کارایی بالقوه کنترل زیستی گونه‌های تریکودرما در برابر سوختگی دیررس سیب‌زمینی

Potato (Solanum tuberosum) is one of the most important staple tuber crops in the world, playing a significant role in ensuring food security. One of the most important diseases affecting potatoes is late blight, which is primarily caused by the death of the plant and tuber infection, posing a major issue for potatoes globally. The causal agent of this disease is a fungus-like oomycete called Phytophthora infestans. In recent years, biological control agents have gained significant importance as sustainable, eco-friendly alternatives for disease management. Biological control of plant diseases offers a safer alternative to chemicals, without harmful effects on human health or the environment, providing sustainable, cost-effective, and eco-friendly management for plant pathogens. This study aimed to assess the impact of biological control using Trichoderma strains on late blight disease in potatoes. In this study, the antagonistic effects of two Trichoderma strains on P. infestans were evaluated under laboratory and greenhouse conditions. In greenhouse studies, two potato varieties (a disease-susceptible variety, Agria, and a disease-resistant variety, Jelly) were selected. The Trichoderma inoculation was performed at the time of planting tubers in the soil, and zoospore inoculation was done on the aerial parts at the 4-leaf stage of the seedlings. The in vitro antagonistic results between Trichoderma virens and P. infestans showed that the diameter growth of the pathogen was reduced by over 82%. Under greenhouse conditions, in the sensitive potato variety, T. virens significantly reduced the infection of P. infestans compared to the resistant variety. Trichoderma also enhanced resistance to late blight in the plants by inducing systemic resistance and increasing total phenolic content, as well as the activity of antioxidant enzymes related to defense (catalase, guaiacol peroxidase, polyphenol oxidase, and phenylalanine ammonia-lyase) and the transcription levels of genes associated with WRKY, PAL, and MAPK transcription factors. Moreover, the use of T. virens following pathogen inoculation increased the total protein level by 1.9 times in the susceptible variety. This study highlighted the role of T. virens as an antagonist to the late blight pathogen, which induces disease resistance. The use of this microorganism in conventional agricultural systems can reduce management costs and environmental pollution.