不同水分处理对玉米根系分布及产量的影响研究

Effects of Different Water Treatments on Root Distribution and Yield of Maize

为了从机理上揭示土壤水分对玉米生长及产量的影响,文中采用了室内盆栽的形式,在玉米三叶期后开始控制灌溉的含水量下限,对其进行不同水分处理。试验对玉米的根长密度、总根长、根系干重、产量构成因子、产量及灌溉水利用系数进行了系统的分析。结果表明:不同水分处理不改变玉米根系随土层增加所呈现的对数递减的分布形式,却改变了其在不同土层的分配比例;水分处理W1玉米总根长及根系干重均大于W2,但差别不显著;W3玉米总根长及根系干重较W1、W2均显著减小;相对于其他处理,W1水分充足,其玉米产量最高,穗粒数最多,且玉米籽粒最饱满;W2较W1玉米产量、穗粒数及百粒重均有所降低,但降低的程度不显著;W3和W4玉米均严重减产,且籽粒干瘪不饱满。各水分处理灌溉水分利用效率排序为W2>W1>W3>W4。综合考虑玉米生长指标及灌溉水利用效率,确定在玉米生育期内以田间持水量的70%作为灌溉下限较为合理。

In order to reveal the effect of soil moisture on the growth and yield of maize,by controlling the lower limit of the water content of the irrigation,different water treatments were adopted to deal with potted maize after the trefoil stage. The root length density,total root length,root dry weight,yield components,yield and water efficiency of irrigation were analyzed systematically. The results show that： different water treatments did not change the logarithmic decreasing distribution of the maize root with the increase of soil layer,but the distribution ratio of the maize root in different soil layers was changed. For total root length and root dry weight,W1 is greater than W2 with non-significant difference,W3 is much less than W1 and W2. For maize yield,grain number per spike and hundred-grain weight,W1 has sufficient water compared with other treatments,it has highest yield,most grain number per spike and highest grain plumpness. W2 is not much less than W1. W3 and W4 have severe reduction with wizened grain. The irrigation water efficiency of each water treatment is W2 W1 W3 W4. Considering the growth index and irrigation water efficiency,it is reasonable to take 70% of the field capacity as the lower limit of irrigation during the maize growing period.