Three pests to control when growing beans in summer
Preventing "three pests" when growing beans in summer
(Agricultural Wealth Network) At a time of high temperatures and abundant rain, pole beans are in their peak growth stage, but pest damage is severe at this stage. If management cannot keep up, it very easily leads to reduced quality and lower yields. In terms of control measures, agricultural control should be the main approach, with equal emphasis on physical and chemical control.
I. Bean pod borer
For the bean pod borer, June to October each year is the larval damage period. Adults are phototactic, and eggs are laid singly on tender pods, flowers and leaf stalks. Newly hatched larvae bore into tender pods or flowers to feed, causing flowers and pods to drop. Older larvae bore into the bean pods to feed, and damaged bean pods often rot after rain. The larvae have the habit of hiding by day and emerging at night and are photophobic; during the day they hide in flowers, bean pods or curled leaves, excreting frass to block the bore holes. Apart from occasional activity on cloudy and rainy days and during the day, they generally begin crawling out from the bore holes in the evening and stop their activity by the next morning.
Control measures: 1. Remove fallen flowers and pods in the field, and pick off damaged curled leaves and bean pods to reduce the source of pests. 2. Set up black light lamps and use the phototactic habit of adults to trap and kill them. 3. For chemicals, choose 5% fipronil 2000-fold solution, 40% fenvalerate 6000-fold solution, 2.5% deltamethrin 3000-fold solution and other agents, spraying once every 10 days.
II. Leafminer
The larvae burrow into the leaves to cause damage, mining the leaf mesophyll and leaving only the upper and lower epidermis, forming winding tunnels and affecting plant growth. Leafminers mainly damage peas, kidney beans, cowpeas, cabbage, cauliflower, Chinese cabbage, rapeseed, radish, lettuce, tomato, eggplant, potato and so on.
Control measures: 1. Use sticky insect boards to trap and kill adults. 2. Adults mainly lay eggs on the underside of leaves, so when spraying liquid, focus on spraying the underside of leaves. When larval damage begins, choose insecticides with both systemic and contact action, such as 48% chlorpyrifos EC 800-1000-fold solution, and spray continuously 2-3 times.
III. Red spider mite
The red spider mite on beans is also called the bean leaf mite. August to September is the peak outbreak period. Adults and nymphs suck the tender leaves, and damaged leaves shrivel and easily drop. In the early stage of occurrence, the leaf surface loses green, turns white and then turns red, and the fine silk webs on the underside of the leaves can directly reveal the range and area of occurrence. Immediately after occurrence, use a sprayer to spray a pesticide encirclement ring, with a range slightly larger than the area of occurrence, then thoroughly spray the plants within the encirclement ring to prevent the spread of red spider mites.
Control measures: 1. Pay attention to pest monitoring. If a small amount of damage is found, promptly remove the damaged leaves and burn them. In dry weather, pay attention to timely irrigation and fertilization to promote plant growth and inhibit leaf mite proliferation. 2. Use selective acaricides for general control, before the pod-setting stage and after the bean pods are harvested, focusing on uniform spraying on the underside of leaves. You can spray 20% compound liuyangmycin EC 1000-fold solution, 1.8% abamectin EC 1500-2000-fold solution, 15% pyridaben EC 3000-fold solution, 20% amitraz EC 2000-fold solution and so on. Note to rotate the chemicals, and advocate the use of high-efficiency, low-toxicity biological pesticides.
I. Bean pod borer
For the bean pod borer, June to October each year is the larval damage period. Adults are phototactic, and eggs are laid singly on tender pods, flowers and leaf stalks. Newly hatched larvae bore into tender pods or flowers to feed, causing flowers and pods to drop. Older larvae bore into the bean pods to feed, and damaged bean pods often rot after rain. The larvae have the habit of hiding by day and emerging at night and are photophobic; during the day they hide in flowers, bean pods or curled leaves, excreting frass to block the bore holes. Apart from occasional activity on cloudy and rainy days and during the day, they generally begin crawling out from the bore holes in the evening and stop their activity by the next morning.
Control measures: 1. Remove fallen flowers and pods in the field, and pick off damaged curled leaves and bean pods to reduce the source of pests. 2. Set up black light lamps and use the phototactic habit of adults to trap and kill them. 3. For chemicals, choose 5% fipronil 2000-fold solution, 40% fenvalerate 6000-fold solution, 2.5% deltamethrin 3000-fold solution and other agents, spraying once every 10 days.
II. Leafminer
The larvae burrow into the leaves to cause damage, mining the leaf mesophyll and leaving only the upper and lower epidermis, forming winding tunnels and affecting plant growth. Leafminers mainly damage peas, kidney beans, cowpeas, cabbage, cauliflower, Chinese cabbage, rapeseed, radish, lettuce, tomato, eggplant, potato and so on.
Control measures: 1. Use sticky insect boards to trap and kill adults. 2. Adults mainly lay eggs on the underside of leaves, so when spraying liquid, focus on spraying the underside of leaves. When larval damage begins, choose insecticides with both systemic and contact action, such as 48% chlorpyrifos EC 800-1000-fold solution, and spray continuously 2-3 times.
III. Red spider mite
The red spider mite on beans is also called the bean leaf mite. August to September is the peak outbreak period. Adults and nymphs suck the tender leaves, and damaged leaves shrivel and easily drop. In the early stage of occurrence, the leaf surface loses green, turns white and then turns red, and the fine silk webs on the underside of the leaves can directly reveal the range and area of occurrence. Immediately after occurrence, use a sprayer to spray a pesticide encirclement ring, with a range slightly larger than the area of occurrence, then thoroughly spray the plants within the encirclement ring to prevent the spread of red spider mites.
Control measures: 1. Pay attention to pest monitoring. If a small amount of damage is found, promptly remove the damaged leaves and burn them. In dry weather, pay attention to timely irrigation and fertilization to promote plant growth and inhibit leaf mite proliferation. 2. Use selective acaricides for general control, before the pod-setting stage and after the bean pods are harvested, focusing on uniform spraying on the underside of leaves. You can spray 20% compound liuyangmycin EC 1000-fold solution, 1.8% abamectin EC 1500-2000-fold solution, 15% pyridaben EC 3000-fold solution, 20% amitraz EC 2000-fold solution and so on. Note to rotate the chemicals, and advocate the use of high-efficiency, low-toxicity biological pesticides.