On cucumbers spider mite: what should be done in a greenhouse and what control measures should be applied? - briefly
Maintain optimal greenhouse conditions—moderate humidity, adequate ventilation, and regular leaf inspections—to prevent spider mite outbreaks on cucumbers; when infestations appear, employ integrated control using selective miticides (e.g., abamectin or spinosad), release predatory mites such as Phytoseiulus persimilis, and remove heavily infested foliage.
On cucumbers spider mite: what should be done in a greenhouse and what control measures should be applied? - in detail
Cucumber spider mite infestations in greenhouse production require early detection, environmental manipulation, and integrated pest‑management (IPM) tactics. Regular scouting of the undersides of leaves with a 10× magnifier identifies population thresholds; an average of five motile mites per leaf segment signals the need for intervention.
Environmental control reduces mite reproduction. Maintain relative humidity above 60 % and keep temperatures between 18 °C and 24 °C; high humidity interferes with egg viability, while temperatures above 30 °C accelerate mite mortality. Ventilation fans and misting systems should provide uniform leaf wetness without causing waterlogging.
Cultural measures limit colonization sources. Remove volunteer cucumbers and weeds that serve as reservoirs. Rotate crops with non‑host species such as lettuce or basil for at least one cycle. Clean and disinfect benches, trays, and tools between batches; use a 1 % sodium hypochlorite solution for surface sanitation.
Biological agents offer selective suppression. Introduce predatory mites (e.g., Phytoseiulus persimilis, Neoseiulus californicus) at a release rate of 10–20 predators per square metre. Ensure compatible conditions: low pesticide residues, adequate humidity, and continuous prey availability. Augment with entomopathogenic fungi (Beauveria bassiana) applied as a foliar spray at 1 × 10⁹ conidia L⁻¹; repeat applications every 7 days until mite counts decline.
Chemical options serve as a last resort. Select acaricides with short residual activity and low phytotoxicity, such as abamectin (0.5 mg L⁻¹) or spirodiclofen (0.2 mg L⁻¹). Rotate active ingredients to prevent resistance; follow label‑specified pre‑harvest intervals. Avoid broad‑spectrum insecticides that harm beneficial predators.
Monitoring continues after treatment. Record mite counts weekly, noting temperature, humidity, and control actions. Adjust IPM components based on trends: increase biological releases if mite resurgence occurs, or modify environmental parameters to sustain predator efficacy.
Implementing these steps—environmental regulation, sanitation, crop rotation, biological agents, and judicious chemical use—provides a comprehensive framework for managing cucumber spider mite pressure in greenhouse environments.