每一个水稻品种(组合)在生产上的应用,都会随着时间的延长,抗病性逐年减弱,种性退化,最终被新的优良品种(组合)所代替。为此,必须及时地选育或引进新的更好的品种(组合)。通过中间试验进行定期更新更换。我省自1980年以来。共审定(认定)通过了自己选育或引进的水稻品种(组合)50多个,水稻主栽品种共进行了2～3次大面积的更新更换,为我省粮食的增产作出巨大的贡献。但我省在水 Each rice variety (combination) in the production of applications, will over time, disease resistance weakened year by year, species degradation, eventually replaced by new varieties (combination). To this end, new and better varieties (combinations) must be bred or introduced in a timely manner. Through the intermediate test regularly updated replacement. My province since 1980. A total of more than 50 rice varieties (combinations) that were selected or introduced by themselves were examined and approved (confirmed). Major rice varieties underwent 2 to 3 large-scale replacement and replacement, contributing greatly to the grain yield increase in our province. But my province is in the water