Genetic divergence among castor bean lines and parental strains using ward's method based on morpho-agronomic descriptors/Divergencia genetica entre linhagens e parentais de mamoneira pelo metodo ward, baseada em descritores morfoagronomicos

This study sought to evaluate the genetic divergence among castor lines and parental strains in the germplasm bank at the Federal University of Reconcavo da Bahia (Universidade Federal do Reconcavo da Bahia) using morpho-agronomic descriptors. This experiment was conducted from 2014 to 2015 with 208 treatments represented by bank accessions that were analyzed using a randomized block design, which established homogeneity of the experimental conditions with all treatments repeated in four blocks. The genetic divergence analysis was performed using Ward's method and Tocher's method based on Gower's distance, which are two clustering methods used in studies with castor beans, with the help of the statistical programs R and GENES. The results revealed the formation of 21 groups for 13 morphoagronomic descriptors, six qualitative and seven quantitative, indicating the presence of variability in the bank. The groups containing promising accessions for the characteristics of agronomic interest, including precociousness, fruit dehiscence, and plant height and yield were 2, 7, 8, 10, 14, 15, 16, and 17, which suggested potential hybrid crosses. The descriptors with the greatest contribution to variance were yield, plant height, the number of seeds per raceme, flowering and seed weight per raceme. Keywords: Ricinus communis L., multivariate, variability. Este trabalho objetivou avaliar a divergencia genetica entre linhagens e parentais de mamoneira do Banco de germoplasma da Universidade Federal do Reconcavo da Bahia, por meio de descritores morfoagronomicos. O experimento foi conduzido no periodo de 2014 a 2015, com 208 tratamentos representados pelos acessos do Banco, avaliados no delineamento em blocos casualizados, estabelecendo a homogeneidade das condicoes experimentais com todos os tratamentos igualmente repetidos em quatro blocos. A analise de divergencia genetica foi realizada pelo metodo Ward e pelo o metodo de Tocher por meio da distancia de Gower, sendo esses metodos de agrupamento utilizados em estudos com mamoneira, com o auxilio dos programas estatisticos R e GENES. Os resultados revelam a formacao de 21 grupos para 13 descritores morfoagronomicos, sendo seis qualitativos e sete quantitativos, indicando a presenca de variabilidade no Banco. Os grupos que apresentam acessos promissores para as caracteristicas de interesse agronomico como precocidade, deiscencia dos frutos, estatura e produtividade, sao 2, 7, 8, 10, 14, 15, 16 e 17, sugerindo possiveis