Genetic divergence in sesame based on morphological and agronomic traits

Abstract

-The evaluation of diversity in germplasm collections is important for both plant breeders and germplasm curators to optimize the use of the variability available. Diversity can be estimated by different genetic markers. The purpose of this study was to estimate the genetic divergence of 30 morphological and agronomic traits in 108 sesame genotypes by multivariate analysis. The Cole-Rodgers index was used to establish the dissimilarity matrices. The principal component analysis identified the traits that contributed most to the divergence and the genotypes were clustered by Tocher's optimization. Despite the narrow genetic basis, the markers were efficient to characterize the genotypes and identify the most similar groups or duplicate and divergent genotypes. Greatest variation was found for the traits number of capsules per plant and grain yield.

Utility of some floral characters in the assessment of genetic diversity in sesame (Sesamum indicum L.)

“…This is promising from the view point of genetic improvement of flower size in sesame, which may subsequently translate into big capsule size and probably high seed yield. The importance of a trait is given by its discriminating power in the accessions and its stability of expression (Arriel et al, 2007). Floral characters are known to be expressively stable and in most cases less affected by the environment as suggested by their narrow to medium variability.…”

Genetic divergence among accessions of Carthamus tinctorius L. by morphoagronomic traits

“…For the improvement of existing safflower varieties, selection of several suitable parents for hybridization is an important step to obtain the desired recombination in segregating generations (Shivani et al, 2011). Diverging genotypes with complementary agronomic traits are necessary in hybrids formation or new segregating populations (Barbieri et al, 2005;Arriel et al, 2007). More diverging genitors result in greater variability in the segregating population, and larger probability of regrouping alleles in new favorable combinations (Barbieri et al, 2005).…”

Divergência genética entre cultivares comerciais de milho em baixas altitudes no Tocantins, safra 2007/2008

“…A divergência genética tem sido estudada em várias culturas com base nas características agronômicas, visando à seleção de genitores para formação de híbridos ou mesmo para a formação de novas populações segregantes oriundas do cruzamento dos genótipos de maior divergência (AMORIM et al, 2007;ARRIEL et al, 2007;BARBIERI et al, 2005;BONETT et al, 2006;MACHADO et al, 2002e VIANA et al, 2006. Smith et al (1999) sugerem que quando o número de germoplasma é grande e sem estabelecimento de grupos heteróticos é importante, primeiramente, identificar grupos geneticamente similares no germoplasma.…”