海滨木槿论文：海滨木槿和蜡杨梅对海水胁迫的光合生理响应

海滨木槿论文:海滨木槿和蜡杨梅对海水胁迫的光合生理响 应【中文摘要】本研究以杭州湾滨海湿地生态系统研究站为平台， 以海滨木槿(Hibiscus hamabo Sieb.et Zucc.)和蜡杨梅(Myrica cerifera)为研究对象，通过模拟不同程度的海水胁迫试验，连续测定 了两种植物的光合特征、生理生长及形态结构特征,旨探索两种植物 对海水胁迫的光合生理响应机理及差异,为消浪植物构建提供理论依 据。研究结果表明:两种植物在受到海水水淹胁迫后，光合特性的变化 存在一致性，随水淹时间的延长净光合速率(Pn)表现为逐渐下降的趋 势。同时发现海水胁迫主要影响海滨木槿午后光合速率的恢复，而海 水胁迫对蜡杨梅光合高峰期的影响较大。通过分析海水胁迫条件下两 种植物光合速率变化的原因，其结论如下：(1)在光合作用过程中，首 先对Pn与各个光合因子进行通径分析,结果表明海水胁迫下蒸腾速 率(Tr)、胞间CO2浓度(Ci)均是影响两种植物Pn的直接因子,因此海 水胁迫下Tr、Ci的大小直接影响植物光合特性。另外，对于海滨木槿 每天水淹时间2h、水淹深度15cm的处理和水淹时间4h、水淹深度 25cm的处理直接影响因子为Tr、PAR(光强)，水淹程度较深的水淹时 间6h、水淹深度35cm的处理和水淹时间8h、水淹深度45cm的处理 直接影响因子变为Cond(气孔导度)、Ci,对于蜡杨梅每天水淹时间 2h、水淹深度15cm的处理和水淹时间4h、水淹深度25cm的处理直 接影响因子为Tr、Cond,水淹程度较深的水淹时间6h、水淹深度35cm 的处理和水淹时间8h、水淹深度45cm的处理直接影响因子变为Ci、 VPD（蒸汽压亏缺值）。（2）在光合色素方面，海滨木槿叶绿素a/b初期 先增加后降低，后期逐渐增加的趋势，说明叶绿素b分解速度较快，即 植物在水淹后的捕光色素蛋白复合物降解快，而光系统反应中心降解 的慢,表明受到水淹影响后，植物通过调节叶片叶绿素a与叶绿素b的 比值来维持其较高的光合能力;蜡杨梅叶绿素a/b呈现先增加后下降 趋势，说明初期捕光色素蛋白复合物降解快，而后期光系统反应中心 降解的快。（3）在呼吸能耗方面，植物光合作用降低导致的大量过剩光 能可以通过光呼吸和叶绿素荧光消除。海滨木槿和蜡杨梅在中等胁迫 程度下乙醇酸氧化酶活性最大，光呼吸最大，减轻强光危害的能力也 最大，而水淹程度较深时，乙醇酸氧化酶活性显著降低,光呼吸抵御胁 迫能力降低。通过对叶绿素荧光的观测发现,由热耗散引起的非光化 学淬灭（qN或NPQ）呈现上升趋势。说明海水胁迫下过剩的光能大量的 由非光化学淬灭进行耗散。（4）在渗透调节方面,水淹环境下蜡杨梅更 能积极主动的积累可溶性糖，储蓄能量、调节渗透压以抵御胁迫环境, 但海滨木槿叶片淀粉含量在整个试验期内大体上呈现逐渐增加的趋 势,而蜡杨梅则在L4处理时就已出现淀粉含量的大幅度下降,同时蜡 杨梅可溶性蛋白含量比海滨木槿提前出现下降拐点。因此在植物渗透 调节水淹胁迫的能力方面海滨木槿要优于蜡杨梅。通过对海水胁迫下 海滨木槿和蜡杨梅形态指标的观测发现,海水胁迫程度越深水淹时间 越长叶片黄化程度越严重，植物高生长、根系生长越受到抑制。但同 时由于海水胁迫下海滨木槿不定根的生长，促进了茎皮孔的增大及植 物茎的横向生长，因此植物地径明显高于对照。另外海水胁迫下海滨 木槿还具有较强的萌蘖能力,H6处理下海滨木槿嫩枝数量明显增多， 显著高于对照和其他处理。而蜡杨梅无不定根、嫩枝数量的增长，苗 高、地径均随水淹时间的延长和水淹程度的加深逐渐下降。因此通过 形态指标的观测我们可以判断海滨木槿较蜡杨梅抗水淹能力强。【英文摘要】In order to discover the differences of response to seawater duress between Hibiscus hamabo Sieb.et Zucc.and Myrica cerifera, we devised a controlled experiment, which was based on the platform of wetland ecosystem research station that was located in gulf Hangzhou, to measure the indices of physiology, characteristics of photosynthesis and analyze the dissecting structure of leaves.The results showed that the change of photosynthetic characteristics under seawater flooding stress was the same betweent Hibiscus hamabo and Myrica cerifera. in the initial period of duress, the photosynthesize was decreased gradually as the delay of flooding time. At the same time the flooding stress mainly influence the restoration of photosynthesize for Hibiscus hamabo in the afternoon, but thestress had a strong effect on photosynthesize s peak of Myrica cerifera. The cause of photosynthesize s difference of the two kinds of plants under seawater flooding stress may concluded:(1)First, we found that the value of photosynthesize is determined by the value of T and Ci after the path anslysis of Pn and other factors. So, Ti and Ci influnence Pn directly.In additon, to Hibiscus hamabo the direct influence factors of the treatments which flooded 2 hours and 15 cm depth and flooded 4 hours and 25 cm depth are Tr and PAR. The direct influence factors of the treatments which flooded 6 hours and 35 cm depth and flooded 8 hours and 45 cm depth are Cond and Ci. To Myrica cerifera the direct influence factors of the treatments which flooded 2 hours and 15 cm depth and flooded 4 hours and 25 cm depth are Tr and Cond. The direct influence factors of the treatments which flooded 6 hours and 35 cm depth and flooded 8 hours and 45 cm depth are Ci and VPD.(2)We also found by research the content of chlorophyll a/b of Hibiscus hamabo Sieb.et Zucc increased then decreased first, afterwards increased gradually.It showed that chlorophyll b decomposed fast which meaned light harvesting complexes(LHC) decomposed fast. Hovever, photosystem reaction center decomposed slowly, which meaned plant could keep higher photosynthesis ability by adjusting the ratio of chlorophyll a and chlorophyll b.The content of chlorophyll a/b of Myrica cerifera increased then decreased, which showed LHC decomposed fast initially, then photosystem reaction center demoposed fast.(3)The more excess light energy which photosynthesis s drop caused might be eliminated by photorespiration and chlorophyll fluorescence in respiratory energy. Glycolate oxidase(GO) activity and photorespiration was the strongest of the Hibiscus hamabo Sieb.et Zucc and Myrica cerifera in the middle degree.So the ability of relieving light damage was strongest. When flooding stress was stronger, GO activity was reduced significantly and the ability of resisting stress by photorespiration.Through observing chlorophyll fluorescence, NPQ of heat dissipation caused was increased. It meaned that more excess light energy was dissipated by qp under seawater stress.(4)In osmotic adjustment wefound that Myrica cerifera could accumulate soluble sugar for storing engery active and intiative, in order to resist stress. Hovevery, the content of leafs starch of Hibiscus hamabo Sieb.et Zucc was gradually increased in the main. The content of leafs starch of Myrica cerifera was decreased greatly in L4 treatment. Meanwhile the soluble protein of Myrica cerifera was decreased earlier than that of Hibiscus hamabo Sieb.et Zucc. So Hibiscus hamabo Sieb.et Zucc was better than Myrica cerifera in the osmotic adjustment.Through the observation to the shape of Hibiscus hamabo and Myrica cerifera, the results showed that as the delay of flooding time, the degree of yellow was increased gradually and the growthof the plant and roots were subdued. The growth of adventitious roots of Hibiscus hamabo under the seawater flooding promoted the enlargement of Stem lenticel and the crossgrowth of the stem. Therefore, the ground diameter of plants in treatment groups were higher than those in control group. In addition, Hibiscus hamabo were capbale to sprout under seawater flooding and thus the number of shoot of Hibiscus hamabo in the H6 treament was obviously higher than other treatments.According to the lack of adventitious roots, the number of shoot, the height of seedling and the ground diameter were dicreased as the delay of flooding time.Therefore, by observing morphological indicators we can determine that the resistance to flooding of Hibiscus hamabo was stronger than Myrica cerifera【关键词】海滨木槿蜡杨梅海水胁迫光合生理【英文关键词】Hibiscus hamabo Sieb.et Zucc Myrica cerifera seawater stress Photosynthesis physiology【目录】海滨木槿和蜡杨梅对海水胁迫的光合生理响应摘要5-7 ABSTRACT 7-8 第一章绪论 14-231.1 引言14-201.1.1研究背景141.1.2国内外研究现状及评述14-191.1.3研究目的及意义19-201.1.4项目来源及经费支持201.2研究内容20-211.3研究技术路线21-23 第二章研究材料与方法23-332.1试验地概况232.2试验材料232.3试验处理23-252.4测定方法25-322.4.1野外测定25-262.4.2模拟试验测定26-322.5数据处理方法32-33第三章结果分析33-663.1野外环境下海滨木槿和蜡杨梅光合特征变化33- 343.2海水胁迫下海滨木槿和蜡杨梅光合特征响应34- 473.2.1海水胁迫下净光合速率变化 34-363.2.2海水胁迫下气孔导度变化36-373.2.3海水胁迫下胞间C0_2浓度变化37-383.2.4海水胁迫下蒸腾速率的变化38-393.2.5净光合速率和其他生理生态因子的回归分析和通径分析39-413.2.6海水胁迫下光响应变化41-453.2.7海水胁迫下叶绿素荧光变化45-473.3海水胁迫下海滨木槿及蜡杨梅生理指标响应47-563.3.1海水胁迫下叶绿素含量变化47-503.3.2海水胁迫下可溶性糖含量变化50-513.3.3海水胁迫下淀粉含量变化51- 523.3.4海水胁迫下可溶性蛋白含量变化52- 543.3.5海水胁迫下根系活力变化54-553.3.6海水胁迫下乙醇酸氧化酶活性变化55-563.4海滨木槿及蜡杨梅生长及形态指标变化56-613.4.1海水胁迫下外观形态变化56-573.4.2海水胁迫下苗高、地径变化57-583.4.3海水胁迫下生物量变化 58-593.4.4海水胁迫下根形态变化59-603.4.5海滨木槿和蜡杨梅生长、生理指标综合评价60-613.5海水胁迫下叶片解剖结构变化61-66 第四章 结论与讨论66-714.1结论与讨论66-694.1.1野外环境下光合特性响应 664.1.2海水胁迫下光合特性响应66-674.1.3海水胁迫下光合作用过程对光合作用的调控67-684.1.4海水胁迫下呼吸能耗对光合作用的调控684.1.5海水胁迫下渗透调节物质对光合作用的调控68-694.1.6海水胁迫下生长形态响应694.2展望69-71参考文献71-78在读期间的学术研究78-79 致谢 79-80 详细摘要80-82I【曲采买全文魁】1.399388.48 1381.13.72.1同时提供论文写作一对一辅导和论文发表服务保过包发一t说明】本文仅为中国学术文献总库合作提供，无浮版极。作者如有异该请与总库或学校联秀