关键词: 蚕豆, 火肿病, 野豌豆油壶菌, 病害循环, 病害流行曲线

Abstract: [Objective] The purpose of this study was to investigate the disease(broad bean blister disease) geographical distribution, disease cycle and influence factors on disease development, so that understand the occurrence regularity of the disease. [Method] Wide survey of broad bean blister was undertaken to determine the distribution of the disease. Laboratory assay was used to test the effect of temperature and overwinter on germination of resting sporangia. Field trails were conducted to study the disease cycle and epidemical factors. [Results] The geographical distribution of broad bean blister, caused by Olpidium viciaen was limited in ecological zone above 2 400 m altitude suitable for spring sowing broad bean, of Aba Autonomous region, Northwestern Plateau of Sichuan province. The disease cycle and developmental characteristics of the disease were as follows:the resting sporangia of O. viciae survived and rested(oversummer and overwinter) on disease plant debris in field soil as the initial infection sources. After sowing seeds of broad bean in spring the resting sporangia germinated and produced zoospores. The zoospores infected seedling of broad bean. After the disease occurred in field, zoosporangia constantly produced on infected plant tissues and liberated zoospores as a reinfection source. The zoospores were dispersed by the air and water splash in short distance. The frequency of reinfection by the pathogen was very highly. The disease epidemic curve was "S" type. Continuous cropping and application of animal manure with infected plant debris increased incidence of the disease. No resistant variety was found. [Conclusion] These results demonstrated the occurrence regularity of broad bean blister, and provided scientific base for controlling the disease.

Key words: broad bean, blister disease, Olpidium viciae, disease cycle, disease epidemic curve