Breeding system diversification and evolution in Poa

Species of Poa show an exceptional diversity in breeding systems represented by the occurrence of hermaphroditism to dioecism, with gynomonoecy very frequent among species in South America. Giussani et al. contribute to the understanding of the evolutionary patterns in Poa associated with species sexuality and their current distribution.

Morphological variation among species of Poa supersect. Homalopoa of the New World.
Morphological variation among species of Poa supersect. Homalopoa of the New World. (A) Poa cusickii subsp. purpurascens (clade C); (B) P. unispiculata (clade E); (C) P. bergii (clade D), photo: Daniel Testoni; (D) P. cuspidata; (E) P. aequigluma (clade E); (F) Robert Soreng holding a specimen of P. horridula (clade F); (G) P. lanigera (clade D); clades are given following the results as presented in Supplementary Data Fig. S1. Image by Giussani et al.(2016)

Divergence dating provides a temporal context to the evolution of breeding systems. Infrageneric taxonomic categories in New World Poa supersect. Homalopoa can be accommodated to the phylogenetic results in correlation with reproductive system and geography.

Reference List

Liliana M. Giussani, Lynn J. Gillespie, M. Amalia Scataglini, María A. Negritto, Ana M. Anton, Robert J. Soreng, 2016, 'Breeding system diversification and evolution in American Poa supersect. Homalopoa (Poaceae: Poeae: Poinae)', Annals of Botany, vol. 118, no. 2, pp. 281-303 http://dx.doi.org/10.1093/aob/mcw108