News Release

Fungus has a host of issues

KyotoU discovers how toxic fungi target specific host plants 

Peer-Reviewed Publication

Kyoto University

Host specificity of phytopathogenic fungus

image: Cucumber leaf, along with melon and tenth, are studied for the effector proteins EPC1 to EPC4. view more 

Credit: KyotoU Tobiyama/Yoshitaka Takano

Kyoto, Japan -- While infectious fungal plant diseases relentlessly wreak havoc on many crops, they are also picky when choosing their hosts. Each fungus generally exhibits a specific host range, but the mechanism of this specificity has not been well understood.

Kyoto University researchers have now identified and categorized four fungal proteins called effectors responsible for suppressing host plant immunity from infection.

Phytopathogens are plant pathogenic fungi that secrete these effectors. As a result, the harmful fungus generally exhibits distinct host specificity when infecting plants, causing more than 70% of plant diseases.

According to the researchers, the four effector proteins named EPC1 to EPC4 in Colletotrichum orbiculare -- a phytopathogenic fungus -- establish specificity on a host cucumber. 

"The four effectors have very different amino acid sequences, suggesting that they work independently, but we need to continue analyzing the function of each effector to get a clearer picture," says lead author Yoshitaka Takano of KyotoU's Graduate School of Agriculture.

Takano's team used functional analysis -- targeted gene disruption -- on effector-like genes, which are highly expressed in six isolates of the inoculated pathogen. 

"We have just cracked open a peephole to understand how effectors of phytopathogenic fungi shape host specificity. Our growing knowledge may lead to new crop protection technologies."


The paper "Selective deployment of virulence effectors correlates with host specificity in a fungal plant pathogen" appeared on 20 March 2023 in New Phytologist, with doi: 10.1111/nph.18790

About Kyoto University

Kyoto University is one of Japan and Asia's premier research institutions, founded in 1897 and responsible for producing numerous Nobel laureates and winners of other prestigious international prizes. A broad curriculum across the arts and sciences at undergraduate and graduate levels complements several research centers, facilities, and offices around Japan and the world. For more information, please see:

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.