RNAi as an emerging approach to control Fusarium head blight disease and mycotoxin contamination in cereals

Abstract

Fusarium graminearum is a major fungal pathogen of cereals worldwide, causing seedling, stem base and floral diseases, including Fusarium head blight (FHB). In addition to yield and quality losses, FHB contaminates cereal grain with mycotoxins, including deoxynivalenol, which are harmful to human, animal and ecosystem health. Currently, FHB control is only partially effective due to several intractable problems. RNA interference (RNAi) is a natural mechanism that regulates gene expression. RNAi has been exploited in the development of new genomic tools that allow the targeted silencing of genes of interest in many eukaryotes. Host‐induced gene silencing (HIGS) is a transgenic technology used to silence fungal genes in planta during attempted infection and thereby reduces disease levels. HIGS relies on the host plant's ability to produce mobile small interfering RNA molecules, generated from long double‐stranded RNA, which are complementary to targeted fungal genes. These molecules are transferred from the plant to invading fungi via an uncharacterised mechanism, to cause gene silencing. Here, we describe recent advances in RNAi‐mediated control of plant pathogenic fungi, highlighting the key advantages and disadvantages. We then discuss the developments and implications of combining HIGS with other methods of disease control. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

RNA-based disease control as a complementary measure to fight Fusarium fungi through silencing of the azole target Cytochrome P450 Lanosterol C-14 α-Demethylase

“…Possible transfer routes for both mechanisms via vesicles or RNA-transporters are indicated. AGO1 seems to be essential for the RNAi response in Fusarium (Chen et al 2015) FgCYP51B is most important for ergosterol biosynthesis and thus survival of the fungus (Fan et al 2013;Liu et al 2011;Machado et al 2018).…”

GWAS for Fusarium Head Blight Related Traits in Winter Wheat (Triticum Aestivum L.) in an Artificially Warmed Treatment

“…A map-based cloning of Fhb1 was recently published, opening the possibility of direct cloning and use of that gene [19]. Furthermore, techniques such as RNA interference (RNAi) for fungicide development and cultivar resistance are promising approaches to controlling FHB [20]. However, FHB is a quantitative disease, thus an individual QTL approach may not be efficient in controlling this disease, since resistant cultivars have a compilation of major and minor genes that work together to provide resistance.…”

Deoxynivalenol: Masked forms, fate during food processing, and potential biological remedies

“…Importantly, small RNAs can be exchanged between plants and fungi. Accordingly, endogenous Host‐Induced Gene Silencing (HIGS) technology and exogeneous Spray‐Induced Gene Silencing (SIGS) technology have been developed to protect plants from Fusarium and reduce Fusarium mycotoxins (DON, 3‐ADON, 15‐ADON, and nivalenol) contamination preharvest, as reviewed by Majumdar, Rajasekaran, and Cary (2017) and Machado, Brown, Urban, Kanyuka, and Hammond‐Kosack (2018). Mediated by plant, HIGS reduce diseases in plant pathogenic fungi by silencing fungal genes in plant during attempted infection (Figure 7b).…”

“…(a) Association between mycotoxin synthesis and omics and the association between different omics (Garcia et al., 2018). (b) Possible pathways of HIGS (left) and SIGS (right) (Machado et al., 2018) Abbreviation: DCL, Dicer‐like proteins.…”

“…Besides, expected gene blocking effects will not fail because of few sequence mismatching. It is expected to achieve simultaneous control of multiple plant pathogens by single silencing cassette (Machado et al., 2018). RNA interference method is conducive to greatly reducing the use of pesticides, contributing to ecosystem and human health.…”