Giemsa C-banding Pattern in Some Cultivars of Trichosanthes dioica Roxb

Abstract

To assess the role of heterochromatin, if any, in intraspecific diversification, a detailed study of the distribution pattern of Giemsa C-heterochromatin in three gynoecious cultivars of Trichosanthes dioica Roxb., namely, ‘Kali, ‘Kalyani’ and ‘Sanjiban’ has been undertaken.
The somatic chromosomes are characterized by distinct telomeric bands. The differential banding pattern can be conveniently used for distinguishing between the cultivars. The cultivar ‘Sanjiban’ stands apart from the rest in possessing seven chromosomes with one or more intercalary bands in addition to the telomeric bands at both arms. The cultivars ‘Kali’ and ‘Kalyani’, however, can be distinguished from each other by the presence of five chromosomes with two telomeric bands in each in the former while four such chromosomes are represented in the latter.
The application of Giemsa C-banding method reveals a differential distribution of C-heterochromatin in the cultivars investigated thus demonstrating the active involvement of heterochromatin in intraspecific diversification of T. dioica.