Pollen morphology of Ipomoea L. from Garhwal Himalaya, India

Abstract

Pollen morphology serves as a valuable tool for identification, phylogenetic analysis and evolutionary studies. The present study aims to investigate the pollen morphology of 12 species of the genus Ipomoea L. (a diverse and economically important genus within the family Convolvulaceae) from Garhwal Himalaya, India. Fresh flower buds were collected from the study area and pollen preparation completed using the acetolysis method. The morphology of the pollen grains were examined using light microscopy and scanning electron microscopy. Pollen grains of all the studied species were apolar, spheroidal, pantoporate, subtectate with fine reticulation and echinate, but they differed from one another in their size, number of spines and pores, spine length and spine types. The size of grains ranged from 53.3 to 128.7 μm. Cluster analysis was performed based on pollen characters to show the relationship among the species; a key was prepared and is discussed. The observed variation in pollen morphological traits gives important taxonomic information that is useful for distinguishing Ipomoea species and establishing taxonomic and phylogenetic relationships.