The Characteristics of Pseudomonas syringae from Carambola

• Main Authors: Ku-Ting Chen, 陳谷婷
• Other Authors: Shih-Tien Hsu
• Format: Others
• Language: zh-TW
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/54623957755649193219

碩士 === 國立中興大學 === 植物病理學系 === 88 === Bacterial spot is a new disease of carambola in Taiwan. The typical symptoms on leaves are purple spots surrounded by yellow haloes, and the infected leaves turn yellow and fall easily. The pathogen isolated from diseased tissues produced fluorescent pigment on King’s B medium. Based on physiological characteristics, the pathogen was identified as a strain of Pseudomonas syringae. The analysis by the system of Biolog GN Microplate showed that the pathogen had higher similarity with P. syringae pv. pisi（0.407-0.782）, or was more closely related to P. syringae pv. syringae（0.541-0.810）. But there were no symptoms appeared when the known pv. pisi and pv. syringae were inoculated to carambola. The pathogen could infect carambola cultivars Malaysia、Tsen Tsway、Erh Lin Juan Chih、and Sour. When a specific syringomycin gene fragment was detected by polymerase chain reaction（PCR）with primer pair syD1/syD2, only the reference strain of P. syringae pv. syringae produced the specific fragment, but carambola strains didn’t. A specific ethylene-forming enzyme gene fragment was not amplified from carambola strains by PCR. However, small amounts（0.03-20.92 ppm/hr—5ml culture）of ethylene were detected from the cultures of carambola strains of P. syringae grown in liquid 523 medium by gas chromatograph. Inoculation of carambola strains to soybean、pea、kidney bean、cowpea、tobacco、tomato、cabbage、cucumber、jack fruit、mulberry、persimmon、guava、wax-apple、longan、litchi、peach、plum、prune、loquat、pear、buntan shaddock、grapefruit pomelo、lemon、mandarin orange、ping pong、sugar apple、sapodilla、passion fruit、olive、mango、and grapefruit did not produce any symptoms. The carambola strains were only pathogenic to carambola. The results indicated that carambola strains belong to Pseudomonas syringae, and they may be a new pathovar of Pseudomonas syringae.