Biocontrol potential of <i>Talaromyces purpureogenus</i> against the wheat powdery mildew fungus <i>Blumeria graminis</i> f. sp. <i>tritici</i>

Talaromyces purpureogenus is known as a mycoparasite that is capable of suppressing plant pathogenic fungi. However, to date, there is little information about the impact of T. purpureogenus on powdery mildews. Based on morphological and molecular biological analyses, T. purpureogenus was identified and confirmed as a mycoparasite on the wheat powdery mildew fungus (Blumeria graminis f. sp. tritici, Bgt, recently clarified as B. graminis s. str.). T. purpureogenus effectively inhibited the colony formation and conidial distribution of Bgt. By inoculation with T. purpureogenus on Bgt, the abundance of Bgt notably decreased by 2.15-, 1.89-, 3.86-, and 25.90-fold at 2, 4, 6, and 8 days post inoculation (dpi), respectively, while the abundance of T. purpureogenus significantly increased by 4.16-, 12.11-, 11.07-, and 6.02-fold at the corresponding time points. In vitro, T. purpureogenus exudates significantly impaired the formation of Bgt appressoria. Therefore, T. purpureogenus acts as a potential biocontrol agent by suppressing the formation, distribution, and development of Bgt conidia, making it a viable alternative for controlling wheat powdery mildew. These results indicate that T. purpureogenus is an antagonistic parasite of wheat powdery mildew, providing new insights for the management of plant pathogenic fungi.