Control of Brevicoryne brassicae (Hemiptera: Aphididae) with extracts of Agave americana var. Marginata Trel. in Brassica oleracea crops

Cumulative aphid survival (number of live aphids) over time when exposed to different concentrations of aqueous extracts of agave, water, and deltamethrin. Letters in the legend indicate significance of difference among treatments. Alternative methods of pest control can and should be encouraged, especially those that consider the reality of smallholder family farmers. Here, we evaluated the potential ofAgave americana (agave) extracts for the control of the aphidBrevicoryne brassicae in cabbage (Brassica oleracea L. var acephala) in the field and laboratory. The field experiments consisted of the evaluation of the proportion of dead aphids on cabbage plants after application of agave extracts. In the field, agave mixed with cow milk caused mortality above 80% and was the most effective extract. Agave mixed with water and agave mixed with ethanol elicited mortality above 60%. In the laboratory, we evaluated the mortality of aphids after the application of different concentrations of aqueous agave extracts; the commercial insecticide deltamethrin was included as positive control. Evaluation took place at 3, 6, 12, 24, 48 and 72  hr after applying the treatment. As expected, deltamethrin was the most effective treatment. However, agave extract at concentrations of 0.750 and 0.500 g/mL caused>70% mortality 3 hr after application. We conclude thatA. americana extracts decreased aphid populations and is a promising alternative to the commercial insecticide against aphids in...
Source: Annals of Applied Biology - Category: Biology Authors: Tags: MINOR REVIEW Source Type: research