While many plant viruses cause diseases that reduce crop yield, quality, and overall plant health, not all viruses are purely detrimental. Under certain conditions, some can confer beneficial effects, including improving abiotic stress tolerance, enhancing immunity, or even increasing pollination efficiency. RNA viruses, though most often associated with disease, can also establish symbiotic relationships with their hosts that are mutualistic, commensal, or conditionally beneficial depending on environmental factors. This mini-review summarizes how mild viral infections can protect plants against more severe pathogens (cross-protection), induce signaling and epigenetic changes that enhance stress tolerance, and serve as tools for gene delivery and crop improvement. Collectively, these findings underscore the potential of RNA viruses to support plant adaptation and survival, offering innovative possibilities for sustainable agriculture and climate resilience.

Academy of Scientific and Innovative Research Ghaziabad Uttar Pradesh India

Laboratory of Cell Cycles of Algae Centre Algatech Institute of Microbiology of the Czech Academy of Sciences Třeboň Czechia

Plant Virology Lab Council of Scientific and Industrial Research Palampur Himachal Pradesh India

Zobrazit více v PubMed

Al-Hamdani S., Stoelting A., Morsy M. (2015). Influence of symbiotic interaction between fungus, virus, and tomato plant in combating drought stress. Am. J. Plant Sci. 6, 1633–1640. doi:  10.4236/ajps.2015.610163 DOI

Al-Khayri J. M., Rashmi R., Surya Ulhas R., Sudheer W. N., Banadka A., Nagella P., et al. (2023). The role of nanoparticles in response of plants to abiotic stress at physiological, biochemical, and molecular levels. Plants 12, 292. doi:  10.3390/plants12020292, PMID: PubMed DOI PMC

Ando S., Miyashita S., Takahashi H. (2019). Plant defense systems against cucumber mosaic virus: Lessons learned from CMV–Arabidopsis interactions. J. Gen. Plant Pathol. 85, 174–181. doi:  10.1007/s10327-019-00850-4 DOI

Augustine S. M., Tzigos S., Snowdon R. (2023). Heat-killed tobacco mosaic virus mitigates plant abiotic stress symptoms. Microorganisms 11, 87. doi:  10.3390/microorganisms11010087, PMID: PubMed DOI PMC

Bhar A., Chakraborty A., Roy A. (2021). Plant responses to biotic stress: Old memories matter. Plants 11, 84. doi:  10.3390/plants11010084, PMID: PubMed DOI PMC

Bhattacharjee B., Tiwari S., Singh R., Mansoor S. (2022). Geminivirus-derived vectors as tools for functional genomics. Front. Microbiol. 13. doi:  10.3389/fmicb.2022.799345, PMID: PubMed DOI PMC

Broecker F., Moelling K. (2019). Evolution of immune systems from viruses and transposable elements. Front. Microbiol. 10. doi:  10.3389/fmicb.2019.00051, PMID: PubMed DOI PMC

Cisneros A. E., Alarcia A., Llorens-Gámez J. J., Puertes A., Juárez-Molina M., Primc A., et al. (2025). Syn-tasiR-VIGS: Virus-based targeted RNAi in plants by synthetic trans-acting small interfering RNAs derived from minimal precursors. Nucleic Acids Res. 53, gkaf183. doi:  10.1093/nar/gkaf183, PMID: PubMed DOI PMC

Ellendorff U., Fradin E. F., De Jonge R., Thomma B. P. H. J. (2009). RNA silencing is required for Arabidopsis defence against Verticillium wilt disease. J. Exp. Bot. 60, 591–602. doi:  10.1093/jxb/ern306, PMID: PubMed DOI PMC

Fan S., Jia L., Wu J., Zhao Y. (2025). Harnessing the potential of CRISPR/cas in targeted alfalfa improvement for stress resilience. Int. J. Mol. Sci. 26, 3311. doi:  10.3390/ijms26073311, PMID: PubMed DOI PMC

Gentzel I. N., Ohlson E. W., Redinbaugh M. G., Stewart L. R., Domier L. L., Krenz B., et al. (2022). VIGE: Virus-induced genome editing for improving abiotic and biotic stress traits in plants. Stress Biol. 2, 2. doi:  10.1007/s44154-021-00026-x, PMID: PubMed DOI PMC

Groen S. C., Jiang S., Murphy A. M., Cunniffe N. J., Westwood J. H., Davey M. P., et al. (2016). Virus infection of plants alters pollinator preference: A payback for susceptible hosts? PloS Pathog. 12, e1005790. doi:  10.1371/journal.ppat.1005790, PMID: PubMed DOI PMC

Hur S. (2019). Double-stranded RNA sensors and modulators in innate immunity. Annu. Rev. Immunol. 37, 349–375. doi:  10.1146/annurev-immunol-042718-041356, PMID: PubMed DOI PMC

Khankhum S., Sela N., Osorno J. M., Valverde R. A. (2016). RNA-seq analysis of endornavirus-infected vs. endornavirus-free common bean (Phaseolus vulgaris) cultivar Black Turtle Soup. Front. Microbiol. 7. doi:  10.3389/fmicb.2016.01905, PMID: PubMed DOI PMC

Lee R. F., Keremane M. L. (2013). Mild strain cross protection of tristeza: A review of research to protect against decline on sour orange in Florida. Front. Microbiol. 4. doi:  10.3389/fmicb.2013.00259, PMID: PubMed DOI PMC

Leonetti P., Stuttmann J., Pantaleo V. (2021). Regulation of plant antiviral defense genes via host RNA-silencing mechanisms. Virol. J. 18, 231. doi:  10.1186/s12985-021-01664-3, PMID: PubMed DOI PMC

Licciardello G., Scuderi G., Russo M., Raspudi S., Caruso A. G., Catara A., et al. (2023). Minor variants of Orf1a, p33, and p23 genes of VT strain citrus tristeza virus isolates show symptomless reactions on sour orange and prevent superinfection of severe VT isolates. Viruses 15, 2037. doi:  10.3390/v15102037, PMID: PubMed DOI PMC

Lundstrom K. (2023). Self-replicating vehicles based on negative strand RNA viruses. Cancer Gene Ther. 30, 771–784. doi:  10.1038/s41417-022-00520-8 PubMed DOI PMC

Mahmood M. A., Naqvi R. Z., Rahman S. U., Alotaibi S. S., Nazar A., Sarwar M. B., et al. (2023). Plant virus-derived vectors for plant genome engineering. Viruses 15, 531. doi:  10.3390/v15020531, PMID: PubMed DOI PMC

Mandadi K. K., Scholthof K. B. G. (2013). Plant immune responses against viruses: How does a virus cause disease? Plant Cell 25, 1489–1505. doi:  10.1105/tpc.113.111658, PMID: PubMed DOI PMC

McRae A. G., Ahmed I., Saur I. M. L., Ellwood S., Deller S., Wilson C. R., et al. (2023). Spray-induced gene silencing to identify powdery mildew gene targets and processes for powdery mildew control. Mol. Plant Pathol. 24, 1168–1178. doi:  10.1111/mpp.13361, PMID: PubMed DOI PMC

Nerva L., Guida G., Vallino M., Luca E., Chitarra W., Chiapello M., et al. (2022). Spray-induced gene silencing targeting a glutathione S-transferase gene confers protection to Nicotiana benthamiana and Brassica juncea against Sclerotinia sclerotiorum. Plant Cell Environ. 45, 1620–1633. doi:  10.1111/pce.14228, PMID: PubMed DOI

Papareddy R. K., Palomar M., Ramesh S. V., Khraiwesh B., Choi H. S., Manavella P. A., et al. (2020). Chromatin regulates expression of small RNAs to help maintain transposon methylome homeostasis in Arabidopsis. Genome Biol. 21, 251. doi:  10.1186/s13059-020-02173-6, PMID: PubMed DOI PMC

Pechinger K., Chooi K. M., MacDiarmid R. M., Harper S. J., Ziebell H. (2019). A new era for mild strain cross-protection. Viruses 11, 670. doi:  10.3390/v11070670, PMID: PubMed DOI PMC

Prabahar A., Swaminathan S., Loganathan A., Jegadeesan R. (2015). Identification of novel inhibitors for tobacco mosaic virus infection in Solanaceae plants. Adv. Bioinf. 2015, 198214. doi:  10.1155/2015/198214, PMID: PubMed DOI PMC

Pumplin N., Voinnet O. (2013). RNA silencing suppression by plant pathogens: Defence, counter-defence and counter-counter-defence. Nat. Rev. Microbiol. 11, 745–760. doi:  10.1038/nrmicro3120, PMID: PubMed DOI

Rattan U. K., Kumar S., Kumari R., Mishra R., Singh A., Choudhary M., et al. (2022). Homeobox 27, a homeodomain transcription factor, confers tolerance to CMV by associating with cucumber mosaic virus 2b protein. Pathogens 11, 788. doi:  10.3390/pathogens11070788, PMID: PubMed DOI PMC

Resour G., Evol C., Dos C., Martins C., Pereira L., Silva A., et al. (2025). Effect of papaya ringspot virus infection in Brazilian Carica papayaaccessions under controlled conditions. Genet. Resour. Crop Evol. 72, 7223–7233. doi:  10.1007/s10722-025-02383-2 DOI

Roossinck M. J. (2011). The good viruses: Viral mutualistic symbioses. Nat. Rev. Microbiol. 9, 99–108. doi:  10.1038/nrmicro2491, PMID: PubMed DOI

Roossinck M. J. (2015). Plants, viruses and the environment: Ecology and mutualism. Virology 479–480, 271–277. doi:  10.1016/j.virol.2015.03.041, PMID: PubMed DOI

Sanjuán R., Domingo-Calap P. (2016). Mechanisms of viral mutation. Cell. Mol. Life Sci. 73, 4433–4448. doi:  10.1007/s00018-016-2299-6, PMID: PubMed DOI PMC

Schmitt M. J., Breinig F. (2002). The viral killer system in yeast: From molecular biology to application. FEMS Microbiol. Rev. 26, 257–276. doi:  10.1111/j.1574-6976.2002.tb00614.x, PMID: PubMed DOI

Scholthof K. B. G., Adkins S., Czosnek H., Palukaitis P., Jacquot E., Hohn T., et al. (2011). Top 10 plant viruses in molecular plant pathology. Mol. Plant Pathol. 12, 938–954. doi:  10.1111/j.1364-3703.2011.00752.x, PMID: PubMed DOI PMC

Shukla K., Nikita, Singh P., Gupta R., Verma S., Ahmad A., et al. (2025). Phytohormones and emerging plant growth regulators in tailoring plant immunity against viral infections. Physiologia Plantarum 177, e70171. doi:  10.1111/ppl.70171, PMID: PubMed DOI PMC

Takahashi H., Tabara M., Miyashita S., Sonoda Y., Yoshida T., Takahashi A., et al. (2022). Cucumber mosaic virus infection in Arabidopsis: A conditional mutualistic symbiont? Front. Microbiol. 12. doi:  10.3389/fmicb.2021.770925, PMID: PubMed DOI PMC

Tomitaka Y., Shimomoto Y., Ryang B.-S., Hayashi K., Oki T., Matsuyama M., et al. (2024). Development and application of attenuated plant viruses as biological control agents in Japan. Viruses 16, 517. doi:  10.3390/v16040517, PMID: PubMed DOI PMC

Tyagi H., Rajasubramaniam S., Rajam M. V., Dasgupta I. (2008). RNA interference in rice against rice tungro bacilliform virus results in its decreased accumulation in inoculated rice plants. Transgenic Res. 17, 897–904. doi:  10.1007/s11248-008-9174-7, PMID: PubMed DOI PMC

Uchida K., Sakuta K., Ito A., Moriyama H., Sano T., Suzuki N., et al. (2021). Two novel endornaviruses co-infecting a Phytophthora pathogen of Asparagus officinalis modulate the developmental stages and fungicide sensitivities of the host oomycete. Front. Microbiol. 12. doi:  10.3389/fmicb.2021.633502, PMID: PubMed DOI PMC

Uranga M., Daròs J. A., Brodersen P. (2023). Tools and targets: The dual role of plant viruses in CRISPR/Cas9-mediated genome editing. Plant Genome 16, e20220. doi:  10.1002/tpg2.20220, PMID: PubMed DOI

Urayama S. I., Zhao Y. J., Kuroki M., Fukuhara T., Ohmatsu T., Komatsu K., et al. (2024). Greetings from virologists to mycologists: A review outlining viruses that live in fungi. Mycoscience 65, 1–11. doi:  10.47371/mycosci.2024.01, PMID: PubMed DOI PMC

Villa T. G., Abril A. G., Sánchez S., Cortés P., Álvarez M., Arús P., et al. (2021). Animal and human RNA viruses: Genetic variability and ability to overcome vaccines. Arch. Microbiol. 203, 443–464. doi:  10.1007/s00203-020-02034-8, PMID: PubMed DOI PMC

Voloudakis A. E., Kaldis A., Patil B. L. (2025). RNA-based vaccination of plants for control of viruses. Annu. Rev. Virol. 47, 29–52. doi:  10.1146/annurev-virology-091919, PMID: PubMed DOI

Wagh S. S., Patel M., Desai R., Kulkarni V., Bhatt P., Sharma R., et al. (2025). Small RNA and epigenetic control of plant immunity. Plants 5, 47. doi:  10.3390/plants5040047 DOI

Wang Q., Zhang D., Dai Y. R., Liu C. C. (2024). Efficient tobacco rattle virus-induced gene editing in tomato mediated by the CRISPR/Cas9 system. Biotechnol. J. 19, e2400204. doi:  10.1002/biot.202400204, PMID: PubMed DOI

Woolhouse M. E. J., Adair K., Brierley L. (2013). RNA viruses: A case study of the biology of emerging infectious diseases. Microbiol. Spectr. 1, OH–0012-2012. doi:  10.1128/microbiolspec.OH-0012-2012, PMID: PubMed DOI PMC

Xu P., Chen F., Mannas J. P., et al. (2008). Virus infection improves drought tolerance. New Phytol. 180, 911–921. doi:  10.1111/j.1469-8137.2008.02627.x, PMID: PubMed DOI

Xu X. J., Zhu Q., Jiang S. Y., Li F., Gao R., Chen X., et al. (2021). Development and evaluation of stable sugarcane mosaic virus mild mutants for cross-protection against infection by severe strain. Front. Plant Sci. 12. doi:  10.3389/fpls.2021.788963, PMID: PubMed DOI PMC

Yin K., Han T., Liu G., Chen T., Wang Y., Yu A., et al. (2015). A geminivirus-based guide RNA delivery system for CRISPR/Cas9 mediated plant genome editing. Sci. Rep. 5, 14926. doi:  10.1038/srep14926, PMID: PubMed DOI PMC

Zaidi S. S. A., Mahas S., Vanderschuren H., Mahfouz M. M. (2020). Engineering crops of the future: CRISPR approaches to enhance resistance to biotic and abiotic stresses. Genome Biol. 21, 1–16. doi:  10.1186/s13059-020-02204-y, PMID: PubMed DOI PMC

Zaidi S. S. A., Mansoor S., Mahfouz M. M. (2017). Viral vectors for plant genome engineering. Front. Plant Sci. 8. doi:  10.3389/fpls.2017.00539, PMID: PubMed DOI PMC

Zhang D., Xu F., Wang F., Le L., Pu L. (2024). Synthetic biology and artificial intelligence in crop improvement: Engineering resilience and productivity. Plant Commun. 5, 101220. doi:  10.1016/j.xplc.2024.101220, PMID: PubMed DOI PMC

Zhou C., Zhou Y. (2012). Strategies for viral cross protection in plants. In Methods Mol. Biol. 894, 69–81). doi:  10.1007/978-1-61779-882-5_5, PMID: PubMed DOI

Zhu T., Niu G., Zhang Y., Wang J., Li M., Liu Q., et al. (2023). Host-mediated RNA editing in viruses. Biol. Direct 18, 34. doi:  10.1186/s13062-023-00428-9, PMID: PubMed DOI PMC

Zulfiqar S., Iqbal M., Khan A., Farooq M., Abbas A., Hussain A., et al. (2023). Virus-induced gene silencing (VIGS): A powerful tool for crop improvement and its advancement towards epigenetics. Int. J. Mol. Sci. 24, 5608. doi:  10.3390/ijms24065608, PMID: PubMed DOI PMC