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近些年梨树病虫害发生越来越严重,喷药次数越来越多、用药浓度越来越高,但防治效果却越来越差,究其原因,其中重要的一点是未抓住防治关键期。梨树各种病虫害的发生是随着梨树物候期而变化的,梨树落花后,也正是多种病虫害初发生期,所以该期也是多数梨树病虫害防治关键期。做好该期病虫害防治工作,可大大减轻全年病虫害防治任务,减少喷药次数,不但节省成本,还有利于无公害果品生产。对梨树生产危害较大的主要病虫
In recent years, Pear tree pests and diseases are more serious, more and more spraying, the drug concentration is getting higher and higher, but the control effect is getting worse, the reason, one of the important point is not to seize the key to prevention and control period. The occurrence of various pests and diseases of pears varies with the phenophase of pears. After the pears fall, it is also the beginning of many diseases and pests. Therefore, this is also the key period for the prevention and control of most pear pests. Do a good job in the period of pest control work, can greatly reduce the pest and disease control tasks throughout the year, reducing the number of spraying, not only save costs, but also conducive to pollution-free fruit production. Pear trees produce greater harm to the major pests