滴灌条件下根区水分对春小麦根系分布特征及产量的影响

通过小区滴灌根区水分控制试验,研究亏缺、丰水、适水不同水分处理对春小麦根系特征的垂直分布、产量构成和水分利用效率等的影响.结果表明,孕穗-扬花是滴灌春小麦根系生长的关键时期,其根系主要分布在0～40 cm土层,根长密度和根干重在土壤剖面上的分布呈y=A×e-Bx的负指数递减趋势.不同根区水分对春小麦根系生长及分布有显著...

Effects of soil moisture of root zone on root growth and yield of spring wheat under drip irrigation

Through water controlled trial in root zone under drip irrigation, the effect of different soil moisture on vertical distribution of roots, yield components and water use efficiency of spring wheat were studied. The results showed that booting-flowering was a critical period of spring wheat root growth and most roots were distributed within soil layer of 0~40 cm under drip irrigation. The distribution of root length density and root dry weight showed decreasing trend of negative index with soil depth which could fit by y= A×exp(-Bx); The effect of soil moisture in root zone on growth and distribution of root was significant. Limited irrigation treatment had a higher proportion of deep soil root volume, but root dry weight decreased significantly. Excessive irrigation had a largest root volume which mainly concentrated in shal-low soil, that easily lead to lodging, and the proportion of assimilated matter distributed to spike was lower. Root distri-bution of appropriate irrigation treatment was more reasonable, whose root length, root surface area and root dry weight density maintained a high level in the flling stage , and single spike weight and WUE were significantly higher than that of limited amount trealment and excessive amount treatment, so its yield was the highest; By drip irmigation to control water status in wheat root zone, it can be achieved to prormote formation of higher yield and to obtain higher efficiency of water use efficiency.