Brown Plant Hopper in Paddy: Symptoms, Causes, and Control

Brown Plant Hopper (BPH, scientific name Nilaparvata lugens) is a tiny insect pest that feeds on the sap of the paddy plant at the base. It is widely recognized as one of the most disruptive agricultural pests in Asian paddy-growing regions.
Both adults and nymphs feed at the base of the plant and cause yellowing and drying. This condition is known as hopper burn; its patches can wipe out large areas of a field. Found mainly at the base of the paddy plants above the waterline.
Symptoms
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Insects at lower tillers: clusters of insects and nymphs grouped on the stem bases.
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Yellowing of lower leaves: from the tip towards the middle of the leaf.
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Reduced plant vigour: slower growth
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Sooty mould: sticky honeydew secretions accumulate at the base of the plant, forming a black, sooty fungal coating.
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Hopperburn: the most significant one. Leaves turn brown and dry completely, giving a burnt appearance.
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Circular Patches: irregular, oval, yellow patches appear in the field rather than scattered randomly.
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Lodging: weakened plants collapse or fall over easily.
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Stunting: plants remain shorter with poor panicle development.
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Disease transmission: BPH transmits rice ragged stunt virus and rice grassy stunt virus.
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Rice ragged stunt virus: ragged, notched, dark green leaves, twisted leaf margins.
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Rice grassy stunt virus: extreme plant stunting, extreme tillering, pale green to yellow leaves, bushy appearance.
Causes
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Indiscriminate insecticide use: it kills natural predators like wolf spiders (Pardosa pseudoannulata), mirid bugs (Cyrtorhinus lividipennis), parasitoids, damselflies, etc.
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Excess nitrogen application: a heavy dose of nitrogen produces overly lush, soft, sap-rich plant tissues that favour BPH growth.
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Dense, close spacing: it creates a dense canopy that traps moisture and blocks sunlight. This creates a warm, humid, shaded environment in which BPH thrives.
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Continuous cropping: growing paddy on the same land without crop rotation provides a host bridge for BPH to build up over seasons.
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Long-term standing water: standing water in the field, due to continuous flooding or poor drainage, favours BPH infestation.
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Use of susceptible varieties: Growing the same pest-susceptible rice variety over large areas makes it easier for pests to spread rapidly once an infestation starts.
Control
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Drain the field for 3-4 days during early-stage infestation.
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Use split nitrogen application (basal, tillering, panicle initiation).
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Plant crops at a minimum distance of (20 cm × 15 cm) and leave 30 cm between every row of crops every 2-3 meters.
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Use BPH-resistant rice varieties.
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Practice Balanced fertilization.
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Practice alternate wetting and drying (AWD), where possible.
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Protect natural enemies of BPH (spiders, mirid bugs, parasitoids).
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Use light traps at night and yellow pan traps during the day.
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Use bio-insecticides like Azadirachtin 5% EC (80–150 ml/acre), Metarhizium anisopliae 1% WP (1–2 L/acre).
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Apply MIG 303 on your infected crop. It is a bio-pesticide specially formulated for BPH control. Spray at regular intervals of 10-15 days, as pest damage appears.
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Apply chemical control when hoppers reach the Economic Threshold Level (ETL): at the vegetative stage, 5-10 hoppers per hill, and at the panicle initiation stage, 10-20 hoppers per hill․ Commonly recommended products and doses:
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Pymetrozine 50% WG - 120 g/acre
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Dinotefuran 20% SG - 80-100 g/acre
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Triflumezopyrim 10% SC - 94 ml/acre
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Flonicamid 50% WG - 60-80 g/acre
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Thiamethoxam 25% WG - 40 g/acre
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Imidacloprid 17.8% SL - 50-100 ml/acre
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Buprofezin 25% SC - ~400 ml/acre (often used for WBPH/BPH complexes)
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Buprofezin 15% + Acephate 35% WP - 500 g/acre
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Fipronil 5% SC - 400-600 ml/acre
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Acephate 75% SP - 400 g/acre
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Fenobucarb (BPMC) 50% EC - 300-400 ml/acre (2 ml/L)
Note: While spraying, direct the nozzle towards the lower stem or leaf sheath, where BPH concentrates.
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Avoid these :
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Cypermethrin
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Deltamethrin
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Lambda‑cyhalothrin
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Fenvalerate
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Alpha‑cypermethrin
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Methyl parathion
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Fenthion
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Quinalphos
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Malathion
Conclusion
Stop fighting hoppers with hotter sprays. Starve them with drier soil, balanced nitrogen, and a field full of hungry spiders.