根瘤菌

根瘤菌主要指與豆類作物根部共生形成根瘤並能固氮的細菌，一般指根瘤菌屬和慢生根瘤菌屬；兩屬都屬於根瘤菌目。

根瘤菌屬
瓊脂平皿上的熱帶根瘤箘。
科學分類
域：	細菌域 Bacteria
門：	假單胞菌門 Pseudomonadota
綱：	α-變形菌綱 Alphaproteobacteria
目：	根瘤菌目 Rhizobiales
科：	根瘤菌科 Rhizobiaceae
屬：	根瘤菌屬 Rhizobium Frank, 1889
模式種
Rhizobium leguminosarum (Frank, 1879) Frank, 1889
Species
See text.

大豆的根瘤，每一個都含有數十億根瘤菌（Bradyrhizobium）。

根瘤菌侵入寄主根內，刺激根部皮層和中柱鞘的某些細胞，引起這些細胞的強烈生長，使根的局部膨大形成根瘤；根瘤菌在根內定居，植物供給根瘤菌以礦物養料和能源，根瘤菌固定大氣中游離氮氣，為植物提供氮素養料，兩者在拮抗寄生關係中處於均衡狀態而表現共生現象。

根瘤菌細胞呈杆狀，有鞭毛和莢膜，鞭毛為正常的活動器官，無芽孢，革蘭氏染色陰性，屬需氧型。在根瘤中生活的菌體形式多種多樣，有梨形、棍棒型或T、X、Y等型，這種變形的菌體成為類菌體；類菌體在豆科植物體內不生長繁殖，卻能與豆科植物共同固氮，對豆科植物有良好作用。

每種根瘤菌只能與一種或幾種植物建立共生關係，如下表：

根瘤菌種類	對應共生植物
苜蓿根瘤菌	苜蓿、草木樨
三葉草根瘤菌	三葉草
豌豆根瘤菌	豌豆、蠶豆
菜豆根瘤菌	菜豆
紫雲英根瘤菌	紫雲英
大豆根瘤菌	大豆
豇豆根瘤菌	豇豆、花生、綠豆、赤豆、檉麻、扁豆、刀豆等

此外，還有些微生物能同非豆類植物共同形成根瘤固氮，主要是一些放線菌（如：小頭木麻黃、赤楊、楊梅）、藍綠菌（如：蘇鐵、竹柏、滿江紅）。

下屬物種

根瘤菌屬 包括以下物種：

• Rhizobium acaciae Hsouna et al. 2023
• Rhizobium acidisoli Román-Ponce et al. 2016
• 埃及根瘤菌 Rhizobium aegyptiacum Shamseldin et al. 2017
• Rhizobium aethiopicum Aserse et al. 2017
• Rhizobium aggregatum (Hirsch and Müller 1986) Kaur et al. 2011
• Rhizobium alamii Berge et al. 2009
• Rhizobium alkalisoli Lu et al. 2009，為Neorhizobium alkalisoli (Lu et al. 2009) Mousavi et al. 2015的異名
• Rhizobium altiplani Baraúna et al. 2016
• Rhizobium alvei Sheu et al. 2015
• 安徽根瘤菌 Rhizobium anhuiense Zhang et al. 2015
• Rhizobium aquaticum Máthé et al. 2019
• Rhizobium arenae Zhang et al. 2017
• Rhizobium arsenicireducens Mohapatra et al. 2020
• Rhizobium azibense Mnasri et al. 2014
• Rhizobium azooxidifex Behrendt et al. 2016
• Rhizobium bangladeshense Rashid et al. 2015
• Rhizobium beringeri Young et al. 2023
• Rhizobium binae Rashid et al. 2015
• Rhizobium borbori Zhang et al. 2011，為Allorhizobium borbori (Zhang et al. 2011) Mousavi et al. 2016的異名
• Rhizobium brockwellii Young et al. 2023
• Rhizobium calliandrae Rincón-Rosales et al. 2013
• Rhizobium capsici Lin et al. 2015
• Rhizobium cauense Liu et al. 2015
• Rhizobium cellulosilyticum García-Fraile et al. 2007
• Rhizobium chutanense Huo et al. 2019
• Rhizobium ciceri Nour et al. 1994，為Mesorhizobium ciceri (Nour et al. 1994) Jarvis et al. 1997的異名
• Rhizobium croatiense Rajnovic et al. 2023
• 大田根瘤菌 Rhizobium daejeonense Quan et al. 2005
• Rhizobium dioscoreae Ouyabe et al. 2020
• Rhizobium ecuadorense Ribeiro et al. 2015
• Rhizobium endolithicum Parag et al. 2014
• Rhizobium endophyticum López-López et al. 2011
• Rhizobium esperanzae Cordeiro et al. 2017
• Rhizobium etli Segovia et al. 1993
• Rhizobium fabae Tian et al. 2008
• Rhizobium favelukesii Torres Tejerizo et al. 2016
• Rhizobium flavum Gu et al. 2014
• Rhizobium fredii Scholla and Elkan 1984，為Ensifer fredii (Scholla and Elkan 1984) Young 2003的異名
• Rhizobium freirei Dall'Agnol et al. 2013
• Rhizobium galegae Lindström 1989，為Neorhizobium galegae (Lindström 1989) Mousavi et al. 2015的異名
• Rhizobium gallicum Amarger et al. 1997
• 格氏根瘤菌 Rhizobium gei Shi et al. 2016
• Rhizobium giardinii Amarger et al. 1997
• Rhizobium grahamii López-López et al. 2012
• 海南根瘤菌 Rhizobium hainanense Chen et al. 1997
• Rhizobium halophytocola Bibi et al. 2012
• Rhizobium helianthi Wei et al. 2015
• Rhizobium herbae Ren et al. 2011，為Pararhizobium herbae (Ren et al. 2011) Mousavi et al. 2016的異名
• Rhizobium hidalgonense Yan et al. 2020
• 華氏根瘤菌 Rhizobium huakuii Chen et al. 1991，為Mesorhizobium huakuii (Chen et al. 1991) Jarvis et al. 1997的異名
• Rhizobium huautlense Wang et al. 1998，為Neorhizobium huautlense (Wang et al. 1998) Mousavi et al. 2015的異名
• Rhizobium indigoferae Wei et al. 2002
• Rhizobium ipomoeae Sheu et al. 2016
• Rhizobium jaguaris Rincón-Rosales et al. 2013
• 日本根瘤菌 Rhizobium japonicum (Kirchner 1896) Buchanan 1926，為Bradyrhizobium japonicum (Kirchner 1896) Jordan 1982的異名
• Rhizobium johnstonii Young et al. 2023
• Rhizobium laguerreae Saïdi et al. 2014
• Rhizobium larrymoorei (Bouzar and Jones 2001) Young 2004，為Agrobacterium larrymoorei Bouzar and Jones 2001的異名
• 豌豆根瘤菌 Rhizobium leguminosarum (Frank 1879) Frank 1889
• Rhizobium lemnae Kittiwongwattana and Thawai 2014
• Rhizobium lentis Rashid et al. 2015
• Rhizobium leucaenae Ribeiro et al. 2012
• Rhizobium loessense Wei et al. 2003，為Rhizobium mongolense subsp. loessense (Wei et al. 2003) Hördt et al. 2020的異名
• Rhizobium loti Jarvis et al. 1982，為Mesorhizobium loti (Jarvis et al. 1982) Jarvis et al. 1997的異名
• Rhizobium lupini (Schroeter 1886) Eckhardt et al. 1931，基異名：Phytomyxa lupini Schroeter 1886
• Rhizobium lusitanum Valverde et al. 2006
• Rhizobium marinum Liu et al. 2015
• Rhizobium mayense Rincón-Rosales et al. 2013
• 地中海根瘤菌 Rhizobium mediterraneum Nour et al. 1995，為Mesorhizobium mediterraneum (Nour et al. 1995) Jarvis et al. 1997的異名
• Rhizobium meliloti Dangeard 1926，為Ensifer meliloti (Dangeard 1926) Young 2003的異名
• Rhizobium mesoamericanum López-López et al. 2012
• Rhizobium mesosinicum Lin et al. 2009
• Rhizobium metallidurans Grison et al. 2015
• Rhizobium miluonense Gu et al. 2008
• 內蒙根瘤菌 Rhizobium mongolense Van Berkum et al. 1998
• Rhizobium multihospitium Han et al. 2008
• Rhizobium naphthalenivorans Kaiya et al. 2018
• Rhizobium nepotum Puławska et al. 2012，為Agrobacterium nepotum (Puławska et al. 2012) Mousavi et al. 2016的異名
• Rhizobium oryzae Peng et al. 2008，為Allorhizobium oryzae (Peng et al. 2008) Mousavi et al. 2016的異名
• 稻生根瘤菌 Rhizobium oryzicola Zhang et al. 2015
• Rhizobium oryziradicis Zhao et al. 2017，為Allorhizobium oryziradicis (Zhao et al. 2017) Lin et al. 2020的異名
• 巴基斯坦根瘤菌 Rhizobium pakistanense Khalid et al. 2015，也拼作：Rhizobium pakistanensis
• Rhizobium paknamense Kittiwongwattana and Thawai 2013
• Rhizobium paranaense Dall'Agnol et al. 2014
• Rhizobium petrolearium Zhang et al. 2012
• Rhizobium phaseoli Dangeard 1926
• Rhizobium pisi Ramírez-Bahena et al. 2008
• Rhizobium populi Rozahon et al. 2014
• Rhizobium populisoli Shen et al. 2022
• Rhizobium pseudoryzae Zhang et al. 2011，為Allorhizobium pseudoryzae (Zhang et al. 2011) Mousavi et al. 2016的異名
• Rhizobium puerariae Boonsnongcheep et al. 2016
• Rhizobium pusense Panday et al. 2011，為Agrobacterium pusense (Panday et al. 2011) Mousavi et al. 2016的異名
• Rhizobium radiobacter (Beijerinck and van Delden 1902) Young et al. 2001，為Agrobacterium radiobacter (Beijerinck and van Delden 1902) Conn, 1942 的異名
• Rhizobium redzepovicii Rajnovic et al. 2023
• Rhizobium rhizogenes (Riker et al. 1930) Young et al. 2001
• Rhizobium rhizophilum Gao et al. 2020
• Rhizobium rhizoryzae Zhang et al. 2014
• Rhizobium rhododendri Kuzmanović et al. 2023
• Rhizobium rosettiformans Kaur et al. 2011
• Rhizobium rubi (Hildebrand 1940) Young et al. 2001，為Agrobacterium rubi (Hildebrand 1940) Starr and Weiss 1943的異名
• Rhizobium ruizarguesonis Jorrin et al. 2020
• Rhizobium selenitireducens Hunter et al. 2008，也拼作：Rhizobium selenireducens
• Rhizobium setariae Kang and Seo 2023
• Rhizobium skierniewicense Puławska et al. 2012
• Rhizobium smilacinae Zhang et al. 2015
• 土壤根瘤菌 Rhizobium soli Yoon et al. 2010
• Rhizobium sophorae Jiao et al. 2015
• Rhizobium sophoriradicis Jiao et al. 2015
• Rhizobium sphaerophysae Xu et al. 2012
• Rhizobium straminoryzae Lin et al. 2014
• Rhizobium subbaraonis Ramana et al. 2013
• Rhizobium sullae Squartini et al. 2002
• 太白山根瘤菌 Rhizobium taibaishanense Yao et al. 2012，為Allorhizobium taibaishanense (Yao et al. 2012) Hördt et al. 2020的異名
• Rhizobium tarimense Turdahon et al. 2013
• 土生根瘤菌 Rhizobium terricola Dahal et al. 2023
• 天山根瘤菌 Rhizobium tianshanense Chen et al. 1995，為Mesorhizobium tianshanense (Chen et al. 1995) Jarvis et al. 1997的異名
• 西藏根瘤菌 Rhizobium tibeticum Hou et al. 2009
• Rhizobium trifolii Dangeard 1926，為Rhizobium leguminosarum (Frank 1879) Frank 1889的異名
• Rhizobium tropici Martínez-Romero et al. 1991
• Rhizobium tubonense Zhang et al. 2011
• Rhizobium tumorigenes Kuzmanović et al. 2019
• Rhizobium undicola (de Lajudie et al. 1998) Young et al. 2001，為Allorhizobium undicola de Lajudie et al. 1998的異名
• Rhizobium vallis Wang et al. 2011
• Rhizobium vignae Ren et al. 2011，為Neorhizobium vignae (Ren et al. 2011) Hördt et al. 2020的異名
• Rhizobium viscosum (Gasdorf et al. 1965) Flores-Félix et al. 2017
• Rhizobium vitis (Ophel and Kerr 1990) Young et al. 2001，為Allorhizobium vitis (Ophel and Kerr 1990) Mousavi et al. 2016的異名
• 文新根瘤菌 Rhizobium wenxiniae Gao et al. 2017，以土壤微生物及細菌分類學家、中國科學院院士陳文新的名字命名
• 梧州根瘤菌 Rhizobium wuzhouense Yuan et al. 2018
• 楊凌根瘤菌 Rhizobium yanglingense Tan et al. 2001
• 鹽亭根瘤菌 Rhizobium yantingense Chen et al. 2015
• Rhizobium zeae Celador-Lera et al. 2017

外部連結

• Current research on Rhizobium leguminosarum （頁面存檔備份，存於互聯網檔案館） at the Norwich Research Park
• Video and commentary on root nodules and Rhizobium in White Clover （頁面存檔備份，存於互聯網檔案館）