Effect of Steinernema feltiae-Xenorhabdus bovienii insect pathogen complex on Meloidogyne javanica

Isolates of Steinernema feltiae MG-14 from Hawaii and SN from France, and the symbiont Xenorhabdus bovienii from each nematode isolate, were tested for their glasshouse efficacy against the root-knot nematode, Meloidogyne javanica, on several vegetable plants. Steinernema feltiae application for 3-5 consecutive days at rates of 1000 or 10000 infective juveniles (IJ) did not affect M. javanica root penetration and development in glasshouse pot experiments. IJ were recovered from the cortical tissue of tomatoes, soybeans, snow peas and cow peas. Xenorhabdus bovienii applied at 10¹⁰ colony-forming units (CFU) ml^-1 reduced root-knot nematode penetration in cow peas but was ineffective in tomato or snow pea. Xenorhabdus bovienii metabolites had no effect on M. javanica root penetration and egg production in soybean. Soybean plant growth was unaffected by nematode and bacterial treatment; biomass was lower in M. javanica-infected soybean, irrespective of treatment, than in non-infected soybean, but the differences between the treatments were non-significant. Accordingly, the Steinernema feltiae-Xenorhabdus bovienii complex did not meet the objective for the suppression of M. javanica root penetration and development.