Evolutionary relationships in Panicoid grasses based on plastome phylogenomics (Panicoideae; Poaceae).
Panicoideae are the second largest subfamily in Poaceae (grass family), with 212 genera and approximately 3316 species. Previous studies have begun to reveal relationships within the subfamily, but largely lack resolution and/or robust support for certain tribal and subtribal groups. This study aims to resolve these relationships, as well as characterize a putative mitochondrial insert in one linage.



35 newly sequenced Panicoideae plastomes were combined in a phylogenomic study with 37 other species: 15 Panicoideae and 22 from outgroups. A robust Panicoideae topology largely congruent with previous studies was obtained, but with some incongruences with previously reported subtribal relationships. A mitochondrial DNA (mtDNA) to plastid DNA (ptDNA) transfer was discovered in the Paspalum lineage.



The phylogenomic analysis returned a topology that largely supports previous studies. Five previously recognized subtribes appear on the topology to be non-monophyletic. Additionally, evidence for mtDNA to ptDNA transfer was identified in both Paspalum fimbriatum and P. dilatatum, and suggests a single rare event that took place in a common progenitor. Finally, the framework from this study can guide larger whole plastome sampling to discern the relationships in Cyperochloeae, Steyermarkochloeae, Gynerieae, and other incertae sedis taxa that are weakly supported or unresolved.
Department of Biological Sciences, Northern Illinois University, 1425 W. Lincoln Hwy, DeKalb, IL, 60115-2861, USA. sburke5@niu.edu.
Sean V
SV
Burke
Department of Biological Sciences, Northern Illinois University, 1425 W. Lincoln Hwy, DeKalb, IL, 60115-2861, USA.
William P
WP
Wysocki
Instituto de Botánica Darwinion, Labardén 200, Casilla de Correo 22, B1642HYD, San Isidro, Buenos Aires, Argentina.
Fernando O
FO
Zuloaga
Jonah Ventures, Manhattan, KS, 66502, USA.
Joseph M
JM
Craine
Biological Sciences, University of Missouri, 371b Bond Life Sciences Center, Columbia, MO, 65211, USA.
J Chris
JC
Pires
Department of Horticulture, Michigan State University, East Lansing, MI, 48823, USA.
Patrick P
PP
Edger
Donald Danforth Plant Science Center, 975 North Warson Rd, St. Louis, MO, 63132, USA.
Dustin
D
Mayfield-Jones
Ecology, Evolution and Organismal Biology, 251 Bessey Hall, Iowa State University, Ames, IA, 50011-1020, USA.
Lynn G
LG
Clark
Biological Sciences, Idaho State University, 921 S. 8th Ave, Pocatello, ID, 83209-8007, USA.
Scot A
SA
Kelchner
Department of Biological Sciences, Northern Illinois University, 1425 W. Lincoln Hwy, DeKalb, IL, 60115-2861, USA.
Melvin R
MR
Duvall
D004272:DNA, Mitochondrial / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D019143:Evolution, Molecular; D010802:Phylogeny; D018087:Plastids / Q000235:genetics*; D006109:Poaceae / Q000145:classification / Q000235:genetics*
D004272:DNA, Mitochondrial; D018744:DNA, Plant
Grasses; Next generation sequencing; Panicoideae; Paspalum; Phylogenomics; Plastome; Poaceae; Subtribal systematics; mtDNA; ptDNA