水钾互作对高产夏玉米茎秆结构和功能的影响

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

以郑单958(ZD958)为试验材料,采用干旱棚池栽试验,研究了水钾互作对夏玉米茎秆结构和功能的影响.结果表明:灌水可显著提高茎秆的伤流量,施钾在一定程度上可以缓解水分缺乏对茎秆伤流量的影响,在灌水2250 m^3·hm^(-2)时施钾可显著提高各生育时期茎秆的伤流量.水钾互作可显著提高茎秆穿刺强度和茎粗,在灌水2250 m^3·hm^(-2)时施钾处理的穿刺强度和茎粗较不施钾处理分别高46.0%和36.4%,施钾条件下灌水2250 m^3·hm^(-2)较灌水450m^3·hm^(-2)处理的穿刺强度和茎粗分别高30.7%和8.6%.灌水2250 m^3·hm^(-2)时施钾显著提高了茎秆维管束数目、面积及维管束内厚壁细胞、皮层和硬皮组织厚度.即水钾互作能够显著提高夏玉米植株的抗倒伏能力,本试验条件下,施180kg K_2O·hm^(-2)、适当增加灌水量可显著提高夏玉米抗倒伏能力和产量.

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 m^3·hm^-2 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 m^3·hm^-2the stalk rind penetration strength and stem diameter with K application were respectively increased by46.0%and 36.4%compared with no K application.Under K application,the stalk rind penetration strength and stem diameter in the irrigation amount 2250 m^3·hm^-2were respectively increased by30.7%and 8.6%compared with 450m^3·hm^-2The number,area of vascular bundle and the thickness of thick-walled cell,cortex and rind,were significantly improved by the irrigation amount2250 m^3·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.