Species compositions and relative abundance of insect pests associated with stored dried cassava chips in selected markets in Oyo state, Nigeria
Braimah Jafar A, Popoola Kehinde Olajide K
Field survey was conducted in four purposively selected markets; Bodija, Oja-Agbe, Sango and Sabo in Oyo state based on the availability of dried cassava chips (DCC) between April 2016 and March, 2017. Four stores were selected within a market for monthly sampling for insect pest species. 4kg DCC were sampled from the stock in each stores for occurrence and insect pest’s determination. Relative abundance in percentage of occurred insect pest species were determined. Data collected were analysed using descriptive statistics. A total of 11174 identified coleopteran insect pest species belonging to Five (5) families; Bostrichidae, Curculionidae, Trogossitidae, Tenebrionidae and Laemophidae grouped into seven species were obtained. The species relative abundance in percentage in decreasing order are: Prostephanus truncatus (Horn) 39.61%, Dinoderus species 25.95%, Ryzopertha dominica 24.11%, Sitophilus species 3.62%, Tenebroides species 0.22%;Tribolium species 5.82%, Cryptolestes species 0.67%. The result also indicates species abundance were more prevalent is Oja-Agbe than other markets investigated. Result also showed that highest abundance of insect pest species was observed in rainy season (85.20%) compared to dry season (14.80%). This study has showed that stored dried cassava chips in, markets are not immune to insect pest infestation with infestation occurring all year round.