Characterization and control of Rhizoctonia solani affecting lucky bamboo (Dracaena sanderiana hort. ex. Mast.) using some bioagents

TCMD: A High-Throughput and Rapid Method for Screening Antimicrobial Ingredients from Renewable Bio-Based Resources

Antibiotic resistance and pathogenic infections underscore the importance and urgency of novel control agent development. Bio-based products represent a rich reservoir of antimicrobial agents. However, traditional strategies for screening new active compounds are time-consuming, costly, and limited by accessible resources. Here, transcriptomic combinatorial molecular docking (TCMD), a novel method enabling fast identification of antimicrobial components in complex mixtures without requiring prior knowledge is proposed. Results show that, in eukaryotic microorganism systems, TCMD demonstrates superior performances in screening antifungal compounds within hydrothermal liquefaction aqueous. The high accuracy is confirmed by molecular dynamics simulation, antifungal experiments, and RT-qPCR (reverse transcription real-time quantitative polymerase chain reaction) analysis. Furthermore, TCMD exhibits cross-system applicability, as evidenced by successful antibacterial substances screening in prokaryotic systems using plant essential oil and traditional Chinese medicine from previous studies. Compared to conventional approaches, TCMD is estimated to be 3-20 times faster and ≈10 times more cost-effective, while maintaining high-throughput capacity for analyzing thousands of compounds simultaneously. These demonstrate that TCMD is a rapid, precise, and flexible method for antimicrobial compound discovery, significantly accelerating the development of new antibacterial agents.

Trichoderma afroharzianum TRI07 metabolites inhibit Alternaria alternata growth and induce tomato defense-related enzymes

Identifying a viable substitute for the limited array of current antifungal agents stands as a crucial objective in modern agriculture. Consequently, extensive worldwide research has been undertaken to unveil eco-friendly and effective agents capable of controlling pathogens resistant to the presently employed fungicides. This study explores the efficacy of Trichoderma isolates in combating tomato leaf spot disease, primarily caused by Alternaria alternata. The identified pathogen, A. alternata Alt3, was isolated and confirmed through the ITS region (OQ888806). Six Trichoderma isolates were assessed for their ability to inhibit Alt3 hyphal growth using dual culture, ethyl acetate extract, and volatile organic compounds (VOCs) techniques. The most promising biocontrol isolate was identified as T. afroharzianum isolate TRI07 based on three markers: ITS region (OQ820171), translation elongation factor alpha 1 gene (OR125580), and RNA polymerase II subunit gene (OR125581). The ethyl acetate extract of TRI07 isolate was subjected to GC-MS analysis, revealing spathulenol, triacetin, and aspartame as the main compounds, with percentages of 28.90, 14.03, and 12.97%, respectively. Analysis of TRI07-VOCs by solid-phase microextraction technique indicated that the most abundant compounds included ethanol, hydroperoxide, 1-methylhexyl, and 1-octen-3-one. When TRI07 interacted with Alt3, 34 compounds were identified, with major components including 1-octen-3-one, ethanol, and hexanedioic acid, bis(2-ethylhexyl) ester. In greenhouse experiment, the treatment of TRI07 48 h before inoculation with A. alternata (A3 treatment) resulted in a reduction in disease severity (16.66%) and incidence (44.44%). Furthermore, A3 treatment led to improved tomato growth performance parameters and increased chlorophyll content. After 21 days post-inoculation, A3 treatment was associated with increased production of antioxidant enzymes (CAT, POD, SOD, and PPO), while infected tomato plants exhibited elevated levels of oxidative stress markers MDA and H2O2. HPLC analysis of tomato leaf extracts from A3 treatment revealed higher levels of phenolic acids such as gallic, chlorogenic, caffeic, syringic, and coumaric acids, as well as flavonoid compounds including catechin, rutin, and vanillin. The novelty lies in bridging the gap between strain-specific attributes and practical application, enhancing the understanding of TRI07's potential for integrated pest management. This study concludes that TRI07 isolate presents potential natural compounds with biological activity, effectively controlling tomato leaf spot disease and promoting tomato plant growth. The findings have practical implications for agriculture, suggesting a sustainable biocontrol strategy that can enhance crop resilience and contribute to integrated pest management practices.