Effect of cassava varieties on oviposition and development of larger grain borer-Prostephanus truncatus horn (Coleoptera: Bostrichidae)

Abstract

The influence of cassava varieties on the developmental biology of Prostephanus truncatus (Horn) was investigated. This beetle was reared on flour varieties of cassava, namely: Danwari, Nwugo, Aburu-Asua and Ant-Ota. More eggs were lad in Danwari (132.0 +- 6.1 egg) than in other cassava variety. The least number of eggs laid was in Nwugo (118.3+-4.5) in No-choice experiment. In Free-choice test, the highest number of eggs was recorded in Aburu-Asua (64.0 + 17 eggs) and the lowest (41.6 +- 31 eggs) on Anti-Ota. The average total developmental period in, Aburu-Asua, Nwugo, Danwari and Ant-Ota were 32.5 +- 0.4, 30.6 +- 0.2, 28.5 +- 0.1 and 34.7 +- 0.1 days respectively. The low oviposition preference for Nwugo was attributed to the presence of oviposition deterrents in this variety, which might have protected it against the beetle attack.

Keywords: Cassava, Oviposition, Larger grain borer, Coleoptera, Bostrichidae