Study and yield comparison o sunlower cultivars in onarm summer planting conditions o Golestan province.

In order to study the possibility o summer planting and production o oilseed sunlower genotypes as a second crop (ater harvesting wheat), an experiment was conducted in 3 regions including Gonbad, Gorgan and Aliabad in summer 2010. In this study, 8 genotypes consisted o commercial varieties, promising hybrids and lines were evaluated in an RCB design with 3 replications in each region. Each plot consisted o 5 rows with 6 meters long. Between rows 50 and within rows distances were 30 centimeters. Common note-takings was done along growth duration. On physiologic maturity stage, yield related traits were measured beore harvesting. The data obtained was analysed using -test and means classiication on traits which had signiicant dierences perormed using LSD method. In Gonbad eect o genotype was signiicant on all traits evaluated with the exception o head and stem diameter. The highest 1000 seed weight(63.4gr), seed yield(2.969 t/ha) and oil yield(1.368 t/ha) was belonged to CMS1221/1 x R-14. This hybrid had the least plant height. In Gorgan eect o genotype was signiicant on all traits evaluated. Gabor and arrokh with 3.413 and 0.719 t/ha o seed yield gained the irst and last rank due to seed yield, respectively. Although hybrids CMSG5 x R-43(3.006 t/ha) and Azargol(2.975 t/ha) were ranked in the same group with Gabor. In Aliabad in spite o sowing on time, unortunately due to improper soil conditions, emergenc o seeds was not satisactory, hence data obtained was not accurate. Thereore they had not analysed and omitted rom current results. Based on results obtained, in order to improve yield and acreage o oilseed sunlower, persuasion o armers via increasing net income, it could be recommendable to plant ALine1221/1 x R-14 in Gonbad due to its highest perormance, Gabor, CMSG5 x R-43 and Azargol in Gorgan due to their proper productivity to obtain highest possible seed and oil yield in summer planted sunlower arms. Key words: sunlower, cultivar, summer planting, seed and oil yield