Biological Control of Invasive Mealybug Species

Invasive mealybugs such as the cotton mealybug (Phenacoccus solenopsis), the papaya mealybug (Paracoccus marginatus) and the pink hibiscus mealybug (Maconellicoccus hirsutus) pose serious threats to crops worldwide. Reliance on chemical insecticides is increasingly constrained by resistance development, non-target effects and regulatory restrictions. Biological control offers a sustainable alternative by exploiting natural enemies—predatory insects, parasitic wasps and microbial pathogens—to suppress mealybug populations. Predators such as reduviid bugs, ladybird beetles and lacewings can reduce nymphal densities in the field, while encyrtid and aphelinid parasitoids attack concealed stages, driving down infestation rates. Entomopathogenic fungi and nematodes have also shown promise in breaking pest lifecycles under greenhouse and field conditions. Integrating multiple agents within an integrated pest management framework enhances long-term stability, safeguards beneficial fauna and minimises chemical inputs. Advances in life-history modelling, host–parasitoid interactions and climatic risk mapping now guide targeted releases, augmentative strategies and habitat manipulation, with practical applications in cotton, tomato, cassava and ornamentals across tropical and temperate zones.

Research from Nature Portfolio

A study of the assassin bug Rhynocoris longifrons evaluated its potential as a generalist predator of cotton pests, including the cotton mealybug. Under controlled and field conditions, all life stages of the reduviid demonstrated effective prey suppression, with augmentative releases reducing mealybug populations by around 20–30 percent. Predator releases led to higher crop yields and favourable cost–benefit ratios without disrupting existing natural-enemy assemblages, supporting the inclusion of R. longifrons in integrated programmes against mealybugs and other sap-feeding pests.

Biological Control of Invasive Mealybug Species publication trend

The graph below shows the total number of articles in biological control of invasive mealybug species across all publications each year (not limited to Nature Index journals).

Technical terms

Augmentative release: Supplementary introduction of mass-reared natural enemies to boost control.

Age-stage two-sex life table: Demographic tool accounting for variable development rates across sexes and stages.

Entomopathogen: Microorganism (fungus, bacterium or nematode) that infects and kills insect pests.

Hyperparasitoid: Parasitoid that develops on or within another parasitoid, potentially undermining control.

Integrated pest management (IPM): Coordinated use of biological, cultural and chemical tactics to maintain pest populations below economic thresholds.

Niche model: Predictive framework linking species’ climatic requirements to geographic distribution potentials.

References

1. Using Age-Stage Two-Sex Life Tables to Assess the Suitability of Three Solanaceous Host Plants for the Invasive Cotton Mealybug Phenacoccus solenopsis Tinsley. Plants (2024).
2. Bioefficacy of Rhynocoris longifrons (Stål) (Heteroptera: Reduviidae) against multiple cotton pests under screen house and field conditions. Scientific Reports (2020).
3. The potential global distribution of the papaya mealybug, Paracoccus marginatus, a polyphagous pest. Pest Management Science (2020).
4. Investigating the Parasitoid Community Associated with the Invasive Mealybug Phenacoccus solenopsis in Southern China. Insects (2021).