Palynological investigation of some selected species of family Fabaceae from Pakistan, using light and scanning electron microscopy techniques

Abstract Pollen morphology of 11 species of family Fabaceae that is, Trifolium alexandrinum , Trifolium resupinatum , Arachis hypogaea , Lathyrus aphaca , Medicago lupulina , Vicia sativa , Lathyrus odoratus , Pongamia pinnata , Melilotus indicus , Medicago polymorpha , Medicago sativa from Pakistan has been investigated by light and scanning electron microscopy. Pollen were generally tricolporate, radially symmetrical, isopolar, elliptic in equatorial view and triangular in polar view under LM. Results showed that pollens were per‐prolate ( T. alexandrinum ), prolate ( T. resupinatum , V. sativa , L. odoratus , Melilotus indicus , M. polymorpha , M. sativa ) and sub‐prolate ( A. hypogaea , L. aphaca , M. lupulina , P. pinnata ). The larger polar/equatorial (P/E) ratio was found in T. alexandrinum (2.26 μm) and the smallest was found in M. lupulina (1.21 μm). The exine of T. resupinatum was 3.00 μm in thickness while others posses smaller exine thickness. The larger pore diameter was found in P. pinnata (16.01 μm) while others have smaller. The length of colpi was larger in Arachis hypogaea (32.24) while others posses smaller. Eight types of surface ornamentation (Psilate, faintly rugulate). Perforate and rugulate to verrucate have been observed under SEM. The pollens were europalynous type. Pollen morphology proved to be useful for the specific delimitation and serve as a tool for the identification and classification of taxa at specific and generic levels and can also be used as a key for the taxonomic features. Diversity in exine sculpture is helpful indicative characters for the isolation of closely related species. Hence, it is clear that both qualitative and quantitative characters of pollen can be useful for differentiating between taxa at specific level.