High Humidity Causes Abnormalities in the Process of Appressorial Formation of Blumeria graminis f. sp. hordei

• Published in: Pathogens (Basel) Vol. 9; no. 1; p. 45
• Main Authors: Sugai, Koreyuki, Inoue, Hiroshi, Inoue, Chie, Sato, Mayuko, Wakazaki, Mayumi, Kobayashi, Kappei, Nishiguchi, Masamichi, Toyooka, Kiminori, Yamaoka, Naoto, Yaeno, Takashi
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 05-01-2020; MDPI
• Subjects: Abnormalities; Airborne microorganisms; appressorium; Blumeria graminis; blumeria graminis f. sp. hordei; Cellulose; Conidia; hordeum vulgare; Humidity; Humidity control; Infections; Influence; Membranes; Moisture control; Morphogenesis; Powdery mildew; Proteins; Blumeria graminis f. sp. hordei; appressorium; humidity; Hordeum vulgare
• ISSN: 2076-0817; 2076-0817
• DOI: 10.3390/pathogens9010045

High humidity decreases the penetration rate of barley powdery mildew
f. sp.
. However, the mechanism is not well understood. In this study, the morphological and cytochemical analyses revealed that substances containing proteins leaked from the tip of the appressorial germ tube of conidia without the formation of appressorium under a high humidity condition. In addition, exposure to high humidity prior to the formation of appressorium caused the aberrant formation of the appressorial germ tube without appressorium formation, resulting in failure to penetrate the host cell. These findings suggest that the formation and maturation of the appressorium requires a low humidity condition, and will be clues to improve the disease management by humidity control.