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Title: Spray‐induced gene silencing to identify powdery mildew gene targets and processes for powdery mildew control
Abstract Spray‐induced gene silencing (SIGS) is an emerging tool for crop pest protection. It utilizes exogenously applied double‐stranded RNA to specifically reduce pest target gene expression using endogenous RNA interference machinery. In this study, SIGS methods were developed and optimized for powdery mildew fungi, which are widespread obligate biotrophic fungi that infect agricultural crops, using the known azole‐fungicide targetcytochrome P45051 (CYP51) in theGolovinomyces orontii–Arabidopsis thalianapathosystem. Additional screening resulted in the identification of conserved gene targets and processes important to powdery mildew proliferation:apoptosis‐antagonizing transcription factorin essential cellular metabolism and stress response; lipid catabolism geneslipase a,lipase 1, andacetyl‐CoA oxidasein energy production;and genes involved in manipulation of the plant host via abscisic acid metabolism (9‐cis‐epoxycarotenoid dioxygenase,xanthoxin dehydrogenase, and a putativeabscisic acid G‐protein coupled receptor) and secretion of the effector protein,effector candidate 2. Powdery mildew is the dominant disease impacting grapes and extensive powdery mildew resistance to applied fungicides has been reported. We therefore developed SIGS for theErysiphe necator–Vitis viniferasystem and tested six successful targets identified using theG. orontii–A. thalianasystem. For all targets tested, a similar reduction in powdery mildew disease was observed between systems. This indicates screening of broadly conserved targets in theG. orontii–A. thalianapathosystem identifies targets and processes for the successful control of other powdery mildew fungi. The efficacy of SIGS on powdery mildew fungi makes SIGS an exciting prospect for commercial powdery mildew control.  more » « less
Award ID(s):
2122944
PAR ID:
10508750
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Molecular Plant Pathology
Volume:
24
Issue:
9
ISSN:
1464-6722
Page Range / eLocation ID:
1168 to 1183
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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