温度对玉米生长和产量的影响

Effects of air temperature on maize growth and its yield

为了明确气温变化对玉米生长发育和产量的影响,建立玉米低温冷害监测和气象评估模式,在东北地区中部的榆树市进行了玉米分期播种试验。试验采用3个品种,设置早、中、晚3个播种期,进行玉米生长发育进程、叶面积指数、生物量、产量和温度等观测。结果表明:玉米的生长速率与温度密切相关,平均气温每升高1℃,出苗速率提升17%,营养生长速率提升5%;积温每增加100℃.d,玉米最大叶面积指数增加10%,最大生物量和产量增加8%;玉米生长发育期(日平均气温稳定>10℃期间)间平均气温降低0.7℃,或活动积温减少100℃.d,玉米成熟期将延迟7d,发生一般低温冷害,玉米单产减少8%;气温下降1℃,或积温减少140℃.d,生育期延迟10d,发生严重低温冷害,减产10%以上;在水分条件比较适宜的前提条件下,气候变暖对东北地区玉米单产提高是有利的。

Aimed to investigate the effects of air temperature on maize growth and its yield, and to establish a monitoring and evaluation model of maize chilling injury, a ＇ sowing by stages＇ field experiment with three maize varieties and conducted in Yushu City of Jilin Province. The three sowing dates （ early, medium, and late） was seedling growth rate, leaf area index （LAI） , biomass, and yield of maize, as well as the air temperature, were observed. The results showed that the growth rate of maize had a close correlation with air temperature. If the mean air temperature raised by 1 ℃, the seedling emergence rate and vegetative growth rate would increase by 17% and 5%, respectively; and if the cumulative temperature increased by 100 ℃ · d, the maximum LAI of maize would increase by about 10%, and the maximum biomass and per unit area yield of maize would increase by about 8%. If the mean air temperature in the growth period of maize （ the period with daily mean temperature 〉 10 ~C ） decreased by 0. 7 ~C, or the active cumulative temperature decreased by 100 ~C ~ d, the maturing stage of maize would be delayed 7 days, a moderate maize chilling injury would occur, and the biomass and yield of maize would decrease by about 8%. If the mean air temperature decreased by 1 ~C, or the cumulative temperature de- creased by 140 ~C ~ d, the growth stage of maize would be delayed 10 days, severe maize chill- ing injury would occur, and maize yield would decrease by 10% or more. Under the prerequisite of suitable soil moisture condition, climate warming would be beneficial to the increase of per unit area maize yield in Northeast China.