Population structure of Agave gentryi B. Ullrich in southern Nuevo León

Abstract

Agave has great economic demand in Nuevo León; of the 14 species reported, Agave gentryi B. Ullrich has the highest rate of utilization for distillation of individuals in juvenile stages and in harvesting, so based on the hypothesis that the population of these stages has decreased, the objective of the research was to evaluate the population structure of the phenological stages of this species. The study area was located in the Ejido La Canoa, municipality of Aramberri. Sampling was carried out twice a year at two sampling sites: the first in a harvesting area and the second in an area excluded from harvesting. A total of 10 quadrats 64 m² were established, from which the individuals were counted, classified into phenological stages, and morphometrically evaluated. The data follow a normal distribution, so a factor analysis and a Tukey test were performed. The results indicate a total of 3 687 and 6 156 individuals per ha for the sites under harvesting and without harvesting, respectively; there is a highly significant difference in quadrat coverage (F=4.3, p # 0.01). In the non-harvested sites, the phenological stage corresponding to juvenile stage one registered the highest relative abundance with 36%, the adult stage presents relative dominance of 33.42%, and the juvenile stage two exhibits an importance value index of 50.48%; in contrast, in the harvested sites, the highest values correspond to the adult stage, relative abundance of 31.82%, relative dominance of 51.4%, and importance value index of 54.41%; a high demand was found in juvenile phenological stages one and three. Keywords:.