供水方式对春小麦根源信号和水分利用效率的影响

用圆柱状管栽实验研究了上层供水和下层供水对春小麦根源信号和水分利用效率的影响。供试春小麦品种为陇春8139-2和高原602.处理方式为：1)整个管体内土壤含水量保持在80%～90%田间持水量(FWC)(IF)；2)土壤表面以下10cm处浇水使管内整体土壤含水量保持在50～60%FWC(IT);3)在管体长7／10处浇水使管内整体土壤含水量保持在50～60%FWC(IB).相对于IF和IT处理，苗期到分蘖期IB处理叶气孔导度显著下降，但叶水势基本不变，表明有明显的非水力根信号现象。在拔节期及以后，IB处理土壤上层根生物量比例下降，中层根生物量增加，非水力根信号消失。IB处理的水分利用效率显著高于其它处理，这意味着播种前通过水量较多的灌溉增加深层土壤水分将有利于提高水分利用效率。

The effect of water supply patterns on non-hydraulic root signal and water use efficiency of spring wheat

In this paper, the experimental results of the influence of water supply at various soil depth on non-hydraulic root signal and water use efficiency are presented. Two genotypes of spring wheat and three soil moisture regimes are adopted. Plants are grown in cylinder pots out-door. The analysis on experimental data shows that frequent irrigation on topsoil after sowing results in low water efficiency, while irrigation with equal amount of water just before sowing will elevate the water use efficiency.