Study of yield and some physiological and agronomical traits of spring oilseed rape under water deficit stress

Seed and oil yields, its components and two physiological indices including leaf canopy temperature (Tc) and relative water content (RWC) were evaluated in two spring oilseed rape cultivars (RGS 300 and Hyola 401) under non-stressed and water deficit imposed during stem elongation, flowering and seed filing stages. The experiments were conducted as a factorial consisted of 2 factors including irrigation and genotypes based on a randomized complete block design with three replications. The study was conducted in research center for agriculture and natural resources of East Azarbaijan, Iran (46° 2′ E, 37° 58′ N). The results indicated that occurring water deficit in all stages, increased Tc and decreased RWC, siliques per plant, seeds in silique, harvest index, seed and oil yields. Significant correlations among RWC, TC, seed and oil yields were observed. Tc and RWC indices could be used to determine water deficit effects in spring oilseed rape cultivars. Since occurring drought during flowering and seed filing stages had the most negative effects on seed and oil yields, therefore it seems that irrigation of spring oilseed rape cultivars during these stages, is important for achieving acceptable yield. Hyola 401 indicated higher amounts of seed and oil yields.