碩士 / 國立中興大學 / 植物病理學研究所 / 82 / Bacterial soft rot of colored calla lily a very serious disese in Taiwan. The disease incidence may reach high to 50%in the field. In the study, a total of 26 strains of soft rot Erwinia were isolated from rotted tissues collected from colcred calla lily grown fields in Houli, Wujih and Cholan. Based on the physiological and biochemical tests, 19 strains were identified as Erwinia carotovora subsp. carotovora, while the other 7 strains were Erwinin chrysanthemi with phenotypic characteristics similar to the strains in the subdivision Ⅱ and biovar 6 according to the Dickey''s and Boccara''s classification systems. The results of maceration tests showed that strains of both of Erwinia carotovora subsp. carotovora and Erwinia chrysanthemi isolated from colored calla lilly were more virulent than strains of Erwinia carotovora subsp. carotovora isolated from other crops on the rhizome slices of colored calla lily. Among 5 cultivars of colored calla lily tested, the cultivars Best Gold and Tango with golden and orange flowers, repectively, were the most susceptible, while little Suzy with pink flowers was the least susceptible, to Erwinia carotovora subsp. carotovora and Erwinia chrysanthemi. When rhizome slices of colored calla lily were coinoculated with cell suspensions of both E. carotovora subsp. carotovora and E. chrysanthemi in 1:1 ratio,E. chrysanthemi was dominant in the rotted tissues at higher temperature (24~37°C) ,while E. carotovora subsp. carotovora was dominate at lower temperatuer (16°C). In the copper and streptomycin tests, most strains of E. carotovora subsp. carotovora and E.chrysanthemi were resistant to CuSO4. 5H2O at the concerntration of 500∼600 ppm, but were sensitive to streptomycin sulfate (≧50ppm). In addition, most strains were resistant to commercial formulated agrochemicals containing copper, but the growth of most strains was inhibited by the formulated agrochemicals containing streptomycin. Rhizomes of colored calla lily obtained from differeint sources were tested for the percentage of soft rot Erwinia, that results showed that 20∼70% rhizomes were contaminated with soft not Erwinia Treatments of rhizome with 50°C hot water and hot acidified zinc sulfate reduced the popuolation of soft rot Erwinia on the surfae of rhozomes. Howere, it was apparent that the treatment with hot acidified zinc sulfate was more effective. No adverse effects were observed on emergence of rhizomes, plant height and days to flowering when rhizomes of colored calla lily were treated with hot acidified zinc sulfate. Among 11weed species tested, E. carotovora subsp. carotovora was detected in selective CVP medium after enrichment, in rhizosphere soil from 5 weed species, while E. chrysanthemi was detected in 6 weed specties. Addition of cabbage leaf chips to autoclaved or non-autocalved soil accelerated the decline of the population of soft rot Erwinia in soil. In green house test, population of E. carotovora subsp. carotovora surived longer in colored calla lily rhizosphere soil than in non-rhizosphere soil.
| Identifer | oai:union.ndltd.org:TW/082NTPU3363008 |
| Date | January 1994 |
| Creators | Li, Y. Y., 李一芸 |
| Contributors | Tzeng, K. C., 曾國欽 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 63 |
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