Plant parasitic and vector nematodes associated with Asiatic and Oriental hybrid lilies

A survey for distribution and abundance of plant parasitic nematodes in fields grown to Lilium in Himachal Pradesh, India at four study sites viz. Nagrota (at 810 m a.s.l.), Palampur (at 1270 m a.s.l.), Sunder Nagar (at 1400 m a.s.l.) and Chail (at 2250 m a.s.l.) was carried out. Moderate (101-500/200 ml soil) to high (501-1000/200 ml soil) populations of phytonematodes including the vectors for plant viruses (Aphelenchoides avenae, Criconemoides spp., Hoplolaimus spp., Longidorus spp., Paratylenchus spp., Pratylenchus spp., Rhabditis spp., Trichodorus spp., Tylenchoryhnchus spp., Tylenchulus spp. and Xiphinema diversicaudatum) were recorded. Mean population of nematodes was positively correlated with pH in all the study sites, negatively correlated with electrical conductivity (EC), percent organic matter (OM%), available potassium (K) and positively correlated with percent carbon (C%), available nitrogen (N) and available phosphorus (P) in all but one study site. The highest incidence of virus-vector nematodes viz. X. diversicaudatum, Longidorus spp. and Trichodorus spp. was recorded at Palampur. Only Strawberry latent ringspot nepovirus (SLRSV) was detected in Lilium cvs. Star Gazer Max and Galeili by Enzyme Linked Immunosorbent Assay (ELISA) and reverse transcription polymerase chain reaction (RT-PCR) and in X. diversicaudatum associated with the cultivars by RT-PCR. Cucumis sativus used as bait plants showed SLRSV symptoms after 15 days of nematode inoculation and further SLRSV was again detected by ELISA and RT-PCR in C. sativus plants confirming the transmission of SLRSV by X. diversicaudatum in Lilium.