[Effects of water-potassium interaction on stalk structure and function of high-yield summer maize]

The effects of water-potassium interaction on stalk structure and function of high-yield summer maize were studied in the waterproof cultivation pools with Zhengdan 958 (ZD958) as the experimental material. The results showed that the quantity of bleeding sap in stalk was significantly improved by irrigation. Potassium (K) application could reduce the influence of drought stress on the quantity of bleeding sap in stalk to a certain extent. The quantity of bleeding sap in stalks during different growth periods were significantly improved in the treatment of 2250 m³ · hm⁻²2 irrigation amount with K application. The stalk rind penetration strength and stem diameter were significantly improved by water-potassium interactions. Under the irrigation amount of 2250 m³ · hm⁻², the stalk rind penetration strength and stem diameter with K application were respectively increased by 46.0% and 36.4% compared with no K application. Under K application, the stalk rind penetration strength and stem diameter in the irrigation amount 2250 m³ · hm⁻² were respectively increased by 30.7% and 8.6% compared with 450 m³ · hm⁻². The number, area of vascular bundle and the thickness of thick-walled cell, cortex and rind, were significantly improved by the irrigation amount 2250 m³ · hm⁻² with K application. In conclusion, application of 180 kg K₂O · hm⁻² and increasing the irrigation amount properly could increase the lodging resistance and yield of summer maize in this field experiment condition.