 and cyst nematode resistant soybeans in 1998.
|Average Number of Cyst Nematode Eggs/200 cc Soil|
|June 95||Sept 95||June 96||Sept 96||June 97||Sept 97||June 98||Sept 98|
|Asgrow 3134 (R)||2880||213||1427||373||1120||120||0||67|
|AgriPro 3460 (R)||3827||667||1467||1053||773||120||200||93|
|Asgrow 3431 (R)||2840||1840||1760||680||867||93||373||107|
|Callahan 3377 (R)||2560||533||1067||307||800||107||53||40|
|Asgrow 3237 (S)||3280||7840||3200||1613||813||427||360||93|
|LSD (P = 0.05)||1521||2161||1568||1065||374||145||277||57|
One year of corn following susceptible soybeans did not lower cyst counts (2,227 eggs/200cc soil) to safe levels compared to one year of corn following resistant soybeans, which reduced cyst levels to 603 eggs/200 cc soil. Two years of corn were needed to lower soybean-cyst-nematode egg counts (below 500 eggs/200cc soil) to safe levels. In 1998 resistant soybeans did not allow cyst counts to increase.
This study confirms soybean-cyst-nematode control recommendations. After nematode infection is confirmed when planting susceptible SCN soybean varieties, plant two years of corn followed by one year of SCN resistant soybeans. Then, with counts below 500 eggs/200 cc soil, farmers may again use susceptible SCN soybeans in rotation.
For additional information, contact:
Ohio State University Extension, Henry County
104 E. Washington
St., Suite 107
Napoleon, OH 43545