Diversidade genética de populações naturais de mangabeira (Hancornia speciosa Gomes) no estado de Pernambuco por meio de marcadores moleculares

Abstract

The Mangabeira ( Hancornia speciosa Gomes) is a native fruit tree from Brazil, occurring in greater abundance in coastal and coastal plains of the Northeast region . Its fruits are widely consumed in natura or processed as juices, ice creams and jellies. Currently the genetic diversity of the species is largely threatened due to reduction of its original area of occurrence, deforestation , land speculation and planting crops such as sugar cane, coconut and pastures. Thus, the species is one of the most endangered fruit plants in the brazilian northeast . The objective of this study was to evaluate the genetic diversity of 38 H. speciosa genotypes from three populations of Pernambuco State through ISSR molecular markers . Leaves were collected in regions of Tamandaré Itamaracá , Nazaré and Paiva. We performed population structure analysis, Principal Coordinate Analysis, and a UPGMA dendrogram with all genotypes. Number of polymorphic loci number of monomorphic loci, Nei's genetic diversity, total heterozygosity , mean heterozygosity within groups , mean coefficient of differentiation between groups and number of migrants per generation were also calculated . Six ISSR primers were selected and produced a total 93 loci, 10 monomorphic and 83 polymorphic . The average number of polymorphic bands per primer was 11.5 , where UBC primer # 851 was the most polymorphic , with 14 bands . By cross checking between the UPGMA clustering , PCoA and structure of population, Hancornia 56 , 57 and Hancornia Hancornia 58 subjects showed a close relationship between them . The results showed a high level of genetic diversity within species ( He = 0.30 ), and found that most of the genetic variability found within a population . The gene flow was 1.18 , confirming information that tropical tree species have shown values of Nm greater than 1. Hancornia speciosa populations studied showed high levels of genetic diversity , most of which lies within populations .