棉花病虫发生与阶段防治

Occurrence and Staged Control of Pests and Diseases in Cotton Fields

棉花产量的２０～４０％取决于病虫害发生之轻重，拟定正确的病虫防治对策和措施是提高防治水平，增加植棉效益的关键。棉花生育期与病虫发生规律有其相对应的阶段性。棉花播种前和苗期应以防病除草为主，确保壮苗早发；蕾花期要充分发挥自然天敌的控害作用和棉株自身的耐害性与补偿功能，尽可能控制棉田用药，花铃期抓主要害虫主害代集中施药，兼治其他害虫，保铃保产。这就是“抓两头，控中间”的药治对策。棉田分阶段防病治虫，实质是科学用药。包括针对性农药品种的选择及使用次数，把握用药的火候和范围，运用先进的施药器械和方法，提高着药部位的准确性及质量等等，都必须认真对待，才能减少投入，提高防效，延缓抗药性产生。

The insects and fungi of cotton can cause damage of yield for 20￣40%. The key to increasing productivity of cooton is making up a suitable strategy of pest control. The accurrence of pests is corresponding to growth stages of cotton.Before and after sowing and seedling age,it is necessary to control weeds in order to get earlier emergence and healthy seedling of cotton. During the flower bud period, taking care of natural enemy,giving full play of endurance,compensation effect of plants and spraying as less as pesticides are important.In the cotton boll stage, it is also important to pay more attention to control the major pests and suppress minor pests at the same time for guaranting good harvest. In the other hand , selecting of pesticide products,application times, suitable spray equipments and accurative operation are also important to control pests.