Objective To provide a theoretical basis and technical support for the field application of Trichoderma ghanense ACCC30153, its growth-promoting and disease-resistance functions were analyzed.

Method The study investigated the effects of irrigating poplar seedlings with a conidial suspension of T. ghanense ACCC30153 on growth indicators, physiological indicators, and photosynthesis. The disease resistance function of T. ghanense ACCC30153 was determined through pathogen confrontation tests and by analyzing the expression patterns of disease resistance genes.

Result (1) Irrigating with different concentrations of T. ghanense ACCC30153 conidial suspension promoted the growth of poplar seedlings. Compared with the control, the average height of poplar seedlings increased by 63.99% after 60 days of irrigation with a conidial suspension of T. ghanense ACCC30153 at a concentration of 1.5 × 10⁷ cfu/mL. Additionally, physiological measurements demonstrated a significant increase in chlorophyll, net photosynthetic rate, transpiration rate, stomatal conductance and intercellular CO₂ concentration in leaves compared to the control group (P < 0.05). (2) Comparison of disease resistance in poplar leaves irrigated with or without T. ghanense ACCC30153 conidial suspension revealed a significant improvement in disease resistance after treatment. Enzymatic activity of defense-related enzymes, including phenylalanine ammonia-lyase (PAL), superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), indicated that T. ghanense ACCC30153 enhanced disease resistance by increasing the activity of these defense enzymes in the leaves (P < 0.05). (3)The confrontation experiment showed that T. ghanense ACCC30153 exhibited significant antagonistic effects on against various pathogenic fungi. Furthermore, real-time fluorescence quantitative RT-qPCR analysis revealed that lysozymes and proteolytic enzymes secreted by T. ghanense ACCC30153 played critical roles in its antagonistic effects against pathogenic fungi.

Conclusion This study demonstrated that T. ghanense ACCC30153 can promote the growth of poplar seedlings by increasing chlorophyll content, enhancing photosynthetic rates, and it significantly increased the activity of defense enzymes. Moreover, the T. ghanense ACCC30153 can secrete lytic enzymes and proteolytic enzymes to participate in its antagonism against pathogenic organisms.