Resumo

RIVERA-HERNANDEZ, Mitchel et al. Effect of extracts of Citrus sinensis (Rutaceae) and Trichilia havanensis (Meliaceae) in mortality and repellence of Tetranychus urticae (Acari: Tetranychidae). Biotecnia [online]. 2023, vol.25, n.3, pp.154-161.  Epub 27-Maio-2024. ISSN 1665-1456.  https://doi.org/10.18633/biotecnia.v25i2.2107.

This work aimed to evaluate the effect of the plant extract from Citrus sinensis peel and Trichilia havanensis seeds, on mortality and repellency in different biological states of Tetranychus urticae under laboratory conditions. Solutions of the extracts at 500, 1000, and 1500 mg•L-1 were applied to a known number of eggs, larvae, and female adults of T. urticae in foliar discs of bean (Phaseolus vulgaris L.). The data analysis of mortality percentage and the repellence (Kruskal-Wallis test and comparison of medians, α = 0.05) showed that the T. havanensis extract presented the highest percentage of mortality in eggs with 45.0 % at 1500 mg•L-1, and the C. sinensis extract presented the highest mortality in larvae with 40.0 % at 1000 mgL-1 and adults with a 50.0 % at 1500 mg•L-1. The highest percentage of repellency was the C. sinensis extract at 1500 mg•L-1, with 30.0 % in larvae and 60.0 % in adults. The results indicate that the extracts have the potential to develop effective products for managing T. urticae.

Palavras-chave : Egg mortality; larvae repellency; chemical characterization; vegetal extract.