Abstract
Information regarding the effect of foliar application of zinc and manganese on the growth and development of safflower under water deficiency is not available. Therefore, field experiments were conducted in 2001–2002, 2002–2003 and 2004 (as the field emergence experiment) to determine agronomic traits and seed quality of safflower under above-mentioned conditions. Irrigation treatment (unstressed control, and withholding irrigation during vegetative growth, flowering and seed filling stages), safflower genotype (Zarghan 279, Varamin 295 and L.R.V.5151) and foliar application treatment (untreated plots, foliar application of water, zinc sulfate and manganese sulfate) were studied in a split factorial design with three replications, with irrigation treatment as the main plot, and factorial combination of the other two factors as the subplot. Generally there was a decrease in seed yield, total biomass, number of capitula per plant and plant height each growing season by withholding irrigation at various growth stages at all treatment combinations, especially when water deficit stress was imposed at the flowering stage. The foliar application of Zn, Mn and in some cases water mitigated the negative effect of water deficit stress on agronomic traits in all three genotypes. Averaged over 2001–2002 and 2002–2003, without foliar application, Zarghan 279 was found suitable for unstressed conditions and appeared to grapple better with water deficit stress during vegetative growth stage and L.R.V.5151 showed a better ability to recover from stress at the flowering and seed filling stages. Foliar application of Zn and Mn increased concentration of these two elements in seed, germination rate, germination percentage, seedling dry weight and final seedling emergence, and water deficit stress had negative impacts on most these parameters. All treatments had significant effects on proteins and the major protein fractions of safflower were the albumins (20–37 mg g −1) and globulins (15.7–36.3 mg g −1). With regard to oil content and its composition, small differences were evident between treatments. Linoleic acid and oleic acid comprised about 90% of the fatty acid composition. In general, significant relationships existed between traits. The results obtained here suggest that foliar Zn and Mn application can improve the seed yield and seed quality of safflower grown under drought stress.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have