Variation in the response of curcubits to Meloidogyne incognita and M. java']javanica

The responses of diverse cucurbit accessions, including cucumber, melon, watermelon, pumpkin, and Momordica spp., to Meloidogyne javanica and M. incognita, were evaluated. For melons and cucumbers, severity of galling was significantly affected by nematode species, but no significant effects of cultivars or cultivar x nematode species interactions on the level of galling were observed. Severity of galling was always higher for M. incognita than for M. javanica in any cultivar tested. Galling indices in melons were 0.3 and 1.6, and in cucumber 2.8 and 3.7, for M. javanica and M. incognita, respectively. Watermelon did not did show root galling when inoculated with M. javanica and showed a very low index (0-0.3) with M. incognita. Cucurbita accessions evaluated were the most susceptible. Galling index in pumpkin inoculated with M. javanica was significantly lower than that caused by M. incognita. Cucurbita moschata and the intraspecific hybrids of C. moschata were more resistant than commercial cultivars of melon, cucumber, and watermelon used as susceptible controls. Two Momordica charantia accessions out of 12 tested exhibited no or very low root galling in response to M. incognita and M. javanica. These findings indicate high resistance but not immunity to the nematodes.