Formulation of natural products repellents for the control of cockroaches (Periplaneta americana)

Abstract

The use of synthetic pesticides for insect pest control has been under serious attention due to the deleterious effect imposed on both human and the environment. This present study aimed at evaluating the effect of selected indigenous plants (Azadirachta indica, Nepata cateria and Citrus sinensis) for their repellency against cockroach (Periplaneta americana). 200 adult cockroaches were used for the experiment. Cold maceration was the method of extraction of botanicals using ethanol and afterward, experimental insects were introduced to each of the plant extracts using five different doses. Inclusion dose were; 0%extract+100% biscuit (Control), 25%extract+75% biscuit, 50%extract+50% biscuit, 75%Extract+25% biscuit and 100%extract+0% biscuit. Repellency was observed and recorded at interval of 2, 4-, 8-, 12- and 24-hours duration. Results obtained were subjected to statistical analysis to determine the mean repellency, excess proportion index (PI) and percentage repellency. Neem extract showed the highest repellency (93%), followed by Catnip (86%) and Citrus oil had the least (74%) at the highest dose of 2.0g in 24hours exposure. All experimental plants used showed high repellency and maximum PI values in the highest dose (2g). It was concluded that the three botanicals used in this study could be adopted as a repellent in cockroach control.