Pb污染对白菜的生态毒理效应研究

Ecotoxicological Effects of Pb on Brassice rapa

采用水培方法研究了白菜种子和幼苗对Pb的富集能力与耐受性.实验设6个处理浓度,分别为0.2mg·L-1、0.4mg·L-1、0.8mg·L-1、1.6mg·L-1、3.2mg·L-1及对照,共培养7d,然后测定种子萌发抑制率、茎生长抑制率、根的耐性指数、叶绿素与类胡萝卜素含量与铅的富集量.研究表明白菜幼苗对高浓度的Pb具有富集能力,根是主要的富集器官,根的最高富集量为75.46mg·L-1.Pb抑制白菜幼苗的营养生长,抑制白菜根的伸长.0.2mg·L-1处理浓度下,Pb促进白菜茎的生长,高浓度的Pb抑制白菜茎的生长.Pb抑制白菜体内叶绿素a、叶绿素b和类胡萝卜素的含量.铅影响白菜幼苗的正常生长,白菜对铅具有一定耐受性.

Water culture methods have been used to study Pb enrichment capability and tolerance of Brassice rapa seeds and seedlings.6 concentrations of Pb were set：0.2mg·L-1,0.4mg·L-1,0.8mg·L-1,1.6mg·L-1,3.2mg·L-1 and control.After Brassice rapa seeds cultured in these solution for 7 days,the rate of seed germination,stem growth inhibition rate,root tolerance index,chlorophyll and carotenoid content and the amount of lead concentration were measured.The ability of enrichment and tolerance of Brassice rapa seedlings to Pb studied using the indoor culture technique.The results show that Brassice rapa seedlings had high ability of enrichment to Pb.Roots were main organs of enrichment of Pb.The maximum capacity of the root concentration is 75.46mg·L-1.Pb inhibited Brassice rapa seed germination and seedling growth.With 0.2mg·L-1,Pb promoted the growth of Brassice rapa stems.High concentrations of Pb inhibited the growth of Brassice rapa stem.Pb inhibited the chlorophyll synthesis and Carotenoids and the normal growth of Brassice rapa seedlings.Brassice rapa has a certain tolerance to Pb.