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 : 14 | Download : 5

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :In the present study, the role of potassium insert ignore into journalissuearticles values(K); in mitigating the adverse effects of drought stress insert ignore into journalissuearticles values(DS); on 2 maize insert ignore into journalissuearticles values(Zea mays L.); cultivars, `Shaandan 9` insert ignore into journalissuearticles values(S9; drought-tolerant); and `Shaandan 911` insert ignore into journalissuearticles values(S911; drought-sensitive);, was assessed. K application increased dry matter insert ignore into journalissuearticles values(DM); across all growth stages and grain yield insert ignore into journalissuearticles values(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