Effect of Rabbit Urine on the Larval Behavior, Larval Mortality, Egg Hatchability, Adult Emergence and Oviposition Preference of the Fall Armyworm (Spodoptera frugiperda J.E. Smith)

Abstract

The fall armyworm (FAW) (Spodoptera frugiperda J.E. Smith) is a major cereal pest threatening food security in Africa. African smallholder farmers apply various indigenous pest management practices, including rabbit urine; however, there is no scientific evidence for its efficacy. The FAW eggs, first, second and third instar larvae and moths were exposed to rabbit urine-treated maize leaves alongside untreated maize leaves (control). More FAW larvae (46.0–70.0%) remained on the untreated leaves than those (27.0–43.0%) on the rabbit urine-treated leaves. Rabbit urine caused 6.4 and 12.8% damage reduction of the second and third instars, respectively, 24 h post-exposure. Rabbit urine significantly reduced the survival of FAW, had a lethal time (LT50) of 5.0, 7.3 and 8.7 days and a lethal dose (LD50) of 48, 94, and 55% for the first, second and third instars, respectively. Egg hatchability and adult emergence were reduced by 55.0 and 13.3%, respectively. The FAW female moths laid more eggs on the rabbit urine-treated plants (647 ± 153 eggs) than they did on the untreated plants (72 ± 64 eggs). This study confirms farmers’ assertions about using rabbit urine to manage FAW. For successful integration into the FAW IPM package, additional studies on the chemistry of rabbit urine, the behavioral response and the field might be required.