Vol. 4, Issue 2 (2019)
Impact of rates and frequency of Formulated neem seed oil (F-NSO) on Riptortus dentipes Fab. Hemiptera: Coreidae damage of improved pigeonpea in Owerri, rainforest Zone, of Southeastern, Nigeria
Author(s): Dialoke SA, SO Emosairue, SO Akparobi, CO Cookey, ER Keyagha, VE Ogwudire
Abstract: Research on Riptortus dentipes Fab., Hemiptera: Coreidae) was carried out at the Teaching and Research Farm, School of Agriculture and Agricultural Technology, Federal University of Technology, Owerri Imo, State, during 2009, and 2010 planting seasons. Their damage on pod/seed was studied under control with formulated neem seed oil (F-NSO) and synthetic pyrethroid (SPY) (cypermethrin) at different rates and spraying frequencies. The experiment was laid out in 3 x 5 factorial comprising three rates of F-NSO: 4.2 L ha-1, 8.3 L ha-1, 12.5 L ha-1 with untreated control (0L ha-1), and SPY (1.5L ha-1) as checks and three intervals of application namely : once a week, once in two weeks, and once in three weeks. Results showed that application of F-NSO at the highest dose of 12.5L ha-1 and at four regime spraying intervals of once a week significantly (p<0.05) resulted to reduced pod/seed damage and better pod/seed quality observed irrespective of the planting seasons. July planting season witnessed low pod/seed damage with enhanced seed quality (percentage wholesome seeds) when compared with May planting season. Therefore, in the humid environment of Owerri South-eastern, Nigeria, application of 12.5 L ha-1 of F-NSO once a week and at four spraying intervals especially during July planting season should be incorporated into pigeonpea Integrated Pest Management (IPM) Programmes.