香蒲耐营养盐的生理机制及其对两种水华藻类的化感作用研究

发布时间：2018-04-03 13:24

本文选题：香蒲　切入点：铜绿微囊藻　出处：《浙江农林大学》2017年硕士论文

【摘要】：水体富营养化是我国严重的环境问题,富营养化可导致蓝藻水华频繁爆发,造成大范围的水质恶化,破坏水体景观和水生态系统功能,使水产养殖业蒙受经济损失,加剧水资源的危机,威胁人类身体健康,因此,有效控制富营养化水体中的藻类,防止水华发生已成为目前世界环境领域亟需解决的问题。传统的除藻方法,包括物理、化学和生物方法,都存在明显的缺点,而水生植物化感抑藻是一种低成本、长效性、环境友好型的方法,为寻找既能耐营养盐胁迫、又能有效抑藻的水生植物,本文探讨了香蒲(Typha orientalis)对不同程度富营养盐的耐受能力和生理机制,研究了香蒲对铜绿微囊藻(Microcystis aeruginosa)和水华鱼腥藻(Anabaena flos-aquae)的抑制作用和机理,并对香蒲中的化感抑藻物质进行了分离鉴定。主要内容如下:(1)通过不同程度的富营养盐处理香蒲,研究香蒲对富营养的耐性机制,及其对水体中的氮磷去除作用,结果表明香蒲对富营养盐具有很好的耐受性,同时其又可以有效去除富营养化水体中的氮磷,氮的去除率在中富营养中达到最大,为77.33%,而磷的去除率在轻富营养中达到最大,为84.00%。在重富营养水体以下,香蒲的叶绿素含量升高,同时通过提高超氧化物歧化酶(SOD)和过氧化物酶(POD)活性来清除过多的活性氧,从而抵御营养盐的胁迫,使自身生长良好,在超富营养条件下,香蒲的叶绿素含量、SOD和POD活性与对照相比下降,丙二醛(MDA)含量大幅度升高,说明活性氧的产生超过了抗氧化酶系统的清除能力,香蒲的生长受到了严重的胁迫,因此香蒲对重富营养以下的水体修复和水华防治有着极其重要的意义。(2)通过香蒲不同部位水浸提液处理4种水生植物种子,结果表明:香蒲各部位浸提液对四种植物的发芽率、幼芽和幼根的生长均有显著的化感抑制作用,总体趋势表现出低促高抑的双重浓度效应;不同部位浸提液对4种水生植物的抑制作用强弱顺序为叶浸提液蒲黄浸提液根浸提液,且对幼根生长的影响大于幼芽;3种浸提液处理下,黄菖蒲幼苗体内MDA含量与SOD活性表现出升高后下降的趋势。香蒲水浸提液通过对水生植物的化感效应,引起细胞的膜脂过氧化加剧,抗氧化系统受损,从而抑制水生植物种子的萌发和幼苗的生长,叶片是香蒲主要的化感作用部位。(3)通过不同初始藻密度实验,发现在香蒲叶浸提液作用下,当初始密度为104 ind·L-1时,藻类的生长没有受到明显的影响,对初始藻密度为106 ind·L-1、107 ind·L-1的铜绿微囊藻具有显著的抑制作用,第10 d的抑制率分别为71.85%和59.49%,并且当初始藻密度为106 ind·L-1时,香蒲的抑藻效果最好。不同组织部位抑藻实验,发现香蒲不同部位对铜绿微囊藻的抑制作用强弱不同,表现叶浸提液根浸提液蒲黄浸提液,在第10 d时,叶浸提液、根浸提液和蒲黄浸提液对铜绿微囊藻的抑制率为别为72.35%、54.57%、30.7%,叶片是香蒲最强的抑藻部位。同时香蒲叶浸提液对铜绿微囊藻和水华鱼腥藻的化感作用表现为“低促高抑”的现象,随浸提液浓度的增加,抑制作用增强,且对铜绿微囊藻的抑制作用明显大于水华鱼腥藻,说明香蒲对两种藻类的化感作用具有一定的选择性,在质量浓度为50.00 g·L-1时,第12 d对铜绿微囊藻和水华鱼腥藻的抑制率分别为91.37%和65.64%。(4)通过对铜绿微囊藻和水华鱼腥藻叶绿素a含量、细胞膜透性、可溶性蛋白含量、抗氧化酶活性、MDA含量的变化,研究了香蒲对铜绿微囊藻及水华鱼腥藻的化感抑制机理,结果表明,实验过程中两种藻类细胞内叶绿素a含量逐渐减少,细胞膜透性逐渐增大,可溶性蛋白含量、SOD、过氧化氢酶(CAT)和POD活性、MDA含量均呈现先增加,后下降的趋势,表明香蒲叶浸提液对两种藻类细胞具有胁迫效应,造成活性氧的大量积累后,引起细胞的膜脂过氧化加剧,细胞结构严重受损,细胞膜的透性增大,抗氧化酶系统受到损伤,同时促进叶绿素a的分解,干扰细胞代谢,影响光合作用,从而强烈抑制铜绿微囊藻和水华鱼腥藻的生长。(5)香蒲中的化感抑藻物质经分离鉴定后发现,香蒲中的化感物质多为酚酸、脂肪酸、酯、酮和酰胺类等物质。通过化感物质的联合抑藻实验,结果表明邻苯二酚和苯甲酸联合方式具有明显的协同作用,而棕榈酸和苯甲酸联合方式协同作用不明显。
[Abstract]:Eutrophication is a serious environmental problem in China, eutrophication can lead to frequent outbreaks of algal blooms caused by water, large range of deterioration, destruction of water landscape and water ecosystem function, the aquaculture industry suffered economic losses, intensified water resources crisis, threats to human health. Therefore, the effective control of eutrophic water the algae bloom has become an urgent need to prevent the world environment problem. The traditional methods of removing algae, including physical, chemical and biological methods have obvious shortcomings, and the aquatic plant allelopathy of algae is a kind of low cost, long-term, environmentally friendly method, stress for both ability of nutrients, and can effectively inhibit algae in aquatic plants, this paper discusses the cattail (Typha orientalis) in different eutrophic salt tolerance and physiological mechanism of cattail of Microcystis aeruginosa (Microcys Tis aeruginosa) and Anabaena flosaquae (Anabaena flos-aquae) the inhibitory effect and mechanism of Typha in allelopathic inhibitory substances were isolated and identified. The main contents are as follows: (1) through different degree eutrophic salt treatment of cattail, Typha angustifolia on tolerance mechanism of eutrophication, and its effect on the removal of nitrogen the results show that the phosphorus in water, Typha has good tolerance for nutrient rich, at the same time, it can effectively remove nitrogen and phosphorus in eutrophic water, the nitrogen removal rate in eutrophication reaches a maximum of 77.33%, and the removal rate of phosphorus in light eutrophic reaches a maximum at 84.00%. heavy eutrophic water, chlorophyll content increased at the same time by increasing the cattail, superoxide dismutase (SOD) and peroxidase (POD) activity to remove excessive reactive oxygen species, thereby resisting nutrient stress, make themselves grow well in the super rich nutrition Under the condition, the chlorophyll content of Typha, SOD and POD activity compared with the control group decreased, malondialdehyde (MDA) content increased, indicating the generation of reactive oxygen species than the antioxidant system of scavenging ability of Typha growth suffered severe stress, so the rich cattail is extremely important nutrient water remediation and the following prevention. (2) the water extracts from different plant seeds, 4 kinds of aquatic plants and the results showed that the germination rate of liquid extraction parts of cattail of four plants, growth of shoots and roots had significant allelopathic effect, the overall trend showed low promoting effect of high concentration of double under the different parts; extracting the intensity sequence of inhibition fluid of 4 species of aquatic plants extracts of pollen Typhae extract root extract as leaf dip, and greater impact on plumule radicle growth; 3 kinds of extracts, irispseudacorus seedlings MDA The content and activity of SOD showed a downward trend after rising. Cattail extracts by aquatic plant allelopathic effect caused by membrane lipid peroxidation and antioxidant system damage, thereby inhibiting the aquatic plant seeds germination and seedling growth, leaf is mainly Typha allelopathy (3 sites.) by different initial algal density experiment, found in the cattail leaf extract effect, when the initial density of 104 ind - L-1, the growth of algae was not significantly affected, has obvious inhibitory effect on initial algal density for Microcystis aeruginosa 106 ind - ind - L-1107 L-1 D, the inhibition rate of tenth were 71.85% and 59.49%, and when the initial algal density was 106 ind - L-1, the best effect of antialgal cattail. Different parts of algicidal experiments, it was found that the inhibitory effect of different parts of cattail of Microcystis aeruginosa in different leaf extracts of root, performance Extracts of pollen Typhae extract, at tenth D, the leaf extract, root extract and pollen inhibition effect of water-soluble extracts on Microcystis aeruginosa was not 72.35%, 54.57%, 30.7%, is part of the blade. At the same time the strongest antialgal cattail Typha leaf extracts on Microcystis aeruginosa and bloom Anabaena allelopathy is low concentration and high suppression "phenomenon, with the increasing concentration of the extract, the inhibition, and the inhibition of Microcystis aeruginosa was significantly higher than that of Anabaena Flos aquae, Typha angustifolia on two species of algae allelopathy has certain selectivity in concentration 50 g L-1 twelfth D, inhibition of Microcystis aeruginosa and Anabaena rate were 91.37% and 65.64%. (4) of Microcystis aeruginosa and Anabaena flosaquae chlorophyll a content, cell membrane permeability, soluble protein content, antioxidant enzyme activity, the changes of MDA content, research the cattail the micro P. Microcystis and Anabaena allelopathic inhibition mechanism, experimental results show that in the process of two kinds of algae cell chlorophyll a content decreased, cell membrane permeability increased gradually, the content of soluble protein, SOD, catalase (CAT) and POD activity, MDA content increased first and then decreased with the increase of show, cattail leaf extract has stress effects on two kinds of algal cells, causing accumulation of ROS, caused membrane lipid peroxidation of cell increased, cell structure was severely damaged, the cell membrane permeability increased, antioxidant system damage, and promote the decomposition of chlorophyll a, disturbance of cell metabolism, photosynthesis thus, strong inhibition of Microcystis and Anabaena growth. (5) in Typha allelopathic inhibitory substances through isolation and identification showed that the Allelochemicals of Typha for phenolic acids, fatty acids, esters, ketones and amides by other substances. The algal inhibition experiment of sensory substances showed that the combination of catechol and benzoic acid had obvious synergistic effect, while the combination of palmitic acid and benzoic acid had no synergistic effect.

【学位授予单位】：浙江农林大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X52;Q945

【参考文献】