title: Heterochromatin distribution and comparative karyo-morphological studies in Vignaumbellata Thunberg, 1969 and V.aconitifolia Jacquin, 1969 (Fabaceae) accessions.
abstract: Chromosome studies along with heterochromatin distribution pattern analysis have been carried out in two domesticated species of Vigna Savi, 1824 which grow in contrasting geo-climatic conditions of India: Vignaumbellata Thunberg, 1969, a legume well acclimatized to subtropical hilly regions of North-east India and Vignaaconitifolia Jacquin, 1969, a species of arid and semi-arid regions in desert plains of Western India. Karyo-morphological studies in both species reveal 2n = 22 chromosomes without any evidence of numerical variation and the overall karyotype symmetry in chromosome morphology suggest that the diversification at intraspecific level in genus Vigna has occurred through structural alteration of chromosomes, rather than numerical changes. Heterochromatin distribution as revealed by fluorochrome binding pattern using CMA3 and DAPI, confirms the occurrence of relatively more GC content in Vignaaconitifolia as compared to Vignaumbellata. However, AT content was found to be comparatively higher in Vignaumbellata which perhaps play a role in species interrelationships.
authors.affiliation: Department of Biotechnology and Bioinformatics, North Eastern Hill University, Shillong-793022, India.
authors.forename: Anju
authors.initials: A
authors.lastname: Shamurailatpam
authors.affiliation: National Bureau of Plant Genetic Resources, Regional Station, Vellanikkara, Thrissur-680654, India.
authors.forename: Latha
authors.initials: L
authors.lastname: Madhavan
authors.affiliation: Department of Botany, Shivaji University, Kolhapur-416004, India.
authors.forename: Shrirang Ramachandra
authors.initials: SR
authors.lastname: Yadav
authors.affiliation: National Research Centre on DNA Fingerprinting, National Bureau of Plant Genetic Resources, Pusa, New Delhi-110012, India.
authors.forename: Kangila Venkatraman
authors.initials: KV
authors.lastname: Bhat
authors.affiliation: Department of Biotechnology and Bioinformatics, North Eastern Hill University, Shillong-793022, India.
authors.forename: Satyawada Rama
authors.initials: SR
authors.lastname: Rao
keywords: Asymmetry index; C-heterochromatin; Fabaceae; NOR-chromosomes; Vigna; karyotype