The impact of spray-induced gene silencing on cereal phyllosphere microbiota

Abstract

BackgroundFusarium head blight (FHB) is a major disease affecting cereal crops including wheat, barley, rye, oats and maize. Its predominant causal agent is the ascomycete fungus Fusarium graminearum, which infects the spikes and thereby reduces grain yield and quality. The frequency and severity of FHB epidemics has increased in recent years, threatening global food security. Spray-induced gene silencing (SIGS) is an alternative technique for tackling this devastating disease through foliar spraying with exogenous double-stranded RNA (dsRNA) to silence specific pathogen genes via RNA interference. This has the advantage of avoiding transgenic approaches, but several aspects of the technology require further development to make it a viable field-level management tool. One such existing knowledge gap is how dsRNA spraying affects the microbiota of the host plants.ResultsWe found that the diversity, structure and composition of the bacterial microbiota are subject to changes depending on dsRNA targeted and host studied, while the fungal microbiota in the phyllosphere remained relatively unchanged upon spraying with dsRNA. Analyses of fungal co-occurrence patterns also showed that F. graminearum established itself among the fungal communities through negative interactions with neighbouring fungi. Through these analyses, we have also found bacterial and fungal genera ubiquitous in the phyllosphere, irrespective of dsRNA treatment. These results suggest that although rarer and less abundant microbial species change upon dsRNA spray, the ubiquitous bacterial and fungal components of the phyllosphere in wheat and barley remain unchanged.ConclusionWe show for the first time the effects of exogenous dsRNA spraying on bacterial and fungal communities in the wheat and barley phyllospheres using a high-throughput amplicon sequencing approach. The results obtained further validate the safety and target-specificity of SIGS and emphasize its potential as an environmentally friendly option for managing Fusarium head blight in wheat and barley.

Keywords

Microbiome; Amplicon sequence variants (ASVs); Fusarium graminearum; Spray induced gene silencing (SIGS); Double-stranded RNA (dsRNA); Phyllosphere; Wheat; Barley

Published in

Environmental Microbiome
2025, volume: 20, number: 1, article number: 1
Publisher: BMC

SLU Authors

• Sundararajan, Poorva

  • Department of Plant Breeding, Swedish University of Agricultural Sciences
    

• Ghosh, Samrat

  • Department of Plant Breeding, Swedish University of Agricultural Sciences
    

• Kelbessa, Bekele Gelena

  • Department of Plant Breeding, Swedish University of Agricultural Sciences
    

• Dubey, Mukesh

  • Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
    

• Chawade, Aakash

  • Department of Plant Breeding, Swedish University of Agricultural Sciences
    

• Vetukuri, Ramesh

  • Department of Plant Breeding, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Microbiology
Agricultural Science

Publication identifier

• DOI: https://doi.org/10.1186/s40793-024-00660-8

Permanent link to this page (URI)

https://res.slu.se/id/publ/140187