REPRODUCTIVE ECOLOGY, GENETIC DIVERSITY AND MATING SYSTEM OF Copernicia prunifera (ARECACEAE)
Carnauba, Reproductive phenology, Reproductive structures, ISSR, Outcrossing rate
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. In relation to the characterization of reproductive structures, pollen viability and reproductive phenology of C. prunifera, observed that the inflorescences are made up of multiple flowers hermaphroditic, with light 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%. Additionally, 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 C. 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 what-if analysis for detection of genetic bottleneck, IAM models (infinite alleles) and SMM (steps of mutations), all subjects presented population reduction, in addition to deficit of heterozygosity (P < 0.0001). Outcrossing rates in population level (n = 247) pointed cross multiloco (tm) of 0.878 and between unrelated individuals (ts) of 0.738, indicating that the C. prunifera is a species of mixed-mating system, and preferentially alogama. The difference between the direct and multiloco crossing (tm-ts) has been reduced, indicating low outcrossing between closely related individuals. The average coefficient of endogamy (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 C. prunifera.