喀什地区复播玉米品种生态适应性研究

摘要

【目的】为南疆喀什地区“一年多熟”周年超吨粮﹑麦后复播玉米适宜品种筛选提供理论和技术支撑。【方法】对4个玉米品种新玉29号﹑浚单20号﹑京单28号﹑新玉35号,设置3个不同种植密度进行麦后种植,研究复播玉米生育进程﹑群体叶面积指数(LAI)﹑干物质积累与分配﹑植株形态及产量结构对密植的响应变化,揭示玉米生育期的光﹑温生态因子与产量及其结构的关系。【结果】随着种植密度增加,复播玉米生育期相应推后2~6 d,早熟品种前期发育快﹑吐丝早,叶面积指数高﹑干物质积累与转运多,有利于玉米籽粒正常成熟和高产形成。种植密度9.0 x 104~9.75 x 104株∕hm2条件下,新玉35号和新玉29号均能发挥增密﹑增产的丰产潜力。复播玉米在拔节—成熟期间光辐射强度﹑日照时数和≥10℃有效积温与产量形成密切相关。【结论】新玉35号成熟期早,植株高度适宜。在密植条件下,叶面积指数增长快,干物质积累多,增产效益显著,可推荐作为麦后复播玉米的理想品种。同时,拔节—成熟期光照充足﹑日照时间长﹑有效积温高有利于产量提高。%Objective] The purpose of this study is to provide scientific theoretical basis and technical guidance for selecting the summer maize varieties which might make possible the planting model of wheat∕maize annual yield over 1,000 kg per mu in Kashgar region of Southern Xinjiang.[Method]The four maize varieties (Xinyu 29,Jundan 20,Jingdan 28 and Xinyu 35) of preliminary selection were planted after wheat harvest under plastic mulching condition and three different planting densities.Effect of different planting den_sities on growth process,leaf area index (LAI),dry matter accumulation and distribution,plant morphology and yield of multiple cropping maize were researched in order to reveal the correlation between ecological factors (light and temperature), yield and yield components.[ Result] With the increase of planting density, the growth period of the summer maize was delayed 2 —6 days.The vegetative growth and silking of the early ma_turing varieties with higher LAI and better dry matter accumulation and distribution developed faster than other varieties,which were beneficial for grain maturity and high yield formation.The Xinyu 35 and Xinyu 29 had higher yield potential under the planting density of 9.0 x 104 —9.75 x 104 plants∕hm2.The yield formation was significantly correlated with light radiation (sunshine duration) and effective temperature above 10℃ during the periods from jointing to maturity.[Conclusion] The maize variety of Xinyu 35 showed the character of ear_ly maturity,suitable height,fast increasing LAI and higher dry matter accumulation,all of which could signifi_cantly increase yield efficiency.Therefore,the Xinyu 35 was regarded as the suitable summer maize variety in Kashgar.During the periods of jointing and maturity of the summer maize,adequate light radiation,that is lon_ger sunshine duration and higher effective temperature were helpful to improve maize yield potential.