What is Dryadoideae?
{{taxobox |name = Dryadoideae |image = Dryas drummondii6.jpg |image_caption = ''Dryas × suendermannii'' |regnum = [[Plant]]ae |unranked_divisio = [[Angiosperms]] |unranked_classis = [[Eudicots]] |unranked_ordo = [[Rosids]] |ordo = [[Rosales]] |familia = [[Rosaceae]] |subfamilia = '''Dryadoideae''' |subfamilia_authority = ([[Jean-Baptiste Lamarck|Lam.]] & [[Augustin Pyramus de Candolle|DC.]]) [[Robert Sweet (botanist)|Sweet]] |subdivision_ranks = [[Genus|Genera]] |subdivision = ''[[Cercocarpus]]'' [[Carl Sigismund Kunth|Kunth]]<br> ''[[Chamaebatia]]'' [[George Bentham|Benth.]]<br> ''[[Dryas (plant)|Dryas]]'' [[Carolus Linnaeus|L.]]<br> ''[[Purshia]]'' [[Augustin Pyramus de Candolle|DC.]] ex [[Jean Louis Marie Poiret|Poir.]] (including ''Cowania'') |}} The '''Dryadoideae''' subfamily of the [[Rosaceae]] consists of four [[genus|genera]].<ref name=Potter>Potter, D., et al. (2007). Phylogeny and classification of Rosaceae. ''Plant Systematics and Evolution''. 266(1–2): 5–43.</ref> These genera are unusual in the [[family (biology)|family]] Rosaceae because they all have the [[nitrogen fixation|nitrogen-fixing]] [[bacteria]] called ''[[Frankia]]'' in their roots.<ref>Swensen, S.M.; Mullin, B.C. (1997). The impact of molecular systematics on hypotheses for the evolution of root nodule symbioses and implications for expanding symbioses to new host plant genera. ''Plant and Soil''. 194: 185–192.</ref> Dryadoideae plants are [[subshrub]]s, [[shrub]]s, or small [[tree]]s. Their fruits are either an [[achene]] or an [[compound fruit|aggregate]] of achenes.<ref name=Potter/> ==Notes== <references/> [[Category:Rosaceae]] {{biology-stub}}