GENETIC DIVERSITY OF LINALOE IN TROPICAL DECIDUOUS FOREST POPULATIONS IN MEXICO

Abstract

Genetic diversity is important for the adaptation of a species to environmental changes, thus knowledge of the level and distribution of diversity is useful for developing conservation and management strategies for a species; however, information on genetic diversity is scarce for tree species that habit in the tropical deciduous forest as is case of linaloe [Bursera linanoe (La Llave) Rzed., Calderón & Medina], a species that grows in two biotic subprovinces in the dry tropical forest of the states of Guerrero, Morelos, Puebla and Oaxaca in Mexico. Therefore, the objective of this study was to estimate the genetic diversity and structure of Bursera linanoe in natural populations at two biotic subprovinces. In 2019, foliage was collected from 92 linaloe trees in four populations of the biotic subprovinces Balsasana and Cañadiana. Subsequently, the DNA was extracted from the foliage with the CTAB protocol. Five inter-microsatellites (ISSR) were used, and the fragments were separated on agarose gels. The following estimators of genetic diversity were calculated: percentage of polymorphic loci (P), expected heterozygosity (He), effective number of alleles per locus (Ne) and Shannon index (SI). In addition, the Wright’s F_ST was estimated, and an analysis of molecular variance (AMOVA) was performed. Also, the genetic structure was evaluated with the STRUCTURE software. The values of the genetic diversity estimators were P = 100 %, He = 0.352, Ne = 1.618 and SI = 0.522, the F_ST value was 0.160. The partition of genetic diversity was 74 % within populations, 21 % between populations and 5 % between subprovinces. Four groups (K) were formed with the linaloe trees of the four populations. The number of migrants was 1.3 per generation. High genetic diversity and high genetic differentiation between population of Bursera linanoe were found.