土壤抗生素污染对3种蔬菜种子萌发及根系生长的影响

采用土壤培养试验研究了不同剂量的土霉素、恩诺沙星、磺胺二甲嘧啶和泰乐菌素等4种抗生素对小白菜、萝卜和西红柿等3种蔬菜种子萌发、芽长及根系生长的影响。结果表明,蔬菜种子发芽率、芽长、根长受抗生素的影响与抗生素种类、污染浓度及蔬菜品种等有关,根系伸展是蔬菜萌发期受抗生素毒性影响的敏感指标。抗生素对蔬菜生长各要素的影响程度:根伸展>芽生长>种子发芽率;不同蔬菜对抗生素污染的敏感性:小白菜>萝卜>西红柿;4种抗生素对蔬菜的相对毒性:土霉素>磺胺二甲嘧啶>恩诺沙星>泰乐菌素。粉壤质土壤上生长的蔬菜比粘壤质土壤上生长的蔬菜更易受抗生素影响。研究发现,土壤中两种抗生素共存时其对蔬菜种子萌发、芽长、根伸展的影响明显大于单一抗生素污染。

Effects of Soil Antibiotics Pollution on Seed Germination and Root Elongation of Three Kinds of Vegetables

A soil culture experiment was carried out to evaluate the effects of four kinds of antibiotics （ oxytetracycline, enro- floxaein, sulfadimidine and tylosin） at different concentrations on the seed germination, bud length and root elongation of three vege- table species, including Chinese cabbage （ Brassica chinensis L. ）, radish （ Raphanus sativus） and tomato （ Lycopersicon esculentum Mill）. The results showed that the effects of antibiotics on the seed germination, bud length and root elongation of vegetables were related to the concentration and type of antibiotics, and plant species. At germination stage of vegetables, root elongation was the most sensitive to antibiotics as compared with bud length and seed emergence rate. Chinese cabbage was the most sensitive to antibi- otics, followed by radish and then tomato. The eco - toxicity of four kinds of antibiotics to vegetables exhibited the following order ： oxytetracyeline 〉 sulfadimidine 〉 enrofloxacin 〉 tylosin. The effects of four antibiotics on vegetable crops growing in silty - loamy soil were greater than those growing in clayey - loamy soil. It was found that the combined pollution of two antibiotics in soil had ob- viously greater impacts on the seed germination, bud length and root elongation of vegetables than the pollution of single antibiotic.