The karyomorphology of seven different cultivated varieties of Capsicum annuum L. was studied to determine similarities and differences amongst the karyotypes and to provide diagnostic features of the different chromosomes in the haploid complement of each variety. Capsicum annuum exhibits certain morphological variations with respect to fruit size, fruit stalk length, number of fruits per plant, number of seeds per fruit, etc. Therefore seven morphologically distinct varieties were used for studies. It was observed that although the somatic chromosome number is the same (2n = 24) in all the seven varieties studied, they differed markedly in their chromosome morphology and total haploid chromatin length. The total length of the haploid complement in the varieties studied varied from 48.26 to 62.96 μm. All the varieties have comparable chromosome size, karyotype symmetry and chromosome types. The number of satellites varied from 1 to 2 and they were present at the end of the short arm. Long arm/short arm ratio was the highest in cultivated variety Pusa sadabahar, showing its advanced nature. The total haploid chromatin length was found to have a significant positive correlation with the pericarp weight, number of seeds/fruit, fruit stalk length, fruit girth and fruit surface area. Thus from the karyotype features, the varieties appear to be distinct. The seven cultivated varieties of Capsicum annuum L. have comparable chromosome size, karyotype symmetry and chromosome types. They exhibit close relationships which indicate their probable origin from a common ancestor. In finer details, some recognizable differences were noticed between the varieties. Thus the karyotype analysis of the seven varieties revealed that minute structural alteration of chromosomes associated with genomic chromatin length, etc, has played an important role in establishment of new cultivated varieties.

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