Effect of macro and micro- nutrients on seed yield and other agronomic traits of safflower in Isfahan

Safflower (Carthamus tinctorius L.) is an oil seed crop and because of its adaptability, it is widely grown in Isfahan provience. Appropriate soil fertility can increase seed yield and its quality. This study was conducted to investigate the effects of macro and micro-nutrients on agronomic traits of safflower. A split-plot experiment in a randomized complete block design with three replications was used in which the nine fertilizer treatments were applied in main plots and the genotypes of Arak-2811 and Isfahan-22 in sub plots. The results showed that applying the fertilizer for nutrient elements of N, P, K, Fe, Zn, and Mn had no significant effects on the studied traits. Despite no statistically significant effect of fertilizer treatment on yield components, seed yield/plant, seed yield and oil yield was observed, the variation of means for these traits was considerable. The minimum and maximum mean of all these traits were obtained for fertilizer treatments of P+K and NPK+Fe, respectively. Seed yield/plant, seed yield/ha and oil yield/ha for the fertilizer treatments had a variation of 12.91 to 20.22 g, 2601 to 3333 kg and 797 to 1046 kg, respectively. Increasing of seed and oil yield in NPK+Fe treatment was mostly due to the effect of N and Fe. The oil content of the seeds for fertilizer treatments varied from 32.6% to 32.02%. In case of using no fertilizer, the oil content of seeds was 31.28%. No significant interaction effect between fertilizer treatments and genotypes was observed for all the traits, indicating that the effect of fertilizer treatments was the same on both genotypes and it seems that the same fertilizer treatment can be recommended for different genotypes of safflower to increase oil yield.