Latin name | Common name | Symptoms | Confirmation | Problems with similar symptoms | Why and where it occurs | Causal agent | Host range | Life cycle | Mechanism of damage | When damage is important | Economic importance | Management principles | Selected references | Contributors
Green Leafhopper - adults (IRRI)
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Damage to plants |
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Signs |
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Factors favoring insect/pest development |
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Green leafhopper (GLH) |
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Nephotettix virescens (Distant) Nephotettix nigropictus (Stal) Nephotettix malayanus Ishihara et Kawase Nephotettix cincticeps (Uhler) |
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The presence of the insect and virus infected plants in the fields. |
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Tungro infected crops may sometimes be confused with nitrogen deficiency or iron toxicity or acid soils. |
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Staggered 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. |
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The adult leafhopper is slender and green. Its head is rounded or pointed with or without black bands. Its vertex is with or without an anterior black band and a submarginal black band extending beyond the ocelli to the inner margins of the eyes. The face is green. Its pronotum is smooth with or without a black anterior margin. A pair of black spots is either present or absent on the forewings. The insect is 4.2-4.3 mm.
Neonate nymph measures 0.9 mm long. It is transparent, white, and shiny. As it matures, it turns yellowish to green with or without black markings on the head, thorax, and abdomen. A mature nymph is 3.1 mm long. The shape of the nymph is similar to that of the adult except that the nymph is smaller and is wingless.
As the insect matures, blackish markings on the abdomen become more prominent as well as the blackish band on the last abdominal segment. Eggs are white and elongate or cigar-shaped. Individual eggs are arranged neatly and lie parallel to each other in each egg batch. A single egg measures 0.9 - 0.8 mm. Upon maturation, the egg turns brownish and develops red eyes. |
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The major host of the green leafhopper is the rice plant. It also feeds on a number of grasses. |
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Both nymphs and adults of the green leafhopper feed on rice by sucking the plant sap and plugging the vascular bundles with stylet sheaths. |
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The green leafhoppers are most numerous during the tillering and panicle initiation stages of the crop. Seedling and booting stages are also susceptible. They migrate to the field soon after seedlings have emerged.
They can cause indirect damage to the crop because of the virus diseases that they transmit. |
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Green leafhoppers are important pests. They are vectors of viruses such as tungro, yellow dwarf, yellow-orange leaf, transitory yellowing, and dwarf. |
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There are biological control agents, which are available for the insect. For example, small wasps parasitize the eggs. Mirid bugs also feed on them. Strepsipterans, small wasps, pipunculid flies, and nematodes parasitize both the nymphs and adults. They are also attacked by aquatic veliid bugs, nabid bugs, empid flies, damselflies, dragonflies, and spiders. A fungal pathogen infects both the nymphs and adults of the green leafhopper.
In India, there are some commercially available rice plants that show resistance to the green leafhoppers.
In areas without tungro source, insecticides are not needed. Spraying of insecticide should be avoided because it is often unable to prevent or reduce tungro infections. |
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JLA Catindig and KL Heong |
Rice Doctor © 2003, International Rice Research Institute
