Genetic analysis of morpho-physiological characteristics of sunflower under optimum and limited irrigation conditions

Five CMS lines and four restorer lines (tester) were crossed in a line × tester scheme in order to analyze general and specific combining abilities and gene effects in sunflower for some agronomic traits. Hybrids were evaluated in a randomized complete block design, with three replications under optimum and limited water conditions in the Agriculture Research Station, Khoy, during 2015 and 2016 growing seasons. Plant height, head diameter, seeds per head, days to beginning of flowering, days to maturity, proline percent, protein percent, and Chlorophyll b were found to be controlled mainly by dominance effects. CMS lines AGK30 and testers RGHK25 and RGHK50 turned out to be the best general combiners for seed and oil yield. The highest positive and significant GCA for plant height, head diameter, and the number of seeds per head were achieved for RGHK25. The hybrid combination of AGK44 × RGHK56 showed high specific combining ability for seed and oil yield. In the study of general combining ability, the AGK110 line has a positive and consistent general combining ability, and AGK2 has a negative and significant general combining ability with catalase . In the test of the testers, the tester (RGHK50) had the highest GCA positive and meaningful drug tester (RGHK56), which had a significant negative and significant combining ability with catalase . In the study of hybrid hybrid combining ability (RGHK46 × AGK260), the highest positive and significant positive and significant hybrid confinement (RGHK46 × AGK44) had the highest SCA negative and significant levels. In the RGHK46 × AGK260 hybrid combinability study, the highest positive and significant positive and significant hybrid confinement (RGHK46 × AGK44) had the highest SCA negative and significant effect on catalase identity. The AGK44 line has the ability to combine publicly and positively with AGK110 capability. The general combining ability was negative and significant with SOD. In the test of the testers, the RGHK 56 tester had the highest GCA positive and significant mean of the RGHK25 tester, which had a negative and significant general combining ability with superoxide dismutase. In the study of hybrid hybrid combining ability (RGHK50 × AGK260), the highest positive and significant positive and significant positive combining ability (RGHK50 × AGK44) had the highest SCA negative and significant values for SOD. In explaining the traits, plant height, Number of seeds per head and percentage of proline under stress conditions played a more significant role. Plant height and number of seeds per head were controlled by both growth and dominance effects. also In the study of general combining ability, the highest GCA positive and significant values were related to the AGK30 line and the most general negative and significant general combining ability was AGK2 line (Table 4-14). In the test of the testers, the tester (RGHK 46) had the highest GCA positive The drug tester (RGHK25) had the most significant negative and significant general combining ability with proline). In the study of hybrid combining ability (RGHK46 × AGK2), the highest positive and significant positive and significant hybrid confinement (RGHK25 × AGK260) had the highest SCA negative and significant values .