Ecology, evolution and development (eco-evo-devo): the role played by fusoid cells in the diversification of Poaceae (Poales)

Abstract

Poaceae is widely distributed and comprises about 12,000 species in 12 subfamilies. Fusoid cells are originated from the ground meristem and have been reported in leaf blades of many grass species in seven subfamilies: early-diverging lineages Anomochlooideae, Pharoideae, Puelioideae; Oryzoideae, Bambusoideae and Pooideae (BOP clade); and Panicoideae (PACMAD). Grass anatomical studies and greenhouse observations have suggested that the development of fusoid cells is influenced by lighting availability, since these cells occur primarily in shade-friendly grasses. A putative programmed cell death (PCD) process has been also suggested, since fusoid cells collapse during their development and thus die at maturity. In this context, this project aims to study the leaf development of Poaceae species with focus on fusoid cells, involving concepts of ecology and evolution (eco-evo-devo) in order to elucidate the role of these cells in the diversification of Poaceae. Experiments will be carried out to test hypotheses of plastic developmental potential and ancestral potential influenced by lighting availability, as well as the occurrence of a PCD process. The results will allow evolutionary interpretations within Poaceae and will be the key for understanding the role played by fusoid cells in the grass leaf.