evaluation of spent engine oil and other natural materials on the emergence of harvester ants (messor galla forel)

Harvester ants (messor galla forel) defied various control strategies. two field experiments were conducted to evaluate the effects of spent engine-oil and other naturebased materials on their emergence in maiduguri, borno state of nigeria. the treatments evaluated are spot application of spent engineoil and some natural materials in experiment 1 and individual and equal mixture of pure neem seed kernel oil and spent engine-oil in experiment 2. spot application of permethrin served as control. experiment 1 results shows no significant difference (p > 0.05) between permethrin and spent engine-oil (which was the most effective treatment). while neem seed oil was significantly (p < 0.01) more effective than the untreated control, the result on the 28th day after application showed no significant difference (p > 0.05) in the population index of ants that emerged from nests treated with aqueous neem seed extract, salt/potash solution and extract of eugenia aromatic fruit from those of the control. experiment 2 result showed no significant difference (p < 0.05) between permethrin, spent engine-oil, neem seed kernel oil and, equal mixture by volume of pure neem seed kernel oil and spent engine-oil in controlling the emergence of the ants. these were however, significantly different (p > 0.05) from the untreated control. while the result shows no significant difference between the treatments, it was observed that equal mixture of spent engine-oil and neem seed kernel oil was most effective, followed by spent engine-oil, permethrin and neem seed kernel oil, in that order.