Nima, New Winter Oilseed Rape Variety for Cultivation in the Cold and Moderately Cold Regions of Iran

Nima variety, is resulted from the selection and purification of single plants in segregating generations derived from the cross Okapi´Modena. Single plants in F2 and their segregating generations were cultivated for five consecutive years until pure-lines were obtained in F6 generation. Selected pure lines were evaluated in a preliminary yield trial conducted in Hamedan in 2008-09. The result showed that seed yield of line SW102 (Nima) was 7% higher than Okapi (check cultivar). The study of selected lines in Karaj, Hamedan, Arak, Khosroshah near Tabriz and Islamabad-e-Gharb during 2009 and 2010 showed that seed yield of line SW102 (Nima) was 18% higher than Okapi. Based on stability parameters of environmental coefficient of variation and mean and variance of ranks for grain yield, SW102 had a good yield stability across different environments in all experinments. Evaluation of resistance to common oilseed rape diseases in Iran indicated relative resistance of SW102 to blackleg and sclerotinia diseases. Results of on- farm trials in Hamedan in 2012 showed that SW102 with grain yield of 4983 kgha-1 produced the highest seed yield. Results of on- farm trials in Isfahan showed that grain yield of SW102 and Okapi under drought stress decreased 13.4 and 23.6%, respectively, compared to normal irrigation. Based on desirable characteristics of line SW102 such as high grain and oil yield, good adaptability, relative tolerance to terminal drought stress and resistance to blackleg and sclerotinia stem rot compared to Okapi (check), this line was released as Nima and is recommended for cultivation in cold and moderately cold regions of Iran.