Chromosomal Characterization and First Report of Aneuploidy in Crotalaria spp. from Bangladesh

Abstract

Ten germplasms of Crotalaria species viz. C. pallida, C. incana and C. juncea available in Bangladesh were investigated cytogenetically to find out the chromosomal variation. In C. pallida 2n=16 (Acc. No. 4803, 4805, and 4807) and 2n=18 (Acc. No. 4250 and 4806) chromosomes were observed. In contrast, C. incana was found to possess 2n=16 (Acc. No. 4801), 2n=17 (Acc. No. 4790 and 4804), and 2n=18 (Acc. No. 4809) chromosomes while 2n=16 was observed in C. juncea. Somatic chromosome number 2n=17 in Acc. No. 4790 and 4804 of C. incana might be originated either by intraspecific hybridization between 2n=18 and 2n=16 germplasm or by aneuploid origin that correlates with their phenotypic features like seedless pod formation. This information of these two germplasms can help to the further breeding program. The variation of chromosomal length in all germplasms was almost negligible. Metacentric chromosomes were found in most germplasms indicate their symmetric nature. In contrast, submetacentric chromosomes were observed in several germplasms of C. pallida and C. incana indicates a relatively asymmetric nature. Therefore, each germplasms of Crotalaria could be characterized authentically by cytogenetical analysis.