Geological Survey of Denmark and Greenland (GEUS), DK-1350 Copenhagen, Denmark.
Appl Environ Microbiol. 2010 Feb;76(3):710-4. doi: 10.1128/AEM.00615-09. Epub 2009 Dec 18.
A leaching experiment, where liquid manure spiked with Salmonella enterica serovar Typhimurium (Tet(+)) DSM554 was applied to soil surfaces, was conducted on intact soil monoliths (60 cm in diameter and 100 cm long). A total of 6.5 x 10(10) CFU was applied to each column. We found that Salmonella serovar Typhimurium could be transported to a 1-m depth in loamy soil at concentrations reaching 1.3 x 10(5) CFU/ml of leachate. The test strain was found in concentrations ranging from 300 to 1.3(5) cells/ml in loamy soil throughout the 27 days of the experiment, while concentrations below 20 cells/ml were sporadically detected in the leachates from sandy monoliths. Real-time PCR targeting invA DNA showed a clear correspondence between the total and culturable numbers of cells in the leachate, indicating that most cells leached were viable. On day 28, distribution of Salmonella serovar Typhimurium at five depths in the four monoliths was determined. The highest recovery rate, ranging from 1.5% to 3.8% of the total applied inoculum, was found in the top 0.2 m.
进行了一项淋滤实验，在完整的土壤单体（直径 60 厘米，长 100 厘米）上施加了含有肠炎沙门氏菌血清型 Typhimurium（Tet(+)）DSM554 的液体肥料。每个柱体施加了 6.5 x 10(10) CFU。我们发现，肠炎沙门氏菌血清型 Typhimurium 可以在壤土中被运移到 1 米的深度，浓度达到 1.3 x 10(5) CFU/ml 的淋出液。在实验的 27 天中，在壤土中发现测试菌株的浓度范围为 300 至 1.3(5)细胞/ml，而在沙质单体的淋出液中偶尔检测到浓度低于 20 细胞/ml 的菌株。针对 invA DNA 的实时 PCR 显示，淋出液中总细胞数和可培养细胞数之间存在明显的对应关系，表明淋出的大多数细胞都是有活力的。在第 28 天，在四个单体的五个深度处确定了肠炎沙门氏菌血清型 Typhimurium 的分布情况。在顶部 0.2 米处发现了最高的回收率，范围从总接种量的 1.5%到 3.8%。
