Incidence, Level of Damage and Identification of Insect Pests of Fruits and Leaves of Ziziphus Tree Species in Ethiopia

Abstract

The Ziziphus tree species offer valuable socio-economic and ecological benefits but experience significant damage from insect pests. In Ethiopia, there is limited knowledge of the insects attacking Ziziphus fruits, and a study aimed to identify these pests, assess their impact and understand how different land use types (LUTs) affect them was conducted. Sampling involved collecting fifty fruits and ten leaves from each of ten randomly chosen Ziziphus trees per LUT within each agroecological zone from August to December in 2022 and 2023. Samples were visually assessed for incidence and infestation levels, and the five morphotypes were identified using molecular techniques through phylogenetic analysis. Fruit pest incidence varied during the season, yet a positive correlation (r = 0.84) was observed among the months and years when assessment took place. Most fruits showed low to medium infestation levels (5%–50%), while severe infestations (>75%) were predominant in the lowland agroecological zone. The insects that had caused the damage were identified as Carpomya incompleta Becker, 1903; Drosophila hydei Sturtevant, 1921; D. simulans Sturtevant, 1919 and Zaprionus indianus Gupta, 1970. Fruits showed higher incidence and infestation levels than leaves, indicating significant yield and income losses. Thus, implementing effective management strategies is vital to minimize these losses and achieve sustainable production in Ethiopia.