Aschersonia aleyrodis

Aschersonia aleyrodis is a group of entomopathogenic fungi that function as highly specialized biological insecticides against specific insect pests.

The mode of action begins when fungal spores adhere to the insect's cuticle and germinate, triggered by favorable humidity levels.

Hyphae penetrate the insect's body through the exoskeleton using a combination of mechanical pressure and enzymatic degradation.

Once inside, the fungus consumes the host's internal tissues, leading to the rapid death of the pest and cessation of feeding.

Finally, the fungus emerges through the insect's cuticle to produce new spores, allowing for secondary spread within the pest population.

This group of fungi is primarily utilized to combat various species of whiteflies, most notably the greenhouse whitefly (Trialeurodes vaporariorum).

They are also highly effective in controlling populations of scale insects and soft scales, which are common pests of citrus and indoor plants.

Biological treatment is most successful when targeting early nymphal stages of the insects, which are more susceptible to fungal infection.

Greenhouse crops, ornamental flowers, and citrus groves are the primary agricultural sectors where these bio-agents are applied.

By focusing on these specific pests, the treatment provides a targeted approach that protects beneficial insects from harm.

Effective application requires maintaining high relative humidity, ideally above 70%, to ensure proper germination of fungal spores on plant surfaces.

Temperature management is critical, with the most active growth observed in the range between 20°C and 28°C.

Applications should be performed in the late afternoon or during cloudy weather to minimize exposure to harmful UV radiation.

Thorough coverage of the plant canopy is essential, particularly the undersides of leaves where nymphs typically reside.

Regular monitoring of pest levels should dictate the frequency of applications, usually scheduled at 10 to 14-day intervals.

Compatibility with chemical fungicides is a major limitation, as synthetic antifungal products can severely inhibit fungal growth.

The shelf life of the prepared spray mixture is very short; it must be used immediately after preparation to maintain viability.

Storage conditions must be strictly controlled, keeping the product cool and away from direct sunlight to preserve spore health.

Avoid applying synthetic broad-spectrum insecticides concurrently, as they may negatively interact with the biological agent.

Operators should use standard protective equipment when handling large volumes of biological products to prevent potential respiratory irritation.