Evaluation of the efficacy of extracts of garlic, occumum and pepper for the control of insect pest attack on citrus seedlings

Abstract

Field experiments were carried-out at the experimental site of the National Horticultural Research Institute (NIHORT) Mbato, Okigwe Sub-station in Imo State between March and September, 2010 and was repeated between March and December, 2011 cropping seasons to evaluate the efficacies of extracts of garlic, occimum and pepper for the control of insect pests of citrus seedlings. The treatments were extracts of garlic, occimum, pepper; cypermethrine insectucide and control. The experiment for each season was laid out in a Randomized Complete Block Design (RCBD) with four replications. The results showed that, (Zonocerus variegatus), (Papilo demodcus), (phylocnistes citrella) and (Macrotermes spp) were predominant on the seedlings. All the treatment significantly (p<0.05) reduced insect infestation on the seedlings than the control. Also, Cypermethrine E.C at 12.5% a.i effectively reduced the population of the observed insects in each of the trials. There were no significant (P<0.05) differences between the occimum, garlic and pepper extracts in their efficacies though insect population in the occimum spray was lowest. In the second trial (2011), Percentage of infested leaves/plant and number of dead seedlings were significantly higher in the control (untreated). The tested spice extracts proved effective in the control of major insect pests of citrus seedlings.