Flowering plants as sources of attraction and conservation of ladybugs: tactics for biological control of aphids and thrips in lettuce crops

• Grant number: 25/00532-0
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: July 01, 2025
• End date: May 31, 2027
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Terezinha Monteiro dos Santos Cividanes
• Grantee: Tamara Machado da Silva
• Host Institution: Instituto Biológico (IB). Agência Paulista de Tecnologia dos Agronegócios (APTA). Secretaria de Agricultura e Abastecimento (São Paulo - Estado). São Paulo , SP, Brazil
• Associated research grant: 21/11965-3 - Center for the sustainable management of pests, diseases and weeds, AP.CCD

Abstract

Lettuce is considered one of the most appreciated leafy vegetables worldwide, accounting for 50% of Brazil's total leafy vegetable production. One of the challenges for its successful cultivation is the proper management of pests and diseases. Among the predatory insects that contribute to the biological control of aphids and thrips in lettuce, coccinellids (Coleoptera: Coccinellidae), commonly known as lady beetles, stand out. For these predators, prey is not the sole resource for survival and reproduction; nectar and plant pollen are also important food sources, particularly during periods of prey scarcity in the agroecosystem. Certain species of aromatic and medicinal plants, due to their intense flowering, can be cultivated at agricultural field margins to attract, conserve, and enhance populations of natural enemies. Studies conducted at the Laboratory of Entomology and Biological Control of the Instituto Biológico in Ribeirão Preto, SP demonstrated that, in the absence of prey, adult lady beetles Eriopis connexa (Germar) fed exclusively on diets based on flowers from sweet alyssum (Lobularia maritima [L.]), common basil (Ocimum basilicum L.), radishes (Raphanus sativus L.), and buckwheat (Fagopyrum esculentum Moench) survived for up to 33 days. Aiming to provide insights for developing a conservative biological control program in lettuce cultivation, the present project seeks to evaluate the preference of the lady beetles Coleomegilla maculata (De Geer), Hippodamia convergens Guérin-Meneville, and E. connexa for flowers of common basil, radishes, and sweet alyssum. It also aims to determine the longevity and fecundity of these coccinellids in the presence of these flowering plant species and assess, under field conditions, the efficacy of intercropping lettuce with common basil, radishes, and sweet alyssum in establishing these lady beetles for the biological control of aphids and thrips. (AU)