The response of soybean genotypes to root-knot nematode Meloidogyne incognita in southern Vietnam

The southern root-knot nematode, Meloidogyne incognita (Kofoid et White, 1991) Chitwood 1949, is aserious pathogen of plants worldwide. In Vietnam, scientific information of root-knot nematode on soybean islimited. In this circumstance, our study aims to evaluate the reaction of twelve soybean genotypes to this soil-born pathogen. Root-knot nematode isolates were collected from soybean fields at difference geographic areas in Southern Vietnam. Intraspecies morphology and virulence variability of these isolates were determined on susceptible soybean cultivar Nam Vang. Thus, twelve soybean genotypes (Glycine max (L.) Merrill) were evaluated for the tolerance to a virulent isolate of root-knot nematode (Mi-PN-03) under net house conditions. Inoculation of 1000 J2s per plant did not effect on the growth of the twelve soybean genotypes after 8 weeks inoculating. Among the soybean genotypes tested, DN08 showed moderate level of resistance while others genotypes ranked in the range of susceptible or moderately susceptible levels. The results suggest that DN08 genotype could be applied to breeding program to develop new soybean cultivars that could be resistant to root-knot nematode.