豫东平原棉田土壤水分变化规律和灌溉试验研究

Soil moisture variable patterns and irrigation in cotton field of Yudong Plain

为探明棉花生育期间土壤水分对产量的影响,我们在豫东平原棉田进行了土壤水分状况和灌溉的试验研究.结果表明,豫东平原棉花生育期间土壤含水率存在3个低谷,分别出现在蕾期后期、花铃期后期和吐絮期中期,即棉花移栽后的21～27 d、69～75 d和102～108 d.从棉花蕾期至花铃期土壤储水量逐步增加到较高的水平,但在花铃期进行适时、适量的灌溉,同时控制盛絮期的耗水量有利于提高产量和土壤水分的利用效率(WUE).通过2000～2002年间棉花蕾期、花铃期、吐絮期和盛絮期的田间耗水量与产量的回归分析,得出其影响产量的系数分别为0.24、1.48、-0.12和-0.33.研究认为,棉花田间灌溉的时期对产量的效应顺序为:花铃期＞蕾期＞吐絮期＞盛絮期.

Field studies on the soil moisture status and irrigation were conducted in the cotton field of Yudong plain, in order to try to find out the yield response to soil moisture status during cotton development stages (CDS).The results showed that there were three low folds of soil moisture during CDS, which appeared respectively at the anaphase of budding and flowering-boll forming stages (FBFS), and metaphase of ball beginning open stage (BBOS), those were 21~27 d, 69~75 d and 102~108 d after transplanting. The soil water reserves (SWR) came to higher level gradually from budding stage (BS) to FBFS, but at the betimes proper irrigation during FBFS and lower water consumption at ball opening peak stage (BOPS) may increase the yield and water use efficiency (WUE). From the regression correlation analysis between soil water consumption of BS, FBFS, BBOS, BOPS and yield in 2000～2002, the gained coefficients which influenced the yield were 0.24, 1.48, -0.12 and -0.33, respectively. The result show that the effect sequence of irrigation in cotton field on CDS is FBFS>BS>BBOS>BOPS.