Cyantraniliprole susceptibility baseline, resistance survey and control failure likelihood in the coffee berry borer Hypothenemus hampei.

Cyantraniliprole was recently registered for controlling the coffee berry borer Hypothenemus hampei, the main coffee pest in the world. In this study, baseline determination and resistance monitoring to cyantraniliprole were carried out in Brazilian populations of H. hampei. Evaluations were carried out for three years with representative field-collected populations from nine coffee-producing states in Brazil, using artificial diet containing the insecticide. The likelihood of control failure due to cyantraniliprole resistance was also determined. Populations from Campo do Meio, Linhares and Jaú were more susceptible (<2-fold resistance) to cyantraniliprole than populations from Patrocínio and Londrina (17-fold). Nonetheless, the frequency of cyantraniliprole resistance insects was low and not significant throughout the regions survey and the likelihood of control failure was negligible. Therefore, cyantraniliprole remains an important management tool against the coffee berry borer without current problems of control failure. However, enough field variation in susceptibility to cyantraniliprole exists justifying attention and careful management of this insecticide to prevent quick development of insecticide resistance in populations of this insect pest species.

Translocation of chlorantraniliprole and cyantraniliprole applied to corn as seed treatment and foliar spraying to control Spodoptera frugiperda (Lepidoptera: Noctuidae).

The translocation of chemical insecticides in corn plants could enhance the control of Spodoptera frugiperda, based on their application form. Chlorantraniliprole and cyantraniliprole were applied via seed treatment and foliar spray in corn (VE and V3) to characterize the systemic action of both molecules in leaves that appeared after application. Bioassays with S. frugiperda and chemical quantification in LC-MS/MS confirmed the absorption and upward translocation of chlorantraniliprole and cyantraniliprole by xylem to new leaves. Both insecticides caused the mortality of larvae up to stage V6 (57.5±9.5% for chlorantraniliprole and 40±8.1% for cyantraniliprole), indicating the translocation of insecticides into leaves of corn plants when applied via seed treatment. However, the translocation of chlorantraniliprole and cyantraniliprole from sprayed leaves to new leaves was not observed, regardless of the stage of application plus the next first, second and third stages. An increased dosage of cyantraniliprole did not influence on its translocation in plant tissues, however, it influenced on the present amount of active ingredient. The application of chlorantraniliprole and cyantraniliprole in seed treatment is an important alternative for integrated pest management. The absorption and redistribution capacity of chlorantraniliprole and cyantraniliprole throughout the plant confer a prolonged residual action with satisfactory control of S. frugiperda.