Seed and Plant Improvement Institute. Karaj, Iran.
Pollen grain morphology of 15 taxa of the Hedysareae tribe distributed throughout Iran was studied using light and electron microscopy to identify major taxonomical characteristics of pollen grains. The pollen grains were tricolpate and tricolporate, prolate and perprolate. The ectocolpi were elongated, shallow or deep, narrowing at the poles. The colpus membrane was covered by large granules. Ornamentation was reticulate, and lumina differed in shape and size. In equatorial view, the pollen grains were elongated, elliptic to rectangular-obtuse, while in polar view they were circular, triangular-obtuse or triangular and trilobed. Two pollen types with two tentative subtypes were identified based on ornamentation and polar view.