STUDIES ON THE INFECTION OF MELOIDOGYNE SPP WITH ISOLATES OF PASTEURIA

Abstract

Juveniles of Meloidogyne incognita and M. graminicola were encumbered with spores of three isolates of Pasteuria penetrans and the subsequent infection of these nematodes at 20, 25, 30 and 35ºC was recorded on tomato and Echinochloa colonum. An isolate from South Africa was the most pathogenic. Temperature affected pathogenicity and influenced the parasitic life cycle which is shorter at 30 and 35ºC than at 20 and 25ºC. Spore burdens of 11 per juvenile decreased the invasion potential of M. incognita, M. javanica and M. graminicola. When tomato plants were inoculated with M. incognita in soil containing different concentration of P. penetrans spores the numbers of female that produced egg masses were decreased. There were 66% fewer egg masses in pots treated with 9000 spores per g soil than in the controls.