摘要
[目的]探究施氮对河西走廊灌溉区青贮玉米光合日变化和农艺性状及干物质量的影响,寻求河西走廊灌溉区最佳施氮量.[方法]以青贮玉米金铃 67号为研究对象,于2022年在河西走廊灌溉区开展大田试验,设置 5 种施氮水平N0(0 kg/hm2)、N1(218 kg/hm2)、N2(249 kg/hm2)、N3(280 kg/hm2)、N4(311 kg/hm2),分析不同施氮水平对青贮玉米抽雄期叶片相对叶绿素含量(SPAD)、光合特性、农艺性状及干物质量的差异.[结果]N3处理下青贮玉米的SPAD相较于N0提高17.56%;N3处理下净光合速率、水分利用率分别提高 17.42%、36.56%,N4处理蒸腾速率和气孔导度分别比N0高50.00%、49.14%,胞间二氧化碳N2处理比N0高42.96%,农艺性状及干物质量均以N3处理最高,相比N0株高、基径、叶面积指数、干物质量分别提高10.60%、18.18%、41.05%、34.59%.[结论]河西灌区施氮量280 kg/hm2能够提高抽雄期玉米光合特性、农艺性状及干物质量.
Abstract
[Objective]To explore the effects of nitrogen application on daily photosynthetic variation,agronomic traits,dry matter quality of silage maize in the irrigation area of Hexi Corridor,and to identify the optimal nitrogen ap-plication rate.[Method]Field experiments were carried out in the irrigation area of Hexi corridor in 2022 usingsilage maize Jinling No.67 as the research object.,Five nitrogen application levels were tested;N0(0 kg/hm2),N1(218 kg/hm2),N2(249 kg/hm2),N3(280 kg/hm2),N4(311k g/hm2)We analyzed the impact of different nitrogen appli-cation levels on the relative chlorophyll content(SPAD),photosynthetic characteristics,agronomic traits and dry mat-ter content of leaves during the male floweringstage of silage maize.[Result]Compared with N0,the SPAD of si-lage maize under N3 treatment increased by 17.56%.Under the N3 treatment,the net photosynthetic rate and water utilization rate increased by 17.42%and 36.56%,respectively.The transpiration rate and stomatal conductance un-der N4 treatment were 50.00%and 49.14%higher than N0,while intercellular carbon dioxide levels under N2 treat-ment were 42.96%higher than N0.Agronomic traits and dry matter quality were the highest under N3 treatment,with plant height,basal diameter,leaf area index and dry matter quality were increased by 10.60%,18.18%,41.05%and 34.59%respectively,compared toN0.[Conclusion]A nitrogen application rate of 280 kg/hm2 in Hexi irrigation area significantly enhances the photosynthetic characteristics,agronomic traits and dry matter quality of maize during the male floweringstage.
维普
万方数据