Limited occurrence of foliar-, root-, and seed-applied neem seed extract toxin in untreated plant parts

A 1% solution of neem (Azadirachta indica A. Juss.) seed extract used against Liriomyza trifolii (Burgess) failed to increase the toxicity of untreated chrysanthemum foliage (Dendranthema morifolium (Ramat) Tzvel.) positioned above or below sprayed foliage. Untreated bean (Phaseolus limensis MacF.) leaves opposite to leaves painted with 0.4% extract were not as toxic to L. trifolii as painted leaves. Foliage on chrysanthemum cuttings that were root-dipped in 0.4% extract was toxic to leafminers but subsequent new foliage was not. Bean seeds soaked in 4% extract for 6 h germinated to seedlings which were not significantly more toxic to L. trifolii than untreated seedlings.