Biological Activity of Four Trichoderma Species Confers Protection against Rhizoctonia solani, the Causal Agent of Cucumber Damping-Off and Root Rot Diseases

The cucumber (Cucumis sativa L.) is often subjected to several fungal diseases. Rhizoctonia solani-induced damping-off and root rot are the most common diseases reported from commercial greenhouses of eastern area Saudi Arabia. objective current study explore antagonistic activity four Trichoderma species against R. solani in vitro vivo. Ten isolates (eight belonging AG-4 two AG-A AG2-1) were studied. AG4 pathogenic plants, while AG2-1 non-pathogenic. Seven spp., named T. hamatum KSATR8, harzianum (KSATR9 KSATR10), asperellum (KSATR11, KSATC, KSAT1E), longibrachiatum KSATS isolated, identities both confirmed based on phylogenetic analysis DNA sequence ITS region. dual culture findings indicated that KSATC KSAT1E exhibited significant inhibitory activities solani, with values 79.33 70.89%, respectively. Scanning electron microscope (SEM) images showed a considerable degradation cell wall collapsing hyphae by all species. Under greenhouse conditions, application at concentrations 2 × 108 conidia/mL revealed reduction incidence percentages did not reveal (p < 0.05) difference those Rizolex-T fungicide. Nevertheless, efficacy fungicide attained 86.67%, being higher than which reached 80%. greatest increasing peroxidase, catalase, chitinase enzymes plants. Conversely, elevation polyphenol oxidase enzyme (0.762 0.97 U/g FW) total phenol content (0.55 0.62 mg/g was recorded plants treated KSATR9 KSATR10, statistical results displayed no variations among regarding chlorophyll as response treatments fungicides. Therefore, we endorse using an alternative fungicides manage cucumbers.