Potassium fertilization mitigates the adverse effects of drought on selected Zea mays cultivars

Authors : Lixin Zhang, Mei Gao, Shengxiu Li, Ashok Kumar Alva, Muhammad Ashraf

Pages : 713-723

Doi:10.3906/bot-1308-47

View : 11 | Download : 6

Publication Date : 9999-12-31

Article Type : Makaleler

Abstract :In the present study, the role of potassium (K) in mitigating the adverse effects of drought stress (DS) on 2 maize (Zea mays L.) cultivars, 'Shaandan 9' (S9; drought-tolerant) and 'Shaandan 911' (S911; drought-sensitive), was assessed. K application increased dry matter (DM) across all growth stages and grain yield (GY) in both cultivars under DS, but not under control conditions. Drought-tolerant cultivar S9 was superior to drought-sensitive cultivar S911 under DS in terms of DM and GY regardless of K addition. Additionally, K application increased relative water content, nitrate reductase activity, and concentrations of potassium ion, free proline, soluble protein, and endogenous glycine betaine in both cultivars. These positive effects due to K fertilization under DS were greater for S911 than for S9. In contrast, the differences in the above parameters between K-treated plants and plants under control conditions were either nonsignificant or marginal. This study provides direct evidence of the beneficial physiological function of K fertilization in mitigating the adverse effects of DS by increased nitrate assimilation and osmotic regulation, but not due to its nutritive role.
Keywords : Key words: Relative water content, nitrate reductase activity, osmotic solutes, Poaceae, potassium fertilizer