Editing Boletus edulis (section)

===Mycorrhizal associations===
''Boletus edulis'' is [[mycorrhiza]]l—it is in a [[Mutualism (biology)|mutualistic]] relationship with the roots of plants (hosts), in which the fungus exchanges [[nitrogen]] and other nutrients extracted from the environment for [[carbon fixation|fixed carbon]] from the host. Other benefits for the plant are evident: in the case of the [[Castanea mollissima|Chinese chestnut]], the formation of mycorrhizae with ''B.&nbsp;edulis'' increases the ability of plant seedlings to resist [[moisture stress|water stress]], and increases leaf [[succulent plants|succulence]], leaf area, and water-holding ability.<ref>{{cite journal |vauthors=Quan L, Lei ZP |year=2000 |title=A study on effect of ectomycorrhizae on promoting ''Castanea mollissima'' resistance to drought and its mechanism |journal=Forest Research |volume=13 |issue=3 |pages=249–56 |issn=1001-1498|language=zh}}</ref> The fungus forms a sheath of tissue around terminal, nutrient-absorbing root tips, often inducing a high degree of branching in the tips of the host, and penetrating into the root tissue, forming, to some mycologists, the defining feature of ectomycorrhizal relationships, a [[hartig net]].<ref name="ReferenceA">Smith, Sally; Read, David. Mycorrhizal Symbiosis. Academic press, 1996</ref>  The ectomycorrhizal fungi are then able to exchange nutrients with the plant, effectively expanding the root system of the host plant to the furthest reaches of the symbiont fungi.<ref name="ReferenceA"/> Compatible hosts may belong to multiple families of [[vascular plant]]s that are widely distributed throughout the Northern Hemisphere; according to one 1995 estimate, there are at least 30 host plant species distributed over more than 15 genera.<ref name=Wang1995/> Examples of mycorrhizal associates include [[Pinus massoniana|Chinese red pine]],<ref>{{cite journal |vauthors=Fu SC, Tan Q, Chen MJ, Shang XD, Cai LY, Zhang MY |year=2009 |title=Mycorrhizal synthesis involving ''Boletus edulis'' and ''Pinus massoniana''|journal= Acta Edulis Fungi |volume=16 |issue=1 |pages=31–41 |issn=1005-9873}}</ref> [[Pinus patula|Mexican weeping pine]],<ref>{{cite journal |vauthors=Gross E, Thomazini-Casagrande LI, Caetano FH |year=1998 |title=A scanning electron microscopy study of ectomycorrhizae on ''Pinus patula'' Schiede and Deppe |journal=Naturalia (Rio Claro) |volume=23 |issue=1 |pages=93–101 |issn=0101-1944 }}</ref> [[Scots pine]], [[Picea abies|Norway spruce]],<ref>{{cite journal |vauthors=Ceruti A, Tozzi M, Reitano G |year=1987–88 |title=Micorrize di sintesi tra ''Boletus edulis'', ''Pinus sylvestris'' e ''Picea excelsa''|trans-title=Mycorrhizal synthesis between ''Boletus edulis'', ''Pinus sylvestris'' and ''Picea excelsa''|journal=Allionia (Turin) |volume=28 |pages=117–24|issn=0065-6429|language=it}}</ref> [[Pseudotsuga menziesii|Coast Douglas-fir]],<ref>{{cite journal |author=Gobl F. |year=1977 |title=Mycorrhiza in Austrian Douglas fir stands |journal=Centralblatt für das Gesamte Forstwesen |volume=94 |issue=4 |pages=185–94|issn=0379-5292|language=de}}</ref> [[Pinus mugo|mountain pine]],<ref>{{cite journal |vauthors=Froidevaux L, Amiet R |year=1975 |title= Ecto mycorrhizae endo mycorrhizae of ''Pinus mugo'' plus ''Boletus edulis'' ssp ''edulis'' and ''Pinus cembra'' plus ''Suillus variegatus'' formed in pure culture |journal=European Journal of Forest Pathology |volume=5 |issue=1 |pages=57–61 |issn=0300-1237 |doi=10.1111/j.1439-0329.1975.tb00935.x}}</ref> and [[Pinus virginiana|Virginia pine]].<ref>{{cite journal |vauthors=Vozzo JA, Hackskaylo E |year=1961 |title=Mycorrhizal fungi on ''Pinus virginiana'' |journal=Mycologia |volume=53 |issue=5 |pages=538–39 |doi=10.2307/3756310 |jstor=3756310}}</ref> The fungus has also been shown to associate with [[Cistus ladanifer|gum rockrose]], a [[pioneer species|pioneer]] early stage shrub that is adapted for growth in degraded areas, such as burned forests.<ref name=Agueda2008/> These and other [[Cistus|rockrose]] species are ecologically important as fungal reservoirs, maintaining an inoculum of mycorrhizal fungi for trees that appear later in the [[Ecological succession|forest regrowth cycle]].<ref>{{cite journal |vauthors=Águeda B, Parladé J, de Miguel AM, Martínez-Peña F |year=2006 |title=Characterization and identification of field ectomycorrhizae of ''Boletus edulis'' and ''Cistus ladanifer'' |journal=Mycologia |volume=98 |issue=1 |pages=23–30 |doi=10.3852/mycologia.98.1.23 |pmid=16800301|hdl=10171/18758 |hdl-access=free }}</ref>

The mushroom has been noted to often co-occur with ''[[Amanita muscaria]]'' or ''[[Amanita rubescens|A.&nbsp;rubescens]]'', although it is unclear whether this is due to a biological association between the species, or because of similarities in growing season, habitat, and ecological requirements.<ref name=Hall1998/> An association has also been reported between ''B.&nbsp;edulis'' and ''[[Amanita excelsa var. spissa|Amanita excelsa]]'' on ''[[Pinus radiata]]'' ectomycorrhizae in New Zealand, suggesting that other fungi may influence the life cycle of porcini.<ref>{{cite journal |vauthors=Hall IR, Wang Y, Amicucci A |year=2003 |title=Cultivation of edible ectomycorrhizal mushrooms |journal=Trends in Biotechnology |volume=21 |issue=10|pages=433–38 |doi=10.1016/S0167-7799(03)00204-X|pmid=14512229}}</ref> A 2007 field study revealed little correlation between the abundance of fruit bodies and presence of its mycelia below ground, even when soil samples were taken from directly beneath the mushroom; the study concluded that the triggers leading to formation of mycorrhizae and production of the fruit bodies were more complex.<ref>{{cite journal |vauthors=Peintner U, Iotti M, Klotz P, Bonuso E, Zambonelli A |year=2007 |title=Soil fungal communities in a ''Castanea sativa'' (chestnut) forest producing large quantities of ''Boletus edulis sensu lato'' (porcini): where is the mycelium of porcini? |journal=Environmental Microbiology |volume=9 |issue=4 |pages=880–89 |doi=10.1111/j.1462-2920.2006.01208.x|pmid=17359260}}</ref>