Adugna Gindaba, Mulugeta Negeri
The maize grains samples were collected from six selected districts of two zones of Western Oromia regional state, Ethiopia in April 2022 and July 2022. The main objective of the study was to assess species composition and relative abundance of maize storage insect pests. The study was conducted in 4 selected districts of Kellem Wollega (Sayo, Hawa Galan, Sadi Chanka, and Dalle Sadi) and in 2 selected districts of West Wollega Zone (Ayira and Lalo Asabi). Samples were collected from farmers’ storage facilities in each selected district. Each samples consisting of 300 g of maize grain seeds were taken and put in plastic jar of 500 ml. Samples were kept for identification of insect pests, and to estimate grain damage and weight loss using count and weight method. The samples were collected two times in the storage periods, namely 3 months and 6 months from the farmer’s storage structures (facilities). Identification was made using combination of insect identification guides by observing under dissecting microscope (20 X). For assessing insect pests’ infestations, the main variables were included relative abundance and constance (frequency of occurrence) of species found in samples. Descriptive statistical analysis (mean and percentage) was performed on percent weight loss, grain damage and germination over the storage periods using IBM SPSS Version 25. Four species of order coleoptera in three families and one species of order Lepidoptera in one family were identified and considered as important pests damaging stored maize in the study areas. From all, Sitophilus zeamais was the most abundant. It is possible to conclude that there was significant grain damage, weight loss and germination loss due to stored maize insect pests in the study area. Enhancing farmers’ knowledge on improvement of existing storage structures and training them on how to handle maize grains is highly recommended.