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一、为什么要进行提纯复壮? 甘薯为我区主要粮食作物之一,历年栽培面积130—150万亩。目前生产上用种百分之九十左右为胜利百号,但由于长期以来忽视留种工作,致使良种特性发生变异和退化,其严重程度据调查已达百分之八十至九十以上,甚至不少地区已很难找到原种。退化的比原种类型平均减产二成左右,切干率与淀粉含量降低百分之一至二。因此,对新推广良种如不注意留种工作,长此下去,也会造成同样结果。优种为什么会退化变劣?因为任何事物都是在不断发展变化的。甘薯良种也是如此,它虽是无性繁殖作物,比其它种籽作物变异性较小,但所有甘薯品种确都是杂种后
First, why should purify rejuvenate? Sweet potato is one of the main food crops in our region, over the years cultivated area of 130-150 acres. At present, about 90% of the products used for production are Shengli Hundred, but as the long-term neglect of the remaining kinds of work has caused the variation and deterioration of the characteristics of the elite varieties, the severity has already reached 80% to 90% Even in many areas it is hard to find the original species. Degradation than the original type of about 20% of the average cut, cutting and starch content decreased by 1 to 2 percent. Therefore, if we do not pay attention to the new kinds of seed for the newly promoted seeds, the same result will be caused if the animals continue to grow for a long time to come. Why does the elite deteriorate? Because everything is evolving. The same is true of sweet potato varieties, although it is asexual reproduction of crops, less than other varieties of crop variability, but all sweet potato varieties are indeed hybrids