In vitro inhibition mechanisms of Trichoderma yunnanense TM10 against Pyricularia oryzae and Rhizoctonia solani causing blast and sheath blight diseases in rice ( Oryza sativa L.)

Blast and sheath blight diseases, caused by Pyricularia oryzae and Rhizoctonia solani, respectively, are major threats to rice production worldwide. Efforts should be made to limit the spread of these phytopathogens, preferably through sustainable methods. In this study, we investigated the antagonistic potential of the local isolate Trichoderma yunnanense TM10 against the pathogenic fungi P. oryzae and R. solani. The results demonstrated that T. yunnanense TM10 inhibited the growth of P. oryzae and R. solani through mechanisms such as competition, mycoparasitism, and antibiosis. Dual culture, filtrate culture, and double plate assays showed that T. yunnanense TM10 could inhibit the growth of both P. oryzae and R. solani. Slide culture and scanning electron microscope (SEM) tests confirmed that T. yunnanense TM10 exhibited mycoparasitic activity, including attachment, coiling, penetration, lysis, and destruction of pathogen hyphae. Additionally, T. yunnanense TM10 was capable of producing cell wall-degrading enzymes (CWDEs) such as chitinase and cellulase, as well as volatile organic compounds (VOCs) such as hydrogen cyanide (HCN). The multifaceted abilities of T. yunnanense TM10 for limiting the growth of P. oryzae and R. solani underscore its potential as an effective biocontrol agent for enhancing productivity and sustainability in rice cultivation.