玉米群体结构对年际间气象因子变化的反应

以晚熟稀植品种丹玉39和中晚熟密植品种郑单958为试材，通过5年的定点栽培试验，对玉米群体结构与年际间气象因子变化的关系进行研究。结果表明：玉米群体结构对年际间气象因子变化的反应不同，并导致不同年份的适宜密度和适宜密度范围发生变化，最终对产量造成影响。降水量及时间分布是影响群体结构的最主要因子，其次为日照时数。受影响最大的是叶面积指数，其次依次为叶向值、株高、透光率。6月下旬的降水量对LAI影响较大；7月上旬日照时数与叶向值密切相关；株高形成期的降水量是影响株高变化的根本原因。

Response of population structure of maize to annual changes of meteorological factors

The relationship between annual changes of meteorological factors and population structure of maize were studied through the 5-year experiment with Danyu 39 (late maturing variety) and Zhengdan 958 (mid-late maturing variety) as test materials. The results indicated that the annual changes of meteorological factors had a significant effect on the population structure of maize and caused the changes of optimum density and suitable density range of different maize hybrids which affected the yield finally. Precipitation and its temporal distribution were the most important factors affecting population structure, followed by the sunshine duration. Leaf area index (LAI) was most heavily affected, followed by leaflet orientation value (LOV), plant height and light transmittance. LAI was influenced greatly by the precipitation in the last ten-day of June; LOV was closely related to the sunshine duration in the first ten-day of July; and plant height was fundamentally affected by the precipitation in formative period of plant height.