HETEROSIS, COMBINING ABILITY AND CORRELATION STUDIES IN THREE-WAY CROSS HYBRIDS IN SUNFLOWER (Helianthus annuus L.)
Loading...
Date
2013
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Punjab Agricultural University, Ludhiana
Abstract
Study was undertaken to assess the magnitude of heterosis and combining ability in three-way cross hybrids of sunflower. A set of eleven A lines 302A X 11B, 302A X 42B, 302A X 234B, 302A X 44B, 44A X 40B, 11A X 234B, 43A X 44B, 234A X 40B, 44A X 234B, 44A X 42B, 44A X 11B and four restorers P89R, P69R, P93R and P110R were crossed in all possible combinations to obtain 44 TWC hybrids to evaluate for general combining ability (GCA) and specific combining ability (SCA) in a randomized block design over two years in spring 2011 and spring 2012. Genetic variability among genotypes was assessed for days to flower initiation, days to 50% flower initiation, days to maturity, plant height, head diameter, no. of leaves per plant, chlorophyll content, leaf area, leaf area index, seed yield per plant, 100 seed weight, oil content, stay green and fatty acid composition. CMS 11A X 234B had significant general combining ability effects for seed yield, head diameter, chlorophyll content, leaf area and oil content followed by CMS 44A X 40B for seed yield, plant height and days to flower initiation. Among the restorers P89R was good combiner for seed yield, head diameter, no. of leaves, chlorophyll content and 100 seed weight followed by P93R for head diameter, leaf area index, 100 seed weight and oil content. Two crosses 302A X 44B X P89R and 302A X 234B X P69R had significant sca effects for various characters. Importance of additive gene effects was found in the inheritance of traits like plant height and 100 seed weight. However for all other characters such as days to flower initiation, days to maturity, head diameter, no. of leaves, chlorophyll content, leaf area, leaf area index, seed yield and oil content non-additive gene effects predominated. Hybrids 302A X 44B X P89R, 11A X 234B X P89R and 234A X 302B X P93R excelled the standard checks for most of the important traits. The hybrids in general involving the parents 234A X 44B, 234A X 302B, P93R and P89R exhibited high positive heterosis for seed yield per plant. High significant correlation was observed between seed yield and 100 seed weight and plant height followed by head diameter, no. of leaves, chlorophyll content, leaf area and leaf area index.
Keywords: Heterosis, combining ability and three way cross hybrid.
Description
Keywords
null