Abstract: In 2020, early rice was affected by cold in late spring, and large areas of serious rotten seedlings appeared in Zhejiang. Several investigation sites found that direct seeding rice is particularly serious, and the part of machine transplanting seedlings also died of seedlings due to low temperature and cold injury. Meteorological data analysis showed that, the average temperature in each ten-day of March 2020 was higher than that of previous years, and the temperature in early April was lower than that of previous years. The main reason for the phenomenon of large-scale rotten seed and dead seedlings, first, the late spring coldness temperatures on the 28-31 of late March are low and the daily temperature difference is small. The second, the temperature is high in the early March, mid-March and early late-March, low in the late period, and the temperature changes in the early and late periods are large. Early rice direct seeding prematurely, and the risk of temperature is high. Some early rice seedlings are not properly managed for seeding and seedlings, and the quality of substrates for mechanical transplanting seedlings and insulation equipment are not in place. In view of the existing problems and causes, the countermeasures of early rice to prevent dead seedlings from falling into the cold and rotten in the spring are proposed.

Key words: early rice, direct seeding, cold in late spring, rotten seed, dead seedling

摘要： 2020年早稻受“倒春寒”影响，浙江等地出现大面积严重的烂种死苗，几个调查点发现直播稻尤为严重，部分机插育秧也因低温冷害发病死苗。气象资料分析表明，2020年3月各旬平均气温较历年上升，4月上旬气温较历年下降。出现大面积烂种死苗现象主要原因有：一是3月28—31日气温低及日温差小；二是3月上中旬及下旬前期气温高，后期气温低，前期与后期气温变化大；三是早稻直播过早，受气温影响风险大，部分早稻机插育秧管理不到位，有的机插育秧基质质量差及保温条件差。针对存在的问题及成因，提出早稻防止“倒春寒”烂种死苗的对策措施。

关键词: 早稻, 直播, 倒春寒, 烂种, 烂秧