Characterization of a bacterial strain T226 and its efficacy in controlling post-harvest citrus anthracnose

Postharvest anthracnose of citrus, caused by the fungus <i>Colletotrichum gloeosporioides</i>, leads to significant economic losses. There is a growing need for effective biological control agents to manage this disease. In this study, a bacterial strain (T226) with antagonistic potential was isolated from sugarcane rhizosphere soil. It was identified as <i>Lysobacter enzymogenes</i> through a polyphasic approach, encompassing 16S rDNA phylogenetic analysis (with 100% bootstrap support), morphological observation, and physiological and biochemical characterization. Strain T226 demonstrated strong and stable antagonistic activity against <i>C. gloeosporioides</i>. Its efficacy remained consistent over eight continuous subcultures on artificial media, indicating high metabolic stability. <i>In vivo</i> biocontrol assays confirmed its potency. Specifically, artificial stab inoculation tests showed a disease control efficacy of 78.2%, while under conditions of natural infection, T226 achieved control efficacies of 61.3% at 20 and 60 days post-application. To our knowledge, this is the first report identifying <i>Lysobacter enzymogenes</i> as a highly effective biocontrol agent against citrus postharvest anthracnose. The high stability and significant efficacy of strain T226 underscore its considerable potential for practical application in postharvest protection during citrus storage.