Geographical variations in morphobiomatrics of reniform nematode, Rotylenchulus reniformis

Altogether six geographical isolates of Roty lenchulus reniformis collected from Andhra Pradesh, Delhi, Gujarat and Manipur were used for studying the morphological and biometrical variations in different developmental stages. Most of the characters in different isolates exhibited variability. The re-evaluation of the characters showed body length, distance from head to vulva, V% and stylet length to be highly stable. Excepting V% and to some extent 0% none of the allometric characters was found to be valid and justified. Lip region and tail shape of immature females and males, body shape and terminal projection of mature females were found to be highly variable in all the isolates. Inter-isolate comparisons revealed significant differences in body length, body width, position of dorsal oesophageal gland orifice, distance from head to median bulb and excretory pore and length of hyaline part of tail. Based upon this, Andhra Pradesh grape isolate was found to be a distinct morphological variant among the six geographical isolates studied in this investigation. A rare phenomenon of ovovivipary was evident in Gujarat isolate.