Open AccessCytomorphological diversity of Ageratum Species from North-West India.
Author(s) -
Arneet Gill,
Puja Garg
Publication year - 2016
Publication title -
annals of plant sciences
Language(s) - English
Resource type - Journals
ISSN - 2287-688X
DOI - 10.21746/aps.2016.03.002
Subject(s) - ageratum conyzoides , biology , asteraceae , botany , tribe , ploidy , genus , meiosis , chromosome number , floristics , chromosome , karyotype , weed , genetics , gene , sociology , anthropology , taxon
Ageratum belongs to tribe Eupatoriae of family Asteraceae. In the present study floristic forays revealed the prevalence of two species of the genus in North India namely, A. conyzoides and A. houstonianum. Two morphovariants were observed in both the species. The plants were found to differ on the basis of leaf shape and flower colour. Further, analysis of male meiosis revealed the presence of three cytotypes of A. conyzoides and two cytotypes of A. houstonianum. The specimens of A. conyzoides with purple flowers were found to have chromosome count of n=10 (diploid cytotype, 2x) and rarely plants with chromosome count of 2n=30 (triploid cytotype, 3x) were also observed. This is the first report of 3x plants of A. conyzoides from wild. The white flowered plants were found to be tetraploid with n=20. In the specimens of A. houstonianum, the diploid number n=10 was found in white flowered plants while tetraploid number n=20 was found in purple flowered plants. The meiotic course varies from normal to abnormal in some populations of both the species.