Correlation and Path Coefficient Analysis of Agronomic Characteristics and Sesamin Content in Black, Red and White Sesame Grains

Abstract

The information on the relationships of agronomic characters with sesamin content is important for sesame breeding to improve grain yield and sesamin content. The experiment was conducted at the Division of Plant Production Technology, Faculty of Agro-Industrial Technology, Kalasin University in the early rainy season during May to August 2016. The objectives of this study were to investigate the correlations among some characters of sesame and to verify direct and indirect effects. The experimental design was RCBD with 4 replications for this study. Data were recorded for agronomic characters and the seed samples were analyzed for sesamin content using HPLC. The results showed that significant positive correlation between yield/plant with days to harvest (r =0.733, P ≤ 0.01), plant height (r =0.611, P ≤ 0.01), 1,000-grain weight (r =0.501, P ≤ 0.05) and width of grain (r =0.441, P ≤ 0.05). Days to harvest had the highest positive direct effect on yield/plant (0.840) followed by plant height (0.376) and 1,000-grain weight (0.287). Significant negative correlation between sesamin content with 1,000-grain weight (r =-0.715,P ≤ 0.01), length of grain (r =-0.639, P ≤ 0.01), width of grain (r =-0.564, P ≤ 0.01) and yield/plant (r =-0.468, P ≤ 0.05). Thousand-grain weight had the highest negative direct effect on sesamin content (-0.471) followed by length of grain (-0.369). The results obtained from correlations and path analyses
showed that the efficiency in the selection for yield/plant in sesame should increase through selection of days to harvest, plant height and 1,000-grain weight. The relationship between seed size with sesamin content might obstacle in sesame breeding for increase both seed size and sesamin content.