Helicoverpa armigera (Hubner) and Helicovera zea (Boddie) (Lepidoptera: Noctuidae) in Puerto Rico: phenology of flight, analysis of hybrid presence, and insecticide performance in field crops

Authors: FLORES-RIVERA, XIOMARA - Syngenta Seeds, Inc; PAULA-MORAES, SILVANA - Southwest Florida Research And Education Center; JOHNSON, J.W - Syngenta Crop Protection; JACK, C. - Entomological Services; Perera, Omaththage

Submitted to: Journal of Pest Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/17/2022
Publication Date: 11/3/2022
Citation: Flores-Rivera, X.L., Paula-Moraes, S.V., Johnson, J., Jack, C., Perera, O.P. 2022. Helicoverpa armigera (Hubner) and Helicovera zea (Boddie) (Lepidoptera: Noctuidae) in Puerto Rico: phenology of flight, analysis of hybrid presence, and insecticide performance in field crops. Journal of Pest Science. https://doi.org/10.3389/finsc.2022.1010310.
DOI: https://doi.org/10.3389/finsc.2022.1010310

Interpretive Summary: Occurrence of invasive old world bollworm, Helicoverpa armigera, or H. armigera-H. zea hybrids in Puerto Rico was investigated by screening 550 insects collected in Juana Diaz and Salinas collected from 2018 to 2021. The proportion of H. armigera/H. zea and detection of congeneric hybrids were assessed based on the morphology of male genitalia and ITS1 region of ribosomal DNA. The abundance of moths detected in the trapping indicated an increase of the population from October to March, and Juana Diaz had a high occurrence of Helicoverpa spp. than Salinas. Neither H. armigera nor expected hybrids between H. zea and H. armigera were detected in the present study. The susceptibility of H. zea populations to the insecticides Spinetoram, Emamectin benzoate, Chlorantraniliprole, and Esfenvalerate were assessed. The populations from Juana Díaz and Salinas did not differ in insecticide susceptibility. However, an overall significant effect of insecticide susceptibility was detected. Chlorantraniliprole and Emamectin benzoate had the highest performance, with mortality higher than 90%, followed by Spinetoram with mortality above 70%, and Esfenvalerate, which had the lowest. The results will be presented and discussed considering the implication on an IPM program to manage Helicoverpa spp. in seed production in the South of Puerto Rico, and relevance of the results to continental U.S.

Technical Abstract: The genus Helicoverpa (Hardwick) includes several species of destructive agricultural pests around the world. The polyphagous pest Helicoverpa armigera was reported in several countries in South America in 2013. This species was reported in Puerto Rico since 2014 by USDA APHIS. However, information about the impact of this invasive species on field crops, such as corn and soybean, are still needed. Puerto Rico is an important field crop production region, producing seeds for continental U.S and other countries around the world. The objective of this study was to document the occurrence of H. armigera and H. zea in corn, soybean, and sunflower in the southern municipalities of Salinas and Juana Díaz, Puerto Rico. Year-round pheromone trapping of adult males combined with larval sampling was conducted from 2018-2021. The abundance of moths detected in the trapping indicated an increase of the population from October to March, and Juana Diaz had a high occurrence of Helicoverpa spp. than Salinas. The proportion of H. armigera/H. zea and detection of congeneric hybrids were assessed based on genital morphology and DNA analysis. Neither H. armigera nor expected hybrids between H. zea and H. armigera were detected in the present study. The susceptibility of H. zea populations to the insecticides Spinetoram, Emamectin benzoate, Chlorantraniliprole, and Esfenvalerate were assessed. The populations from Juana Díaz and Salinas did not differ in insecticide susceptibility. However, an overall significant effect of insecticide susceptibility was detected. Chlorantraniliprole and Emamectin benzoate had the highest performance, with mortality higher than 90%, followed by Spinetoram with mortality above 70%, and Esfenvalerate, which had the lowest. The results will be presented and discussed considering the implication on an IPM program to manage Helicoverpa spp. in seed production in the South of Puerto Rico, and relevance of the results to continental U.S.