How can spider mites be eliminated in a greenhouse on eggplants? - briefly
Implement regular scouting, raise greenhouse humidity, and treat foliage with horticultural or neem oil to suffocate the pests; introduce predatory mites (e.g., Phytoseiulus persimilis) and, if infestations remain high, apply a label‑approved selective miticide.
How can spider mites be eliminated in a greenhouse on eggplants? - in detail
Spider mites rapidly colonize the foliage of greenhouse‑grown eggplants, feeding on cell contents and causing stippling, bronzing, and leaf drop. Prompt detection and decisive action prevent yield loss.
Sanitation and environmental management reduce infestations. Remove plant debris and weeds that can harbor mites. Keep the greenhouse clean, and dispose of heavily infested leaves. Maintain temperatures above 24 °C and relative humidity above 60 %, conditions that discourage mite reproduction. Rotate crops and avoid planting eggplants in the same aisle for consecutive cycles.
Physical removal limits population buildup. Apply a strong jet of water to foliage twice weekly; the spray dislodges mites and their eggs. Inspect leaves regularly and wipe the undersides with a soft cloth or sponge. Place yellow sticky traps near plant bases to capture mobile stages and monitor density.
Biological agents provide sustainable suppression. Introduce predatory mites such as Phytoseiulus persimilis or Neoseiulus californicus at a rate of 10–15 predators per square meter. Release them when mite counts exceed 5 mites per leaf segment. Augment with entomopathogenic fungi like Beauveria bassiana; apply a spore suspension at 1 × 10⁸ cfu ml⁻¹ to the leaf surface, repeating every 7–10 days.
Selective acaricides serve as a last resort. Use products containing abamectin, spirodiclofen, or bifenazate, adhering to label‑specified concentrations (typically 0.05–0.2 ml l⁻¹). Rotate chemistries with a minimum 7‑day interval to delay resistance. Conduct a pre‑treatment scouting to confirm that chemical action is necessary.
Integrating all tactics yields the most reliable control. Begin with sanitation and environmental adjustments, follow with mechanical removal, introduce predators, and apply chemicals only when monitoring indicates an economic threshold breach. Record mite counts, treatment dates, and environmental parameters to refine future management cycles.