Sundararajan, Poorva
- Institutionen för växtförädling, Sveriges lantbruksuniversitet
Sammanfattning
Triticum aestivum L. (wheat), Hordeum vulgare L. (barley) and Solanum tuberosum (potato) are major crops contributing to primary food production and food security worldwide. However, their cultivation is hampered by pathogens and pests. Existing methods for plant protection largely consist of cultural practices, using fungicides, and breeding for resistance and better agronomic traits. Such strategies can be variably successful, tedious, economically strenuous and harmful to human and environmental health. As the search for sustainable alternatives continues, solutions based on RNA interference (RNAi) have emerged as promising alternatives. RNAi is a natural defence mechanism in eukaryotic organisms through which targeted gene silencing leads to transcriptional and post-transcriptional gene regulation. Researchers have exploited RNAi for several applications using its characteristic components – double-stranded RNAs (dsRNA) and small RNAs. In the field of plant protection, RNAi and dsRNA sprays have shown promise for disease control, including the control of pathogens like Fusarium graminearum and Phytophthora infestans. This method of spraying dsRNAs for pathogen control was termed spray-induced gene silencing (SIGS). Despite promising initial results, several facets of SIGS still need development for its adoption for field use. Through this thesis, two such aspects have been addressed: the ability of SIGS to suppress disease under practical conditions and the impact of spraying dsRNA on the plant microbiome. We show that dsRNA targeting F. graminearum can reduce the progression of Fusarium head blight in intact wheat and barley spikes. Using amplicon sequencing, we show for the first time that spraying dsRNA does not alter the core bacterial and fungal constituents of the phyllosphere, while causing minor changes to the relative abundance of bacterial communities in wheat, barley and potato. These studies strengthen the potential of SIGS for managing filamentous phytopathogens and reinforce the target-specific nature of the methodology. Such a holistic understanding of the processes that underlie SIGS-based plant protection therefore enable smooth transition of the technology for large-scale use.
Nyckelord
SIGS; dsRNA; RNAi; Fusarium graminearum; Phytophthora infestans; Fusarium head blight; microbiome; phyllosphere; amplicon sequencing; axfusarios; mikrobiom; fyllosfär; amplikonsekvensering
Publicerad i
Acta Universitatis Agriculturae Sueciae
2026, nummer: 2026:8
Utgivare: Swedish University of Agricultural Sciences
SLU författare
UKÄ forskningsämne
Molekylärbiologi
Växtbioteknologi
Publikationens identifierare
- DOI: https://doi.org/10.54612/a.5e9qg9vui7
- ISBN: 978-91-8124-205-8
- eISBN: 978-91-8124-225-6
Permanent länk till denna sida (URI)
https://res.slu.se/id/publ/145359