THE USE OF RAPD AMPLIFIED DNA AS MARKERS FOR VIRULENCE CHARACTERISTICS IN SOYBEAN CYST-NEMATODE

The feasibility was investigated for developing RAPD-based diagnostic dot blot tests to separate field isolates of soybean cyst nematode wit h different virulence to resistant cultivars of soybean. A RAPD primer was found that separated two northern Indiana isolates of the nematod e with similar virulence toward resistant soybean lines, from two sout hern Indiana isolates with different virulence characteristics; and a molecular marker probe was developed for use with dot blots. The study demonstrates the feasibility for developing a RAPD-based test for use in diagnosing larger groups of field isolates of nematodes that share common virulence characteristics toward resistant cultivars.