A Study on the Cytology and Life-history of <i>Cladophora uberrima</i> Lambert. from Ranchi, India

Abstract

1. The present paper deals with the studies of life-history based upon the cytological features on a fresh-water species of Cladophora viz. C. uberrima Lam-bert, collected from Ranchi in the month of July 1970.2. Stages of mitosis as well as of meiosis follow a normal course.3. A count of 12 mitotic and 6 meiotic chromosomes has been determined for this species. The meiotic chromosomal count (n=6) determined in this species is the first record from India.4. The chromosomes show median and sub-median centromeres like most higher plants. The number of chiasmata in the bivalents ranges from two to four.5. Meiosis precedes quadriflagellate zoospore formation. Formation of gametes has not been observed, however, it is suspected that they are formed preceding mitotic divisions. Thus, the present alga possesses isomorphic alternation of generations, as other species of Cladophora reported by Schussnig (1930), Foyn (1929 and 1934) and Sinha (1963 and 1965).6. Geitler (1936) holds that the basic chromosome number in Order Clado-phorales is 6 and this number has actually been determined in the present species of Cladophora, lending support to Geitler's (1936) view.7. Iron-alum acetocarmine method has been used through out the course of this investigation.The authors are grateful to the authorities of University Grants' Commission, New Delhi for financing the scheme.