發(fā)布時(shí)間：2018-03-09 22:11

  本文選題：超積累植物　切入點(diǎn)：鋅　出處：《浙江大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：超積累生態(tài)型東南景天(Sedum alfredii Hance)是我國(guó)原生的鋅(Zn)/鎘(Cd)超積累植物,對(duì)重金屬污染土壤具有較好的修復(fù)潛力,但其生物量較小,修復(fù)效率亟需進(jìn)一步提高。近年來(lái),利用植物促生菌提高植物修復(fù)效率已成為國(guó)內(nèi)外研究的熱點(diǎn)。本研究以東南景天及其莖中分離的特異內(nèi)生菌熒光假單胞桿菌Sasm05為材料,通過(guò)溶液培養(yǎng)試驗(yàn),采用三親結(jié)合法、激光共聚焦顯微鏡分析、電感耦合等離子體質(zhì)譜分析(ICP-MS)、實(shí)時(shí)定量PCR(q-RT-PCR)等技術(shù)研究了強(qiáng)化接種Sasm05對(duì)東南景天鋅吸收與轉(zhuǎn)運(yùn)的影響及其生理機(jī)制,取得的主要研究成果如下:1、通過(guò)三親結(jié)合法對(duì)Sasm05進(jìn)行了綠色熒光蛋白(GFP)標(biāo)記,利用激光共聚焦顯微鏡觀察發(fā)現(xiàn)強(qiáng)化接種的Sasm05進(jìn)入到了植物的根表、根內(nèi)和莖中。隨著Zn處理濃度的增加,東南景天地上部與根系的生物量與Zn濃度均顯著增加。接種Sasm05后,地上部生物量比未接種對(duì)照增加了 37.3%-59.2%,根系生物量增加了 58%-108%;地上部的Zn濃度增加了 16.7%-54.7%,根系的Zn濃度增加了 37%-40.6%;葉綠素含量增加了 35.5%-56.2%。同時(shí),Sasm05顯著增加了 HMA、Nramp和ZIP等轉(zhuǎn)運(yùn)蛋白基因的表達(dá)量。2、研究了強(qiáng)化接種Sasm05對(duì)東南景天鋅吸收轉(zhuǎn)運(yùn)動(dòng)力學(xué)的影響,發(fā)現(xiàn)隨著培養(yǎng)時(shí)間的增加,植物生物量顯著增加;在200 μMZn處理濃度下,30 d時(shí)地上部和根系的生物量增幅最大,分別為262%和421%;接種Sasm05進(jìn)一步提高了地上部和根系的生物量,增幅為34.5%和46.8%。相比未接種對(duì)照,Sasm05提高了植物體內(nèi)的Zn濃度(9.2%-120%),葉綠素含量(15.3%-69.8%)以及金屬離子轉(zhuǎn)運(yùn)蛋白基因的表達(dá)量,其中根系Nramp1的表達(dá)量增加了 2.5-34.2 倍。3、比較了強(qiáng)化接種Sasm05和IAA處理對(duì)東南景天根系發(fā)育和鋅吸收轉(zhuǎn)運(yùn)的作用效應(yīng)。發(fā)現(xiàn)IAA對(duì)根系生物量的影響主要表現(xiàn)為低濃度促進(jìn),高濃度抑制,確定促生效應(yīng)最佳的IAA濃度為11μM。Sasm05和IAA均可提高地上部鋅的積累量,其中Sasm05顯著增加了植物地上部的生物量,其促生效應(yīng)比IAA更強(qiáng);并且可促進(jìn)Zn、Ca、Fe、Mg、Mn、Cu等金屬離子在植物植物地上部和根系的濃度,而IAA作用效果不明顯。進(jìn)一步分析發(fā)現(xiàn),Sasm05與IAA均影響Nramp1和IRT1等轉(zhuǎn)運(yùn)基因的表達(dá),但兩者的作用效應(yīng)并不一致,說(shuō)明Sasm05不僅可能通過(guò)分泌IAA發(fā)揮促生作用,還可能直接影響相關(guān)基因的表達(dá)進(jìn)而調(diào)節(jié)重金屬的吸收運(yùn)輸,從而調(diào)控植物體內(nèi)的重金屬濃度以達(dá)到提高東南景天鋅富集的效應(yīng)。
[Abstract]:The superaccumulative ecotype Sedum alfredii Hanceis a native zinc-zn-zn / CD / CD superaccumulant plant in China, which has good remediation potential for heavy metal contaminated soils, but its biomass is small, and its remediation efficiency needs to be further improved in recent years. It has become a hot topic to improve the efficiency of phytoremediation by plant growth promoting bacteria. In this study, Sasm05, a specific endophytic bacterium isolated from Sedum and its stems, was used as the material, and the method of three-amphiphilic combination was used in the solution culture experiment. Laser confocal microscopy (LCM), inductively coupled plasma mass spectrometry (ICP-MS) and real-time quantitative PCRQ- RT-PCR were used to study the effects of enhanced inoculation of Sasm05 on zinc absorption and transport and its physiological mechanism. The main research results were as follows: 1. Sasm05 was labeled with green fluorescent protein (GFP) by the three-amphiphilic binding method. Using confocal laser microscopy, it was found that the Sasm05 inoculated with enhanced inoculation entered the root surface of the plant. With the increase of Zn concentration, the biomass and Zn concentration of shoot and root increased significantly. After inoculation with Sasm05, the biomass and Zn concentration of shoot and root increased significantly. The aboveground biomass increased by 37.3-59.2 and the root biomass increased by 58-108. the Zn concentration in the shoot increased 16.7-54.7, the root Zn concentration increased 37-40.6. the chlorophyll content increased 35.5-56.2.The Sasm05 significantly increased the HMANramp. And the expression of ZIP and other transporter genes. 2. The effect of Sasm05 inoculation on zinc uptake and transport kinetics was studied. The results showed that the biomass of plant increased significantly with the increase of culture time, and the biomass of shoot and root increased most at the concentration of 200 渭 MZn for 30 days, which were 262% and 421, respectively, and inoculated with Sasm05 further increased the biomass of shoot and root. The increases were 34.5% and 46.8. Compared with the uninoculated control, Sasm05 increased the Zn concentration in the plant and the content of chlorophyll in the plant, the chlorophyll content was 15.3- 69.8%) and the expression of the metal ion transporter gene. The expression of Nramp1 in roots increased by 2.5-34.2 times. The effects of Sasm05 and IAA on root development and zinc uptake and transport were compared. It was found that the effect of IAA on root biomass was mainly promoted by low concentration. The best concentration of IAA, 11 渭 M. Sasm05 and IAA, could increase the accumulation of Zn in shoot, and Sasm05 significantly increased the biomass of shoot, which should be stronger than IAA. In addition, the concentration of metal ions such as IAA in plant shoots and roots was promoted, but the effect of IAA was not obvious. It was found that both Sasm05 and IAA affected the expression of Nramp1 and IRT1 genes, but the effects were not consistent. It is suggested that Sasm05 may not only promote growth by secreting IAA, but also directly affect the expression of related genes and regulate the absorption and transport of heavy metals, thus regulating the concentration of heavy metals in plants so as to increase the concentration of zinc in Sedum southeastern China.
【學(xué)位授予單位】：浙江大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：X17;X53

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1 羅莎;Sasm05菌株提高東南景天鋅富集的作用機(jī)制研究[D];浙江大學(xué);2017年

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本文編號(hào)：1590483