Inoculum Sources and Host Range of Black Rot of Wasabi Caused by Phoma wasabiae

山葵黑心病感染源與寄主範圍之探討

羅朝村(Chaur-Tsuen Lo) ； 王貴美(Kuei-Mai Wang)

《植物病理學會刊》 10卷2期 (2001/06) Pp. 88-92

https://doi.org/10.6649/PPB.200106_10(2).0005

摘要

本研究主在探討山葵黑心病菌可能危害山葵之主要感染源，以明瞭山葵黑心病菌在田間發生擴展之情形；在測試之山葵植株中，發現山葵黑心病主要感染源來自於農民慣用之分孽苗；依據調查結果來自於母株根莖之分孽苗及根苗帶菌率分別為67-90%及17-50%。其他結果亦顯示在測試之二十八植物中，山葵黑心病菌可感染包括山芋、綠竹、山苧麻、蘿蔔、羊蹄、冇骨消等植物，亦即山葵黑心病菌除可感染山葵以外，尚可感染臨近或山葵田中之作物與雜草而成為當期栽培山葵之二次感染源或另一季的初次感染源。另外從測試柄子殼及柄孢子在土壤存活與病害發生之情形，發現含有二者之土壤，需經三個月以上才不會造成根莖黑心病，因此收穫後含有柄子殼或柄孢子之土壤，亦可能是另一季的初次感染源之一。從以上之結果說明減少初次感染源如利用無病苗等將是防治山葵黑心病的必要步驟。

關鍵字

山葵黑心病菌 ； 山葵 ； 感染源 ； 根莖

並列摘要

The significance of vegetative propagation as a source of primary inoculum in spread of black rot (or streak disease), caused by Phoma wasabiae, was investigated in this study. In tested samples of wasabi plants, 67-90% of the rhizome-tillers and 17-50% of root-plantlets were infected by P. wasabiae that spread mainly from infected parent plants to their progeny, tillers and root-plantlets . Results also indicated that six species among 28 tested plants including common weeds also play an important role on initial source. These six species plants grown in/near the wasabi fields were Alocasia macrorryhiza, Bambusa oldhamic, Raphanus sativus, Boehmeria frutesccus var. concolor, Rumex japonicus, and Sambucus takasagoensis. Both pycnidia and pycnidiospores of P. wasabiae in soils remained infective to the wasabi plant for only a short period of 3 months. Results of this study suggest that wasabi plantings should begin with pathogen-free planting materials to control the disease. In old diseased field, destruction of common weeds and fallow for several months before planting are also essential.

並列關鍵字

wasabi ； Phoma wasabiae ； inoculum source ； rhizome