Divergência genética e importância de caracteres em genótipos de batata-doce visando a produção de silagem

Abstract

RESUMOAtentando-se à necessidade de adoção de sistemas agrícolas mais sustentáveis, é importante que os programas de melhoramento de batata-doce procurem aumentar além da produtividade de raízes a produtividade e a qualidade de ramas para a produção de silagem. Objetivou-se avaliar a divergência genética e a importância de caracteres associados à produção e qualidade de silagem de ramas em genótipos batata doce. O experimento foi conduzido no Campus JK da Universidade Federal dos Vales do Jequitinhonha e Mucuri no delineamento experimental em blocos casualizados, com 12 tratamentos e quatro repetições. Foram avaliadas doze características de ramas e silagem. Verificou-se variabilidade genética entre os genótipos, sendo possível a seleção de genitores divergentes para futuros programas de melhoramento para produção de silagem. Os genótipos BD-54 e BD-31TO foram os mais divergentes em relação aos demais, sendo indicada a sua utilização em cruzamentos visando o melhoramento da cultura para silagem, uma vez que o elevado desempenho per se de todos os genótipos avaliados já foi verificado em trabalhos anteriores. As características Na, NDT e FDN foram aquelas que mais contribuíram para a divergência. Palavras-chave: alimentação animal, análise multivariada, Ipomoea batatas, melhoramento genéticoGenetic diversity and importance of traits in sweet potato genotypes aiming at silage production ABSTRACTIn view of the need for the adoption of more sustainable agricultural systems, it is important that the breeding programs for sweet potato seek to increase, besides the productivity of roots, the productivity and quality of vines for silage making. The objective of this study was to evaluate the genetic diversity and the importance of traits related to production and quality the of silage of vines of sweet potato genotypes. The experiment was conducted on the JK Campus of the Federal University of Vales do Jequitinhonha e Mucuri, in a randomized-block design with 12 treatments and four replicates. Twelve traits of vines and silage were evaluated. Genetic variability was detected among the genotypes, allowing for the selection of divergent genotypes for future breeding programs for silage production. Genotypes BD-54 and BD-31TO were the most divergent, and so they are indicated for use in crosses aiming at the breeding of this crop for silage-making, given that the high performance per se of all evaluated genotypes has already been verified in previous studies. The Na, TDN, and NDF traits were those that most contributed to divergence.

Genetic dissimilarity and relative importance of characteristics in banana cultivars through multivariate analysis

“…Among the advantages of using multivariate analysis techniques, we highlight the possibility of evaluating the importance of each characteristic studied in the estimation of dissimilarity (Azevedo et al, 2015). Thus, based on the criterion proposed by Singh (1981), in terms of relative contribution, it was evidenced greater importance for the characteristics of the vitamin A content, starch content, total soluble sugars, nonreducing sugars, antioxidant potential, pulp fresh mass, plant height and fresh fruit mass.…”

“…Brandão et al (2013) found that the elimination of some descriptors, such as fruit diameter, leaf blade length, petiole length and pseudostem diameter, used to characterize the banana germplasm, did not cause loss of information for the formation of the groups formed in 77 banana tree accesses evaluated. According to Brandão et al (2013) and Azevedo et al (2015), the analysis of less important characteristics for the study of divergence is not necessary in future studies, which reduces labor costs, cost of analysis and time. Table 4.…”

“…Methods such as the hierarchical UPGMA, Tocher optimization and techniques of graphic dispersion by canonical variables are also useful, since they allow the grouping of cultivars (Azevedo et al, 2015).…”

“…Although the evaluation of a greater number of characteristics makes possible a more complete study of the dissimilarity, the evaluation of many characteristics can be infeasible when the number of cultivars is large, being necessary to know the most important ones (Azevedo et al, 2015). Thus, the objective of this study was to study genetic dissimilarity among 15 banana cultivars by multivariate analysis and to determine the relative importance of the characteristics evaluated in this study.…”

Genetic divergence based on leaf vegetative and anatomical traits of Coffea canephora clones

“…Hybrids 12 and 15 were grouped within the maximum classification reference because they presented higher values for the evaluated vegetative and anatomical traits (Figure 1), being also classified into different groups by the Tocher method (Table 5 Notably, studies have pointed out the importance of using different methodologies to evaluate genetic variability aiming to ensure higher reliability of results (Azevedo et al, 2013(Azevedo et al, , 2015 and consistency in the clustering pattern (Nascimento et al, 2014). In fact, this criterion has been observed in studies aimed at characterizing the genetic variability among coffee genotypes to select superior materials for desired traits Notably, studies have pointed out the importance of using different methodologies to evaluate genetic variability aiming to ensure higher reliability of results (Azevedo et al, 2013(Azevedo et al, , 2015 and consistency in the clustering pattern (Nascimento et al, 2014). In fact, this criterion has been observed in studies aimed at characterizing the genetic variability among coffee genotypes to select superior materials for desired traits (Covre et al, 2016;W.…”