Identifying cover crops as non-hosts for management of soybean cyst nematode, Heterodera glycines
Guiping Yan - North Dakota State University, Department of Plant Pathology. Krishna Acharya- North Dakota State University, Department of Plant Pathology
Soybean cyst nematode (Heterodera glycines) reproduces on a wide range of plants, including some cover crops. With the increasing acreage of cover crops planted in the Northern Great Plains for improving soil health, quality, and ecosystem, it is important to investigate whether these cover crops have an additional benefit for suppression and control of soybean cyst nematode (SCN), a major pest in soybean production. Forty-one cover crop species/cultivars from four plant families (Brassicaceae, Fabaceae, Linaceae, and Poaceae) were evaluated for their host status to SCN under controlled greenhouse conditions. Evaluation experiments were conducted in a walk-in growth chamber with two SCN populations, HG type 0 and HG type 7, from two soybean fields of North Dakota, using naturally infested soils and artificially inoculated sandy soils. After 35 days of growth, white SCN females were extracted from individual plants, and then identified and counted to determine a female index (FI) for each crop. Out of the 41 cover crops tested, SCN white females developed only in 10 crop species/cultivars, suggesting as either hosts (FI ? 10) or poor hosts (0 < FI < 10). The other 31 crop species/cultivars did not support any reproduction of both SCN populations across all the experiments and were classified as non-hosts (FI = 0). The non-host crops identified in this study can be planted as cover crops or rotational crops in SCN-infested soybean fields to reduce SCN numbers to manage this damaging disease.