Abstract
This study was carried out to identify 20 high valued medicinal plants of District Lahore, Punjab, Pakistan with the help of the palynological studies. The distinguishing characteristics for selected species were found by systematized methods using light microscopy and Scanning Electron Microscopy. In this study, important pollen qualitative and quantitative features of these medicinal species such as polar and equatorial outline and their diameter, P/E ratio, presence or absence of pore, sculpturing of pollen, exine thickness, intine thickness, intercellular distance of exine and intine, presence or absence of spines, length of spines, width of spines, presence or absence of colpi and length of colpi, were compared. Remarkable variations in these pollen characters have been observed. Pollen grains were usually circular-semicircular (Calendula officinalis), spheroidal (Convolvulus arvensis), bilobed and trilobed (Convolvulus arvensis), spiny, (Abutilon indicum), oblate (Terminalia chebula) and elongated (Euphorbia pilulifera). In polar view Conyza bonariensis exhibited the highest pollen size [195.9 (211.6-180.2) μm]. While in equatorial view Calendula officinalis and Euphorbia pilulifera had lowest value [22.5 (20-25) μm] whereas Carissa carandas [165 (140-179) μm] appeared to be the largest. Parthenium hysterophorus showed the highest P/E ratio, that is, 1.28. Colpi were reported in only 7 species. Most of the plants showed 100% fertility but Terminalia chebula showed the least value 35%. In the present, project the diversity in pollen morphology present pollen as a valuable taxonomic tool. It is also concluded that pollen features are helpful at the specific level as well as generic level and can provide us fruitful taxonomic solutions. RESEARCH HIGHLIGHTS: Palynological flora of the medicinal plant species of district Lahore, Pakistan is investigated first time on the basis of LM and SEM and the flora is found very significant for taxonomic investigations.