早稻不同品种(组合)的耐寒性鉴定及其在农业生产中的应用

５２ 个品种（ 组合） 分期播种试验研究表明：不同品种（ 组合） 在不同时期播种，成苗率的变化规律并不一致；短期低温锻炼对许多品种（ 组合） 的成苗反而有好处．９４ 早８１６ 、浙９７１８ 、早优８ 号、赣早籼４１ 号、湘早籼１９ 号、湘早籼２４ 号等品种表现出较强的苗期耐寒性；大多数品种（ 组合） 的苗期耐寒性与孕穗期抗低温能力之间没有必然的相关性，但仍有９４ 早８１６ 、赣早籼４１ 号和浙９７１８ 三个品种在苗期和孕穗期表现出较强的抗低温能力；而Ｖ５６ 、９６ 早７７２ 和９５ 早鉴２５ 等品种（ 组合） ，在苗期抗寒力极差，但延迟在４ 月５ 日播种时产量反比早期播种的高，因此在生产应用中也是值得重视的品种（ 组合）．

Identification of the Cold-Resistance and Agricultural Application of Early-season Rice Varieties(Combinations)

In this experiment,52 cultivated varieties(combinations) of early season rice were sown by 5 different stages,the rate of seedlings/seeds for each one showed a different change mode with variable temperature at the sowing stage.Short term lower temperature may be favourable to increasing the rate of seedlings/seeds for many varieties(combinations).94 Zao 816,Ze 9718,Zaoyou 8,Ganzaoxian 41,Xiangzaoxian 19 and Xiangzaoxian 24 and so on showed the higher cold resistance at seedling stage.The cold resistance at seedling stage is not inevitably interrelated with the ability resistant to low temperature at booting stage for the great majority of varieties (combinations),but 94 zao 816,Ganzaoxian 41 and Ze 9718 still expressed the higher resistance to cold and low temperature at these two stages.Otherwise,V56,96 zao 772 and 95 zaojian 25 expressed the extremely poor cold resistance at seedling stage,but when they were sown at the 5th,April,they could obtain a more higher rate of seedlings/seeds and more higher grain yield than those sown at any other earlier stages.