砷和草甘膦复合污染对水稻生长的影响及其机理研究

发布时间：2018-07-01 20:42

本文选题：水稻 + 砷　；参考：《华中农业大学》2015年硕士论文

【摘要】：水稻是我国主要的粮食作物。水稻对砷具有比其他作物更强的吸收能力,砷在水稻中的富集不仅会导致水稻的减产,而且砷在水稻秸秆和籽粒中的积累会通过食物链传递,对人和牲畜造成健康风险。草甘膦是目前使用广泛的除草剂,草甘膦在土壤中的残留以及对作物的危害一直是农业生产中的热点问题。探讨砷和草甘膦复合污染条件下水稻的生长发育状况,对于了解重金属和除草剂污染和残留对水稻种植的影响有十分重要的意义。本论文研究了不同浓度砷和草甘膦单独及联合处理条件下,水稻的种子萌发、幼苗的生长发育和碳代谢、产量构成、矿质元素累积以及砷的富集和迁移变化,探讨了砷和草甘膦单一及复合污染对水稻生长生育的影响,旨在为掌握重金属和除草剂复合污染对水稻毒害作用提供参考。主要研究结论如下:1.研究了砷(0-20mg/L)和草甘膦处理(0-20mg/L)单一及联合处理对水稻种子萌发的影响,结果表明:砷和草甘膦处理显著抑制了水稻的萌发,降低了水稻种子的发芽率和种子活力、根长和芽长、种子鲜重以及淀粉酶活性和贮藏物质转运率。砷处理对水稻种子萌发率及胚根生长的抑制程度要大于草甘膦,而对胚芽的生长影响小于草甘膦处理。草甘膦和砷复合污染具有协同抑制作用,进一步降低了水稻萌发率、根长和芽长的生长及淀粉酶活性。2.采用溶液培养方法,研究了砷处理(0-5mg/L)和草甘膦处理(0-5mg/L)单一和联合处理对水稻幼苗生物量、抗氧化系统、碳代谢及砷吸收的影响。结果表明:砷和草甘膦都显著抑制了水稻幼苗的生长,降低了水稻株高、叶绿素SPAD值、地上和根的鲜重以及根系活力。砷胁迫降低了水稻幼苗抗氧化胁迫的能力,使MDA含量增加;然而低浓度草甘膦处理提高了水稻抗氧化胁迫的能力、使MDA含量下降,高浓度草甘膦处理则提高了MDA含量。砷和草甘膦联合处理对水稻MDA含量无明显的交互作用。单一处理条件下,1mg/LAs处理降低了、5mg/LAs处理则提高了水稻茎叶中可溶性糖和蔗糖的含量;而草甘膦处理除低浓度(1mg/L)降低了蔗糖含量外,显著提高了水稻茎和叶中可溶性糖和蔗糖的含量。砷和草甘膦处理对水稻SPS酶活性均无显著影响,但高浓度砷和草甘膦处理显著提高了SS酶活性。砷和草甘膦处理对可溶性糖含量和SPS酶活性存在显著交互作用,两者联合处理显著提高了可溶性糖含量、降低了SPS酶活性。高浓度草甘膦(5mg/L)降低了水稻茎叶和根中As的含量。1mg/L As及5mg/L As处理条件下,5mg/L草甘膦处理水稻根和茎叶中砷的含量分别为不施草甘膦处理的55.1%、89.6%(根)和77.5%、84.3%(地上部)。3.采用土壤培养方法,研究了砷处理(0-80mg/L)和草甘膦处理(0-16mg/L)单一及联合处理对水稻生育期进程、产量、矿质营养元素含量及砷的吸收和累积的影响。结果表明:砷和草甘膦处理显著地抑制了水稻的生长,降低了水稻株高和叶绿素含量,推迟了水稻生育期。砷胁迫降低了水稻产量,砷和草甘膦处理具有协同作用,使水稻产量进一步降低。砷胁迫显著降低了水稻植株茎和叶中N、P和K的含量,砷和草甘膦复合污染对分蘖期水稻根和茎中N、P和K的含量有显著交互作用、使分蘖期水稻根和茎中N、P和K的含量进一步下降,但对成熟期水稻植株N、P和K的含量交互作用不显著。砷处理显著提高了成熟期水稻茎叶、谷壳和糙米中Fe和Mn的含量,但降低了Cu和Zn的含量。草甘膦处理则显著降低了成熟期水稻茎叶、谷壳和糙米中Fe和Mn的含量,提高了Zn的含量。砷和草甘膦复合污染对成熟期水稻Fe、Mn、Cu和Zn的含量均存在显著的交互作用。砷处理显著提高了水稻各部分的砷含量。草甘膦促进了分蘖期水稻对砷的吸收,但对抽穗期和成熟期水稻砷含量无显著影响。
[Abstract]:Rice is the main grain crop in China. Rice has a stronger absorption capacity to arsenic than other crops. The enrichment of arsenic in rice will not only lead to the reduction of rice, but also the accumulation of arsenic in rice straw and grain will pass through the food chain and cause health risk to people and livestock. Glyphosate is a widely used herbicide, grass now. The residue of glyphosate in soil and its harm to crops has been a hot issue in agricultural production. It is of great significance to understand the growth and development of rice under the combined pollution of arsenic and glyphosate. It is very important to understand the effect of heavy metals and herbicide pollution and residue on rice planting. The seed germination of rice, the growth and development of the seedlings, the composition of the yield, the accumulation of mineral elements and the accumulation and migration of arsenic, the effects of single and compound pollution of arsenic and Glyphosate on the growth and growth of rice were discussed in order to control the toxicity of heavy metals and herbicides to rice. The main conclusions are as follows: 1. the effects of arsenic (0-20mg/L) and glyphosate treatment (0-20mg/L) on the seed germination of rice were studied. The results showed that arsenic and glyphosate treatment significantly inhibited the germination of rice, reduced the germination rate and seed vigor of rice seeds, root length and bud length, seed fresh weight and amylin. The inhibition of germination rate and root growth of rice seeds was greater than glyphosate, but the effect of arsenic treatment on germ growth was less than glyphosate treatment. The synergistic inhibition effect of glyphosate and arsenic compound pollution could further reduce the rate of rice germination, growth of root length and bud length and amylase activity.2.. The effects of arsenic treatment (0-5mg/L) and glyphosate treatment (0-5mg/L) on the biomass, antioxidant system, carbon metabolism and arsenic absorption of rice seedlings were studied by solution culture. The results showed that both arsenic and glyphosate significantly inhibited the growth of rice seedlings, reduced rice plant height, chlorophyll SPAD value, and fresh ground and root fresh. Heavy and root vitality. Arsenic stress reduced the antioxidant stress of rice seedlings and increased the content of MDA. However, low concentration glyphosate treatment improved the ability of antioxidant stress in rice, reduced the content of MDA, and increased the content of MDA in high concentration glyphosate treatment. There was no significant interaction between arsenic and glyphosate treatment on the content of MDA in rice. Under single treatment conditions, 1mg/LAs treatment decreased, and 5mg/LAs treatment increased the content of soluble sugar and sucrose in rice stem and leaf, while glyphosate treatment decreased the content of sugar and sugar content in rice stem and leaf except low concentration (1mg/L), and no significant activity of arsenic and glyphosate treatment on rice SPS enzyme activity. However, high concentration of arsenic and glyphosate significantly increased the activity of SS enzyme. Arsenic and glyphosate treatment had significant interaction between soluble sugar content and SPS enzyme activity, both increased soluble sugar content and reduced the activity of SPS enzyme. High concentration of glyphosate (5mg/L) reduced the content of As in rice stem and root.1mg/L. Under the condition of As and 5mg/L As treatment, the content of arsenic in rice root and stem and leaf treated with 5mg/L glyphosate were 55.1%, 89.6% (root) and 77.5%, 84.3% (upper ground).3. using soil culture method. The process, yield and mineral quality of arsenic treatment (0-80mg/L) and glyphosate treatment (0-16mg/L) single and combined treatment on rice growth period, yield and mineral quality were studied. The effects of nutrient content and the absorption and accumulation of arsenic showed that arsenic and glyphosate treatment significantly inhibited the growth of rice, reduced rice plant height and chlorophyll content, postponed the growth period of rice. Arsenic stress reduced rice yield, arsenic and glyphosate treatment had synergistic effect, resulting in further reduction in rice yield. Arsenic stress was significantly reduced. The content of N, P and K in the stems and leaves of rice plants was reduced. The content of N, P and K in the roots and stems of rice at the tillering stage was significantly interacted with the content of arsenic and glyphosate. The content of N, P and K in the roots and stems of rice at the tillering stage decreased further, but the interaction of N, P and K in the mature rice plants was not significant. The arsenic treatment was significantly improved. The content of Fe and Mn in rice stems, husks and brown rice at mature stage, but decreased the content of Cu and Zn, and glyphosate treatment significantly reduced the content of Fe and Mn in the mature rice stem, hull and brown rice, and increased the content of Zn. The arsenic and glyphosate pollution had significant interaction effects on the content of Fe, Mn, Cu and Zn in mature rice. Glyphosate promoted the absorption of arsenic in rice at tillering stage, but had no significant effect on the content of arsenic in heading and maturing stage.
【学位授予单位】：华中农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X503.231

【引证文献】