Sem Studies on Spermoderm of some Species of Medicago (Papilionoideae-Trifolieae)

Seeds of 9 species of Medicago have been investigated under light and scanning electron microscope to find out the systematic significance of spermoderm pattern. Under light microscope, the surface is smooth in all the species except M. monantha and M. orbicularis where it is tuberculate. Under scanning electron microscope, majority of species viz., M. laciniata, M. lupulina, M. minima, M. orbicularis. M. polymorpha var. vulgaris and M. × varia show tuberculate (papillose) pattern while M. edgeworthii, M. monantha and M. sativa show false reticulate, reticulate and rugulate patterns respectively. The nature of tubercules differs from species to species and thus spermoderm pattern can be used in the identification of plants at specific level.