Morphological Comparisons of Host Races 1 and 2 of Meloidogyne arenaria from Florida.

Morphometric comparisons of two populations each of Races 1 and 2 of Meloidogyne arenaria from tobacco, peanut, and soybean in different localities in Florida showed no significant differences in any characters measured by light microscopy. Thirteen morphometric characters of females, 22 of males, and 21 of infective second-stage juveniles were measured for each population. The stylet length in each population and in each life stage was the least variable character. Proposed character additions to supplement the description of M. arenaria and more precisely define the species include the following: female - metacorpus length and width, metacorpus valve length and width, vulva-anus distance; male - length of stylet shaft and knobs, stylet base to head end; infective juvenile - length of stylet shaft and knobs, head end to metacorpus valve, excretory pore to head end, metacorpus valve length and width, and d-ratio.