Into Parichat, Khunnamwong Pannida, Jindamoragot Sasitorn, Am-In Somjit, Intanoo Wanwilai, Limtong Savitree
Department of Microbiology, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand.
National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology, Development Agency (NSTDA), Pathum Thani 12120, Thailand.
Microorganisms. 2020 Mar 3;8(3):362. doi: 10.3390/microorganisms8030362.
The phylloplane is an important habitat for yeasts and these yeasts may have antagonistic activities against pathogens and could be used as biocontrol agents. To investigate rice phylloplane yeasts, 282 strains were isolated from 89 rice leaf samples and identified as 15 known yeast species in the phylum Ascomycota and 35 known and two potential new species in the phylum Basidiomycota. The majority of rice phylloplane yeasts belonged to the phylum Basidiomycota. The evaluation of antagonistic activities of 83 yeast strains against rice pathogenic fungi , , , and revealed that 14 strains inhibited these pathogens. Among the antagonistic strains, DMKU-RP31, DMKU-RP35 and DMKU-RP25 inhibited all rice pathogens tested, and the production of volatile organic compounds, fungal cell wall degrading enzymes and biofilm were the possible antagonistic mechanisms against all rice pathogens tested in vitro. These yeast strains were evaluated for controlling rice sheath blight caused by in rice plants in the greenhouse and were found to suppress the disease by 60.0-70.3%, whereas 3% validamycin suppressed by 83.8%. Therefore, they have potential for being developed to be used as biocontrol agents for rice sheath blight.
叶表面是酵母菌的重要栖息地，这些酵母菌可能对病原体具有拮抗活性，并可作为生物防治剂。为了研究水稻叶表面酵母菌，从89个水稻叶片样本中分离出282株菌株，鉴定为子囊菌门中的15个已知酵母物种以及担子菌门中的35个已知和2个潜在新物种。大多数水稻叶表面酵母菌属于担子菌门。对83株酵母菌株对水稻致病真菌、、、和的拮抗活性评估表明，有14株菌株抑制了这些病原体。在拮抗菌株中，DMKU-RP31、DMKU-RP35和DMKU-RP25抑制了所有测试的水稻病原体，挥发性有机化合物、真菌细胞壁降解酶的产生和生物膜是体外对所有测试水稻病原体可能的拮抗机制。在温室中对这些酵母菌株防治水稻纹枯病菌引起的水稻纹枯病进行了评估，发现它们能将病害抑制60.0 - 70.3%，而3%的井冈霉素抑制率为83.8%。因此，它们有潜力被开发用作水稻纹枯病的生物防治剂。
