How to control Helicoverpa armigera on soybean in Brazil? What we have learned since its detection

Abstract

See, stats, and : https : / / www. researchgate . net / publication / 305721652 How in ? What detection Article DOI : 10 . 5897 / AJAR2016 . 10903 CITATIONS 2 READS 40 7 , including : Clérison Universidade 9 SEE Adriano Universidade 22 SEE Ivair Iowa 8 SEE Jerson Universidade 41 SEE All . The . The present study was motivated by a lack of information on how to control Helicoverpa armigera in soybean fields in Brazil . Nine chemical and four biological treatments were tested . Control efficiency was evaluated at 3 , 7 , 10 , and 14 days after spraying . Moreover , the cost benefit ratio by the yield and cost of insecticide application and the economic injury level (EIL) were used to calculate the chemical and biological treatments . Chemical insecticides chlorantraniliprole , flubendiamide , chlorfenapyr , spinosad and acephate with 90 . 9 , 90 . 9 , 90 . 9 , 72 . 7 and 90 . 9% of control efficiency , respectively , were efficient to control H . armigera along the evaluations . Bt Control ® was efficient controlling small and large larvae , with 100 and 66 . 7% of control efficiency , respectively . Gemstar ® and HzNPV CCAB ® were efficient against small larvae . The treatments acephate (1 : 10) , chlorantraniliprole (1 : 6 . 6) , flubendiamide (1 : 5 . 3) , Bt Control ® (1 : 6 . 6) , Gemstar ® (1 : 5) and HzNPV CCAB ® (1 : 5 . 7) had higher cost benefit ratio (ratios are indicated in parentheses after the treatments names) . The EIL is flexible and vary according to the control efficiency , cost of treatment application and market value of soybean . The lowest value of EIL was Dipel ® (0 . 2) and the highest value was chlorfenapyr (2 . 3) . These findings support a decision of when , which treatment , and dose to spray to control H . armigera on soybean with a high cost benefit ratio .