Morphometric variations in Meloidogyne javanica from West Bengal, India.

摘要

Morphometric observations on the different populations of M. javanica from West Bengal revealed that stylet length (14.84 to 16.83 micro m, mean 16 micro m), DGO, o, m, distance from head end to median bulb, length and width of metacarpus valve were considered to be least variable characters (CV<12) in female. Morphometrics of perineal patterns in M. javanica showed least variability in distance between anus to vulval slit and phasmid to vulva whereas length of vulval slit, distance from vulval slit to tail whorl and inter-phasmidial distance (CV<12) exhibited moderate variations. Variations in length, width and a-ratio of eggs were recorded the least. Evaluations of various characters in second stage juveniles of M. javanica based on 30 specimens indicated that styled length (12.87 to 14.85 micro m, 13.2 micro m) was the most stable character, however, distance from head end to oesophageal intestine junction and excretory pore, tail length, and body width, b, b1, c, c' and m were found to be moderately variable characters (CV<12) and therefore, can be considered as supplementary differentiating parameter for the species. Variations in tail terminus and hyaline tail areas were also observed in M. javanica but they were considered to be intra-specific variations.