Nuclear and chloroplast microsatellites reveal high genetic diversity and structure in Platonia insignis Mart., an endangered species native to the Brazilian Amazon

Low Diversity and High Genetic Structure for Platonia insignis Mart., an Endangered Fruit Tree Species

“…The genetic differences observed in the DAPC clusters, in the phylogenetic tree, and in the F ST pairwise matrix indicate that the Chapadinha location, which represents a sample from the Cerrado biome, is genetically distant from samples of the Amazon biome, which was also observed by Nascimento et al [24]. The correlation between genetic and geographic distances confirmed by the Mantel test, and the strong structure between the Amazon and the Cerrado biomes observed in this study and in Nascimento et al [24] make the isolation of populations by distance evident.…”

“…The groups formed in DAPC and the neighbor-joining tree are consistent with the sampled locations, and the little admixture observed indicates a high genetic differentiation among them. The fact that most of the genetic variation is concentrated among and not within locations (F ST = 0.68; p < 0.001) contradicts the studies published so far for P. insignis [20,22,24] and is not expected in the case of allogamous species. It is possible that our results are different because we evaluated very distant locations from different biomes, although a similar study [24] with SSR markers, also including locations from the Amazon and Cerrado biomes, detected that most of the variability was found within locations (72%), and within DAPC groups (78%).…”

“…The fact that most of the genetic variation is concentrated among and not within locations (F ST = 0.68; p < 0.001) contradicts the studies published so far for P. insignis [20,22,24] and is not expected in the case of allogamous species. It is possible that our results are different because we evaluated very distant locations from different biomes, although a similar study [24] with SSR markers, also including locations from the Amazon and Cerrado biomes, detected that most of the variability was found within locations (72%), and within DAPC groups (78%). Pontes et al [20] and Pena et al [22] used ISSR markers to characterize accessions collected in different locations of Pará, including Marajó Island, maintained in the Eastern Amazon BAG (Active Germplasm Bank) [12].…”

“…Paraense et al [23] developed 22 microsatellite markers (nSSRs) for bacurizeiro. Of these, eight nSSRs, in addition to three chloroplast microsatellites (cpSSRs), were used by Nascimento et al [24] to evaluate seven populations of the species, originating from two Brazilian biomes (Amazon and Cerrado). Such studies did not elucidate some aspects, such as loci under possible selection effects and the detection of large-scale variability, which can be better understood by population genomics.…”

Genetic divergence between Brazilian Northern and Northeastern populations of Spondias mombin revealed with SNP markers

“…A possible explanation is that this population was the only one sampled in the Cerrado biome, which may also have led to adaptations and differentiation through evolutionary processes of natural selection or genetic drift. The discrimination between Cerrado and Amazon populations of the fruit tree P. insignis based on eight nuclear (ncSSR) and three chloroplast (cpSSR) microsatellite markers was also observed byNascimento et al (2021), including the municipality of Chapadinha among the Cerrado populations.AMOVA showed that the greatest source of genetic variation is found among individuals within (61.4%) than among populations (38.6%), and within (59.3%) than among DAPC groups (40.7%). Higher intrapopulation than interpopulation genetic variation is expected in allogamous perennial species since most variation occurs between individuals within populations(Hamrick et al 1992;Paschoa et al 2018;Francisconi et al 2021).…”