TRICHOMES AND PAPPI STRUCTURES AS AID TO THE MICROSCOPIC IDENTIFICATION OF ASTERACEAE OF PANTNAGAR, UTTARAKHAND, INDIA.

The morphological diversity of trichomes and pappi in 20 common Asteraceae members were studied from the standpoint of species identification. Thirteen of these species bear trichomes on all surfaces and 16 types of trichomes were recorded. Non-glandular, multicellular, uniseriate trichomes with long terminal cell are the most common type recorded at 87 observed surfaces of 16 species. Some trichome types were restricted to one or two species. The trichomes of Leucomeris spectabilis are being reported for the first time. The pappi were recorded in 13 species and their morphology is quite characteristic of species and genera. Separate dichotomous keys are constructed to help identify the species on the basis of trichomes and pappi exclusively. [ABSTRACT FROM AUTHOR]