Biological characterization and mating compatibility ofHelicoverpa gelotopoeon(D.) (Lepidoptera: Noctuidae) populations from different regions in Argentina

Abstract

Helicoverpa gelotopoeon, the South American bollworm, is a polyphagous pest of the Heliothinae complex that causes damage to soybean, cotton, and chickpea crops. Some species within this complex have developed resistance to genetically modified crops and insecticides, which has led to increased interest in their genetic diversity and population structure. The objective of this study was to characterize biological and reproductive parameters of two populations of H. gelotopoeon collected in two different provinces of Argentina. Intra- and inter-population crosses revealed that H. gelotopoeon populations from both regions of Argentina did not present evidence of pre-zygotic and post-zygotic incompatibility, suggesting that Tucumán and Córdoba populations of H. gelotopoeon belong to a single wide-ranging species. Our data support the occurrence of substantial gene flow between H. gelotopoeon populations, probably due to the widely documented, long-range migratory capacity of Heliothinae species.

Lack of Reproductive Isolation in Helicoverpa gelotopoeon (Lepidoptera: Noctuidae) Populations from Different Host Plant Species in Argentina

“…This study compared biological and reproductive traits, and mating compatibility between 2 H. gelotopoeon populations collected from different host plants in Tucumán, Argentina. This research complements previous contributions made by Herrero et al (2017), who used H. gelotopoeon populations collected in 2 regions, but in the same crop in Argentina.…”

“…In this context, a study made by Herrero et al (2017) with H. gelotopoeon populations collected from chickpea in 2 regions of Argentina, showed similar biological and reproductive characteristics when reared on artificial diet in the laboratory. In addition, intra-and inter-population crosses revealed that H. gelotopoeon populations from neither region presented evidence of pre-zygotic or post-zygotic incompatibility, suggesting extensive gene flow between Tucumán (northwestern region) and Córdoba (Pampas region) populations of H. gelotopoeon.…”

“…Each population was maintained in the same chamber under identically controlled conditions at 27 ± 2 °C, 70 to 75% relative humidity, and 14:10 h (L:D) photoperiod. Both populations were reared according the methodology described by Murúa et al (2003) and Herrero et al (2017). The food for adults was provided via a cotton plug saturated with a mixture of honey and water (1:1 volume:volume) which was replaced every d. Cages were checked daily for oviposition and adult mortality.…”

“…A crossing experiment was performed to determine reproductive compatibility between soybean (S) and alfalfa (A) populations, according to the methodologies described by Herrero et al (2017). To determine compatibility, a 24-h-old virgin female and virgin male were used.…”

“…According to Herrero et al (2017), the bioecological characteristics of this Heliothinae complex, in addition to the numerous occurrences of insecticide resistance within this subfamily (Forrester 1990;Forrester et al 1993;Armes et al 1996), necessitate establishing alternatives to insecticide control for the 34 species of Helicoverpa. Currently, genetically modified plants expressing genes from the entomopathogenic bacterium Bacillus thuringiensis Berliner (Bacillaceae) (Bt) are available as an alternative strategy to control major lepidopteran pests.…”