南宁地处广西南部,气候温暖,夏长冬短,属亚热带气候,自然条件优越,历史上为双季稻作区。但由于春秋季受北方冷空气的影响,早稻播种育秧时容易出现低温阴雨天气,造成烂秧;晚稻抽穗扬花时又易受到寒露风危害,空秕率增加,千粒重降低,产量不稳定。以连续3天以上日平均气温≤12℃作为早稻 Nanning is located in southern Guangxi, the climate is warm, summer and winter is short, is a subtropical climate, superior natural conditions, the history of double cropping area. However, due to the influence of the cold air in northern China during spring and autumn, low temperature and rainy weather tends to occur during sowing and planting of early rice, resulting in rotten seedlings. Late heading and flowering are vulnerable to cold and wind devastation, increasing the emptying rate and reducing the grain yield and yield instability. To the average daily temperature of more than 3 days ≤ 12 ℃ as early rice