调亏灌溉下春玉米水氮耦合效应试验研究

为探讨寒地黑土区节水型高产玉米生产技术,以玉米品种九龙12为试验材料,采用正交试验方法,通过春玉米筒测试验,在3种施氮水平条件下,研究了苗期、拔节期、抽雄期3个水分亏缺水平对玉米生长发育指标和产量影响的耦合效应。结果表明:在不同调亏时期,植株经复水灌溉后有不同程度的补偿性生长。施氮量决定不同调亏时期的水分亏缺程度,苗期供应水分过高、氮肥过大会减少植株茎粗;拔节期水分亏缺时,植株茎粗受施氮量的影响较大,水分亏缺程度越重,氮肥施用量就应随之增高。当目标产量大于13 500kg·hm-2时,在95%的置信区间,苗期、拔节期和抽雄期的水分亏缺阈值分别为田间持水量的48%~66%、72%~84%和66%~81%,施纯氮肥160kg·hm-2。

Study on Water-nitrogen Coupling Effect of Spring Maize under Regulated Deficit Irrigation

In order to explore the production technology of water-saving and high yield for cold area ,taking maize variety of Jiulong 12 as test material ,through orthogonal test ,water-nitogen coupling effects of three lev-els of water deficit including seeding stage ,jointing stage and tasseling stage on growth indexes and yield were studied under three levels of nitrogen fertilizer by pot experiments of spring maize .The results showed that the height of maize had different compensatory growth after re-watering under different periods of regulated deficit irrigation .The degree of water deficit was determined by nitrogen rate .The stem diameter decreased with high water and nitrogen at seedling stage .When the target yield was above 13 500 kg·hm^-2 and the confidence inter-val was 95% ,the threshold value of water deficit in seeding stage ,jointing stage and tasseling stage were 48% ~66% ,72% ~84% and 66% ~81% respectively than field capacity ,and nitrogen rate was 160 kg·hm^-2 .