Caracterización química foliar de los árboles de aguacate criollo (Persea americana var. drymifolia) en los bancos de germoplasma de Michoacán, México

Abstract

Persea americana var. drymifolia (mexican creole avocado) is used as rootstock in Hass avocado orchards and it is a source of genes for resistance to pests and pathogens for this and other cultivars. The Mexican varieties are being replaced by commercial cultivars or lost by the destruction of ecosystems. Therefore, we studied 250 avocado trees of 52 accessions from 14 Mexican states; 247 mexican creóle avocado and 3 hybrids ofthat tree with P. shiedeana, P. americana var. americana or P. americana var. guatemalensis, planted at germplasm banks, Michoacán. Foliar chemical composition was analyzed by GC-MS. High chemical variability among the trees was found with the 64 volatile compounds detected. Two large chemical groups on a scale of 100% dissimilarity and 22 groups at 10% dissimilarity were found by cluster analysis. The hybrids were grouped differently from the typical creóle trees and were also different in the altitude of origin. We corroborate that foliar volatiles serve as markers to differentiate creóle avocado trees and their hybrids and that much variation attributed to the creóle variety comes from hybridization in contact zones of this variety with other varieties or species of Persea.