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1 种植抗虫棉适时酌情防治虫害、科学化控抗虫棉不是无虫免药棉。抗虫棉的抗虫性是对一、二代棉铃虫具有强抗性,对三、四代棉铃虫具有较强抗性。由于棉株各个器官所含抗虫Bt基因不同,所以不同器官的抗虫性不同,嫩叶嫩尖抗性最强,叶片次之,棉铃最差。抗虫棉的杀虫特点是主棉的小幼虫咬食一些棉叶后中毒死亡,所以在田间不要一见卵量大就盲目喷药,也不要见虫多就视而不见。一般对一、二代棉铃虫可不防治,对三、四代棉铃虫百株幼虫数超过20头可用50%辛硫磷800倍液喷雾防治。在7月20日以后,人工摘除幼铃的干花里面藏有的幼虫带出田间,这是一项最经济有效的防虫方法。若发生蚜虫和红蜘蛛吋,可用40%氧化乐果800
1 planting insect-resistant cotton timely and appropriate pest control, the scientific control of insect-resistant cotton is not insecticide-free cotton. Insect-resistant cotton insect resistance is one or two generations of cotton bollworm has strong resistance to three or four generations of cotton bollworm has strong resistance. Because of the different insect-resistant Bt genes contained in different organs of cotton plant, the insect resistance of different organs is different, the tender leaf tender tip is strongest, the leaf blade second, and the boll is the worst. Insect-resistant cotton insecticidal characteristics of the main cotton larvae bite some cotton poisoning death, so do not see a large amount of blind spray in the field, do not see insects and turned a blind eye. Generally on the one or two generations of cotton bollworm can not control, on three or four generations of cotton bollworm 100 larvae more than 20 available 50% phoxim 800 times spray prevention and treatment. After July 20, the larvae hidden in the dried flowers of the young bell-eared bell are taken out of the field, which is one of the most economical and effective pest control methods. In the case of aphids and spider mites, available 40% omethoate 800