Brown Planthopper (Nilaparvata lugens)

A Silent Threat to Asia’s Rice Fields

If you’re a rice farmer or involved in rice cultivation, you’re likely familiar with the Brown Planthopper—a tiny insect with a massive impact. This destructive pest has caused significant crop losses across Asia, including Thailand. In this article, we’ll explore its biology, life cycle, feeding behavior, and effective control methods that are both practical and sustainable.

Basic Information

• Common Name: Brown Planthopper
• Scientific Name: Nilaparvata lugens (Stål)
• Family: Delphacidae
• Order: Hemiptera

Morphology & Biology

Antennae: Setaceous (hair-like)

Wings:

• Forewings (hemelytra): Hardened at the base, thin and transparent at the tips

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  Hindwings: Membranous and delicate

   

Mouthparts:Piercing-sucking type, used to feed on plant sap

Legs: 

Fore and mid legs: Walking
Hind legs: Modified for jumping
Size: About 3 mm; body is brownish-grey
Adults: Exist in both long-winged and short-winged forms
Behavior:Nocturnal and highly attracted to artificial lights

Life Cycle

The Brown Planthopper undergoes incomplete metamorphosis, which includes:

Egg Stage

• Females can lay up to 200 eggs
• Eggs hatch in about 7 days

Nymph Stage

• Nymphs molt 5 times before becoming adults
• This stage lasts around 10–20 days

Adult Stage

• Adults live for 10–15 days on average
• Capable of mating and egg-laying

Feeding Behavior & Crop Damage

Host Plants: Mainly grasses, especially rice (Oryza sativa)

Damage:

• Nymphs and adults pierce the base of rice plants to feed on sap

• Causes the plant to dry out and die, a condition known as “hopperburn”

Virus Vector:Transmits rice ragged stunt virus and other plant viruses that severely reduce yield

Geographic Distribution

The Brown Planthopper is prevalent throughout tropical and subtropical Asia, including:

• Thailand
• Myanmar
• Cambodia
• China
• India
• Indonesia
• Japan
• And parts of Australia

Integrated Pest Management (IPM) Strategies

Biological Control Agents

Cyrtorhinus lividipennis (Egg Predator Bug): Preys on BPH eggs, consuming 7–10 eggs per day

Lady Beetles (Orange, Anchor-marked, Zigzag patterns): Both larvae and adults feed on BPH eggs and nymphs

Spiders: 

Natural predators that help suppress planthopper populations

Entomopathogenic Fungi

Fungal pathogens that infect and kill Brown Planthoppers include:

• Beauveria bassiana (white fungus)
• Metarhizium spp. (green fungus)
• Hirsutella citriformis

These fungi invade the insect’s body and lead to death, especially in humid environments.

Light Traps

Take advantage of the insect’s attraction to light.
Use light traps to monitor and reduce population levels, particularly at night.

Chemical Control (With Caution)

Use insecticides only when necessary and rotate between chemical groups to avoid resistance:

Contact & Systemic Insecticides:

Organophosphates & Carbamates: 

Long-used chemicals like acephate and carbaryl

Neonicotinoids: 

Highly effective against sucking insects
Examples include:

• Dinotefuran (Starkle)
• Acetamiprid (Molan)
• Thiamethoxam (Actara)
• Clothianidin (Dantosu)
• Imidacloprid (Confidor, Provado)
• Thiacloprid (Calypso)

Important: Rotate chemical classes and apply only when absolutely needed to prevent resistance buildup.

Final Thoughts

Though small and short-lived, the Brown Planthopper reproduces rapidly and can devastate rice yields if left unchecked. Understanding its life cycle and behavior is essential for sustainable management. Combining biological control with selective chemical use offers the most balanced, eco-friendly solution for protecting one of Asia’s most vital crops.