尖角突脐孢菌在温室环境下侵染稗草的致病体系研究

稗属（Echinochloa）杂草是全世界水稻等作物生产中的一类恶性杂草。人工除稗安全但费时费力，化学除稗高效但伴随农产品安全和环境相融友好方面的潜在风险。因此，寻求安全高效的除稗活性成分和施药技术成为国际上除稗剂发展的重要方向之一。在研究和开发生物除稗剂的技术体系中，满足高通量筛选安全、高效的除稗生防因子的温室检测体系是极为重要的支持平台，同样，生物除稗剂的田间科学施药技术亦应依据生防因子在稗草上致病和致害所需的最佳条件来制定。基于此，亟需探明生防因子侵染稗草致病的相关条件并建立快速有效的生防因子除稗效果温室检测体系和田间施药技术。本文系统研究了影响尖角突脐孢菌侵染稗草的相关因子，建立了稳定的温室环境下尖角突脐孢菌侵染稗草的致病体系。

Pathogenicity system of Exserohilum monoceras to barnyardgrass in greenhouse

The effects of inoculum concentration, leaf stages of host plant, and environmental factors on the infection of Exserohilum monoceras isolate X-27 to barnyardgrass were investigated. The results showed that the lesion was visibly appeared on the leaf when inoculum concentration above 1.00×10⁵ conidia mL-1, 1-2 leaf stage of barnyardgrass was most sensitive for infection of E. monoceras. The data also indicated that dew period was the key factor for E. monoceras infection. Almost 90% of barnyardgrass plants were killed when dew period prolonged to 48 h. Temperature and illumination period did not significantly affect the infec-tion of E. monoceras, 25-28℃ and 12 h dark period after inoculation were enough for infection.