再生稻种植的气候适宜性研究

Climate suitability for ratoon rice planting

为探索再生稻在上海市松江区种植的气候适宜性,于2018年、2019年对再生稻品种‘松早香1号’进行试验,并结合上海市松江区气象观测站1999—2019年气象资料进行分析。结果表明:再生稻两茬总产量明显高于一季稻;‘松早香1号’作为再生稻栽培,从播种到后茬齐穗需要10℃以上有效积温2640℃·d;再生稻前茬收割较晚时,后茬开花期遭遇低温冷害的风险较大。后茬无效穗的形成与开花期最低气温关系密切,在低温来临前尚未开花的颖花一般都不能受精,低温冷害指标为日最低气温≤13℃或连续2 d≤14℃。在露地育秧、4月10日播种的情况下,后茬齐穗期遭受低温冷害的风险较高;如果采取塑料大棚育秧,达到80%安全齐穗保证率的安全播种期为4月1日。研究结果为再生稻在上海地区推广提供技术依据。

In order to study the climate suitability for ratoon rice,field experiment was carried out in Songjiang District of Shanghai from 2018 to 2019 with the ratoon rice variety of‘Songzaoxiang 1’,combined with the meteorological data from 1999 to 2019 in Songjiang District.The results showed that the total output of two ratoon rice stubbles were higher than that of single-season rice;And planting as ratoon rice,‘Songzaoxiang 1’required 2640℃·d active accumulated temperature≥10℃from sowing to safe full heading time.When the firstcrop of ratoon rice was harvested late,the risk of cold damage in the flowering stage of the next crop was higher.Moreover,the formation of aftercrop ineffective spike was closely related to the minimum temperature in the flowering period.Taking the condition that 2 consecutive days with lowest temperature below 14℃or lowest temperature below 13℃as chilling damage standard,spikelets which had not bloomed were generally not fertile before the onset of low temperature.In the case of bare land seedling,there would be higher risk of encountering chilling damage during aftercrop full heading stage for case like sowing on April 10th;if seedling with greenhouse,the safe sowing date for 80%of the guaranteed rate of complete panicle was April 1st.The results provide a technical basis for the extension of ratoon rice in Shanghai.