Synergistic effects of varieties, pruning and insecticide applications on white mango scale (Aulacaspis tubercularis Newstead) (Hemiptera: Diaspididae) intensity in Southern Ethiopia

Growth habits of existing mango varieties and poor control practices contributed to the high infestation of A. tubercularis in Ethiopia. The study was aimed to evaluate the integrated effects of variety, pruning practices, and insecticide application in reducing the infestation level and population status of A. tubercularis. Field experiments were carried out in established orchards located in the Arba Mich and Mirab Abaya districts in 2024. Three improved mango varieties, two pruning practices, and three insecticides, including a control, were combined in a factorial arrangement within a randomized complete block design featuring three replicates. Results showed that the Kent variety, along with the pruning practice and Dimethoate 40% EC foliar spray, exhibited an absence of eggs and a sum of life stages per leaf in both locations. Total mortality and a complete reduction in the percentage of eggs per leaf were observed in the pruned Kent variety treated with Dimethoate 40% EC across locations. Control trees of each variety showed the highest mean number of A. tubercularis per leaf and percentage severity when compared with treatments applied to plots. No leaf severity was noted from combinations of the pruned Kent variety and Dimethoate 40% EC spray, which was statistically similar to the same treatment applied to the Apple variety across locations. Thus, growing Kent and Apple mango varieties, along with pruning practices and Dimethoate 40% EC spray, has been identified as the most effective integrated approach for managing A. tubercularis. This strategy is recommended for growers in the study areas and similar agro-ecologies to help sustain mango productivity.