Antibiotics have been identified as a new type of environmental contaminant because of their increased use in farm animal production systems. Those drugs that animals are not absorbed mostly are excreted in the feces and urine and contaminates soils. However, the effects of antibiotics on crop plants are still largely unknown. In this study, we determined the effects of chlortetracycline (CTC), a veterinary drug released into the agricultural field by grazing animals or through manure application, on the growth and physiology of Brassica campestris seedlings. Differently from animals, Brassica campestris seedlings have accumulated 5–10-fold higher CTC during cultivation rather than excretion. Morphologically, CTC delays seed germination and inhibits seedling growth such as shortening primary root length and decreasing chlorophyll level. At the molecular level, CTC accumulation in plants downregulated the expression of superoxide dismutase (SOD) genes and decreased the production of hydrogen peroxide (H2O2). Since H2O2 is one of the signaling components involved in the regulation of root growth, exogenous application of H2O2 partially restored the growth and physiology of CTC-treated seedlings. These results suggest that application of CTC-containing manure or compost to soil delays seed germination and inhibits plant growth.

中文翻译：

---

金霉素通过破坏H ₂ O ₂信号传导而抑制油菜种子发芽和幼苗生长

由于抗生素在农场动物生产系统中的使用增加，因此已被确认为一种新型的环境污染物。那些没有被动物吸收的药物大部分会通过粪便和尿液排出体外，并污染土壤。但是，抗生素对农作物的影响仍然未知。在这项研究中，我们确定了金霉素（CTC）（一种通过放牧动物或施用粪肥释放到农业领域中的兽药）对甘蓝型油菜幼苗生长和生理的影响。与动物不同，甘蓝型油菜幼苗在培养过程中积累了5-10倍的四氯化碳，而不是排泄。从形态上讲，CTC会延迟种子发芽并抑制幼苗生长，例如缩短初生根长度和降低叶绿素水平。在分子水平上，植物中四氯化碳的积累下调了超氧化物歧化酶（SOD）基因的表达，并降低了过氧化氢（H2O2）的产生。由于H2O2是参与调节根系生长的信号传导成分之一，因此外源施用H2O2可部分恢复CTC处理过的幼苗的生长和生理。这些结果表明，向土壤中施用含四氯化碳的肥料或堆肥会延迟种子发芽并抑制植物生长。