Abstract: In artificial intelligentized incubator, rice seedlings of Yuanfengzao, the susceptible cultivar to rice blast (Magnaporthe grisea), were defensively inoculated with 10⁶-10⁸/m² conidia suspension dosage of barnyardgrass (Echinochloa spp.) pathogens Alternaria alternata, Curvularia lunata, Helminthosporium gramineum sp. Echinochloae and Exserohilum monoceras. Challenge inoculations with strong pathogenic races Zhong A1 and Zhong B1 of Magnaporthe grisea were carried out at intervals of 1, 2, 3, 5 and 7 days after defence-inoculation. The lesions on rice leaves of defence-inoculation plants were decreased, and the control efficacy to rice blast was significantly increased compared to the control treatment of spraying 002% Tween 20. Reduced rate of lesions ranged from 35.59% to 80.00%, and the control efficacy ranged from 53.08% to 81.56%. No negative effect on rice seedlings was observed after defence-inoculation with barnyardgrass pathogenic fungi.

Key words: barnyardgrass pathogens, defence-inoculation, rice blast, challenge inoculation, control efficacy

摘要： 用稗草病原菌互格交链孢菌、弯孢菌、禾长蠕孢菌稗草专化型和尖角突脐孢菌在实验室人工智能气候箱防御性接种感稻瘟病的水稻品种原丰早，预接种后1、2、3、5和7 d分别挑战接种强致病力的稻瘟病菌“中A1”和“中B1”小种。结果表明，与对照相比，稗草病原菌防御接种后，稻瘟病病斑数减少，病斑减少率在35.59%~80.00%，病情指数明显降低，防效显著提高，达53.08%~81.56%。稗草病原菌挑战接种后对水稻秧苗无明显副作用。

关键词: 稗草病原菌, 防御性接种, 稻瘟病, 挑战接种, 防治效果