Data from: Phylogeny and photosynthesis of the grass tribe Paniceae

PREMISE OF THE STUDY: The grass tribe Paniceae includes important food,
forage, and bioenergy crops such as switchgrass, napiergrass, various
millet species, and economically important weeds. Paniceae are also
valuable for answering scientific and evolutionary questions about C4
photosynthetic evolution, drought tolerance, and spikelet variation.
However, the phylogeny of the tribe remains incompletely resolved.
METHODS: Forty-five taxa were selected from across the tribe Paniceae and
outgroups for genome survey sequencing (GSS). These data were used to
build a phylogenetic tree of the Paniceae based on 102 markers (78
chloroplast, 22 mitochondrial, 2 nrDNA). Ancestral state reconstruction
analyses were also performed within the Paniceae using both the
traditional and two subtype classification systems to test hypotheses of
C4 subtype evolution. KEY RESULTS: The phylogenetic tree resolves many
areas of the Paniceae with high support and provides insight into the
origin and number of C4 evolution events within the tribe. The recovered
phylogeny and ancestral state reconstructions support between four and
seven independent origins of C4 photosynthesis within the tribe and
indicate which species are potentially the closest C3 sister taxa of each
of these events. CONCLUSIONS: Although the sequence of evolutionary events
that produced multiple C4 subtypes within the Paniceae remains
undetermined, the results presented here are consistent with only a subset
of currently proposed models. The species used in this study constitute a
panel of C3 and C4 grasses that are suitable for further studies on C4
photosynthesis, bioenergy, food and forage crops, and various
developmental features of the Paniceae.