Susceptibility to cold suggests low risk of establishment of a tropical parasitoid attacking the corn pest Sesamia nonagrioides

• Published in: Biological control 2023-11, Vol.186, p.105359, Article 105359
• Main Authors: Fortuna, Taiadjana M., Anne, Mélissa, Le Gonnidec, Manuel, Jeannette, Rémi, Bressac, Christophe, Rebaudo, François, Mougel, Florence, Kaiser, Laure
• Format: Article
• Language: English
• Subjects: Cotesia typhae; Development; Environmental Sciences; Exotic species; Fecundity; Immature survival; Life Sciences; Risk assessment
• ISSN: 1049-9644; 1090-2112
• DOI: 10.1016/j.biocontrol.2023.105359

[Display omitted] •Lower thermal limits are determined for Cotesia typhae, a tropical parasitoid of Sesamia nonagrioides.•All parasitoid life stages exhibited high levels of cold-susceptibility.•Immature stages suffered high mortality below 15 °C, even in diapausing host larvae.•Adult’s locomotor activity was drastically reduced at low temperatures.•C. typhae have a low risk of establishment in France based on 20 years of winter temperatures. Low temperatures limit the distribution and performance of many crop pests and their natural enemies in non-native areas. Here we evaluated the lower thermal thresholds for survival, development and reproduction of the tropical species Cotesia typhae Fernandez-Triana (Hymenoptera: Braconidae), a gregarious larval parasitoid of Sesamia nonagrioides Lefèbvre (Lepidoptera: Noctuidae), an important corn pest in southern Europe. C. typhae is highly host specific and a very efficient biocontrol agent of S. nonagrioides in greenhouse, with minimal impact on non-target species. Immature and adult stages of the parasitoid were exposed to five constant temperatures ranging from 5 to 27 °C. High mortality was observed in all immature stages below 15 °C and thresholds for egg, larval, and external pupal development were between 10 and 15 °C. Adult locomotor activity decreased dramatically within this temperature range, and males were more susceptible to cold than females. Given these thermal limitations and based on winter temperatures recorded over the past 20 years, we estimated that C. typhae had a low probability to survive in French winters. This finding supports the safe use of C. typhae as an augmentative biological control agent against S. nonagrioides.