基于障碍型冷害损失评估模型推算东北水稻无障碍型冷害终日

利用东北地区35个气象站1981-2012年逐日气象资料和水稻生育期数据,借助水稻障碍型冷害损失评估模型,模拟不同耐寒性粳稻幼穗分化期后逐日空壳率的变化,并以空壳率在80%保证率下不超过生理空壳率(7.62%)的终日作为无障碍型冷害终日(NSCI)。结果显示,东北地区粳稻NSCI大体呈纬向分布规律,随纬度增加而提前;黑龙江省耐寒性较弱、耐寒性较强和耐寒性强3种类型水稻的NSCI分别为7月14、17和22日,吉林省分别为7月18、21和25日,辽宁省分别为7月28日、8月4日和8月10日;近30a东北地区水稻NSCI年际波动较大,1981-2000年,NSCI没有明显变化趋势,以年际波动为主;2001-2012年,部分地区NSCI呈现显著延迟的趋势;NSCI前后30d及实际抽穗期前后30d低温冷害发生次数和强度的对比分析表明,参考模型推算的NSCI安排水稻生产,可以有效减轻水稻孕穗-灌浆结实期低温冷害的影响,说明由模型推算的不同耐寒性水稻安全齐穗期对保障东北水稻安全生产具有一定的参考价值。

Estimating the Last Date without Sterile-type Chilling Injury for Rice Based on a Model for Evaluation of Loss for Sterile-Type Chilling Injury in Northeast China

With the meteorological data and rice phenological records from 3 5 weather stations during 1981 to 2012,daily empty grain rates of rice were estimated by the model of evaluation and forecast of loss for sterile-type cool injury in rice plants.Three parameters were set to represent rice varieties with three types of cold tolerance.The date with empty grain rate estimated up to physiological empty grain rate (7.62％) was chosen as the last date without sterile-type cool injury for rice (NSCI).For each station,NSCI was estimated with 80％ of guarantee rate.The results showed NSCI advances with latitudes.The NSCIs for rice with weak,normal and strong cold tolerance in Heilongjiang Province were on 14,17 and 22 July respectively,while in Jilin Province they were on 18,21 and 25 July respectively,and on July 28th,August 4th,August 10th,respectively in Liaoning Province.In recent 30 years,the temporal variation of NSCI in northeast China was evident,which showed a deferred trend during 2001 to 2012 in some area of northeast China.Comparison of chilling injuries during 30 days before and after NSCIs with that during 30 days before and after observed heading dates showed that the method used in this study is able to estimate NSCIs for rice in northeast China with enough accuracy,which can effectively help agricultural management prevent and mitigate chilling damage in rice key development stage.