Genetic variability and QTL mapping for seed germination parameters under drought stress in sunflower

The objective of this research was to identify the genetic control of germination parameters under control and drought conditions in sunflower. A population of 100 recombinant inbred lines obtained from a cross between PAC2 and RHA266 was used in the present study. Our experiments were performed using a randomized blocks design with three replications. Germination parameters were the reference times of germination, percentage of seed germination (PSG), oil content (OC) and 1000 grain weight (GW). Positive significant correlations were obtained between reference times of germination. A high significant positive correlation was observed between PSG and OC in both conditions, whereas the correlation between 1000 GW and the reference times were significant only in drought stress condition. Several nonspecific QTLs for drought were detected for germination parameters. HA1837 SSL27 and ORS671_1 are the SSR markers associated to QTL detected for germination parametrs independent od germination condition. The most important specific QTL was associated to ORS677 SSR marker with 24% of phenotypic variance for PSG trait in stressed condition.