POTASSIUM OXIDE NANOPARTICLES ALLEVIATE DROUGHT STRESS IN MAIZE IMPACTS ON GROWTH AND YIELD RELATED TRAITS

Abstract

Drought is a major limit to maize production and reproductive traits are especially sensitive. Potassium helps plants manage water loss. This pot study tested a foliar potassium oxide (K₂O) spray, applied at the flowering stage, on two maize varieties, Sahiwal Gold and Gohar-19. The four treatments were a control, K₂O alone, drought alone and drought with K₂O. Four growth traits and four yield traits were analyzed by analysis of variance and planned contrasts separated the effects of drought and K₂O. Drought lowered stem fresh weight by 58.5%, stem dry weight by 82.3%, grains per cob by 60.7% and cob weight per plant by 49.1%. The K₂O contrast was significant for grains per cob, cob weight per plant and 100 grain weight. Under drought, grains per cob were 72.0% higher with K₂O. K₂O did not significantly change stem weights. Variety effects and interactions were not significant. This study suggests that a K₂O spray at flowering might help grain number under drought. This needs to be tested in the field, with the controls above, before any advice to growers can be given.