Examining grain and oil yields of different safflower cultivars affected by irrigation withholding treatment in two planting dates

Abstract

Safflower is a native plant to Iran, resistant to arid environment that will be used as an oil seed for future hopefully. The experiment was a split plot based on complete randomized block design with four replications. Main plot includes two spring and summer plantings and sub-plots include three irrigation withholdings (control, irrigation withholding at the start of flowering and irrigation withholding at the start of grain filling period) and ten safflower cultivars including Soffe, Goldasht, Sina, Faraman, Golmehr and Mexican cultivars, Mec117, Mec295, Mec184, Mec11, Mec7, were located in main plot as sub-plots. The results indicated that delaying in plantings reduced biologic yield, grain yield, harvest index and oil yield in Safflower cultivars, significantly. At the start of flowering, irrigation withholding reduced grain and oil yield significantly. Irrigation withholding treatments and safflower cultivars did not affect on oil percentage. However, Mexican cultivars had suitable yields in spring planting date, but it reduced during summer planting date, extremely; while, Iranian cultivars had higher grain and oil yields during both planting dates. Among the cultivars, Soffe and Goldasht had the highest grain and oil yield.