A total of 16 different allergenic and invasive weed species belonging to 12 different
families collected from different areas of study. Among the studied plants, most of the
species belong to the Asteraceae family. For morphological studies of pollen through light
microscope (LM) and scanning electron microscope (SEM), the samples were prepared via
acetalization process. We done the fieldwork for the collection of weed plants and also
performed the experimental work i.e. SEM and LM for the pollen morphology. Most of the
species recorded with pollen of tricolporate and echinate. Species belonging to Asteraceae
were considered as most abundant and allergenic as compared to others. The maximum
polar diameter was noted in the Convolvulus arvensis L. is 40.00 μm and the minimum were
noted in Oxalis corniculata is 6.15 μm. Maximum outer layer thickness was noted in
convolvulus arvensis is 3.70 μm and Minimum were noted in Sorghum halepense is 1.65
μm. It was noticed that most of the allergenic and invasive weeds found in plain areas of
Lakki Marwat during September and April. Present study provides information about the
allergenic and invasive weeds plants and their threats to biodiversity. The pollen of such
weed plants causes asthma and atopy disease in humans, and also cause many other
diseases in other living organism.