Ecologia reprodutiva, diversidade genética e sistema reprodutivo de Copernicia prunifera (ARECACEAE)

Abstract

The present study aimed to describe the reproductive characteristics of the palm Copernicia prunifera, investigating the genetic diversity and the system of reproduction of a natural population by using ISSR markers in the state of Rio Grande do Norte, Brazil. Were observed multiple inflorescences, constituted of hermaphroditic flowers, with clear coloration. In addition, the flowers are composed of 3 sepals, 3 petals, 6 stamens and 3 carpels. The average percentage of viable pollen was 62%. There are differences in the reproductive phenophases between populations evaluated, being observed continuous activity in the production of flowers and ripe fruit in the population of Parnamirim, and discontinuous observation in the Macaíba population. The markers used to analyze the genetic diversity and reproductive system of Copernicia prunifera were usually informative and presented high polymorphism. The values of the indices of diversity among the adults and the progenies did not differ statistically (He = 0.319 and I = 0.470; He = 0.337 and I = 0.505), respectively. In the hypothesis test for detection of genetic bottleneck, IAM models (infinite alleles) and SMM (steps of mutations), observed occurrence of population reduction. Outcrossing rates in population level (n = 247) pointed multilocus outcrossing rate (tm) of 0.878 and single locus outcrossing rate (ts) of 0.738, indicating that the Copernicia prunifera is a species of mixed mating system, and preferentially alogamous. The mating among relatives rate (tm - ts) has been reduced, indicating low outcrossing between closely related individuals. The fixation index between seed tree (F) was negative (- 0.200), pointed to the absence of inbreeding. The correlation of selfing (rs) showed high value (0.914). The results found in this study generated information on the reproductive ecology of the specie, but also to adopt management strategies, conservation and genetic improvement of palm Copernicia prunifera.