化学节水制剂对不同灌溉条件下冬小麦水分关系的影响

Effect of Chemical Agents on Water Relation of Winter Wheat under Different Irrigational Conditions

试验通过比较保水剂、抗旱剂(FA旱地龙)和钙赤霉素3种化学制剂对半湿润灌区不同灌溉条件下冬小麦生育后期耕层土壤水分状况和冬小麦水分关系影响的差异,结果表明,保水剂和旱地龙处理对提高花后生育期内耕层土壤水分含量、冬小麦的旗叶水势以及叶片WUE的效果更明显,尤其是保水剂处理,在灌2水条件下,花后生育期内耕层土壤水分含量和叶水势的平均值比对照CK2提高9.7%和10.8%;灌0水条件下,则比CK0提高5.3%和7.4%。钙赤霉素处理则显著减小了叶水势和WUE的日变化幅度。回归分析显示,土壤水势决定叶片水势的高低,而叶片水势与叶片WUE显著正相关。试验结果还表明,3种化学制剂均不同程度的提高了冬小麦的产量,但是在本试验条件下,水分条件是产量的决定因素。同一灌溉水平下,4个处理的产量和穗数差异均不显著;不同灌水处理下,产量差异均达到极显著水平。

A field experiment was carried out to study the effects of three chemical agents （including water-retaining agent, FA Handilong and mixture of CaC12 and GA） on soil moisture content of plough player and water relation of winter wheat under different irrigational conditions at later growth stage in subhumid zone. The results showed that water-retaining agent and FA Handilong had better effects on increasing the soil moisture content of plough player, flag leaf water potential and leaf WUE, especially the water-retaining agent. In contrast to CK, the average value of soil moisture content and leaf water potential under water-retaining treatment after flower stage was increased by 9.7% and 10. 8% individually under irrigating twice, while it was increased by 5.3% and 7.4% individually under no irrigation in the experiment. The mixture of CaCl2 and GA could significantly decrease rangeability of daily change of leaf water potential and WUE. By regression analysis, soil water potential determined the leaf water potential, meanwhile there was a positive correlation relationship between leaf water potential and leaf WUE. The results also showed that all these three chemical agents had different way to improve yield of winter wheat, but water was the critical factor on yield in this experiment. Under the same irrigational condition, there was no variance in yield or ears number among four treatments, but under the different irrigational conditions, the variance of yield was dramatic.