1. Symptoms: aphid is a kind of insect pest that feeds on plant branches and leaves, and has a strong reproductive capacity. It is small and hard to be found, which is very harmful to water hyacinth. It will adhere to the leaves of the plant to absorb juice, which will cause the leaves to turn yellow and dry due to malnutrition. In serious cases, it will also cause the whole plant to die.
2. Prevention and control methods: once found, prevention and control shall be carried out immediately. The most direct way is to spray with insecticides.
1. Symptoms: the leaves of the affected plants will gradually turn yellow, then fade and turn white. If the spider does not appear on the plant for a long time, the whole plant may wither.
2. Control method: if there are few pests, they can be caught directly. If there are many pests, you can spray them with dimethoate emulsion. It can also be controlled with 10% of bendididaben EC. At the same time of prevention and control, spray water around the plant to increase humidity, and prevent the reproduction of pests.
1. Symptoms: leaf spot is a disease caused by fungi. When the disease occurs, there will be many irregular grayish brown patches on the leaves of Eichhornia crassipes. These patches will gradually spread to the roots and even cause the plant to die.
2. Prevention and treatment method: after the disease, spray 78% COBOL WP 500 times, 80% spray Ke WP 600-800 times or 50% carbendazim WP 500-1000 times. Spray once every 10 days, 2-3 times can improve the condition.
