Inibição do crescimento micelial de Colletotrichum sp. isolado do morangueiro com o uso de extratos obtidos de diferentes resíduos agroindustriais

Abstract

The strawberry is a culture with a large economic importance, mostly in properties based on familiar labor. It’s a culture influenced by several factors during its productive cycle such as biotics and abiotics. Furthermore, it is a culture that normally receives loads of pesticides since it’s affected by several diseases during the production cycle, which one of them is caused by the Colletotrichum sp. fungus. Given this fact, this research objective was evaluate the effects of the manipueira residue, sugar cane bagasse and citrus albedo in the in vitro growing of two Colletotrichum sp. fungus isolated taken from the strawberry culture. These residues were taken from agro industries on the northwestern region in the brazilian state of Rio Grande do Sul. First of all, a pathogenicity test was performed to analyze the morphological differences of the pathogen isolated. The extracts were prepared in 20% (crude extract) and diluted in 0, 5, 10, 15, 20% of concentration, except for the manipueira which dilution was made pure on the mentioned concentrations and 75%. The prepared extracts were filtered in Milipore 0,22 µm filter and mixed in PDA medium. After that, a 5mm diameter disk of the fungus was placed on the culture+extract medium, incubated in 22ºC (295 K) under a photoperiod of 12 hours. The evaluation was done after 7 days. The analysis results showed that the residue of cassava, sugarcane bagasse, sugar cane and citrus albedo effect presented on mycelial growth of Colletotrichum sp. and positively related because as it increases the concentration of the extracts also increases the inhibition of mycelial growth. However, they showed positive correlation, because as much as it increases the extracts, so is the inhibition of the mycelium growing. Therefore, in order to obtain fungicide effects, it must be tested agro industrial residue in largest concentrations and different extract obtaining processes.