Green leafhopperTwo species of green leafhoppers (GLH) can spread tungro: Nephotettix malayanus and Nephotettix virescens. What it doesGreen leafhoppers are the most common leafhoppers in rice fields and are primarily critical because they spread the viral disease tungro. Both nymphs and adults feed by extracting plant sap with their needle-shaped mouthparts. Why and where it occursStaggered planting encourages population growth of GLH. Green leafhoppers are common in rainfed and irrigated wetland environments. They are not prevalent in upland rice. Both the nymphs and adults feed on the dorsal surface of the leaf blades rather than the ventral surface. They prefer to feed on the lateral leaves rather than the leaf sheaths and the middle leaves. They also prefer rice plants that have been fertilized with large amount of nitrogen. How to identifyRice fields infested by GLH can have tungro, yellow dwarf, yellow-orange leaf, and transitory yellowing diseases. Symptoms include:
Tungro infected crops may sometimes be confused with nitrogen deficiency or iron toxicity or acid soils. To confirm the cause of the problem, check for virus infected plants in the fields, and the presence of the insect:
Why is it importantGreen leafhoppers are important pests. They are vectors of viral diseases such as tungro, yellow dwarf, yellow-orange leaf, transitory yellowing, and dwarf. How to manage
In areas without tungro source, insecticides are not needed, avoid spraying of insecticide (it is often unable to prevent or reduce tungro infections). Encourage biological control agents: small wasps (parasitize the eggs), mirid bug; strepsipterans, small wasps, pipunculid flies, and nematodes (parasitize both the nymphs and adults), aquatic veliid bugs, nabid bugs, empid flies, damselflies, dragonflies, and spiders, fungal pathogen (attacks both nymph and adult).
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