Relationship of Parental Genetic Distance with Heterosis Appearance in Sunflower under Well-Watered and Water-Stressed Status

Sunflower is one of the most important field crop over the world which it`s hybrid seed production is very important. Knowledge about heterosis and identification of superior parental combination is major step in producing hybrid seed that is time consuming process and expensive. Current study was aimed to investigate the relationship between genetic distances based on simple sequence repeat (SSR) markers with heterosis to provide the prediction of hybrids performance regarding to genetic distance. In present study, five sunflower inbred lines were crossed in 5×5 half diallel design and then, parental lines and their progenies were investigated using a randomized complete block design with three replications in both normal and water stress states in greenhouse. The Jaccard genetic distances among parental lines were calculated using 31SSR markers. Genetic distances were varied between 0.58 and 0.82. Based on calculated genetic distances, parental genotypes were located in three groups. Significant or nonsignificant relationships of obtained genetic distances with specific combining abilities and mid parent heterosis for seed yield and relative water content were tested in both states. Results revealed that microsatellite markers could be effectively used to fingerprinting and identification of genetic distance between parental lines. Result showed that relationship between genetic distance based on microsatellite marker with mid parent heterosis and specific combining ability for evaluated traits were not significant and have no efficiency in prediction of heterosis.