Effect of flutianil on the morphology and gene expression of powdery mildew

Sachi Kimura; Yusuke Shibata; Takao Oi; Kazuhito Kawakita; Daigo Takemoto

doi:10.1584/jpestics.D21-003

Effect of flutianil on the morphology and gene expression of powdery mildew

J Pestic Sci. 2021 May 20;46(2):206-213. doi: 10.1584/jpestics.D21-003.

Authors

Sachi Kimura¹, Yusuke Shibata², Takao Oi², Kazuhito Kawakita², Daigo Takemoto²

Affiliations

¹ Research and Development Division, OAT Agrio Co., Ltd., Tokushima, Japan.
² Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa, Nagoya, 464-8601, Japan.

Abstract

Flutianil, a fungicide effective only on powdery mildew, was previously reported to affect the host cell's haustorial formation and nutrient absorption. Studies were conducted to investigate flutianil's primary site of action on Blumeria graminis morphology using transmission electron microscope (TEM) observation and RNA sequencing (RAN-seq) techniques. TEM observation revealed that flutianil caused the extra-haustorial matrix and fungal cell wall to be obscured, without remarkable changes of other fungal organelles. RNA-seq analysis indicated that, unlike other powdery-mildew fungicides, flutianil did not significantly affect the constantly expressed genes for the survival of B. graminis. Genes whose expression is up- or downregulated by flutianil were found; these are the three sugar transporter genes and various effector genes, mainly expressed in haustoria. These findings indicate that the primary site of action of flutianil might be in the haustoria.

Keywords: Blumeria graminis; RNA-seq; flutianil; haustorium; microscopy; powdery mildew; ultrastructure.

© Pesticide Science Society of Japan 2021. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) License (https://creativecommons.org/licenses/by-nc-nd/4.0/).