垄作覆盖模式对夏玉米耕层含水量及产量形成的影响效应分析

Effect Analysis of Sowing on Ridges and Strew Mulching System on Soil Moisture Content in 0-20 cm Deep Soil Profile and Grain Yield in Maize

以免耕平作为对照,研究不同垄作覆盖模式对夏玉米耕层土壤含水量、干物质积累与分配以及产量的影响效应。结果表明,垄作和覆盖栽培的保水效果在玉米生育后期尤其是干旱时更为显著。相同条件下宽窄行垄作栽培处理的增产效果明显优于等行距垄作处理,无覆盖条件下等行距垄作处理的实际产量较平作处理提高0.5%,宽窄行垄作处理提高8.91%;覆盖条件下等行距垄作处理与宽窄行垄作处理的实际产量较平作处理分别提高3.62%和11.59%。相关及通径分析表明,子粒实际产量与开花至成熟期耕层土壤平均含水量、大喇叭口期叶片干重以及成熟期叶片干重呈显著正相关。提高开花至成熟期耕层土壤平均含水量、降低开花期茎鞘干重、促进叶片的干物质积累是垄作覆盖模式下玉米获得高子粒产量的主要原因。

Effect of different ridge cultures and mulch patterns on soil moisture content,accumulation and partition of dry matter and grain yield in maize were investigated.The results showed that the water retaining effect of ridge culture and mulch pattern during the later growth stage,especially under drying conditions,was more remarkable than growth prophase.Without strew mulching,the system of bed-planting with wide/narrow row alternation improved grain yield by 8.91%,and bed-planting with equal row improved grain yield only 0.5% in contrast with the flatting cropping system.But with strew mulching,grain yield of bed-planting with wide/narrow row alternation treatment and bed-planting with equal row treatment increased 11.59% and 3.62%,respectively.Correlation and path analysis showed that the grain yield was significantly and positively correlated with mean soil moisture content in the scope of 0-20 cm deep soil profile from flowering to maturity and dry leaf weights at trumpet and maturity.Increasing the soil moisture content from flowering to maturity,decreasing the dry weights of stems and spikes and accelerating the accumulation of leaf were the main reasons to gain high grain yield for sowing on ridges and strew mulching system.