蚕豆油壶菌火肿病的发生规律

【目的】研究蚕豆火肿病在四川的地理分布、病害循环及影响发病的因素,从而掌握该病的发生规律。【方法】通过病害普查,确定蚕豆火肿病的地理分布。采用室内测定研究温度和越冬对休眠孢子囊萌发的影响。进行田间试验,调查病害发生情况,研究病害循环和影响病害发生的因素。【结果】蚕豆火肿病在四川的地理分布局限在川西北阿坝州海拔2 400m以上的春播蚕豆区。病害的循环和发病特点是:病菌以病残体中的休眠孢子囊,在土壤中休眠(越夏和越冬),作为初侵染源。次年春播蚕豆后,休眠孢子囊萌发产生游动孢子侵染蚕豆苗。田间发病后,病菌不断产生游动孢子囊,释放游动孢子作为再侵染源,病菌的再侵染频繁。游动孢子藉风雨在田间短距离传播。病害的发生流行曲线呈"S"型。连作和施用带病残体的厩肥有利发病。尚无对火肿病的抗病品种。【结论】这些结果揭示了蚕豆火肿病的发生规律,为该病的防治提供了科学依据。

On the Occurrence Regularity of Broad Bean Blister

【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.