Biological studies of the predator Chrysoperla Externa (Neuroptera: Chrysopidae) feeding on the sugarcane borer Diatraea Saccharalis (Lepidoptera: Crambidae): potential for biological control

• Grant number: 24/19126-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2025
• End date: February 28, 2026
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Alessandra Marieli Vacari
• Grantee: Kamila Gabrielly Ribeiro Alves
• Host Institution: Pró-Reitoria Adjunta de Pesquisa e Pós-Graduação. Universidade de Franca (UNIFRAN). Franca , SP, Brazil

Abstract

Lacewings from the genus Chrysoperla (Neuroptera: Chrysopidae) are recognized as essential and widely utilized natural enemies in the biological control of agricultural pests. In Brazil, Chrysoperla externa has been incorporated into augmentative biological control programs since late 2021. Currently, approximately 840,000 hectares are treated annually using this predator, with coffee (Coffea spp.) being the primary crop benefiting from its use, particularly for controlling the coffee leaf miner, Leucoptera coffeella (Lepidoptera: Lyonetiidae). Coffee leaf miner infestations are most severe during the dry, hot season, from August to October. During other months, predator commercialization extends to other crops, including sugarcane (Saccharum spp.), where the sugarcane borer Diatraea saccharalis (Lepidoptera: Crambidae) is prevalent, primarily from October to March. Our hypothesis is that C. externa not only survives but can also proliferate by feeding on the eggs and neonate larvae of D. saccharalis, suggesting that the predator may effectively control the pest before it bores into the sugarcane stalk. This study aims to explore the life history and population parameters of C. externa when preying on D. saccharalis under laboratory conditions, contributing to the development of future biological control programs using lacewings. Although the parasitoids Cotesia flavipes (Hymenoptera: Braconidae) and Trichogramma galloi (Hymenoptera: Trichogrammatidae) are widely used for controlling the sugarcane borer over approximately 3.5 million hectares, Brazil has an estimated 8.6 million hectares of sugarcane cultivation. Therefore, the findings of this research may support the expansion of biological control strategies in additional sugarcane areas across Brazil.