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杜鹃花菌根

维基百科,自由的百科全书
Epacris pulchella英语Epacris pulchella,一种产于东澳的杜鹃花科植物。
长柱杜鹃英语Rhododendron occidentale是一种产于北美西方的杜鹃花菌根共生植物。

杜鹃花菌根是一类和杜鹃花科植物共生的内生菌根真菌,杜鹃花科植物通常生活在北方针叶林沼泽石楠荒原等酸性贫脊的土壤,因此这种共生关系对杜鹃花科植物适应环境十分重要[1]。经过分子钟技术推定这种共生关系大约起源于1.4亿年前[2]

构造和功能[编辑]

杜鹃花科植物的是浅根性植物,根系分布很浅,根部没有根毛但有极细的发根英语hair root能让杜鹃花菌根共生,菌根疏松的包附在根部的表皮细胞上后穿入皮层并在细胞间产生菌丝圈来将细胞紧紧包附[3],且通常只包裹住单个细胞[3],但并不穿入细胞膜。菌丝圈通常只能持续几周,不久后便会崩坏分解[3]

菌丝圈是真菌和植物用来交换养分的场所,菌根提供来自土壤的养分而植物提供光合作用的糖类。杜鹃花菌根具有产生酵素来分解复杂有机物的能力[4][5],这让一些菌根具有腐生能力,能取得有机上的营养,例如氮,这些矿物元素在杜鹃花科植物生长的环境是十分缺乏的。[5]

种类[编辑]

Woollsia pungens分离的杜鹃花菌根Gamarada debralockiae。[6]

目前对杜鹃花菌根主要的生理功能研究在于Rhizoscyphus ericae所分离下来的型态鉴定,Rhizoscyphus ericae原属于囊菌刚的柔膜菌目[3],但现在归类在Pezoloma [7]。除了Rhizoscyphus ericae外,目前可以培养子囊菌类的杜鹃花菌根有Meliniomyces (似Rhizoscyphus ericae), Cairneyella variabilis, Gamarada debralockiaeOidiodendron maius [3][8][9][10] 。DNA定序分析揭露了杜鹃花根系的真菌族群多样性,但有可能包含其他非菌根真菌、腐生菌或寄生菌[11][12][13][14]

除了子囊菌类外,亦有一些担子菌类锈革孔菌目的杜鹃花菌根,但无法培养[11][12][15][16]

分布[编辑]

杜鹃花科植物广泛分布在全世界(除了南极洲以外),因此与其共生的菌根也广泛分部在全世界[17]。然而,有少数杜鹃花科植物并没有和杜鹃花菌根共生,而是形成其他种类的菌根,包含manzanita (Arctostaphylos)、madrone (Arbutus)和Monotropoidiae[3]。 这些菌根的分布范围仍然不确定,因为找寻这些真菌的共生植物并不容易[3],例如 Rhizoscyphus ericae 在南北半球都有分布,但目前并没有细分,目前有研究发现此类菌根有些的专一性不高,因此推测有些菌根据有较大的寄主范围[13][14]

经济重要性[编辑]

杜鹃花菌根和多种作物及观赏植物产生共生关系,包含蓝莓、小红莓和杜鹃花属植物,能增加植物吸收营养的能力。[18]

小红莓是一种和杜鹃花菌根共生的作物。
Northern highbush blueberries, Vaccinium corymbosum, an ericoid mycorrhizal crop

外部链接[编辑]

参考资料[编辑]

  1. ^ Cairney, J. W. G. and A. A. Meharg. 2003. Ericoid mycorrhiza: a partnership that exploits harsh edaphic conditions. European Journal of Soil Science 54: 735–740. doi:10.1046/j.1351-0754.2003.0555.x.
  2. ^ Cullings, K. W. 1996. Single phylogenetic origin of ericoid mycorrhizae within the Ericaceae. Canadian Journal of Botany 74: 1896-1909.
  3. ^ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 Smith, S. E. and D. J. Read. 2008. Mycorrhizal Symbiosis, Third Edition. Academic Press.
  4. ^ Cairney, J. W. G., and R. M. Burke.1998. Extracellular enzyme activities of the ericoid mycorrhizal endophyte Hymenoscyphus ericae (Read) Korf & Kernan: their likely roles in decomposition of dead plant tissue in soil. Plant and Soil 205: 181-192.
  5. ^ 5.0 5.1 Read, D. J., J. R. Leake, and J. Perez-Moreno. 2004. Mycorrhizal fungi as drivers of ecosystem processes in heathland and boreal forest biomes. Canadian Journal of Botany 82: 1243-1263.
  6. ^ Midgley, D. J.; Chambers, S. M.; Cairney, J. W. G. Spatial distribution of fungal endophyte genotypes in a Woollsia pungens (Ericaceae) root system. Australian Journal of Botany. 2002, 50 (5): 559. doi:10.1071/BT02020. 
  7. ^ Baral HO and Berbee L. (2006) Hymenoscyphus subcarneus, a little known bryicolous discomycete found in the Białowieża National Park. Acta Mycologia 41:11-20.
  8. ^ Hambleton S, Sigler L (2005) Meliniomyces, a new anamorph genus for root-associated fungi with phylogenetic affinities to Rhizoscyphus ericae (≡ Hymenoscyphus ericae), Leotiomycetes. Studies in Mycology. 53:1-27.
  9. ^ Midgley, D.J., Rosewarne, C.P., Greenfield, P., Li, D., Vockler, C.J., Hitchcock, C.J., Sawyer, N.A., Brett, R., Edwards, J., Pitt, J.I. & Tran-Dinh, N. (2016). Genomic insights into the carbohydrate catabolism of Cairneyella variabilis gen. nov., sp. nov., the first reports from a genome of an ericoid mycorrhizal fungus. Mycorrhiza, 26: 345–352.
  10. ^ Midgley, D.J., Sutcliffe B, Greenfield P & Tran-Dinh, N. (2018) Gamarada debralockiae gen. nov. sp. nov.—the genome of the most widespread Australian ericoid mycorrhizal fungus. Mycorhiza, 28: 379-389.
  11. ^ 11.0 11.1 Allen, T. R., T. Millar, S. M. Berch, and M. L. Berbee. 2003. Culturing and direct DNA extraction find different fungi from the same ericoid mycorrhizal roots. New Phytologist 160:255-272.
  12. ^ 12.0 12.1 Selosse, M. A., S. Setaro, F. Glatard, F. Richard, C. Urcelay, and M. Weiss. 2007. Sebacinales are common mycorrhizal associates of Ericaceae. New Phytologist 174:864-878.
  13. ^ 13.0 13.1 Kjoller, R., M. Olsrud, and A. Michelsen. 2010. Co-existing ericaceous plant species in a subarctic mire community share fungal root endophytes. Fungal Ecology 3:205-214.
  14. ^ 14.0 14.1 Walker, J. F., L. Aldrich-Wolfe, A. Riffel, H. Barbare, N. B. Simpson, J. Trowbridge, and A. Jumpponen. 2011. Diverse Helotiales associated with the roots of three species of Arctic Ericaceae provide no evidence for host specificity. New Phytologist 191: 515-527.
  15. ^ Vohník M, Pánek M, Fehrer J, Selosse M-A (2016) Experimental evidence of ericoid mycorrhizal potential within Serendipitaceae (Sebacinales). Mycorrhiza 26:831–846
  16. ^ Kolarik M, Vohnik M (2018) When the ribosomal DNA does not tell the truth: the case of the taxonomic position of Kurtia argillacea, an ericoid mycorrhizal fungus residing among Hymenochaetales. Fungal Biology 122:1–18
  17. ^ 存档副本. [2019-12-06]. (原始内容存档于2020-05-22). 
  18. ^ Scagel, C. F. 2005 Inoculation with ericoid mycorrhizal fungi alters fertilizer use of highbush blueberry cultivars. HortScience 40: 786-794.