Chloridoideae

Chloridoideae is one of the largest subfamilies of grasses, with roughly 150 genera and 1,600 species, mainly found in arid tropical or subtropical grasslands. Within the PACMAD clade, their sister group are the Danthonioideae.[1] The subfamily includes widespread weeds such as Bermuda grass (Cynodon dactylon) or goosegrass (Eleusine indica), but also millet species grown in some tropical regions, namely finger millet (Eleusine coracana) and teff (Eragrostis tef).

Chloridoideae
Millet fields in Annapurna.png
Finger millet (Eleusine coracana) in Nepal
Scientific classification e
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Clade: Commelinids
Order: Poales
Family: Poaceae
Clade: PACMAD clade
Subfamily: Chloridoideae
Kunth ex Beilschm.
Tribes

With the exception of some species in Ellisochloa and Eleusine indica, most of the subfamily's species use the C4 photosynthetic pathway. The first evolutionary transition from C3 to C4 photosynthesis in the grasses probably occurred in this subfamily, around 32 to 25 million years ago in the Oligocene.[2]

PhylogenyEdit

Relationships of tribes in the Chloridoideae according to a 2017 phylogenetic classification, also showing the Danthonioideae as sister group:[3]

Danthonioideae

Chloridoideae

Centropodieae

Triraphideae

Eragrostideae

Cynodonteae

Zoysieae

The following genera have not been assigned to a tribe:[3]

ReferencesEdit

  1. ^ Soreng, Robert J.; Peterson, Paul M.; Romschenko, Konstantin; Davidse, Gerrit; Zuloaga, Fernando O.; Judziewicz, Emmet J.; Filgueiras, Tarciso S.; Davis, Jerrold I.; Morrone, Osvaldo (2015). "A worldwide phylogenetic classification of the Poaceae (Gramineae)". Journal of Systematics and Evolution. 53 (2): 117–137. doi:10.1111/jse.12150. ISSN 1674-4918.  
  2. ^ Christin, Pascal-Antoine; Besnard, Guillaume; Samaritani, Emanuela; Duvall, Melvin R.; Hodkinson, Trevor R.; Savolainen, Vincent; Salamin, Nicolas (2008). "Oligocene CO2 Decline Promoted C4 Photosynthesis in Grasses". Current Biology. 18 (1): 37–43. doi:10.1016/j.cub.2007.11.058. hdl:2262/82791. ISSN 0960-9822. PMID 18160293.  
  3. ^ a b Soreng, Robert J.; Peterson, Paul M.; Romaschenko, Konstantin; Davidse, Gerrit; Teisher, Jordan K.; Clark, Lynn G.; Barberá, Patricia; Gillespie, Lynn J.; Zuloaga, Fernando O. (2017). "A worldwide phylogenetic classification of the Poaceae (Gramineae) II: An update and a comparison of two 2015 classifications". Journal of Systematics and Evolution. 55 (4): 259–290. doi:10.1111/jse.12262. ISSN 1674-4918.