Identification of breeding system of some species of Verbascum (Scrophulariaceae) in north- west of Iran on the basis of the ratio of Pollen to ovule number

The breeding system of four species V. szovitsianum Boiss., V. cheirantifolium Boiss., V. macrocarpum Lam., and V. mucronatum Lam. were estimated.The number of pollen grains per flower, the number of ovules per flower, and the pollen:ovule ratios in four populations per species (two populations for V.macrocarpum &V. mucronatum) were calculated.Maximum and minimum average pollen grains were found in V. macrocarpum(36750/0 ±4304/5)andV.szovitsianum (251200±24374/9) respectively. The results suggest that all of the studied species have facultative outcrossing and need to pollinators.