Supressão da murcha de Fusarium da bananeira pela aplicação de lodo de tratamento de água em combinação com Trichoderma

Abstract

The increasing generation of organic residues, such as water treatment sludge (WTS), demands sustainable reuse solutions aligned with the principles of the circular economy. This thesis aimed to evaluate the potential use of WTS, focusing on the biological management of Fusarium wilt in banana (Fusarium oxysporum f. sp. cubense – Foc). The approach included a scientometric review to characterize global trends in the use of WTS and identify knowledge gaps in its agricultural application. Experiments were conducted to assess the phytotoxicity potential of WTS on bioindicator plants (lettuce, maize, and beans), as well as its influence on metal accumulation. The inhibitory effect of WTS on the germination of Foc macro- and microconidia was evaluated, along with its compatibility with different biocontrol agents under in vitro conditions. Subsequently, different WTS concentrations (1% to 5%) were evaluated, both alone and in combination with Trichoderma asperelloides, aiming to induce soil suppressiveness to Foc and modulate the microbial rhizosphere community. Results showed that WTS at 3% and 5% significantly altered the soil microbial composition, increasing the diversity and abundance of genera such as Bradyrhizobium spp., Candidatus spp., Paenibacillus spp., Clonostachys spp., Chaetomium spp., and Chloridium spp. Improvements were also observed in soil physicochemical attributes (pH, and electrical conductivity), microbial respiration, enzymatic activity, and plant vegetative growth (height, pseudostem diameter, and SPAD index). However, the combination of sludge with T. asperelloides reduced microbial diversity in several taxa, although it promoted functional genera such as Bacillus spp. and decreased the abundance of Fusarium spp. in the soil. The disease severity, evaluated for the area under disease progress curve, remained high. This research demonstrates that WTS has potential as an organic amendment in the management of plant diseases, provided its use considers soil conditions, phytosanitary history, and impacts on soil microbiota.