| Congresso Brasileiro de Microbiologia 2023 | Resumo: 1371-1 | ||||
Resumo:Chemical fungicides are one of the most common methods applied to control plants pathogens, with environmental and consumer’s concerns. By consequence, biological control alternatives are one of the main targets in basic and applied research programs. Actinomycetes, Gram-positive soil bacteria, are producers of many antimicrobial compounds. Streptomyces, a key group, makes half of known antibiotics. This study assessed the inhibitory activity of two Streptomyces spp. against some of the most important fungi pathogens of agricultural crops worldwide. The assessment used a dual culture plate assay on solid agar and Scanning Electron Microscopy (SEM) images (Figure 1). Inhibition was determined by growth differences between fungi cultured with/out Streptomyces. Isolate 116 inhibited Cercospora kikuchii by 51.5% and isolate 92 by 65.2%. By SEM images, it were observed hyphae damage and reduced fungal mass. Colletotrichum truncatum was inhibited by 85.2% (isolate 116) and 58.4% (isolate 92). SEM for isolate 92 revealed reduced spore production, while for 116 it was observed abnormal hyphal growth. For Corynespora cassiicola, Sclerotinia sclerotiorum and Rhizoctonia solani, inhibitions were from 55.2% to 83.4% with hyphal damages promoted by both isolates for all plant pathogens. In the specific case of S. sclerotiorum, it was observed by SEM images the cessation of hyphal growth (92 isolate), while the formation of resistance structures in the interaction with 116 isolate. In conclusion, both Streptomyces spp. strains emerge as auspicious candidates for biological control of pathogens that afflict important crops worldwide, as soybean, beans, potato, and tomatoes. The findings underscore the burgeoning realm of microbiological products with wider utility, thereby contributing to the pursuit of ecologically sound and sustainable approaches to crop management.
Palavras-chave: Biological control, dual culture, scanning electron microscopy, antibiotics Agência de fomento:Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) | |||||