Abstract
Karyotype ofEupatorium adenophorum (2n = 51),Eupatorium riparium (2n = 51) andEupatorium odoratum (2n = 60) has been studied. Their T.F. values are 46 · 14%, 49 · 14% and 46 · 40% whereas the complement length is 64 · 61 µ, 51 · 59 µ and 89·82 µ respectively. Based on x = 10 and 17 and meiotic behaviour, the first two species have been suggested to be autotriploids and the third as allohexaploid. These species were introduced into India from America and became successful colonizers and weeds. Polyploidy, agamospermy, vegetative reproduction and genie heterozygosity confer an advantage in competition.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Auld B A 1964 The distribution ofEupatorium adenophorum Spreng. on the far north coast of New South Wales;J. Proc. R. Soc. New South Wales 102 159–161
Avdulov N P 1931 Karyo-Systematische Untersuchungen der Familie Gramineen;Bull. Appl. Bot. Suppl. 44 1–428
Baker H G 1965 Characteristics and Modes of Origins of Weeds; inGenetics of colonizing species, eds H G Baker and G L Stebbins (New York: Academic Press)
Coleman J R 1968 Chromosome numbers in some Brazilian Compositae;Rhodora 70 228–240
Dobzhansky Th, Ayala F G, Stebbins G L and Valentine J W 1977Evolution (San Francisco W H Freeman and Company)
Ghosh R B 1961 Chromosome number of some flowering plants;Curr. Sci. 30 73
Grant W F 1953 A Cytotaxonomic study in the genusEupatorium;Am. J. Bot. 40 729–742
Huziwara Y 1955 Karyotype analysis in some Genera ofCompositae I Karyotype of JapaneseEupatorium;Cytologia 21 114–123
Keil D J and Pinkava D J 1976 Chromosome counts and Taxonomic notes for Compositae;Am. J. Bot. 63 1393–1403
Keil D J and Stuessy T F 1977 Chromosome counts of Compositae;Am. J. Bot. 64 791–798
King R M, Kyhos D W, Powel A M, Raven P H and Robinson H 1976 Chromosome number of Compositae XIIIEupatorieae;Ann. Missouri. Bot. Gard. 63 862–888
Mehra P N, Gill B S, Mehta J K and Sidhu S S 1965 Cytological investigations on the Indian Compositae I North Indian Taxa;Caryologia 18 35–68
Mehra P N and Ramanandan P 1975 Cytological investigations of Indian Compositae IV Tribes Senecionsae, Eupatorieae, Vernonieae and Inuleae;Nucleus 18 6–19
Mehra P N 1977 Cytological investigations on the Indian Compositae;Cytologia 42 347–356
Montgomery J B and Fair brothers D E 1970 A biosystematic study of theEupatorium rotundi- folium complex (Compositae);Brittonia 22 134–150
Oloredo O 1974 Chromosome numbers in Nigerian Compositae;Bot. J. Linn. Soc. 68 329–335
Powell A M, Kyhos D W and Raven P H 1975 Chromosome numbers in compositae XI Helenieae;Am. J. Bot. 62 1100–1103
Stebbins G L 1950Variation and Evolution in plants (Calcutta: Oxford Book Company)
Stebbins G L 1958 Longevity, Habitat and release of Genetic Variability in the higher plants;Cold Spring Harbor Symp. Quant. Biol. 23 365–378
Subramanyam K and Kamble N P 1971 In A Love (ed.) IOBP Chromosome number Reports XXXI;Taxon 20 160
Sullivan V I 1976 Diploidy, polyploidy and agamospermy among species ofEupatorium (Compositae);Can. J. Bot. 54 2907–2917
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Khonglam, A., Singh, A. Cytogenetic studies on the weed species ofEupatorium found in Meghalaya, India. Proc. Indian Acad. Sci. 89, 237–241 (1980). https://doi.org/10.1007/BF03046162
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF03046162