Association of phytonematodes and their pathogenicity on Jasmine

A survey was conducted in Virudhunagar, Madurai, Dindugal, Tirunelveli and Salem districts of Tamil Nadu to know the association of plant-parasitic nematodes in jasmine (Jasminum spp.). Eight nematodes viz., Hoplolaimus indicus, Helicotylenchus dihystera, Longidorus sp., Meloidogyne incognita, Pratylenchus delattrei, Radopholus similis, Tylenchorhynchus nudus and Xiphinema insigni were found associated with rhizosphere of jasmine. Meloidogyne incognita and P. delattrei were the frequently encountered nematodes with higher relative density and prominence value. Experiments conducted on pathogenicity of M. incognita and P. delattrei on Jasminum sambac revealed that an inoculum level of 10,000 or more M. incognita J2/plant was pathogenic which caused significant reduction in plant height, shoot weight, root weight and flower yield. Reduction in growth and yield of jasmine due to M. incognita inoculation was higher than P. delattrei at equal inoculum levels.