Dynamics of Aleurocanthus woglumi Ashby (Hemiptera: Aleyrodidae) in Tahiti acid lime (Citrus latifolia) orchards under different fertilizer applications

Abstract

Citrus black fly Aleurocanthus woglumi Asbhy is an important citrus pest because it causes significant losses in production. The objective of this study was to evaluate the incidence and distribution of A. woglumi egg laying, eggs and nymphs on Citrus latifolia (Tahiti acid lime) plants grown under different fertilizer applications. The experiment was carried out in a citrus orchard in the municipality of Paço do Lumiar, MA, Brazil. A randomized block design in a 3×5×3 factorial arrangement (three evaluation times, five treatments, and three plant strata) was used with 4 replications. The experimental unit consisted of three plants and treatments with different fertilizations were applied to the soil: T1: control (no fertilizer application); T2: organic fertilizer (bovine manure); T3: organic fertilizer + potassium silicate (K2O3Si); T4: NPK; T5: NPK + K2O3Si. The number of egg laying, eggs and nymphs of A. woglumi was evaluated in the basal, mid and apical strata of C. latifolia plants at 30, 60 and 90 days after fertilizer application. Reductions in the number of eggs and nymphs were observed in treatments with organic fertilization + K2O3Si and NPK + K2O3Si. Citrus latifolia plants treated with K2O3Si were less susceptible to A. woglumi and plants fertilized with NPK present higher susceptibility (p<0.05). There was a higher incidence of egg laying, eggs and 1st instar nymphs in the apical stratum and 2nd, 3rd and 4th instar nymphs in the basal and mid strata in C. latifolia (p<0.05). The addition of K2O3Si to organic and mineral fertilization is recommended as a viable alternative to reduce the population level of A. woglumi in citrus plants