Insect pests in apple (Malus domestca Borkh) gardens: Review

Apple (Malus domestica), is one of the most important fruit trees cultivated in temperate regions but, newly introduced in Uganda for its income and nutritional importance. However, apples are found to be susceptible to arthropod pests, some known to cause damages on both the plant and fruits. Some of these insect pests are known while others are still unknown and could be effectively managed through integrated pest management methods. For any effective Integrated insect Pest Management, it is necessary to have enough information about the biology and ecology of a given pest, including, spatial distribution and factors that affect pest species’ distribution. Therefore, in this paper, systematic information on insect pests damaging apple fruit trees was reviewed. Different recent literature on insect pests hosted by apples under different agroecological systems of the world was reviewed. The review focused on classifying common insect pests, preferred varieties and their ecological distribution. This was achieved by using the ISI Web of Science bibliographic database and search terms such as apple entomofauna and insect pests were used, with specific keywords of [apple*] AND [insect*] AND [pest]. It was found out that, insect pests in apples belong to several groups of invasive pests which include Coleoptera and Polydrusus (beetles, weevils), Diptera (leaf, seed, fruit flies), Hemiptera (aphids, psyllids, bugs and scales), Hymenoptera (sawflies, wasps ants, bees), Thysanoptera (thrips), Trombidiformes (mites) and Lepidoptera (moths and butterflies) that are of economic value. This work, again reveals dramatic rates of appearance of isect pests in orchards in Africa and elsewhere, which have compromised apple industry’s growth. The review pieced together known information about the insect pests that occurs in apples in different geographical locations. But, information on insect pest in Uganda’s apple orchards remained scanty, which calls for an immediate detailed study on the same.