Streptomyces yinggelingensis sp. nov. YGL11-2: A novel biocontrol agent with dual activity against banana soil-borne and postharvest fungal diseases

• A novel species named Streptomyces yinggelingensis sp. nov. YGL11-2 was identified. • This novel species possesses broad-spectrum antifungal activities. • Cellular-level study uncovers the strain’s antifungal mechanism. • The strain exhibits biocontrol efficacy against banana fusarium wilt and anthracnose. Banana production is severely threatened by both Fusarium wilt (caused by Fusarium oxysporum f. sp. cubense tropical race 4, Foc TR4) and anthracnose (caused by Colletotrichum musae ), which are devastating soil-borne and postharvest diseases, respectively. Biocontrol using antagonistic microorganisms offers an eco-friendly alternative for managing the concurrent occurrence of soil-borne and postharvest pathogens. In this study, strain YGL11-2 was isolated and characterized as a novel species of Streptomyces through polyphasic taxonomy, for which we propose the name Streptomyces yinggelingensis sp . nov . Genomic analysis of this strain revealed 48 secondary metabolite gene clusters, including compounds such as Ectoine and Anantin C, which exhibit potential antifungal activity. Strain YGL11-2 demonstrated dual antagonistic activity against Foc TR4 and C. musae , with half-maximal effective concentrations (EC 50 ) values of 12.01 mg/L and 25.31 mg/L, respectively. Regarding antifungal mechanisms, strain YGL11-2 extracts disrupted fungal cell membrane structures, caused hyphal and spore wrinkling and breakage, and inhibited spore germination. Pot experiments confirmed that banana seedlings treated with strain YGL11-2 extracts showed a reduced Foc TR4 disease index, achieving a control efficacy of 41.94 %, while significantly promoting root growth (+10.55 cm) and biomass accumulation (+46.40 %). In fruit experiments, bananas treated with strain YGL11-2 exhibited an anthracnose inhibition rate of up to 72.96 %, along with improved quality and delayed ripening. This study is the first to discover a novel Streptomyces species capable of cross-type control of both soil-borne and postharvest diseases, offering a breakthrough solution for controlling both types of banana diseases.