Morphological and palynological assessment of some taxa of genus Echinochloa through light and scanning electron microscopy.

The present study was undertaken to gather information on selected species of Echinochloa based on their morphological and palyonological examination through light and scanning electron microscopy. As the Echinochloa species are most problematic grass weeds and exhibit high interspecific and intraspecific variability so due to their great morphological diversity it is difficult to recognize them. A lot of variation was observed in morphological features of studied taxa. In the present study, E. colona had more or less spreading dense racemes whereas in E. crus-galli racemes were linear to ovate. Upper glume surface was pubescent in E. colona, hispid in E. crus-galli and spinose in E. walteri. E. colona was comprised of five-nerved glumes whereas in E. crus-galli glumes were three-nerved. Although pollen basic characters in family Poaceae remains consistent but great variation was observed in pollen of studied taxa. The pollen size was quite variable among the species of genus Echinochloa. In polar view, the size of pollen grains ranged from 27.5 (20-35) µm to 40 (30-50) µm. E. crus-galli was appeared to be the smallest in size whereas E. colona was the largest.). P/E ratio ranged from 0.84 to 1.15 µm among the species. The highest value of pollen fertility was found in E. colona as 93.33% and lowest was in E. crus-galli as 87.50%. The morphological key of studied taxa is also given to study variations. In conclusion, it was observed that microscopy of morphological and palynological assessment can play a vital role in identification of taxonomically problematic taxa.

Pollen morphological assessment of specific selected species of district Sheikhupura, Punjab, Pakistan under LM and SEM.

Around 30 pollen samples, 16 families and 25 genera that were gathered, identified and preserved from 6 different localities of District Sheikhupura. Light and scanning electron microscopy was done for all collected flora. Out of the total samples, 43% specie was identified as herbs, 23% as shrubs, and 33% were identified as trees. The flora was both wild and cultivated. Wild plants were 33%, cultivated 40% and 26% of them were both wild and cultivated. Qualitative and Quantitative survey of pollens revealed polar shape of pollens were 37% spheroidal, 20% prolate spheroidal, 17% oblate spheroidal, remaining were rectangular and pecolpate. Sexine and nexine were available in 100% of samples. Thirty-three percentage of pollen grains were having spines on them. The presence of spines on pollen grains represents the evolutionary relationship amongst the plants. Current study was conducted to record and analyze palynomorphic diversity in district Sheikhupura, Punjab, Pakistan.

Scanning Electron Microscopy-based palynological characterization of selected Euphorbiaceae taxa colonized in Pakistan.

The present study was carried out on scanning electron microscopic-based palynological characterization of selected 20 Euphorbiaceae taxa. In this study, important pollen qualitative and quantitative features of selected Euphorbiaceae species such as polar diameter, equatorial diameter, P/E ratio, sculpturing of pollen, exine thickness, intine thickness, presence or absence of colpi and length of colpi, and pollen fertility were examined. Remarkable variations in these pollen characters had been observed among these species. In both polar and equatorial views, Riccinus communis L. exhibited the highest pollen size (polar = 264.1 µm, Equatorial = 270 µm), while Acalypha wilkesiana Mull Arg. showed lowest pollen size (Polar = 17 µm, Equatorial = 18.5 µm). Most of the pollen varied from oblate to spheroidal in shape. With regard to the P/E ratio, Sapium sebiferum L. Roxb showed the highest ratio while Bischofia javanica Blume showed minimum, that is, 1.18 and 0.85, respectively. Intine and exine thickness also varied. Most of the pollen grains were monade. Tricolporate, tricolpate, monocolpate, pentaporate, and polyporate pollen aperture types have been observed. Most of the plants showed regular, reticulate, and echinate pollen sculpturing. Pollen fertility also varied from species to species but most of the plant showed pollen fertility between 70 and 80%. Through this work, it has been concluded that quantitative and qualitative pollen features are helpful at the specific level as well as the generic level and can provide a fruitful taxonomic solution.