PATHOGENICITY AND REPRODUCTION OF MELOIDOGYNE-ARENARIA RACE-1 AND RACE-2 AND MELOIDOGYNE-INCOGNITA RACE-3 ON SOYBEAN

Pathogenicity and reproduction of three South Carolina populations of Meloidogyne arenaria race 2 (designated Florence, Govan, and Pelion), a Florida population of M. arenaria race 1, and a South Carolina popul ation of M. incognita race 3 were compared in greenhouse experiments o n the soybean cultivars Centennial, Coker 6738, Coker 6847, Kirby, and Perrin. In one experiment, all race 2 populations of M. arenaria prod uced more galls, egg masses, and eggs per gram of fresh root than the race 1 population on all cultivars. The Florence and Govan populations exhibited greater reproduction than the Pelion population on Centenni al, Coker 6738, and Kirby, and the Florence population had greater rep roduction than the Govan population on Perrin. In another experiment, a series of six inoculum densities between 500 and 20 000 eggs per pla nt were used. At most inoculum levels, the Florence population of M. a renaria race 2 had nearly 10-fold greater reproduction on 'Davis' soyb ean than either M. arenaria race 1 or M. incognita race 3.