Trichoderma hamatum Strain Th23 Promotes Tomato Growth and Induces Systemic Resistance against Tobacco Mosaic Virus

Abstract

Trichoderma hamatum strain Th23, isolated from tomato roots, was molecularly identified using phylogenetic analysis based on ITS, tef1, and rpb2 gene sequences and evaluated for its efficiency in suppressing tobacco mosaic virus (TMV) infection for the first time. Under greenhouse conditions, the application of Th23 promoted tomato growth with significant increases in shoot and root parameters as well as improved total chlorophyll content. Compared to the nontreated tomato plants, the soil pretreatment of tomato plants 48 h before TMV inoculation produced a significant reduction in the TMV accumulation level by 84.69% and enhanced different growth parameters. In contrast, TMV had a deleterious impact on fresh and dry matter accumulation and inhibited photosynthetic capacity. Furthermore, the protective activity of Th23 was associated with a significant increase in reactive oxygen species scavenging enzymes (PPO, CAT, and SOD) as well as decreased nonenzymatic oxidative stress markers (H2O2 and MDA) compared to the TMV treatment at 15 days post-viral inoculation (dpi). In addition, considerable increases in the transcriptional levels of polyphenolic genes (HQT and CHS) and pathogenesis-related proteins (PR-1 and PR-7) were shown to induce systemic resistance against TMV. Consequently, the ability of T. hamatum strain Th23 to promote plant growth, induce systemic resistance, and boost innate immunity against TMV infestation supported the incorporation of Th23 as a potential biocontrol agent for managing plant viral infections. To the best of our knowledge, this is the first report of the antiviral activity of T. hamatum against plant viral infection.

Protective and Curative Activities of Paenibacillus polymyxa against Zucchini yellow mosaic virus Infestation in Squash Plants

“…groups, respectively, compared to the infected treatment group, which asserts the ability of SZYM-CF to stimulate PPO production in squash plants even after 24 h of a ZYMV infection. In addition to its role in oxygen buffering during the photosynthesis process, PPOʹs defensive role in plant tissue was reported [ 63 , 64 , 65 ]. PPO mediates the scavenging of many reactive oxygen species by phenolic compounds, generating lignin that is deposited as a physical barrier against pathogens [ 44 , 66 ].…”

Enhancing systemic resistance in faba bean (Vicia faba L.) to Bean yellow mosaic virus via soil application and foliar spray of nitrogen-fixing Rhizobium leguminosarum bv. viciae strain 33504-Alex1

“…The BYMV inoculation was done on the 21st day of the growth. Briefly, each plant’s two true upper leaves were carborundum-dusted (600 mesh) and mechanically inoculated with BYMV as described previously ( Abdelkhalek et al, 2022 ). All plants were kept under insect-proof greenhouse conditions of 28/16°C (day/night) and 70% relative humidity and were observed daily for symptom development.…”

Ocimum basilicum-Mediated Synthesis of Silver Nanoparticles Induces Innate Immune Responses against Cucumber Mosaic Virus in Squash

“…Upon Ag-NPs application before viral infection, the SOD level was significantly enhanced up to 0.19 ± 0.09 µM/g f. wt in pre-CMV ( Figure 8 ). Thus the pre-application of Ag-NPs could trigger the induced systemic resistance to viral infections through the secretion of enzymes involved in the immune response [ 81 ]. In the same regard, the POX is an essential antioxidant enzyme with several reported defensive mechanisms within plant cells.…”