根際促生菌的促生機制研究國內(nèi)外文獻綜述目錄TOC\o"1-3"\h\u25795根際促生菌的促生機制研究國內(nèi)外文獻綜述 1314541.1產(chǎn)生植物激素 1184551.2產(chǎn)生ACC脫氨酶 2183051.3固氮 348571.4溶磷 357861.5產(chǎn)生胞外聚合物質(zhì) 4204891.6產(chǎn)生鐵載體 4131811.7提高抗氧化酶活 4促進植物生長的根際細菌（PGPR）是指位于植物的根際或根表面的可以通過多種機制改善植物生長的程度或質(zhì)量，增加植物的生長和產(chǎn)量的細菌ADDINEN.CITEADDINEN.CITE.DATA[39]，PGPR能夠通過直接或間接機制提高植物的生長和對非生物脅迫的抵抗力，因此為可持續(xù)農(nóng)業(yè)開辟了潛力和有希望的戰(zhàn)略ADDINEN.CITE<EndNote><Cite><Author>Etesami</Author><Year>2018</Year><RecNum>13</RecNum><DisplayText><styleface="superscript">[40]</style></DisplayText><record><rec-number>13</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1571129472">13</key><keyapp="ENWeb"db-id="">0</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Etesami,H.</author><author>Maheshwari,D.K.</author></authors></contributors><auth-address>DepartmentofSoilScience,UniversityCollegeofAgricultureandNaturalResources,UniversityofTehran,Tehran,Iran.Electronicaddress:hassanetesami@ut.ac.ir. DepartmentofBotanyandMicrobiology,GurukulKangriUniversity,Haridwar,Uttarakhand,India.</auth-address><titles><title>Useofplantgrowthpromotingrhizobacteria(PGPRs)withmultipleplantgrowthpromotingtraitsinstressagriculture:Actionmechanismsandfutureprospects</title><secondary-title>EcotoxicolEnvironSaf</secondary-title></titles><periodical><full-title>EcotoxicolEnvironSaf</full-title></periodical><pages>225-246</pages><volume>156</volume><edition>2018/03/20</edition><keywords><keyword>Agriculture/methods</keyword><keyword>Crops,Agricultural/*microbiology</keyword><keyword>Metals,Heavy/toxicity</keyword><keyword>*PlantDevelopment</keyword><keyword>*Rhizosphere</keyword><keyword>*Stress,Physiological</keyword><keyword>Actionmechanisms</keyword><keyword>PGPRs</keyword><keyword>Plant-microbeinteractions</keyword><keyword>Sustainableagriculture</keyword><keyword>abioticstresses</keyword></keywords><dates><year>2018</year><pub-dates><date>Jul30</date></pub-dates></dates><isbn>1090-2414(Electronic) 0147-6513(Linking)</isbn><accession-num>29554608</accession-num><urls><related-urls><url>/pubmed/29554608</url></related-urls></urls><electronic-resource-num>10.1016/j.ecoenv.2018.03.013</electronic-resource-num></record></Cite></EndNote>[40]。圖1-2根際促生菌的促生機制Figure1-2DifferentmechanismsofPGPR1.1產(chǎn)生植物激素植物激素，如脫落酸，植物生長素，赤霉素和細胞分裂素等，可通過促進生長發(fā)育和養(yǎng)分的吸收來幫助植物生長。然而，非生物脅迫對植物生長的抑制作用之一是由于這些植物激素的內(nèi)源性水平降低ADDINEN.CITE<EndNote><Cite><Author>Bari</Author><Year>2009</Year><RecNum>199</RecNum><DisplayText><styleface="superscript">[41]</style></DisplayText><record><rec-number>199</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1607318301">199</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Bari,Rajendra</author><author>Jones,JonathanD.G.</author></authors></contributors><titles><title>Roleofplanthormonesinplantdefenceresponses</title><secondary-title>PlantMolecularBiology</secondary-title></titles><periodical><full-title>PlantMolecularBiology</full-title></periodical><pages>473-488</pages><volume>69</volume><number>4</number><dates><year>2009</year><pub-dates><date>Mar</date></pub-dates></dates><isbn>0167-4412</isbn><accession-num>WOS:000263424200012</accession-num><urls><related-urls><url><GotoISI>://WOS:000263424200012</url><url>/content/pdf/10.1007/s11103-008-9435-0.pdf</url></related-urls></urls><electronic-resource-num>10.1007/s11103-008-9435-0</electronic-resource-num></record></Cite></EndNote>[41]，進而對植株生長產(chǎn)生抑制。而某些PGPR可以通過合成和分泌植物激素來平衡植物激素水平，并在脅迫條件下增加植物的生長。一些細菌可以通過合成和分泌植物激素來平衡植物激素的水平，從而在脅迫條件下增加植物的生長。在植物生長促進性狀中，IAA合成被認為是刺激植物生長的最重要機制之一，IAA致力于通過加強各種細胞防御系統(tǒng)的協(xié)調(diào)來增強針對外部不利條件的保護水平ADDINEN.CITEADDINEN.CITE.DATA[42]。據(jù)報道，有80％的根際細菌產(chǎn)生這種植物色素的能力，這些細菌通過不同的途徑從L-色氨酸產(chǎn)生IAAADDINEN.CITEADDINEN.CITE.DATA[43]。產(chǎn)生IAA的PGPR增加了植物獲取養(yǎng)分和水分的機會（提高了水的利用效率），并通過改變RSA的預(yù)期值（例如，增加了根尖的數(shù)量和根部表面積）來提高植物吸收養(yǎng)分和水分的能力（例如，增加根尖的數(shù)量和根表面積）來抵抗環(huán)境脅迫ADDINEN.CITE<EndNote><Cite><Author>Marulanda</Author><Year>2009</Year><RecNum>202</RecNum><DisplayText><styleface="superscript">[44]</style></DisplayText><record><rec-number>202</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1607319315">202</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Marulanda,Adriana</author><author>Barea,Jose-Miguel</author><author>Azcon,Rosario</author></authors></contributors><titles><title>StimulationofPlantGrowthandDroughtTolerancebyNativeMicroorganisms(AMFungiandBacteria)fromDryEnvironments:MechanismsRelatedtoBacterialEffectiveness</title><secondary-title>JournalofPlantGrowthRegulation</secondary-title></titles><periodical><full-title>JournalofPlantGrowthRegulation</full-title></periodical><pages>115-124</pages><volume>28</volume><number>2</number><dates><year>2009</year><pub-dates><date>Jun</date></pub-dates></dates><isbn>0721-7595</isbn><accession-num>WOS:000266664400003</accession-num><urls><related-urls><url><GotoISI>://WOS:000266664400003</url></related-urls></urls><electronic-resource-num>10.1007/s00344-009-9079-6</electronic-resource-num></record></Cite></EndNote>[44]。研究表明，PGPR能產(chǎn)生并分泌植物促進生長激素吲哚-3-乙酸（IAA），接種PGPR會誘導(dǎo)生長刺激作用ADDINEN.CITE<EndNote><Cite><Author>Zerrouk</Author><Year>2019</Year><RecNum>41</RecNum><DisplayText><styleface="superscript">[45]</style></DisplayText><record><rec-number>41</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1571212821">41</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Zerrouk,I.Z.</author><author>Rahmoune,B.</author><author>Khelifi,L.</author><author>Mounir,K.</author><author>Baluska,F.</author><author>Ludwig-Muller,J.</author></authors></contributors><titles><title>AlgerianSaharaPGPRconfersmaizeroottolerancetosaltandaluminumtoxicityviaACCdeaminaseandIAA</title><secondary-title>ActaPhysiologiaePlantarum</secondary-title></titles><periodical><full-title>ActaPhysiologiaePlantarum</full-title></periodical><volume>41</volume><number>6</number><dates><year>2019</year><pub-dates><date>Jun</date></pub-dates></dates><isbn>0137-5881</isbn><accession-num>WOS:000467529300001</accession-num><urls><related-urls><url><GotoISI>://WOS:000467529300001</url><url>/content/pdf/10.1007%2Fs11738-019-2881-2.pdf</url></related-urls></urls><custom7>91</custom7><electronic-resource-num>10.1007/s11738-019-2881-2</electronic-resource-num></record></Cite></EndNote>[45]，在接種菌株之后，植株所有生長參數(shù)都有改善，特別是根部鮮重和干重（分別增加了114％和121％），根的長度增加了70％以上，側(cè)根的數(shù)量增加了270％，光合作用相關(guān)參數(shù)的增加也表明了對植物的促進作用性能。BiancoADDINEN.CITEADDINEN.CITE.DATA[42]等人比較了接種促生菌的野生型苜蓿非生物脅迫抗性，接種菌株具有合成吲哚-3-乙酸（IAA）的途徑并均有表達。結(jié)果顯示，促生菌生產(chǎn)的IAA作為其內(nèi)源滲透壓物積累了更高水平的海藻糖，并顯示出對多種脅迫條件（溫度、pH、鹽度和紫外照射等）的耐受性增強，紫花苜蓿植物顯示出植物激素的重新調(diào)節(jié)，并發(fā)現(xiàn)其抗氧化活性的增強，這些結(jié)果與這些植物的衰老癥狀減輕，枝干重量增加呈正相關(guān)。1.2產(chǎn)生ACC脫氨酶乙烯是植物生長發(fā)育的必需激素之一，在植物中生長和發(fā)育的重要調(diào)節(jié)劑。但是乙烯也是植物對各種脅迫的反應(yīng)的關(guān)鍵特征。在脅迫條件下會導(dǎo)致過量乙烯的產(chǎn)生，影響植物組織例如根、莖、葉、花和果實，以及植物發(fā)育的所有階段，從而導(dǎo)致植物生長的問題ADDINEN.CITEADDINEN.CITE.DATA[46]。由于“脅迫乙烯”的產(chǎn)生顯著影響了處于脅迫條件下的植物的生長和生物量ADDINEN.CITE<EndNote><Cite><Author>Zafar-ul-Hye</Author><Year>2019</Year><RecNum>43</RecNum><DisplayText><styleface="superscript">[47]</style></DisplayText><record><rec-number>43</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1571213559">43</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Zafar-ul-Hye,M.</author><author>Danish,S.</author><author>Abbas,M.</author><author>Ahmad,M.</author><author>Munir,T.M.</author></authors></contributors><titles><title>ACCDeaminaseProducingPGPRBacillusamyloliquefaciensandAgrobacteriumfabrumalongwithBiocharImproveWheatProductivityunderDroughtStress</title><secondary-title>Agronomy-Basel</secondary-title></titles><periodical><full-title>Agronomy-Basel</full-title></periodical><volume>9</volume><number>7</number><dates><year>2019</year><pub-dates><date>Jul</date></pub-dates></dates><isbn>2073-4395</isbn><accession-num>WOS:000478660500058</accession-num><urls><related-urls><url><GotoISI>://WOS:000478660500058</url><url>/d_attachment/agronomy/agronomy-09-00343/article_deploy/agronomy-09-00343.pdf</url></related-urls></urls><custom7>343</custom7><electronic-resource-num>10.3390/agronomy9070343</electronic-resource-num></record></Cite></EndNote>[47]。1-氨基環(huán)丙烷1-羧酸鹽（ACC）是乙烯前體，能產(chǎn)生ACC脫氨酶的PGPR能夠?qū)CC裂解為氨和α-丁酮酸。也就是說，產(chǎn)生ACC脫氨酶的PGPR通過分解植物中的ACC，從而降低植物中的乙烯含量ADDINEN.CITE<EndNote><Cite><Author>Glick</Author><Year>2007</Year><RecNum>198</RecNum><DisplayText><styleface="superscript">[48]</style></DisplayText><record><rec-number>198</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1607312620">198</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Glick,BernardR.</author><author>Cheng,Zhenyu</author><author>Czarny,Jennifer</author><author>Duan,Jin</author></authors></contributors><titles><title>PromotionofplantgrowthbyACCdeaminase-producingsoilbacteria</title><secondary-title>EuropeanJournalofPlantPathology</secondary-title></titles><periodical><full-title>EuropeanJournalofPlantPathology</full-title></periodical><pages>329-339</pages><volume>119</volume><number>3</number><dates><year>2007</year><pub-dates><date>Nov</date></pub-dates></dates><isbn>0929-1873</isbn><accession-num>WOS:000250205500008</accession-num><urls><related-urls><url><GotoISI>://WOS:000250205500008</url></related-urls></urls><electronic-resource-num>10.1007/s10658-007-9162-4</electronic-resource-num></record></Cite></EndNote>[48]。因此，能夠產(chǎn)生ACC脫氨酶的促生菌通過在脅迫條件下降低乙烯，從而使根系增加，導(dǎo)致植物從土壤深處獲得更多的水和養(yǎng)分，減少部分乙烯對植物生長的抑制作用，從而促進植物在脅迫條件下的生長ADDINEN.CITE<EndNote><Cite><Author>Lim</Author><Year>2013</Year><RecNum>197</RecNum><DisplayText><styleface="superscript">[49]</style></DisplayText><record><rec-number>197</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1607311732">197</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Lim,Jong-Hui</author><author>Kim,Sang-Dal</author></authors></contributors><titles><title>InductionofDroughtStressResistancebyMulti-FunctionalPGPRBacilluslicheniformisK11inPepper</title><secondary-title>PlantPathologyJournal</secondary-title></titles><periodical><full-title>PlantPathologyJournal</full-title></periodical><pages>201-208</pages><volume>29</volume><number>2</number><dates><year>2013</year><pub-dates><date>Jun</date></pub-dates></dates><isbn>1598-2254</isbn><accession-num>WOS:000319955900010</accession-num><urls><related-urls><url><GotoISI>://WOS:000319955900010</url></related-urls></urls><electronic-resource-num>10.5423/ppj.Si.02.2013.0021</electronic-resource-num></record></Cite></EndNote>[49]。Gupta等人ADDINEN.CITE<EndNote><Cite><Author>Gupta</Author><Year>2019</Year><RecNum>51</RecNum><DisplayText><styleface="superscript">[50]</style></DisplayText><record><rec-number>51</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1572235479">51</key><keyapp="ENWeb"db-id="">0</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Gupta,S.</author><author>Pandey,S.</author></authors></contributors><auth-address>AmityInstituteofOrganicAgriculture,AmityUniversity,Noida,India.</auth-address><titles><title>ACCDeaminaseProducingBacteriaWithMultifariousPlantGrowthPromotingTraitsAlleviatesSalinityStressinFrenchBean(Phaseolusvulgaris)Plants</title><secondary-title>FrontMicrobiol</secondary-title></titles><periodical><full-title>FrontMicrobiol</full-title></periodical><pages>1506</pages><volume>10</volume><edition>2019/07/25</edition><keywords><keyword>ACCdeaminase</keyword><keyword>Pgpr</keyword><keyword>indoleaceticacid</keyword><keyword>salinitystress</keyword><keyword>siderophore</keyword></keywords><dates><year>2019</year></dates><isbn>1664-302X(Print) 1664-302X(Linking)</isbn><accession-num>31338077</accession-num><urls><related-urls><url>/pubmed/31338077</url></related-urls></urls><custom2>PMC6629829</custom2><electronic-resource-num>10.3389/fmicb.2019.01506</electronic-resource-num></record></Cite></EndNote>[50]從大蒜根際中分離出根際細菌菌株，并篩選出兩柱具有ACC脫氨酶活性的菌株，并通過盆栽試驗評估其對菜豆幼苗的生長促進潛力，結(jié)果表明，該菌株顯著抑制了受到脅迫刺激而產(chǎn)生的乙烯水平（60%），減輕了脅迫下乙烯對菌株的負面影響，增加了根長（110％），根鮮重（45％），枝長（60％），枝鮮重（255％），根生物量（220％），鹽漬脅迫下的菜豆幼苗的生物量（425％）和總?cè)~綠素含量（57％）。Sarkar等ADDINEN.CITEADDINEN.CITE.DATA[51]分離出產(chǎn)ACC脫氨酶的菌株，并優(yōu)化了ACC脫氨酶活性的不同條件，通過酶測定和FTIR進行了確認，然后，將菌株用于在鹽脅迫下使用水稻幼苗，結(jié)果發(fā)現(xiàn)，與未接種菌株的幼苗相比，經(jīng)菌株處理的幼苗在各種形態(tài)和生化特性，清除ROS的抗氧化酶活性以及減少的脅迫乙烯量方面均表現(xiàn)出改善。1.3固氮植物需要從土壤中獲得重要的常量營養(yǎng)素，PGPR能夠為植物提供額外的營養(yǎng)素或促進現(xiàn)有營養(yǎng)素的獲取，氮就是其中之一。氮植物發(fā)育中必不可少的元素，也是自然和農(nóng)業(yè)生態(tài)系統(tǒng)中有限的養(yǎng)分。一些細菌能夠固定N2，將大氣中的氮轉(zhuǎn)化為銨從而向植物提供可利用的氮元素，例如固氮菌屬ADDINEN.CITE<EndNote><Cite><Author>Kraepiel</Author><Year>2009</Year><RecNum>206</RecNum><DisplayText><styleface="superscript">[52]</style></DisplayText><record><rec-number>206</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1607323365">206</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Kraepiel,A.M.L.</author><author>Bellenger,J.P.</author><author>Wichard,T.</author><author>Morel,F.M.M.</author></authors></contributors><titles><title>Multiplerolesofsiderophoresinfree-livingnitrogen-fixingbacteria</title><secondary-title>Biometals</secondary-title></titles><periodical><full-title>Biometals</full-title></periodical><pages>573-581</pages><volume>22</volume><number>4</number><dates><year>2009</year><pub-dates><date>Aug</date></pub-dates></dates><isbn>0966-0844</isbn><accession-num>WOS:000267778600003</accession-num><urls><related-urls><url><GotoISI>://WOS:000267778600003</url><url>/content/pdf/10.1007/s10534-009-9222-7.pdf</url></related-urls></urls><electronic-resource-num>10.1007/s10534-009-9222-7</electronic-resource-num></record></Cite></EndNote>[52]，固氮螺菌屬ADDINEN.CITE<EndNote><Cite><Author>Steenhoudt</Author><Year>2000</Year><RecNum>207</RecNum><DisplayText><styleface="superscript">[53]</style></DisplayText><record><rec-number>207</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1607323676">207</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Steenhoudt,O.</author><author>Vanderleyden,J.</author></authors></contributors><titles><title>Azospirillum,afree-livingnitrogen-fixingbacteriumcloselyassociatedwithgrasses:genetic,biochemicalandecologicalaspects</title><secondary-title>FemsMicrobiologyReviews</secondary-title></titles><periodical><full-title>FemsMicrobiologyReviews</full-title></periodical><pages>487-506</pages><volume>24</volume><number>4</number><dates><year>2000</year><pub-dates><date>Oct</date></pub-dates></dates><isbn>0168-6445</isbn><accession-num>WOS:000089288700009</accession-num><urls><related-urls><url><GotoISI>://WOS:000089288700009</url></related-urls></urls><electronic-resource-num>10.1111/j.1574-6976.2000.tb00552.x</electronic-resource-num></record></Cite></EndNote>[53]等。PGPR可以通過共生和非共生氮固定，將土壤中有機態(tài)氮的礦化從而增加植物對氮的吸收ADDINEN.CITEADDINEN.CITE.DATA[54,55]。在固氮細菌中，有些是自由活動的，即不需要宿主來執(zhí)行該過程，而另一些則是共生的，僅與某些植物結(jié)合在一起才能固氮，例如豆科植物根瘤菌ADDINEN.CITE<EndNote><Cite><Author>Olanrewaju</Author><Year>2017</Year><RecNum>208</RecNum><DisplayText><styleface="superscript">[56]</style></DisplayText><record><rec-number>208</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1607324299">208</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Olanrewaju,OluwaseyiSamuel</author><author>Glick,BernardR.</author><author>Babalola,OlubukolaOluranti</author></authors></contributors><titles><title>Mechanismsofactionofplantgrowthpromotingbacteria</title><secondary-title>WorldJournalofMicrobiology&Biotechnology</secondary-title></titles><periodical><full-title>WorldJournalofMicrobiology&Biotechnology</full-title><abbr-1>WorldJ.Microbiol.Biotechnol.</abbr-1></periodical><volume>33</volume><number>11</number><dates><year>2017</year><pub-dates><date>Nov</date></pub-dates></dates><isbn>0959-3993</isbn><accession-num>WOS:000413705900004</accession-num><urls><related-urls><url><GotoISI>://WOS:000413705900004</url></related-urls></urls><custom7>197</custom7><electronic-resource-num>10.1007/s11274-017-2364-9</electronic-resource-num></record></Cite></EndNote>[56]。根瘤菌被植物細胞膜的一部分包裹起來，形成共生體，從而通過酶氮酶將大氣中的氮轉(zhuǎn)化為氨，作為回報，植物提供有機酸（用于類細菌產(chǎn)生能量），并為固氮酶的作用提供適當?shù)奈h(huán)境，從而建立了植物與細菌之間的共生關(guān)系A(chǔ)DDINEN.CITE<EndNote><Cite><Author>Olanrewaju</Author><Year>2017</Year><RecNum>208</RecNum><DisplayText><styleface="superscript">[56]</style></DisplayText><record><rec-number>208</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1607324299">208</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Olanrewaju,OluwaseyiSamuel</author><author>Glick,BernardR.</author><author>Babalola,OlubukolaOluranti</author></authors></contributors><titles><title>Mechanismsofactionofplantgrowthpromotingbacteria</title><secondary-title>WorldJournalofMicrobiology&Biotechnology</secondary-title></titles><periodical><full-title>WorldJournalofMicrobiology&Biotechnology</full-title><abbr-1>WorldJ.Microbiol.Biotechnol.</abbr-1></periodical><volume>33</volume><number>11</number><dates><year>2017</year><pub-dates><date>Nov</date></pub-dates></dates><isbn>0959-3993</isbn><accession-num>WOS:000413705900004</accession-num><urls><related-urls><url><GotoISI>://WOS:000413705900004</url></related-urls></urls><custom7>197</custom7><electronic-resource-num>10.1007/s11274-017-2364-9</electronic-resource-num></record></Cite></EndNote>[56]。FangADDINEN.CITE<EndNote><Cite><Author>Fang</Author><Year>2019</Year><RecNum>37</RecNum><DisplayText><styleface="superscript">[57]</style></DisplayText><record><rec-number>37</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1571144888">37</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Fang,Kai</author><author>Bao,Zhu-Shou-Neng</author><author>Chen,Lin</author><author>Zhou,Jie</author><author>Yang,Zhi-Ping</author><author>Dong,Xing-Fan</author><author>Zhang,Han-Bo</author></authors></contributors><titles><title>Growth-promotingcharacteristicsofpotentialnitrogen-fixingbacteriaintherootofaninvasiveplantAgeratinaadenophora</title><secondary-title>Peerj</secondary-title></titles><periodical><full-title>Peerj</full-title></periodical><volume>7</volume><dates><year>2019</year><pub-dates><date>Jun12</date></pub-dates></dates><isbn>2167-8359</isbn><accession-num>WOS:000471213700013</accession-num><urls><related-urls><url><GotoISI>://WOS:000471213700013</url><url>/articles/7099.pdf</url></related-urls></urls><custom7>e7099</custom7><electronic-resource-num>10.7717/peerj.7099</electronic-resource-num></record></Cite></EndNote>[57]從中國西南部入侵植物紫莖澤蘭的根中分離并純化了131株潛在的固氮細菌，進一步從中隨機選擇了六株分離株進行接種實驗，試驗結(jié)果表明，所有分離株對紫莖澤蘭幼苗均表現(xiàn)出顯著的正促生長作用，有趣的是，這些分離株對根生物量的促進效果高于芽生物量。1.4溶磷除了氮元素之外，最常限制植物生長的必需礦物質(zhì)元素就是磷，磷通常以一價（H2PO4-）或二價（HPO42-）可溶性形式吸收。但土壤中的大多數(shù)磷通常以不可溶的形式存在，因此盡管無機和有機磷形式豐富，但在生物學上是植物無法利用的ADDINEN.CITE<EndNote><Cite><Author>Richardson</Author><Year>2011</Year><RecNum>209</RecNum><DisplayText><styleface="superscript">[58]</style></DisplayText><record><rec-number>209</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1607326708">209</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Richardson,AlanE.</author><author>Simpson,RichardJ.</author></authors></contributors><titles><title>SoilMicroorganismsMediatingPhosphorusAvailability</title><secondary-title>PlantPhysiology</secondary-title></titles><periodical><full-title>Plantphysiology</full-title></periodical><pages>989-996</pages><volume>156</volume><number>3</number><dates><year>2011</year><pub-dates><date>Jul</date></pub-dates></dates><isbn>0032-0889</isbn><accession-num>WOS:000292294100002</accession-num><urls><related-urls><url><GotoISI>://WOS:000292294100002</url></related-urls></urls><electronic-resource-num>10.1104/pp.111.175448</electronic-resource-num></record></Cite></EndNote>[58]。某些PGPR可以溶解無機磷酸鹽，從而幫助植物應(yīng)對其磷需求ADDINEN.CITEADDINEN.CITE.DATA[55]。在植物菌根結(jié)合中，細菌在植物根部定居，并從根分泌物中獲得有機分子，并從土壤中獲得磷酸鹽。PGPR在土壤磷循環(huán)的所有三個主要成分中都起著重要作用ADDINEN.CITE<EndNote><Cite><Author>Sharma</Author><Year>2013</Year><RecNum>210</RecNum><DisplayText><styleface="superscript">[59]</style></DisplayText><record><rec-number>210</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1607327496">210</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Sharma,SeemaB.</author><author>Sayyed,RiyazZ.</author><author>Trivedi,MrugeshH.</author><author>Gobi,ThivakaranA.</author></authors></contributors><titles><title>Phosphatesolubilizingmicrobes:sustainableapproachformanagingphosphorusdeficiencyinagriculturalsoils</title><secondary-title>Springerplus</secondary-title></titles><periodical><full-title>Springerplus</full-title></periodical><volume>2</volume><dates><year>2013</year><pub-dates><date>2013</date></pub-dates></dates><isbn>2193-1801</isbn><accession-num>WOS:000209465100159</accession-num><urls><related-urls><url><GotoISI>://WOS:000209465100159</url></related-urls></urls><custom7>587</custom7><electronic-resource-num>10.1186/2193-1801-2-587</electronic-resource-num></record></Cite></EndNote>[59]。通常，PGPR可以通過酸化，螯合，交換反應(yīng)，釋放絡(luò)合或礦物溶解性化合物，有機酸和無機酸，并通過分泌多種不同的細胞外磷酸酶，催化磷酸酯的水解來使有機磷酸鹽礦化ADDINEN.CITEADDINEN.CITE.DATA[58-60]。有研究發(fā)現(xiàn)，補充微生物菌株（銅綠假單胞菌和劍蘭假單胞菌）有益于植物的生長發(fā)育，并有助于植物中磷的吸收，其促使磷酸鹽吸收的機制主要是通過微生物促進有機磷的溶解和礦化的代謝活動，代謝活動涉及質(zhì)子和不同陰離子的外排，然后釋放磷酸酶，分別導(dǎo)致磷水解和礦化ADDINEN.CITE<EndNote><Cite><Author>Khanna</Author><Year>2019</Year><RecNum>65</RecNum><DisplayText><styleface="superscript">[18]</style></DisplayText><record><rec-number>65</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1572412534">65</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Khanna,K.</author><author>Jamwal,V.L.</author><author>Gandhi,S.G.</author><author>Ohri,P.</author><author>Bhardwaj,R.</author></authors></contributors><titles><title>MetalresistantPGPRloweredCduptakeandexpressionofmetaltransportergeneswithimprovedgrowthandphotosyntheticpigmentsinLycopersiconesculentumundermetaltoxicity</title><secondary-title>ScientificReports</secondary-title></titles><periodical><full-title>ScientificReports</full-title></periodical><volume>9</volume><dates><year>2019</year><pub-dates><date>Apr</date></pub-dates></dates><isbn>2045-2322</isbn><accession-num>WOS:000463984600013</accession-num><urls><related-urls><url><GotoISI>://WOS:000463984600013</url><url>/articles/s41598-019-41899-3.pdf</url></related-urls></urls><custom7>5855</custom7><electronic-resource-num>10.1038/s41598-019-41899-3</electronic-resource-num></record></Cite></EndNote>[18]。1.5產(chǎn)生胞外聚合物質(zhì)胞外聚合物主要指胞外多糖，它是由糖單元形成的長鏈多糖。這類化合物在微生物生長階段釋放，并且由于它們未附著在微生物細胞表面，因此可以從附著在細胞表面分離出來ADDINEN.CITE<EndNote><Cite><Author>Kaushal</Author><Year>2016</Year><RecNum>214</RecNum><DisplayText><styleface="superscript">[61]</style></DisplayText><record><rec-number>214</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1607350669">214</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Kaushal,Manoj</author><author>Wani,SuhasP.</author></authors></contributors><titles><title>Rhizobacterial-plantinteractions:Strategiesensuringplantgrowthpromotionunderdroughtandsalinitystress</title><secondary-title>Agriculture,Ecosystems&Environment</secondary-title></titles><periodical><full-title>Agriculture,Ecosystems&Environment</full-title></periodical><pages>68-78</pages><volume>231</volume><keywords><keyword>Drought</keyword><keyword>Aalinity</keyword><keyword>IST</keyword><keyword>Rhizobacteria</keyword><keyword>Microarray</keyword><keyword>Signalling</keyword></keywords><dates><year>2016</year><pub-dates><date>2016/09/01/</date></pub-dates></dates><isbn>0167-8809</isbn><urls><related-urls><url>/science/article/pii/S0167880916303450</url></related-urls></urls><electronic-resource-num>/10.1016/j.agee.2016.06.031</electronic-resource-num></record></Cite></EndNote>[61]。胞外多糖可幫助細菌在惡劣的環(huán)境中生存并承受環(huán)境壓力。例如，在巴西固氮螺菌中已鑒定出包含高分子量碳水化合物復(fù)合物（脂多糖-蛋白質(zhì)復(fù)合物和多糖-脂質(zhì)復(fù)合物）的莢膜材料，可在干旱條件下保護該細菌ADDINEN.CITE<EndNote><Cite><Author>Konnova</Author><Year>2001</Year><RecNum>215</RecNum><DisplayText><styleface="superscript">[62]</style></DisplayText><record><rec-number>215</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1607350737">215</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Konnova,S.A.</author><author>Brykova,O.S.</author><author>Sachkova,O.A.</author><author>Egorenkova,I.V.</author><author>Ignatov,V.V.</author></authors></contributors><titles><title>Protectiveroleofthepolysaccharide-containingcapsularcomponentsofAzospirillumbrasilense</title><secondary-title>Microbiology</secondary-title></titles><periodical><full-title>Microbiology</full-title></periodical><pages>436-440</pages><volume>70</volume><number>4</number><dates><year>2001</year></dates><work-type>Article</work-type><urls><related-urls><url>/inward/record.uri?eid=2-s2.0-8644291691&doi=10.1023%2fA%3a1010434227671&partnerID=40&md5=66d9ad7374884187c3241a01b68e273b</url><url>/content/pdf/10.1023/A:1010434227671.pdf</url></related-urls></urls><electronic-resource-num>10.1023/A:1010434227671</electronic-resource-num><remote-database-name>Scopus</remote-database-name></record></Cite></EndNote>[62]。據(jù)報道，PGPR在脅迫條件下（例如，水分脅迫條件下）的胞外多糖產(chǎn)量要高于非脅迫條件下的產(chǎn)量ADDINEN.CITE<EndNote><Cite><Author>Naseem</Author><Year>2014</Year><RecNum>216</RecNum><DisplayText><styleface="superscript">[63]</style></DisplayText><record><rec-number>216</rec-number><foreign-keys><keyapp="EN"db-id="2s2w05etat5xs8ep0dcp2rvnswve2w0az9fz"timestamp="1607351450">216</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>Naseem,Hafsa</author><author>Bano,Asghari</author></authors></contributors><titles><title>Roleofplantgrowth-promotingrhizobacteriaandtheirexopolysaccharideindroughttoleranceofmaize</title><secondary-