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近年来,棉花病害成为世界棉花产量进一步提高的主要障碍之一。据美国统计,棉花因遭受病害平均每年减产13—15％。其中以黄萎病危害最重,平均每年减产3—4％(约八万吨皮棉),因枯萎病减产0.8—1％,因角斑病减产1—2.5％,因根腐病减产1—2％,还有一些其它病害使棉花减产也很重。国外棉花育种工作者多年来研究表明,采用棉花普通品种杂交,很不易得到抗多种病害
In recent years, cotton diseases have become one of the main obstacles to further increase of world cotton output. According to statistics from the United States, the average annual loss of cotton from diseases is 13-15%. Among them, Verticillium wilt is most harmful, with an average annual reduction of 3-4% (about 80,000 tons of lint), a decrease of 0.8-1% due to fusarium wilt, a 1-2.5% decrease of angular leaf spot and a decrease of 1- 2%, there are some other diseases so that cotton yield is also heavy. Foreign cotton breeders over the years of research shows that the use of ordinary varieties of cotton cross, it is not easy to get a variety of diseases