Ruben M. Gapasin, Maria Victoria L Judnl, Clarenda P. Pile, Evelyn B. Gergon,
Victor P. Gapud, and Santiago R. Obien
Visayas State College of Agriculture (VISCA), Philippine Rice Research Institute
doi.org/10.57043/transnastphl.1998.5882
Abstract
Studies were conducted to detennine alternative management strategies against the rice root-knot nematode, Meloidogyne graminicola in a rice-onion system. The cannister experiment, which was conducted to determine the effective soil depth level reached by rice hull burning (RHB) on nematode mortality, showed that nematodes were killed by heat even at 15 em depth. Several galls in the roots were counted in rice seedlings in the unburned treatments as compared to zero galls in all the burned treatments (0, 5, 10, 15 em depth). The field experiment using RHB significantly affected the number of galls and in most cases the nematode densities in the soi I and roots. Yield of onion increased almost three-fold in the burned treatment. The pot experiment showed that Tagetes sp. and two Crotalaria species reduced the number of galls and nematode densities in the soil by 73-96% and increased fresh root weight when incorporated in the soil. Rice hull burning and the use of Tagetes and Crotalaria could be effective alternative management strategies for M. graminicola in a rice-onion system.