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陆地棉自从引入我国栽种以来,已有六十余年的历史,因为它的产量及品质都比中棉优越,所以近年以来已逐渐替代中棉而成为我国广大地区栽种的主要棉种,据1956年中央农业部估计,陆地棉已占全国棉田总面积的88%,但陆地棉品种的主要经济性状并不十分稳定,一个良好品种,栽种若干年后,往往呈现退化现象,如纤维变短,钤变小,种子变小,产量也随之减低,如何防止棉种退化,并进一步提高品种的优良特性,已成为棉花选种及良种繁育中一个迫切需要解决的问题。
Since the introduction of Upland cotton into our country has more than 60 years of history, because of its superiority in yield and quality than in cotton, so in recent years has gradually replaced the cotton and become the main species planted in vast areas of China, according to 1956 The Central Ministry of Agriculture estimates that upland cotton accounts for 88% of the total area of cotton fields in the country. However, the main economic traits of upland cotton varieties are not very stable. A good variety tends to degenerate after being planted for several years. For example,钤 smaller, smaller seeds, yield also will be reduced, how to prevent cotton degeneration, and further improve the excellent characteristics of varieties has become an urgent need to resolve cotton varieties and breeding.