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从 198 1年到 2 0 0 0年 ,湖南省早稻品种 (含杂交稻组合 )的发展呈现出如下趋势 :中熟当家 ,迟熟比例下降 ,早熟比例先降后升 ,杂交早稻发展迅猛 ;拔尖品种减少 ,主栽品种主导作用降低 ;品种数量大量增加 ,60 %以上品种年播种面积低于 6 7khm2 。分析了产生这些现象的原因 ,并对今后早稻育种方向进行了探讨
From 1981 to 2000, the development of early rice varieties (including hybrid rice combinations) in Hunan Province showed the following trends: the proportion of late ripening decreased, the proportion of early maturity decreased first and then rose, the hybrid early rice developed rapidly; top-notch Varieties decreased, the dominant varieties of cultivars decreased; varieties increased significantly, more than 60% of the annual sown area less than 6 7khm2. The reasons for these phenomena were analyzed and the future direction of early rice breeding was discussed