Controle biológico de Meloidogyne incognita associado à promoção de crescimento em alface por microrganismos antagonistas

Abstract

Lettuce (Lactuca sativa L.) is one of the most widely consumed leafy vegetables in Brazil, standing out for its fresh consumption, nutritional importance, and economic relevance for small family farmers. With a significant cultivated area in the country, its production has been increasing, driven by sustainable agricultural practices aimed at ensuring higher quality and food safety. However, lettuce cultivation faces serious phytosanitary challenges, mainly due to the incidence of root-knot nematodes (Meloidogyne spp.), which cause root deformations, compromise plant development, and reduce productivity, often rendering production areas unfeasible. Traditionally, the management of these phytoparasites relies on chemical control, which is not always efficient and often generates environmental impacts and undesirable residues. In this context, the use of beneficial microorganisms emerges as a promising alternative, combining pathogen suppression with the stimulation of plant growth, thus promoting more sustainable agricultural systems. Based on this scenario, two complementary studies were developed. The first aimed to evaluate the effectiveness of different microorganisms applied individually in the control of Meloidogyne incognita and their effects on lettuce development. Isolates of fungi and bacteria were tested under greenhouse conditions, assessing both phytosanitary parameters and plant growth characteristics. The second study investigated the potential of microbial consortia, comparing the combined application of different microorganisms with individual treatments. This approach sought to verify possible synergistic effects capable of enhancing both nematode control and plant development. The results obtained in both studies showed that the tested microorganisms demonstrated potential in the biological management of M. incognita, reducing gall formation and contributing to healthy plant growth. Furthermore, the use of microbial consortia enhanced the beneficial effects, demonstrating the feasibility of integrating different control agents into sustainable management strategies. Therefore, this dissertation confirms the relevance of using microorganisms, either individually or in combination, as an effective and environmentally responsible alternative for nematode management in lettuce cultivation, contributing to the reduction of agrochemical use and strengthening sustainable agricultural practices in Brazil.