Nov 29, 2017 How to Control Plant Diseases and Insect Pests of Strawberry in Greenhouses in Winter
Wilt disease. After the leaves were damaged, the first purple spots appear small round, with the development of the disease, the spots expanded gradually, lesion edge darker color; lesions appear on the veins, the expansion rate faster than the leaves, it can spread to the entire leaf in the 7 ~ 10 days, then the transport of nutrients blocked, the whole leaf withered quickly. When the calyx is affected, decay occurs and lead to fruit can not be formed, it will be a great influence on production.
1, strengthen the Cultivation and management. The greenhouses used to grow strawberries, need to be ventilated constantly, to lower the humidity in the shed, and to water it in moderation, just to keep the soil moist. 2, Chemical control. At the beginning of the disease, 50% of the fumei zn 700 or 65% of dyson zinc can be used to control the disease. To prevent the contamination of the fruit, it should be applied after each fruit harvest.
Fruit rot disease. The disease can be on the disease in flowers, young fruit, fruit and ripe fruit. Early onset of young fruit, the dark brown spots appear on the fruit surface. After expanded gradually, the edge with brown spots will be slightly depressed in the middle. When the late severe, the fruit partially or completely decayed. More rain and snow, high humidity, the temperature is too low or too high, the incidence is serious. Especially when the soil humidity is high, the fruit near the ground is not only highly morbid, but also especially serious.
1, strengthen the cultivation and management. When the young fruit begins to form, whether open-field cultivation, or protected cultivation should be appropriate to control the amount of watering; rain and snow, planting around to start the drainage ditches, so that clear water discharge quickly to reduce soil moisture, can greatly reduce the incidence of close to the surface of the fruit. whenfound disease fruit should be promptly removed, with a field treatment, can not be thrown in the field. 2, chemical control. Initial onset, available 50% thiram 600 times, or 65% canister 400 times the spray, the control effect of up to 95%.
Strawberry leaf roller. The larvae crawl on leaf surface or dorsal and feed on the leaf. When the pest grows slightly, the green larva curls the leaves through the netting then eats the leaves. Once the leaves have been eaten, they will be transferred to the adjacent leaves then damage the leaves through the netting.
The prevention and treatment of strawberry leaf roller, when the larvae hatch at the beginning, appetite is small, weak drug resistance, hasn’t weave webs, this is the best time to spray. The pesticide with good effect are: 90% crystal trichlorfon 1200 times, or 25 enemy kill, kill 20% kill 2500 times the liquid, but also can be used 20% fenvalerate EC 2000 times the spray kill. If the prevention and treatment of more than 2 times, the drug should be used alternately, can improve anti-efficiency. To reduce the pollution of fruits, it is advisable to stop spraying after the fruit is harvested or 7 days before harvesting.