播期对玉米籽粒灌浆特性、产量及水分利用效率的影响

Effects of Different Sowing Dates on Grain Filling Characteristics,Yield and Water Use Efficiency of Maize

为探明河北低平原区玉米一熟种植模式下的适宜播期,以郑单958为供试品种,设置5月5日、5月20日、6月5日和6月20日共4个播期处理,研究了仅灌溉出苗水条件下不同播期处理对玉米株高、叶面积指数、净光合速率、灌浆特性、产量和水分利用效率的影响。结果表明:吐丝期玉米株高和叶面积指数随着播期推迟呈现先增大后减小的趋势,6月5日处理最大,5月5日处理最小。授粉后30 d,6月5日、5月20日处理的净光合速率较高,5月5日、6月20日处理的净光合速率较低。Logistic曲线能较好地实现玉米籽粒灌浆过程模拟,6月5日处理平均灌浆速率最大,最大灌浆速率和速增期持续时间较高,促使其百粒重最大,穗粒数较多,产量显著高于其他处理。处理间玉米耗水量差异不大,水分利用效率随播期延迟先增大后减小,6月5日处理的水分利用效率最高。河北低平原区玉米适期播种(6月5日)有利于植株生长、产量形成和水分利用效率的提高。

The research aims at investigating the suitable maize sowing date under the maize mono-cropping system in the Hebei Low Plains.Zhengdan 958 is used in the field experiment with four sowing dates(May 5,May 20,June 5 and June 20).The plant height,leaf area in⁃dex,net photosynthetic rate,grout characteristics,yield and water use efficiency of maize are studied.The results show that the plant height and leaf area index of maize increase first and then decrease with the delay of the sowing date,with June 5treatment being the maximum and May 5 treatment being the minimum.After pollination,the net photosynthetic rate of June 5 and May 20 treatment is higher,and the net pho⁃tosynthetic rate of May 5 and June 20 treatment is lower.Logistic curve can well simulate the corn grain grouting process simulation,In June 5 treatment,the average filling rate is the highest,the maximum grouting rate and the duration of the rate-increasing period are higher,which promotes the maximum 100-grain weight and the number of grains per ear.There is little difference in water consumption of maize be⁃tween treatments,and the WUE first increases and then decreases with the delay of sowing date.The water use efficiency of June 5 treatment is the highest.Planting maize in suitable time(June 5)in the Hebei Low Plains is beneficial to plant growth,yield formation and water use efficiency.