4TH International Congress on Technology - Engineering & SCIENCE - Kuala Lumpur - Malaysia (2017-08-05)
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Evolutionary Trends In Palynological Studies Of Family Polygonaceae From Pakistan
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Comprehensive palynological studies of 47 species belonging to 7 genera of Polygonaceae from Pakistan through scanning electron microscope (SEM) showed significant diversity in the pollen characters including shape and size, aperture number, colpi length, exine thickness and sculpturing. Present pollen study showed that the family Polygonaceae is eurypalynous family especially in aperture number and exine ultrastructure On the basis of these two characters, 14 main pollen types and 6 subtypes have been suggested. Maximum variation related to aperture number is examined in Persicaria species where pollen grains are tricolpate and pantoporate while related to sculpturing two main pollen types, each divided into three subtypes have been observed in the genus. Three parallel directions have been proposed to show the evolutionary trends in presently investigated 14 pollen types of seven genera considering Aconogonon type as primitive one because of tricolpate pollen with microspinulose type of sculpturing. Also, pollen micromorphological characters are generally distinct at generic level and in most cases pollen types varied from one species to another in the same genus. Present results (with limited geographical areas) suggest that pollen morphology of the family Polygonaceae from Pakistan can be used to establish phylogenetic lines when used in combination with other evidences derived from morphology, cytology, anatomy and geographical distribution.
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Ghazalah Yasmin, Mir Ajab Khan
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