Pollen Grain Morphology of Some Selected Species of Asteraceae in South Western Nigeria

Pollen morphology and diversity of twelve species of the Asteraceae were collected from different locations within Ile-Ife, South Western Nigeria and acetolysed. The parameters used for the characterization are: diameter of pollen grains, pollen wall thickness, number of pores, thickness between pores, length of spines and number of colpi. The pollen grains of the species studied are spheroidal in shape, in the group media and minuta, either echinate or spinate, yellow to yellowish brown, polypentaporate, tricolporate, acolpate and polycolporate, spines are short with thin walls and pores are densely situated and the measurements taken showed variations from species to species. The similarities in structure showed interspecies relationships and reasons for them to be in the same family while the interspecific variations in structures substantiate their existence as distinct species