Population dynamics of root-knot, spiral and stunt nematodes on sweetsop, annona squamosa [annonaceae] in relation to soil temperature

ABSTRACT

Twelve menatode genera were found in association with the rhizosphere of sweetsop. The nematodes recorded were Aphelenchus, Criconemoides, Diphtherophora, Ditylenchus, Helicotylenchus, Longidorus, Meloidogyne, Rotylenchulus, Trichodorus, Tylenchorhynchus, Tylenchus and Xiphinema. Of these, H. exallus, M. incognita and Tylenchorhynchus sp. were the most consistently encountered nematodes throughout the year. The population densities of these nematodes were found to have at least one distinguishable peak in August/September. These peaks were positively correlated with soil temperature range of 27-29C. However, the root populations of M. incognita reached its peaks in October and April, which negatively correlated with a moderate soil temperature [24]. This is the first report of nematodes associated with sweetsop Annona squamosa [Annonaceae] and its nematode population dynamics in Egypt