Exogenous Application of dsRNA—Inducing Silencing of the <i>Fusarium oxysporum Tup1</i> Gene and Reducing Its Virulence

oleh: Sen Fan, Yanguang Zhou, Na Zhu, Qingling Meng, Yujin Zhao, Jingyan Xu, Yunjia Tang, Shijie Dai, Xiaofeng Yuan

Format: Article
Diterbitkan: MDPI AG 2024-09-01

Deskripsi

<i>Fusarium oxysporum</i> is a widespread soil-borne fungal pathogen that can infect various plants, causing wilt and root rot diseases. The root rot disease of <i>Atractylodes macrocephala</i> caused by <i>F. oxysporum</i> is among the most serious diseases associated with continuous cropping, significantly hindering its sustainable development. In this study, we aimed to investigate the effect of exogenous application of double-stranded RNA (dsRNA) on silencing the <i>F. oxysporum Tup1</i> gene to reduce its virulence and to evaluate its potential application in controlling root rot disease in <i>A. macrocephala</i>. The <i>Tup1</i> gene was amplified from the <i>F. oxysporum</i> genome, and different lengths of <i>Tup1</i>-dsRNA were designed and synthesized. The uptake of dsRNA by the fungus was verified using <i>Tup1</i>-dsRNA labeled with fluorescein, and in vitro dsRNA treatment experiments were conducted to assess its impact on the growth and virulence of <i>F. oxysporum</i>. Additionally, <i>Tup1</i>-dsRNA was applied to the roots of <i>A. macrocephala</i> to evaluate its effectiveness in controlling root rot disease. The experimental results showed that <i>F. oxysporum</i> could effectively uptake exogenously applied <i>Tup1</i>-dsRNA, significantly reducing <i>Tup1</i> gene expression. All lengths of <i>Tup1</i>-dsRNA inhibited fungal growth and caused morphological changes in the fungal hyphae. Further plant experiments and Reverse Transcription Quantitative Polymerase Chain Reaction (RT-qPCR) analysis indicated that <i>Tup1</i>-dsRNA treatment significantly reduced the incidence of root rot disease in <i>A. macrocephala</i>, which was supported by the reduction in peroxidase (POD) and catalase (CAT) enzyme activities, malondialdehyde (MDA) content, and proline (Pro) levels in treated root tissues. This study demonstrated that exogenous dsRNA could reduce the virulence of <i>F. oxysporum</i> by silencing the <i>Tup1</i> gene and effectively mitigate the root rot disease it causes in <i>A. macrocephala</i>. The successful application of <i>Tup1</i>-dsRNA provided strong evidence for the potential of RNA interference (RNAi) technology in plant disease control. Future research could further optimize the design and application of dsRNA to enhance its practical value in agriculture.