播期对夏玉米生长状况、光合速率及产量要素的影响

Effects of Sowing Date on Growth Status,Photosynthetic Rate and Yield Factors of Summer Maize

[目的]研究不同播期对夏玉米生育期、高度、茎粗、叶面积指数与光合速率、干物质积累、产量要素的影响。[方法]于2019年开展为期1年的分播期试验,供试玉米品种为郑单958。采用裂区试验,设4个播期处理,分别在5月31日(B1)、6月10日(B2)、6月20日(B3)、6月30日(B4)播种。每处理设4个重复。[结果]晚播处理前期发育期进程加快,后期发育期天数差异不明显,最终造成随着播期的推迟,发育期天数逐渐缩短并且B4处理在灌浆后期日均温度低于灌浆所需温度而停止灌浆,导致玉米无法完全成熟;随着播期推迟不仅增加了倒伏的风险和乳熟期光合速率逐渐降低,同时加上随着播期推迟果穗变短变细,从而影响干物重积累,最终导致产量降低。[结论]考虑鹤壁地区常年小麦收获期在6月2—10日,在6月2—15日播种对玉米产量的提高将更有利。

[Objective]The aim was to study the effects of different sowing dates on growth period,height stem diameter,leaf area index,photosynthetic rate,dry matter accumulation and yield factors of summer maize.[Method]In 2019,a one-year split sowing date test was carried out with Zhengdan 958 as the tested maize variety.The test adopted a split-plot test with four sowing date treatments,which were sown on May 31(B1),June 10(B2),June 20(B3)and June 30(B4).Each treatment had 4 replicates.[Result]The process of early development stage of late sowing treatment was accelerated,and the difference of days in late development stage was not obvious.Finally,with the delay of sowing date,the days of development stage were gradually shortened,and the daily average temperature of B4 treatment in the late filling stage was lower than the temperature required for filling,resulting in the failure of maize to fully mature.With the delay of sowing date,not only the risk of lodging and the gradual decrease of photosynthetic rate at milk ripening stage were increased,but also the ear became shorter and thinner with the delay of sowing date,which affected the accumulation of dry matter weight and eventually led to the decrease of yield.[Conclusion]Considering that the harvest period of perennial wheat in Hebi area is from June 2 to 10,sowing from June 2 to 15 will be more beneficial to the increase of maize yield.