Enhanced Control of Leucoptera coffeella on Coffee Leaves Using Cyantraniliprole-Hybrid Polymeric Membranes

Leucoptera coffeella is a significant lepidopteran pest of coffee (Coffea spp.) crops, capable of causing yield losses of up to 80%. While chemical control with synthetic insecticides remains the predominant strategy, challenges such as pest resistance and environmental contamination highlight the urgent need for more sustainable alternatives. Hybrid polymeric membranes, formulated from Laponite RD clay, sodium alginate, and the insecticide cyantraniliprole, were developed in this study to serve as protective coatings for coffee leaves. Their successful synthesis and the effective integration and interaction of cyantraniliprole within the hybrid matrix were corroborated by proper characterization, including powder X-ray diffraction, Fourier-transform infrared spectroscopy with attenuated total reflectance, thermogravimetric analysis coupled with differential scanning calorimetry, and scanning electron microscopy with energy-dispersive spectroscopy. Bioassay experiments in a greenhouse using seedlings of Catuaí vermelho, a coffee variety of the Coffea arabica species, were conducted in a randomized block design with eight treatments and four replicates. Larval mortality and egg deposition were assessed and statistically analyzed using the Scott-Knott test (p < 0.05). The hybrid membranes significantly increased larval mortality and reduced oviposition compared to both control and commercial insecticide treatments. These findings underscore the potential of these membranes as an eco-friendly alternative for integrated pest management in coffee cultivation, offering advantages such as improved adhesion, sustained release, and reduced pesticide usage.