内蒙古地区玉米低温冷害动态监测指标的建立

利用内蒙古主要玉米种植区36个站点1981-2010年的气象和玉米产量资料,10个农业气象观测站的发育期资料及玉米品比试验资料,分析了5种熟性玉米品种正常年份的热量需求,确定各品种主要发育期平均出现日期和标准活动积温下限.采用相对活动积温距平（TXJ）计算方法,统计了近30a各站主要发育期的TXJ,以TXJ负值和减产率的关联性为基础,确定各品种一般低温冷害和严重低温冷害的TXJ阈值监测指标. 36个站近30a的回代检验和24个典型年分析表明：冷害发生与减产的吻合率随生育进程呈增加的趋势,在吐丝-乳熟期最高,达到69％,乳熟-成熟期次之,为67.1％；晚熟品种吻合率高于偏早熟品种,严重冷害（76.6％）高于一般冷害（57.2％）；典型年判断准确率平均为95.8％,吐丝期以后达到100％;吐丝-乳熟期是冷害发生最敏感的时期.该指标综合反映了生长季各阶段低温累积效应和高温补偿效益,农学和生物学意义明确,可在内蒙古低温冷害监测业务中推广应用.

Study on Dynamic Monitoring Index of Maize Chilling Damage in Inner Mongolia

Based on meteorological data and maize yield data of 36 meteorological stations, and maize growth and development period data of different varieties of 10 agro-meteorological stations in Inner Mongolia from 1981 to 2010, the heat requirement of the 5 varieties of maize in normal years was analyzed, and the average dates of the growth and development period of different varieties and the limitation of active accumulated temperature was determined. By using the expressions of relative active accumulated temperature distance （Txj）, the Txj of the different developmental period of the 30 years on stations was calculated, and the Txj index of the slight and serious degree chilling damage was determined, based on the relationship between the negative distance and yield reduction rate. The analysis results of 24 typical years and 36 stations in 30 years showed that the highest agreement between chilling damage years and yield reduction was in spinning-milky stage （69%）, followed by milky-maturity stage （67.1%）. Late-maturing varieties were higher than early maturing varieties and serious chilling damag 100% reflect during damage years （76. 6% ） were higher than slight chilling e years （57.2%）. In typical years, the average accuracy of the judgment was 95.8%, which could increase to after the spinning stage. Spinning-milky was the most sensitive period to the chilling damage. The index could the cumulative effects of low-temperature and compensation benefit of high-temperature in different growth stages the whole growth season, and could be applied in chilling damage monitoring service in Inner Mongolia.