Biotechnological tools in guava (Psidium guajava) aiming the resistence to Meloidogyne enterolobii

Abstract

Guava is an important fruit crop in Brazil. The occurrence of Meloidogyne enterolobii, a polyphagous nematode and an important parasite in different crop species, is actually, the major problem of guava production in Brazil. The breeding programs of this species require achievement of resistant cultivars for this parasite or the achievement of resistant and compatible rootstocks with guava, main because was not reported at moment the presence of resistance to this nematode in guava specie. Some genotypes of yellow and red types of araçá (Psidium cattleyanum) were reported as resistant for this nematode, but this genotypes are not compatible as rootstock with commercial genotypes of guava. In the same way, the attempts of interspecifical controlled crosses between guava and araçá were not resulted in success. In this way, the use of biotechnological tools that aim the achievement of hybrid embryos between this two species can be an alternative for viable and accelerate the M. enterolobii resistance in breeding programs of guava. The aim of this project will be use different biotechnological tools as the controlled crosses with embryos rescue and in vitro cultivation, in vitro pollination and ovary culture and the achievement of self tetraploids in guava as a way to viable the hybrid plants, and also the works of micrografting of guava with araça. The uses of biotechnological tools could result in extension of knowledge about both species, as well as, viable the achievement of hybrids and its utilization as new cultivar, for accelerate conventional breeding of guava or in achievement of resistant and compatible rootstocks between the guava and the hybrids obtained. (AU)