Pollen and seed morphology of diploids and natural tetraploids of Trifolium pratense L. [Leguminosae]

Pollen and seed morphology were examined in diploids (2n = 14) and natural tetraploids (2n = 28) of Trifolium pratense L. The pollen morphology was generally correlated with ploidy level. Great variety in pollen size and apertures was noted in the tetraploid form. Exine structure was studied by TEM. Seed size, color and coat surface ornamentation can be distinguished between the diploid and tetraploid forms.