To investigate the effect of water stress on genetic parameters and combining ability of seed yield and some of the important traits of sunflower, eight restorer lines with different drought tolerance were crossed with three cytoplasmic male sterile lines as tester in 2014. Hybrids with their parents were evaluated in split plot arrangements using randomized complete block design with three replications at Shahrood Agricultural and Research station, Iran in 2014. Irrigation factors were assigned in the main plots at two levels, full irrigation and water deficit stress, and sunflower genotypes (24 hybrids, 11 parental lines, and one check variety) were randomized in sub-plots. Days to maturity, plant height, head diameter, seed number per plant, 1000 seed weight and seed yield were measured and recorded. Results of line × tester analysis showed that the effect of lines and testers in both conditions was significant for all studied traits, except for the head diameter in stress condition. The line × tester interaction effect in normal conditions was significant for seed number per plant and seed yield. Lines C122 and C123 and tester A19 in both conditions had the highest positive general combining ability in grain yield and could be used as suitable parental lines for developing hybrids in sunflower breeding programs. Hybrid A19 × C122 with 5224 kg.ha-1 seed yield and 91 days growth duration produced the highest seed yield under normal irrigation condition. While hybrid A19 × R217 with 1868 kg.ha-1 had the highest seed yield under water stress condition.
Abedini Esfahlani M, Fotovat M, Soltani Najafabadi M, Tavakoli A. Combining ability and gene action in parental lines of sunflower (Helianthus annuus L.) under drought stress conditions. Iranian Journal of Crop Sciences. 2018; 20 (1) :1-15 URL: http://agrobreedjournal.ir/article-1-856-en.html