Gibberellin-mediated pathogenicity of the rice bakanae pathogen Fusarium fujikuroi

2014 Fiscal Year Final Research Report

• Project/Area Number: 25660035
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Plant protection science
• Research Institution: Nagoya University
• Principal Investigator: TSUGE Takashi 名古屋大学, 生命農学研究科, 教授 (30192644)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: イネばか苗病菌 / ジベレリン / 病原性 / 内生菌

Outline of Final Research Achievements

The rice bakanae pathogen, Fisarium fujikuroi, produces gibberellin (mainly GA3) and causes overgrowth (bakanae) symptom in rice seedlings. GA4 and GA7, the intermediates in GA3 biosynthesis of F. fujikuroi, show higher plant hormone activity than GA3. We made F. fujikuroi mutants, which mainly produce GA4 or GA7, by the disruption of GA biosynthetic genes des or P450-3, respectively. The both mutants caused bakanae symptom more severely than the wild type, indicating that these genes act to reduce virulence of this pathogen. We found F. fujikuroi isolates, which produced GA3 and caused bakanae symptom in rice seedlings, from endophytic isolates collected from healthy tomato plant tissues. This result suggests that the rice bakanae fungus can infect plants other than rice.

Free Research Field

植物病理学