Phosphite (Phi) is used commercially to manage diseases mainly caused by oomycetes, primarily due to its low cost compared with other fungicides and its persistent control of oomycetous pathogens. We explored the use of Phi in controlling the fungal pathogens
Recent discoveries show that fungi can take up environmental RNA, which can then silence fungal genes through environmental RNA interference. This discovery prompted the development of Spray‐Induced Gene Silencing (SIGS) for plant disease management. In this study, we aimed to determine the efficacy of SIGS across a variety of eukaryotic microbes. We first examined the efficiency of RNA uptake in multiple pathogenic and non‐pathogenic fungi, and an oomycete pathogen. We observed efficient double‐stranded RNA (dsRNA) uptake in the fungal plant pathogens
- Award ID(s):
- 1922642
- NSF-PAR ID:
- 10449961
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Plant Biotechnology Journal
- Volume:
- 19
- Issue:
- 9
- ISSN:
- 1467-7644
- Page Range / eLocation ID:
- p. 1756-1768
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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ABSTRACT One of the most promising tools for the control of fungal plant diseases is spray‐induced gene silencing (SIGS). In SIGS, small interfering RNA (siRNA) or double‐stranded RNA (dsRNA) targeting essential or virulence‐related pathogen genes are exogenously applied to plants and postharvest products to trigger RNA interference (RNAi) of the targeted genes, inhibiting fungal growth and disease. However, SIGS is limited by the unstable nature of RNA under environmental conditions. The use of layered double hydroxide or clay particles as carriers to deliver biologically active dsRNA, a formulation termed BioClay™, can enhance RNA durability on plants, prolonging its activity against pathogens. Here, we demonstrate that dsRNA delivered as BioClay can prolong protection against Botrytis cinerea , a major plant fungal pathogen, on tomato leaves and fruit and on mature chickpea plants. BioClay increased the protection window from 1 to 3 weeks on tomato leaves and from 5 to 10 days on tomato fruits, when compared with naked dsRNA. In flowering chickpea plants, BioClay provided prolonged protection for up to 4 weeks, covering the critical period of poding, whereas naked dsRNA provided limited protection. This research represents a major step forward for the adoption of SIGS as an eco‐friendly alternative to traditional fungicides.more » « less
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Summary SUMOylation as one of the protein post‐translational modifications plays crucial roles in multiple biological processes of eukaryotic organisms.
Botrytis cinerea is a devastating fungal pathogen and capable of infecting plant hosts at low temperature. However, the molecular mechanisms of low‐temperature adaptation are largely unknown in fungi.Combining with biochemical methods and biological analyses, we report that SUMOylation regulates pathogen survival at low temperature and oxidative DNA damage response during infection in
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Our study uncovers the molecular mechanisms of SUMOylation‐mediated low‐temperature survival and oxidative DNA damage tolerance during infection in a devastating fungal pathogen, which provides novel insights into low‐temperature adaptation and pathogenesis for postharvest pathogens as well as new targets for inhibitor invention in disease control.
