Foliar Applications of Bacillus subtilis HA1 Culture Filtrate Enhance Tomato Growth and Induce Systemic Resistance against Tobacco mosaic virus Infection

Horticulturae

Hassan Moawad¹  Hamada El-Gendi²  Lóránt Király³  Abdulaziz A. Al-Askar⁴  Marwa A. Samy⁵  Ahmed Abdelkhalek⁵ 

[1] Agriculture Microbiology Department, National Research Centre, Cairo 12622, Egypt;Bioprocess Development Department, Genetic Engineering and Biotechnology Research Institute, City of Scientific Research and Technological Applications, Alexandria 21934, Egypt;Centre for Agricultural Research, Plant Protection Institute, ELKH, 15 Herman Ottó Str., H-1022 Budapest, Hungary;Department of Botany and Microbiology College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia;Plant Protection and Biomolecular Diagnosis Department, ALCRI, City of Scientific Research and Technological Applications, Alexandria 21934, Egypt;

关键词: Bacillus subtilis;    Tobacco mosaic virus;    oxidative stress;    antioxidative enzymes;    gene expression;    GC–MS;   

DOI  :  10.3390/horticulturae8040301

来源: DOAJ

【 摘 要 】

The application of microbial products as natural biocontrol agents for inducing systemic resistance against plant viral infections represents a promising strategy for sustainable and eco-friendly agricultural applications. Under greenhouse conditions, the efficacy of the culture filtrate of Bacillus subtilis strain HA1 (Acc# OM286889) for protecting tomato plants from Tobacco mosaic virus (TMV) infection was assessed. The results showed that the dual foliar application of this culture filtrate (HA1-CF) 24 h before and 24 h after TMV inoculation was the most effective treatment for enhancing tomato plant development, with substantial improvements in shoot and root parameters. Furthermore, compared to non-treated plants, HA1-CF-treated tomato had a significant increase in total phenolic and flavonoid contents of up to 27% and 50%, respectively. In addition, a considerable increase in the activities of reactive oxygen species scavenging enzymes (PPO, SOD, and POX) and a significant decrease in non-enzymatic oxidative stress markers (H₂O₂ and MDA) were reported. In comparison to untreated control plants, all HA1-CF-treated plants showed a significant reduction in TMV accumulation in systemically infected tomato leaves, up to a 91% reduction at 15 dpi. The qRT-PCR results confirmed that HA1-CF stimulated the transcription of several defense-related tomato genes (PR-1, PAL, CHS, and HQT), pointing to their potential role in induced resistance against TMV. GC–MS analysis showed that phenol, 2,4-bis (1,1-dimethylethyl)-, Pyrrolo [1,2-a] pyrazine-1,4-dione, hexahydro-3-(2-methylpropyl)- and eicosane are the primary ingredient compounds in the HA1-CF ethyl acetate extract, suggesting that these molecules take part in stimulating induced systemic resistance in tomato plants. Our results imply that HA1-CF is a potential resistance inducer to control plant viral infections, a plant growth promoter, and a source of bioactive compounds for sustainable disease management.

【 授权许可】

Unknown