Comparação de eventos fenológicos e diversidade genética de Handroanthus serratifolius (Vahl) S.O.Grose (Bignoniaceae) em área urbana e rural

Abstract

Handroanthus serratifolius (Vahl) S. O. Grose (Bignoniaceae), known as yellow Ipe, is considered a symbol of Brazil, characteristic of dense and secondary rain forests, as well as of the plains of Latin America. In Brazil, its occurrence extends from the Amazon region to the southeast region. It plays an important economic role in providing wood, substances for the pharmaceutical industry, and for urbanization and landscaping projects. The indiscriminate exploitation of Ipe wood can lead to the significant loss of alleles, which can cause the extinction of its population. Phenological and genetic knowledge can assist in conservation programs for the species. This study aimed at analyzing and understanding the phenology and genetic traits of this species, such as its diversity and spatial genetic structure concerning individuals located in urban and rural areas. For this purpose, we used 96 individuals, located at two population sites within the municipalities of Lavras, Minas Gerais (MG), Brazil, and Itumirim (MG), considered urban and rural populations, respectively. Samples were randomly taken, using only those presenting reproductive event. For the genetic analyzes, nine ISSR primers generated 96 polymorphic bands. The results indicate low genetic diversity for individuals present in urban areas (He = 0.38) and rural areas (He = 0.40). The AMOVA showed that there is greater diversity within populations (93.3%). The spatial genetic structure indicated co-ancestry on both sites (P > 0.05), at distances of 600 and 900 m, in urban and rural areas, respectively. Phenology presented seasonality in relation to reproductive and vegetative phenophases. The events occurred in a synchronous manner, with precipitation factor being of greate influence. In the urban area, the occurrence of phenophases was more intense when compared to rural areas.