Morphological characterization of Amazon pepper accessions

In Brazil wide variability is found in peppers of Capsicum genus and the Amazon region is an important center of diversity. Information about the diversity in collection is useful, among other aspects, to increase the efficiency of breeding studies of cultivated species. The present study aimed to characterize the morphology and estimate the genetic diversity of 40 Capsicum accessions from Universidade Federal do Amazonas germplasm collection. Morphological descriptors recommended by IPGRI (International Plant Genetic Resources Institute), for the Capsicum and sensory analysis for pungency and flavor were used to characterize the accessions. Seventeen descriptors, identified as essentials, were used to calculate the genetic similarity among accessions, considering the general similarity coefficient of Gower. The hierarchical method of the average of the distances UPGMA (Unweighted Pair-Group Method using an Arithmetic Average) and PCO (Principal Coordinates Analysis) were used to cluster the accessions. Three species were found comprising 35 accessions of C. chinense, one of C. baccatum and four C. frutescens. Phenotypic variation among accessions was observed mainly on fruit characteristics that showed differences in size, shape, color and pungency. Several chilli peppers morphotypes were identified: two accessions of murupi; two lady's finger; four from "malagueta"; seven from fisheye; 13 from smell pepper, and 12 curabia. Cluster and dispersion graph analysis were concordant in clustering accessions with small genetic distance. The collection presents a wide variation among accessions.