【作者】 梁程；

【导师】 林匡飞；

【作者基本信息】 华东理工大学 ， 环境科学与工程， 2012， 硕士

【摘要】 水稻作为亚洲地区主要粮食作物,在农业生产中占有重要地位。但是随着工业的发展,环境污染日益严重,重金属污染中尤其是镉污染不容忽视。镉为非营养元素,对植物具有明显的毒害作用,而且会通过食物链危及人体健康。如何缓解或者抑制植物镉的毒害,已经引起了人们的广泛关注。本试验以淮稻6号为材料,采用水培的方法,研究了不同硫(S)浓度下(9mg·L-1、720mg·L-1)硒(Se)(5 mg·L-1)和镉(Cd)(1mg·L-1、10mg·L-1)交互胁迫对水稻幼苗的一些生理特性影响,实验中主要研究指标包括生物量、巯基物质含量和硒镉含量。实验研究结果表明：(1)Cd对水稻幼苗各部分生长状况抑制能力大小不同,其中Cd对根长的抑制作用明显大于对茎长的抑制；(2)在硒镉实验中,在无Se条件下,随着Cd浓度的增加,Cd对水稻幼苗的生长毒性不断增大,在加入一定浓度的Se后,Cd的毒性作用得到缓解；(3)在不同浓度S处理和Se、Cd交互实验下,随着S浓度增大,Cd对水稻幼苗毒性作用减轻；但高浓度的S处理反而对Cd与Se交互实验中的Cd毒性产生协同作用；(4)高浓度的S处理可以抑制水稻幼苗对Se的吸收；(5)巯基物质含量随着胁迫时间的增加呈先上升后下降的趋势。在Se、Cd交互实验中,低浓度S处理可以促进水稻幼苗中的GSH和PCs含量,从而提高植株体内重金属和PC的络合作用,缓减Cd对水稻幼苗的毒害。更多还原

【Abstract】 Rice as main food in Asia areas plays an important role in daily agricultural production of human being. However, with the industrial development, environmental pollution is being more and more serious, such as heavy metals (especially cadmium) pollution. Cadmium, a non-nutrients element, has significant toxic effects on plant, which will endanger man’s health through the food chain. How to ease or inhibit the cadmium poisoning in plant, has attracted widespread attention.To better understand the interactions between sulfate and selenium in plant response to cadmium stress, changes in plant growth and the content of non-protein thiols (NPT, GSH, PC) were investigated in No.6 Huai rice seedlings grown hydroponically with Cd, with or without applications of sulfate and selenium. Results of the study are as followed:(1) The inhibition effects on different parts of rice are various. Results indicated that the inhibition of Cd on the root length was significantly greater than the inhibition of stem length;(2) In the absence of Se treatment, Cd toxicity on the growth of rice seedlings increased with the enhancement of Cd content in plant. The addition of Se treatment could significantly increased the plant growth;(3) In the Cd, Se and S combination experiments, Cd toxicity to rice seedlings reduced with alleviation content of S in plant. However, A combination of Se(5 mg·L-1)-S(720 mg·L-1) treatment led to a decrease of rice plants mass;(4) High concentrations of S treatment can inhibit the absorption of Se in rice seedlings;(5) The content of non-protein thiols in rice seedlings fist increased and then decreased during the exposure time. In the Cd, Se and S combination experiments, the contents of GSH and PCs enhanced with low concentration of S addition in plant, which promoted the complexation between Cd and non-protein thiols for decreasing the Cd toxicity in rice growth.更多还原