CYTOPALYNOLOGICAL STUDY ON
VERNONIEAE (ASTERACEAE) FROM SOUTH INDIA
to the tribe Vernonieae of the family
is an erect or decumbent herb to 75 cm
high; stem pubescent and flexible, commonly seen in waste lands and open forests.
Plants were collected from different low and high altitude regions of Tamilnadu and Kerala
Chromosome studies were made from PMCs at meiosis and /or root tips. Flower
buds and root tips were fixed in Carnoy’s fluid and stained in Lactopropionic Orcien. Root
tips were pre-treated with .002 M solution of 8 hydroxyquinoline for 3h. A few drops of
ferric acetate solution were added to the fixative prior to staining, and this was found to
increase the stainability of chromosomes. Photomicrographs of PMCs and root tip cells were
taken using an Olympus BH-2 research microscope.
The pollen preparations were made by acetolysis method
(Erdtman1952; Nair, 1970). Pollen morphological features analysed include pollen aperture,
exine ornamentation, pollen size and shape using LM/SEM .Categorization of pollen shape
and size were done following the classification of Erdtman (1952) and Walker and Doyle
(1975) respectively. For describing the aperture type and exine ornamentation pattern of the
pollen grains, the terminologies suggested by Nair and Lawrence (1985) have been used
3-zono colpate ,aperture circular,lophate, nearly homobrochate.
Exine 4.2µm thick;colpus small,situated at the centre of the apertural lacuna,The
brochi being larger with broad lacuna( diameter) and a narrow muri (breadth)
muri pentangular with a single row of equidistant spinules.
Grain shape : Prolate spheroidal
Grain size : 28 -30.8 µm (Medium)
C.cinereum - Pollengrains