Growth response of three vegetables to smooth- and crenate-tailed females of three species of pratylenchus.

The effect of morphological variants of females of Pratylenchus penetrans, P. neglectus, and P. crenatus on the growth of three vegetables was studied. Variants were characterized by having either a smooth or crenate tail terminus. Pea was inoculated with variants of P. penetrans, one female per seedling, and grown at light intensities ranging from 1,350 to 21,600 lux in a series of five experiments. Only crenate-tailed females of P. penetrans suppressed the growth of pea and only when pea was grown at 3,900 lux. Radish was inoculated with morphological variants of P. penetrans, P. neglectus, and P. crenatus, four females per seedling, and grown at 3,900 lux in two experiments. Again, truly creuate-tailed females of P. penetrans inhibited growth. The two variants of P. penetrans had a similar infectivity, greater than that of the other two species of Pratylenchus. Only crenate-tailed P. penetrans reproduced on radish. Onion was inoculated with variants of P. penetrans and P. crenatus, four females per seedling, and grown at 14 C at 12,900 lux. Again, only crenate-tailed P. penetrans inhibited growth. The variants of P. penetrans had a similar infectivity, greater than that of P. crenatus. Neither species reproduced on onion at low temperatures.