Damage and Loss Caused by ‘Offa’ (Rhyparochromus littoralis dist.) [Heteroptera: lygaeidae] on Groundnut in Song Local Government Area of Adamawa State, Nigeria

Abstract

Field experiments were carried out in four out of six Districts of Song Local Government Area of Adamawa State in Nigeria. The objectives of this research were to establish the damage potential and loss caused by the ‘offa’ [the groundnut sucking bug (Rhyparochromus littoralis Dist.)] on groundnut during the 2011, 2012 and 2013 cropping seasons. The experiment was set up as a split plot design (SPD) where all treatments were replicated three times. The main treatment was the groundnut cultivar in the main plots while the sub-treatments are the harvesting times. The data collected were analyzed using analysis of variance (ANOVA) on SAS statistical package using the generalized linear model and significant P = 0.05, means were separated using Student Neumann- Keuls (SNK) test. Damage caused includes, kernel shriveling, which increases the free fatty acid content of the oil, distortion or discolouration of the kernel, loss in weight and the production of rancid flavor. The percentage reduction of harvested pod and kernels when groundnut was left for 3 – 28 days fell within 24 – 68%. Results obtained from these investigations indicated that R. littoralis causes significant damage on groundnut exposed to the insect pest for more than 3 days in the field before picking (decorting). It was therefore concluded that R. littoralis is a potential economic pest, emerging as a serious threat to the harvesting of quality, healthy and edible groundnut in the study area.