Kinkel L L, Bowers J H, Shimizu K, Neeno-Eckwall E C, Schottel J L
Department of Plant Pathology, University of Minnesota, Saint Paul 55108, USA.
Can J Microbiol. 1998 Aug;44(8):768-76.
Thaxtomin A production in culture, potato common scab severity (percentage of tuber surface infected or number of lesions per tuber), and fatty acid profiles were determined for 78 Streptomyces isolates. Only pathogenic Streptomyces spp. (n = 17) produced thaxtomin A in culture. Thaxtomin A production in culture (microgram/mL) was significantly positively correlated with the percentage of tuber surface infected (R = 0.60; p = 0.017) but not with the number of lesions per tuber (R = 0.37; p = 0.17). An increase of 1 microgram/mL in thaxtomin A production corresponded to an 11% increase in disease severity (percentage of tuber surface infected). The data indicate that quantitative information on the ability of a particular pathogen isolate or population to produce thaxtomin A may be critical to understanding and predicting the disease potential of that population. Using cluster analysis of fatty acid data, 94% of 67 unknown field isolates grouped with other field isolates having the same pathogenicity (plus or minus).
对78株链霉菌分离株测定了其在培养物中毒胡萝卜素A的产量、马铃薯疮痂病严重程度（块茎表面感染百分比或每个块茎的病斑数）以及脂肪酸谱。只有致病性链霉菌属（n = 17）在培养物中产生毒胡萝卜素A。培养物中毒胡萝卜素A的产量（微克/毫升）与块茎表面感染百分比显著正相关（R = 0.60；p = 0.017），但与每个块茎的病斑数无关（R = 0.37；p = 0.17）。毒胡萝卜素A产量每增加1微克/毫升，疾病严重程度（块茎表面感染百分比）就增加11%。数据表明，关于特定病原菌分离株或群体产生毒胡萝卜素A能力的定量信息对于理解和预测该群体的致病潜力可能至关重要。通过对脂肪酸数据进行聚类分析，67株未知田间分离株中有94%与其他具有相同致病性（阳性或阴性）的田间分离株归为一组。
