To prevent diseases and insect pests, it is more important to prevent drug pests. How to prevent the drug damage of fruit trees?

In rural areas, some fruit farmers lack common sense of drug use, which results in drug damage when spraying pesticides on fruit trees, which not only burns a large number of leaves and tender shoots of fruit trees, affects the growth of fruit trees, but also produces drug rust on the fruit surface and reduces the value of fruit products. Fruit trees should prevent not only diseases and insect pests, but also drug pests.

Fruit trees

First, do not use pesticides blindly. According to the fruit tree diseases and insect pests, the symptomatic use of medicine, the characteristics of fruit tree diseases and insect pests are different, the resistance to pesticides is also different, blindly following the trend is bound to cause fruit tree drug damage. For example, drupes and kiwifruit are sensitive to trichlorfon and dichlorvos; peach trees are sensitive to phosphoramines; kiwifruit is sensitive to omethoate and dimethoate; Dangshan pears in young fruit stage are also sensitive to Bordeaux liquid and Fuxing; the young tissues of peaches, grapes and plums are also sensitive to multi-dose Bordeaux liquid, if sprayed blindly, it will cause drug damage to fruit trees.

Second, the concentration of the liquid should not be too high. The solution shall be prepared according to the concentration range on the trademark. Emulsion, water pesticide bottle cap quantity, powder pesticide matchbox quantity, these rough preparation methods are not accurate. Low concentration is ineffective for the treatment of diseases and insect pests. If the concentration is high, there will be drug damage to fruit trees.

Third, avoid mismatch of pesticides. Some can be mixed with spray, but some pesticides can not be mixed; some acidic and alkaline mix, reducing the efficacy, resulting in sediment, not easy to spray. Some pesticides are easy to cause drug damage after spraying on fruit trees. For example, the mixture of Bordeaux liquid and stone sulfur mixture will increase water-soluble copper, which is most likely to cause drug damage to fruit trees after spraying.

Fourth, Bordeaux liquid should not be sprayed before rain. Usually listen to the weather forecast before spraying pesticides. If it rains on that day, do not spray, especially before the rain, spray Bordeaux liquid, the lime on the fruit surface is washed away by Rain Water during the rainfall, leaving copper sulfate ions to stimulate the skin of the young fruit, resulting in drug damage, the formation of striped apples, the loss of commercial value.

Fifth, avoid spraying in dry and hot weather. In general, the suitable temperature for pesticides is 20 ~ 30 degrees, and the highest temperature can not exceed 32 degrees. Because most pesticides are sprayed in too dry and high temperature weather, the water evaporates quickly, the pesticide concentration increases, and the fruit trees absorb quickly, metabolize strongly and reduce their resistance, so they are prone to drug injury. therefore, the safe and effective use time of pesticides is before 10:00 in the morning and after 3 o'clock in the afternoon. However, some pesticides such as stone-sulfur mixture are excepted, which are more lethal to diseases and insect pests at high temperature.