Biocontrol study of cabbage black rot

• Main Authors: Yun-Ting Ou, 歐昀庭
• Other Authors: 陳昭瑩
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/18496994951473074208

碩士 === 國立臺灣大學 === 植物病理與微生物學研究所 === 101 === Reduced production of cabbages caused by black rot has been a problem difficult to solve. In this study, biocontrol method as an alternative besides the present disease control measures was investigated to reduce the economic loss caused by cabbage black rot. At beginning, induced systemic resistance (ISR) of plants was used as a main screening index of potential biocontrol agents. In combination with the results of seedling growth, strains 28-5, AA2-3, 37-1 and M-2 showed good potentials for application. Field trial with these four strains showed that strain 37-1 had the best biocontrol activity according to the external and internal symptoms. On the other hand, strain 37-1 exhibited superior activity in foliar protection. Thus, the properties of ISR and foliar protection of strain 37-1 were further investigated, including the suitable concentration of application. In the aspect of disease development, disease severity of the plants pre-drenched with strain 37-1 were significantly reduced at 12 days after pathogen inoculation as compared with the control without bacterization. In addition, the pathogen populations in cabbage leaves fluctuated at 7 and 9 days post pathogen inoculation following drench application of strain 37-1. The examination of callose deposition on hydathode areas at leaf margin indicated the seedlings of cabbage drenched with strain 37-1 had defense reaction as compared with the control at 5 days after pathogen inoculation. Thus, drench application of strain 37-1 could suppress symptom development of cabbage black rot by a mechanism of ISR.