Reaction of Psidium guineense and Psidium guajava genotypes to infection of Meloidogyne enterolobii

Abstract

Psidium guajava (guava) is an important crop and economic resource in many tropical countries and Brazil stands out as one of its major commercial producers. The guava crop has been severely attacked by the plant parasitic nematode Meloidogyne enterolobii which has caused drastic reduction of productivity and, in some cases, even total loss of cultivated areas. The use of resistant rootstocks that are tolerant to these soil pathogens can be a low-cost solution to this pathogen, which has established itself as one of the major constraints for the cultivation of guava in Northeast Brazil. The objective of this work was to evaluate the reaction of P. guajava and P. guineense to M. enterolobii infection under greenhouse conditions, with an infection period of 60 days. 12 P. guineense, and 4 P. guajava were evaluated. The host response to the nematode infection was evaluated according to the following parameters: gill index (GI), reproductive factor (RF), and reduction of reproductive factor (RRF). Considering the RRF criteria, the P. guineense genotypes, AR1, AR3, AR4 and AR10 were considered resistant. The RF index was considered inadequate to evaluate resistance in the 60 days period, due the slow development of the parasite in P.guineense.