灌水量、种植密度和行距对河西地区春玉米产量的影响

为确定河西地区膜下滴灌春玉米适宜的灌水量和配套栽培技术,2020年在中国农业大学石羊河流域农业与生态节水试验站开展大田试验,设置2个灌水量(W₁,W₂)、2个种植密度(D₁,D₂)和3种行距(L₁,L₂,L₃),共12个处理,3次重复.通过测定株高、叶面积指数(LAI)、干物质累积及分配等指标,研究灌水量、种植密度与行距对春玉米生长、产量和水肥利用效率的影响.结果表明,在相同灌水量下,处理D₂的株高和LAI显著高于D₁,增加种植密度提高了玉米群体干物质积累量、产量及水分利用效率(WUE).处理W₂D₂L₃的干物质累积量和产量最高,分别为96.45和17.72 t/hm²;处理W₁D₂L₃的水分利用效率最大,为3.57 kg/m³.灌水量与种植密度两者交互作用对产量及其构成因素的影响具有统计学意义(P<0.05);灌水量、种植密度与和行距三者交互作用对收获指数的影响具有统计学意义(P<0.05),对作物耗水量(ET)和WUE的影响具有统计学意义(P<0.01).灌水量、种植密度与行距均对河西地区春玉米群体结构、耗水量、产量及水分利用效率存在一定的调控效应:由大到小为种植密度、行距和灌水量.综合分析,“80%ET_c+10.0万株/hm²+宽窄行”为河西地区膜下滴灌春玉米适宜的灌水和种植模式.

Effects of irrigation amount,planting density and row spacing on grain yield of spring maize in Hexi Region

This study aimed to investigate the effects of irrigation amount, planting density and row spacing on the growth, grain yield, water and fertilizer use efficiency of spring maize under drip irrigation with plastic film mulch in the Hexi Region, so as to save water and improve maize production in this region. The experiment was carried out at the Shiyanghe Experimental Station for Water-saving in Agriculture and Ecology of China Agricultural University from April to September 2020. There were two irrigation levels, W₁ and W₂, two planting densities, D₁ and D₂, and three row spacing arrangements, L₁, L₂ and L₃ which resulted in a total of 12 treatments with three replicates. Plant height, leaf area index(LAI)and dry matter accumulation of maize were measured, and water and fertilizer use efficiencies were analyzed. The results showed that under the same irrigation amount, the plant height and LAI of the D₂ treatment were significantly higher than those of the D₁ treatment. Increasing the planting density increased the dry matter accumulation, yield, and water use efficiency of the maize population. The dry matter accumulation and yield of W₂D₂L₃ treatment were the highest at 96.45 t/hm² and 17.72 t/hm², respectively, and the water use efficiency(WUE)of W₁D₂L₃ treatment was the highest at 3.57 kg/m³. The interaction of irrigation level and planting density had a significant impact on yield and its components(P<0.05); the interaction of irrigation level, planting density and row spacing had a significant impact on the harvest index(P<0.05), which has a extremely significant impact on crop water consumption(ET)and WUE(P<0.01). It can be seen that all irrigation level, planting density and row spacing have a certain regulating effect on the population growth structure, water consumption, grain yield, and water and fertilizer use efficiency of spring maize, ranking as planting density, row spacing and irrigation level. Therefore, ″80%ET_c + 100 000 plants/hm² + wide and narrow planting″ was selected as the optimal combination for spring maize production in the Hexi Region.