The Andropogoneae, sometimes called the sorghum tribe, are a large tribe of grasses (family Poaceae) with roughly 1,200 species in 90 genera, mainly distributed in tropical and subtropical areas. They include such important crops as maize (corn), sugarcane, and sorghum.Also called "kaoliang": "Shensi", in The Columbia-Viking Encyclopedia (1953), New York: Viking. Another spelling is "gaoliang." All species in this tribe use C4 carbon fixation, which makes them competitive under warm, high-light conditions.
Andropogoneae is classified in supertribe Andropogonodae, together with its sister group Arundinelleae. Subdivisions include 12 subtribes, but the position of several genera within them is still unresolved (incertae sedis). Hybridisation was probably important in the evolution of the Andropogoneae, and the tribe's systematics are still not completely resolved. From the morphological point of view, the merging of the former subtribe 'Dimeriinae' (having solitary spikelets borne in 'robust' raceme rachis) into the subtribe Ischaeminae (having paired spikelets borne in 'fragile' raceme rachis) is doubtful. Affinities within the tribe are complex and still under investigation. Shahid Nawaz, a grass specialist at the Blatter Herbarium, is working on the phylogenomics of the tribe from India.
According to preliminary phytogeographic research on the tribe by M.S. Kiran Raj, Peninsular India, home to 54 genera (including nine endemic genera, viz., Bhidea, Lophopogon, Glyphochloa, Pogonachne, Trilobachne, Pseudodichanthium, Triplopogon, Nanooravia, and Manisuris) and roughly 500 species, is thought to be the primary or secondary centre of diversity for Andropogonoid grasses. About 40% of the representative taxa are exclusively endemic to peninsular India, with the highest species diversity and endemicity found in genera like Arthraxon, Chrysopogon, Cymbopogon, Dichanthium, Dimeria, Heteropogon, Ischaemum, Ophiorus, Sehima, and Themeda.
Description Spikelets within the inflorescence (flower cluster) are generally arranged on spicate racemes in pairs. A fertile, unstalked spikelet is subtended by a sterile, stalked spikelet. In species where awns are present they are found on the fertile, unstalked spikelet as an extension of the lemma.
Subtribes and genera 2017 classification Classification following Soreng et al. (2017):
2020 classification Classification following Welker et al. (2020) (one asterisk * marks genera not sampled in their analyses that were tentatively placed based on previously published phylogenetic analyses; two asterisks ** marks genera placed solely on morphology):
Tribe Andropogoneae – 14 subtribes, 92 genera, and about 1224 species Subtribe Arthraxoninae – 1 genus and about 27 species Arthraxon – 27 species Subtribe Tripsacinae – 2 genera and about 23 species Tripsacum – 16 species Zea – 7 species Subtribe Chionachninae – 3 genera and about 12 species Chionachne – 9 species Polytoca – 2 species Trilobachne – 1 species ** Subtribe Rhytachninae – 5 genera and about 26 species Loxodera – 5 species Oxyrhachis – 1 species Rhytachne – 12 species Urelytrum – 7 species Vossia – 1 species Subtribe Chrysopogoninae – 1 genus and about 49 species Chrysopogon – 49 species Subtribe Rottboelliinae = Coicinae – 3 genera and about 13 species Chasmopodium – 3 species * Coix – 4 species Rottboellia – 6 species Subtribe Ratzeburgiinae – 11 genera and about 87 species Eremochloa – 12 species Glyphochloa – 9 species Hackelochloa – 2 species Hemarthria – 14 species Heteropholis – 6 species * Manisuris – 1 species * Mnesithea – 26 species Ophiuros – 4 species * Ratzeburgia – 1 species ** Thaumastochloa – 8 species * Thyrsia – 4 species Subtribe Ischaeminae = Dimeriinae – 4 genera and about 152 species Andropterum – 1 species Dimeria – 61 species Eulaliopsis – 2 species Ischaemum – 88 species Subtribe Germainiinae – 5 genera and about 44 species Apocopis – 16 species * Germainia – 10 species Imperata – 13 species Lophopogon – 2 species ** Pogonatherum – 3 species Subtribe Sorghinae – 4 genera and about 37 species Cleistachne – 1 species Lasiorhachis – 3 species Sarga – 9 species Sorghum – 24 species Subtribe Saccharinae – 3 genera and about 64 species Miscanthus – 30 species Pseudosorghum – 2 species Saccharum – 32 species Subtribe Apludinae – 7 genera and about 68 species Apluda – 1 species Asthenochloa – 1 species ** Eulalia – 34 species Homozeugos – 6 species Polytrias – 1 species Sorghastrum – 21 species Trachypogon – 4 species Subtribe Anthistiriinae – 9 genera and about 204 species Bothriochloa – 37 species Capillipedium – 18 species Cymbopogon – 59 species Dichanthium – 22 species Eremopogon – 4 species * Euclasta – 2 species Heteropogon – 6 species Iseilema – 24 species Themeda – 32 species Subtribe Andropogoninae – 11 genera and about 292 species Anadelphia – 14 species Andropogon – 125 species Bhidea – 3 species ** Diectomis – 1 species Diheteropogon – 4 species Elymandra – 6 species Exotheca – 1 species Hyparrhenia – 58 species Hyperthelia – 7 species Monocymbium – 3 species Schizachyrium – 70 species Incertae sedis – 23 genera and about 126 species Agenium – 4 species * Elionurus – 17 species Eriochrysis – 11 species Jardinea – 3 species Kerriochloa – 1 species Lasiurus – 1 species Leptatherum – 3 species * Microstegium – 27 species Parahyparrhenia – 6 species Phacelurus – 6 species * Pseudopogonatherum – 5 species * Sehima – 5 species Spodiopogon – 18 species * Thelepogon – 2 species Tripidium – 6 species Clausospicula – 1 species ** Lakshmia – 1 species ** Pogonachne – 1 species ** Pseudanthistiria – 4 species ** Pseudodichanthium – 1 species ** Spathia – 1 species ** Triplopogon – 1 species ** Veldkampia – 1 species **
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