Study of yield and water productivity in inbred lines of sunflower under optimum and water stress conditions

To evaluating sunflower inbred lines under optimum and water stress conditions, two separate experiments was conducted at Agricultural Research Station of Bastam (Shahrood). In each experiment, 20 French inbred lines in a randomized complete blocks design with three replications were evaluated. During the growing period, agronomic traits including the number of days to flowering, maturity, plant height, stem diameter, head diameter, number of grain per head, biomass, grain yield and 1000 grain weight were measured. According to the results, there was a significant difference between lines in all traits. . Lines C111, C138, C142 and C148 had the highest grain yield and water productivity in both moisture conditions. Line C123 showed maximum grain yield reduction (87%), with 1736 and 224 kgha-1 grain yield under optimum and water stress conditions, respectively. In contrast, line C122 showed minimum grain yield reduction (35%), with 1493 and 978 kgha-1 grain yield under optimum and water stress conditions, respectively. In the path analysis of traits, two traits, grain number per head and 1000 grain weight showed most direct effect on grain yield in both conditions. Due to high heritability of these two traits, we can use them in selection for grain yield increase.