Effect Of Potassium On Resistance Of Maize Seedlings To Low Temperature Stress

Abstract: the sand culture, solution culture and isotopic experiment has been used to study the effect of potassium application on plant growth, nutrient uptake, physiological metabolism and chilling resistance in growth incubator and green house.The results demonstrated that the chilling stress strongly inhibited shoot growth and mineral nutrient uptake of maize plant , and caused certain water stress. Application of fertilizer potassium resulted in significant Increase in the content of potassium in plants and photosynthetic ability to maintain normal growth of maize plants. Consequantly,accumulation of cation and soluble sugar occurred with potassium application,suggesting the endurance to water stress by enhancing osmotic regulative ability. Potassium application would decrease per-oxidase activity and membrane injury of maize leaves induced by chilling stress. Therefore, potassium application can increase the chilling resistance of maize plants.The results also indicated that potassium application could improve plants growth under different temperatures,especially under low temperature. With increase in application from 0 to 0. 4gK₂O/kg, growth of shoots and roots of maize plants increased, thereafter it declined again.