Light and scanning electron microscopic imaging of leaf transverse sections of indigenous fodder grasses of central Punjab, Pakistan

The significance of grasses as fodder is enormous. However, it has been observed that different fodder grasses are identified locally with the similar vernacular names. Even same species recognized with different names. This happened due to their reduced and overlapped morphological characters. Hence comprehensive taxonomic keys were required to provide authentic identification of this grass flora. Current study established microscopic identification tools on the basis of leaf transverse anatomical features. Results demonstrated a great diversity in ribs and furrows arrangement among all studied grass members. Lolium temulentum, Phalaris minor, Poa annua, Arundo donax, Aristida adscensionis, Desmostachya bipinnata, Cenchrus biflorus and Digitaria ciliaris possessed ribs and furrows only at adaxial surfaces whereas all other species possessed this feature abaxially. Generally all the species contain three types of vascular bundles i.e. small, medium and large. Therefore, this qualitative feature is valuable only at family level, however, it found insignificant in taxa identification. Diversity was observed in bundle sheath type which could be taxonomically significant. Generally bundle sheath was found complete in most of species but in Bromus japonicus Thunb., Dactylis glomerata L., Acrachne racemosa (Heyne ex Roth) Ohwi, Chrysopogon aucheri (Boiss.) Stapf, Dichanthium annulatum (Forssk.) Stapf, Heteropogon contortus (L.) P Beauv. Ex. Roem & Schult. Eragrostis minor Host. and in Agrostis gigantea Roth. had incomplete type of sheath. Results reported great diversity in characters which could be taxonomically viable. RESEARCH HIGHLIGHTS: This research highlighted the significance of microscopic examination of leaf transverse anatomical features in field of taxonomy. Established anatomical tools would be of great importance for the identification of studied species.