COLLECTION AND EVALUATION OF GUAVA (PSIDIUM GUAJAVA L.) FOR NEMATODE RESISTANCE IN MALAYSIA

Abstract

Guava (Psidium guajava L.) belongs to the Myrtaceae family, which has more than 80 genera and 3,000 species distributed throughout the tropics and subtropics. Guava is one of the fruit types that were given priority for fruit cultivation in Malaysia. The germplasm collection was made to increase the available gene pool of guava in MARDI for ex situ conservation and breeding work especially to search for the resistance genes for root knot nematodes that might exist in the wild grown of guava. The collection was mainly done in the western part of Peninsular Malaysia and was planted commercially in the same region. The guava was collected as seed and grown in the form of seedling for inoculation and screening. A total of 195 accessions were collected and to date 68 accessions were screened for resistance to root knot nematode. Preliminary screening showed that 3 accessions displayed potential resistance and one accession was identified to be resistant to root knot. These accessions are graft-compatible with local commercial clones of guava and thus could be used as a rootstock or parent for guava improvement programmes against the root knot nematode.