<i>Trichoderma viride</i> Isolate Tvd44 Enhances Potato Growth and Stimulates the Defense System against Potato Virus Y

Abstract

Biological treatments may be employed to combat viral plant infections. In this study, Trichoderma viride was applied as a biocontrol agent to enhance the systemic resistance of potato plants against potato virus Y (PVY). T. viride isolate Tvd44 (OQ991378) was isolated and molecularly characterized before being used as an agent against PVY. The foliar application of Tvd44 on PVY-inoculated potatoes significantly promoted plant growth, height, roots, and number of leaves. Results also showed that the levels of peroxidase (POX), polyphenol oxidase (PPO), total proteins, and chlorophyll increased in potato leaves 21 days post-inoculation compared to untreated plants. Results of qPCR assays conducted on Tvd44-treated plants exhibited a reduction in PVY-CP accumulation levels up to 18.76-fold compared to untreated plants (101.82-fold). qPCR results also showed that defense-related genes (PR-1, POD, PAL, CHS, and HQT) were highly expressed in all Tvd44-treated plants. Three compounds: thiocarbamic acid, N,N-dimethyl, S-1,3-diphenyl-2-butenyl ester; 1,1-dicyano-2-methyl-4-(p-cyanophenyl) propane; and trans-[(2,3-diphenylcyclopropyl)methyl] phenyl sulfide were the most abundant compounds detected in the ethyl acetate extract of Tvd44-culture filtrate using GC–MS analysis. Our finding supports the efficacy of T. viride isolate Tvd44 as a potential agent that can successfully control PVY infections in potatoes and increase the productivity of the crop.

Keywords

• <i>Trichoderma viride</i>
• PVY
• potato
• biological control
• defense-related genes
• gene expression