摘要：铅作为重金属污染中最严重和危害性较强的元素之一，具有很强的移动性、生物毒性大、容易被植物吸收。本论文研究了150mg/L、300mg/L、450mg/L、600mg/L、800mg/L铅浓度对小麦、玉米种子；100mg/L、200mg/L、300mg/L、400mg/L、500mg/L铅对含羞草种子发芽率、根长以及在种子萌发过程中玉米、小麦种子可溶性糖和蛋白质含量的变化。结果显示：铅浓度在0-300mg/L时促进玉米、小麦种子发芽率和根长，在300mg/L时，分别使萌发率增加近10%、1%。当铅浓度超过300mg/L时抑制种子萌发。在铅浓度150mg/L时的玉米种子可溶性糖含量和铅浓度300mg/L时的玉米种子蛋白质含量最大，分别比对照高近2%和6%；铅浓度超过300mg/L时，开始抑制玉米种子的糖和蛋白质含量。铅浓度450mg/L时的小麦种子可溶性糖含量和铅浓度300mg/L时的小麦种子蛋白质含量最大，分别比对照高近1%和3%；铅浓度超过450mg/L时，玉米种子的糖含量显著下降和蛋白质含量没有明显规律。所以，浓度低于300mg/L的铅对玉米、小麦种子的萌发有不同程度地促进作用，浓度高于300mg/L时，铅胁迫开始抑制玉米、小麦种子的萌发。含羞草种子的萌发率和根长均随铅浓度增加而递减。77546

毕业论文关键字：铅胁迫；玉米；小麦；含羞草；生理指标

Effects of Heavy Metal Lead on Germination and Physiological Indexes of Three Plant Seeds

Abstract：Lead is one of the most serious and harmful elements in heavy metal pollution。 It has strong mobility, biotoxicity and is easy to be absorbed by plants。 In this paper, the effects of 0 ml / L, 150ml / L, 300ml/L, 450ml / L, 600ml/L, 800ml / L lead concentration, wheat and maize seeds were 0 ml/L, 100ml/L, 200ml / The germination rate, root length and the content of soluble sugar and protein in the seeds during the seed germination were studied at 300ml / L, 400ml/L, 500ml/L lead concentration。 The results showed that when the concentration of lead was 0-300ml /L, the germination rate and root length of maize and wheat were increased, and the germination rate was increased by nearly 10% and 1% at 300ml/L。 When the lead concentration exceeds 300ml/L, the seed germination is inhibited。The content of soluble sugar in maize seeds at lead concentration of 150ml/L and the maximum content of maize seed protein at 300ml/L, respectively, were nearly 2% and 6% higher than those in control group。 When the lead concentration exceeds 300 ml/L, the sugar and protein content of maize seeds are inhibited。 When the lead concentration was 450ml/L, the soluble sugar content of wheat seeds was the highest, and when the concentration of lead was 300ml/L, the protein content of wheat seeds was the highest。 They were nearly 1% and 3% higher than the control; When the lead concentration exceeds 450ml/L, the sugar content of maize seeds decreased significantly and the protein content was not obvious。 When the concentration of lead was less than 300ml/L, the germination of maize and wheat seeds was promoted to some extent。 When the concentration was higher than 300ml/L, lead stress began to inhibit the germination of maize and wheat seeds。 The germination rate and root length of the mimosa seed decreased with the increase of lead concentration。

Key words ：Lead stress； maize； wheat； mimosa； physiological indicators

目  录

1 绪论 1

1。1  重金属铅的来源与危害 1

1。2  重金属铅对植物种子的影响 1

1。3 含羞草概述 2

1。4 玉米概述 2

1。5小麦概述 2

1。6　研究意义