Effect of Nutritional Content of Processed Cassava Chips on Development of Prostephanus truncatus (Horn)

Abstract

Samples of four differently processed cassava chips of two varieties were analysed for their chemical contents. Thereafter, they were infested with adults of Prostephanus truncatus at temperature of 25-34°C and relative humidity of 61-92% and studied for their susceptibility to pest in storage. The processed chips differed in their overall chemical contents and their responses to P. truncatus attack were significantly different (P<0.05). The beetles performance and overall development was high on fermented cassava chips which had highest pest population density (619.9±74.5) and suffered the greatest weight loss (71.7±8.8) than on parboiled chips with population density of (220.6± 48.6) and loss of (20.9±5.0). Correlation analysis between the biology of the pest and the chemical composition of the chips showed that association between the starch and population density of the pest was positive and significantly high (r = 0.71, P<0.05). Weight loss due to insect feeding also showed significant association with the starch content of the cassava chips (r = 0.82, P<0.05).