Activity of Methanolic and Hydrolyzed Methanolic Extracts of Ricinus communis (Euphorbiaceae) and Kaempferol against Spodoptera frugiperda (Lepidoptera: Noctuidae)

Spodoptera frugiperda is the main pest of maize. One of the alternatives proposed for its control is the implementation of products of botanical origin, such as those derived from Ricinus communis. In this work, the insecticidal and insectistatic activities of methanolic and hydrolyzed methanolic extracts of the aerial parts of R. communis and kaempferol against S. frugiperda are evaluated. The methanolic extract presented a larval mortality rate of 55% and an accumulated mortality rate of 65% starting at 4000 ppm, with LC50 values of 3503 (larvae) and 2851 (accumulated); meanwhile, from a concentration of 1000 ppm, a decrease in pupa weight at 24 h of 20.5 mg was observed when compared to the control. The hydrolyzed methanolic extract presented a larval mortality and accumulated mortality rate of 60% from a concentration of 1000 ppm, and a decrease in pupa weight at 24 h of 35.31 mg was observed, when compared to the control. For the compound kaempferol 3-β-D-glucopyranoside, a larval mortality rate of 65% and an accumulated mortality rate of 80% were observed from 800 ppm, with LC50 values of 525.2 (larvae) and 335.6 ppm (accumulated); meanwhile, at 300 ppm, a decrease in pupa weight of 25.59 mg after 24 h was observed when compared to the control.