The Status of Insect Pests Prevailing in Stored Wheat Grain under Traditional Storages of Cheha District of Gurage Zone of South Central Ethiopia
Tsehaynew Wubetu *
Department of Biology, College of Natural Sciences, Arba Minch University, Arba Minch, Ethiopia.
Berhanu Hiruy
Department of Biology, College of Natural Sciences, Arba Minch University, Arba Minch, Ethiopia.
*Author to whom correspondence should be addressed.
Abstract
Aim: To assess the status of the insect pests of stored wheat grains in Cheha destrict of Gurage Zone of Southern Ethiopia.
Study Design: Peasant associations were selected purposefully based on intensity of wheat production, such that those peasant association growing wheat predominantly were selected for the survey, while villages, representative farmers and their storage systems were selected randomly using a nested design.
Place and Duration of Study: Survey was conducted between 1, July to 30, December 2019 with the interval of one month in major wheat growing peasant associations of Cheha district of south central Ethiopia.
Methodology: The assessment on abundance was made from of half kilogram of wheat grain sample taken from 135 randomly selected farmer’s storages of three peasant associations using taxonomic keys of books related to stored product insects.
Results: Eight major species of insect pests consisting of four primary pests and four secondary pests belonging to five families with in two insect orders were documented. Of these pests recorded, Sitophilus oryzae, Sitophilus zeamais, Sitotroga cereallella, Tribolium castaneum and Tribolium confusum, respectively were the most prevalent and frequently occurring as they appeared between 12.74 and 33.78 individuals per 100 g of grain and as they occurred in the range between 77.78 and 92.26% per 100 g of sample wheat grain collected from the survey sites, respectively. These were followed by Cryptolestes ferrugineus, Cryptolestes pusillus and Rhyzopertha dominica which occurred between 7.26 and 10.74 individuals per 100 g of grain and in ranges between 51.85 and 66.67% per 100 g of sample wheat grain collected.
Conclusion: The traditional methods and practices used by farmers were inefficient for sufficient wheat grains protection against insect pests in storages; this implies for the urgent need for designing management strategies for more effective and sustainable methods of control.
Keywords: Stored wheat, insect pests, status, species composition, traditional storages.