Shams, New Medium Maturity Sunflower Hybrid Adapted to Spring Cropping in Temperate and Cold Regions and Summer Cropping in Temperate Regions of Iran

Sunflower hybrid cultivars which have been improved and released in Iran are categorized in two early and late maturity groups. Early mature hybrids are low yielding while late matures have problems of limitation in growing season, higher plant height and higher water requirement. So, there is a lack of mid-mature and dwarf hybrids in Iranian sunflower hybrids. New hybrid, Shams was improved by crossing between CMS line AF81-112 and restorer line RF81-82 using simultaneous selection method, self and back-crossing in offseason conditions. In the preliminary evaluation, this hybrid with seed yield equal toexotic hybrid Alstar, moderate maturity and dwarf height was identified as a promising hybrid. In regional experiments in Karaj, Khoy, Zanjan and Eslam Abad seed yield of Shams (4067 kg ha-1)was equal to the exotic hybrid Hysun33 while it was also earlier and shorter than other checks. In adaptability evaluations, its seed yield was equal to Hysun33 and also it was earlier and shorter than Azargol and Hysun33. Under on-farm trials Shams was superior to check varieties in Kermanshah, Mazandaran and west Azarbayjan provinces. This hybrid had a higher seed yield compared to Farrokh and Ghasem hybrids under drought stress condition. Shams and its restorer line were resistant against powdery mildew under greenhouse condition. Shams hybrid considered as a stable and superior hybrid with an average seed yield of 3.5 tons ha-1 had a similar seed yield to those of exotic hybrids, higher yield compared to early mature hybrids of Ghasem and Farrokh and also lower plant height, moderate maturity and suitable capitule shape compared to the late mature hybrid Azergol. This hybrid was released as a new sunflower cultivar for spring cultivation in the temperate and cold regions and for summer cultivation in the temperate regions of Iran in 2017.