The use of agro-morphological characters for the assessment of genetic diversity in sesame (Sesamum indicum L.)

摘要

Agro-morphological variation in the sesame germplasm was estimated using 21 morphologic and agronomic descriptors to characterize and identify genetic diversity. A total of 103 sesame landraces were collected from the sesame growing areas throughout Turkey. This collection was evaluated for seed yield, yield related characters and morphological characters in the two consecutive years (2004 and 2005). A great amount of variation was recorded for 17 morphologic and agronomic traits while four characters were found to be monomorphic as the plants with branching, white with pink shading flower color, shattering and indeterminate growth habit. Multivariate analyses were performed in order to establish similarity and dissimilarity patterns. Principal component (PC) analysis revealed that first three PC axes explained 43.4% of the total multivariate variation while the first seven PC axes explaining 69.9%. The developmental characters such as days to emergence, flowering and capsule initiation and seed yield were the major determinants of the genetic diversity in the collection. Cluster analysis identified eight main clusters based on agro-morphological characters indicating the diversity could mainly be attributed to diverse agro-climatic conditions. Single plant selection was made from these populations based on different agronomic characteristics and yield potential. These results have an important implication for sesame germplasm characterization, improvement, agro-morphological evaluation and conservation.