Ma Shu Qing, Liu Xiao Hang, Deng Kui Cai, Quan Hu Jie, Tong Li Yuan, Xi Zhu Xiang, Chai Qing Rong, Yang Jun
Meteorological Observatory of Jilin Province, Changchun 130062, China.
Yanbian Agrometeorological Experiment Station, Yanbian 133001, Jilin, China.
Ying Yong Sheng Tai Xue Bao. 2018 Jan;29(1):125-132. doi: 10.13287/j.1001-9332.201801.036.
A low temperature treatment in rice booting key period was executed on the north slope of Changbai Mountains to construct the impact model of low temperature on rice shell rate, and to reveal the effects of low temperature at different stages of rice young panicle on seed setting. The results showed that effects of low temperature in the young ear formation stage on rice shell rate generally followed the logarithmic function, the lower the temperature was, the greater the temperature influence coefficient was, and the longer the low temperature duration was, the higher rice shell rate was. The seed setting rate was most sensitive to low temperature in the middle time of booting stage (the period from formation to meiosis of the pollen mother cell), followed by the early and later stages. During the booting stage, with 1 ℃ decrease of daily temperature under 2-, 3- and 5-day low temperature treatments, the shell rate increased by 0.5, 1.7 and 4.3 percentage, respectively, and with 1 ℃ decrease of daily minimum temperature, the shell rate increased by 0.4,1.8 and 4.5 percentage, respectively. The impact of 2-day low temperature was smaller than that of 3 days or more. The impact of accumulative cold-temperature on the shell rate followed exponential function. In the range of harmful low temperature, rice shell rate increased about 8.5 percentage with the accumulative cold-temperature increasing 10 ℃·d. When the 3 days average temperature dropped to 21.6, 18.0 and 15.0 ℃, or the 5 days average temperature dropped to 22.0, 20.4 and 18.5 ℃, or the accumulative cold-temperature was more than 8, 19, 26 ℃·d, the light, moderate and severe booting stage chilling injury would occur, respectively. In Northeast China, low temperature within 2 d in rice booting stage might not cause moderate and severe chilling injury.
在长白山北坡水稻孕穗关键期进行低温处理，构建低温对水稻空壳率的影响模型，揭示水稻幼穗不同阶段低温对结实率的影响。结果表明，幼穗形成期低温对水稻空壳率的影响总体呈对数函数关系，温度越低，温度影响系数越大，低温持续时间越长，空壳率越高。结实率在孕穗期中期（花粉母细胞形成至减数分裂期）对低温最敏感，其次是前期和后期。孕穗期，在2天、3天和5天低温处理下，日平均气温每降低1℃，空壳率分别增加0.5、1.7和4.3个百分点；日最低气温每降低1℃，空壳率分别增加0.4、1.8和4.5个百分点。2天低温的影响小于3天及以上。累积低温对空壳率的影响呈指数函数关系。在有害低温范围内，累积低温每增加10℃·d，水稻空壳率增加约8.5个百分点。当3天平均气温降至21.6、18.0和15.0℃，或5天平均气温降至22.0、20.4和18.5℃，或累积低温超过8、19、26℃·d时，分别会发生轻、中、重度孕穗期冷害。在中国东北地区，水稻孕穗期2天内的低温可能不会造成中度和重度冷害。
