Karyomorphological Studies in Chlorophytum Ker-Gawl

Abstract

Chromosome morphology of six Chlorophytum species reveal symmetrical karyotypes in C. laxum (2n=16) and asymmetrical in C. glaucum and C. orchidastrum (2n=42). Remaining three species, viz. C. tuberosum, C. attenuatum (2n=16) and C. comosum (2n=28) appear to be intermediate in the karyotype symmetry. In C. attenuatum and C. orchidastrum two pairs of SAT chromosomes with variations in their sequence numbers and arm ratios have been observed, whereas in rest of the species only one SAT pair could be observed. Tentative basic chromosome number for the genus has been suggested to be x=8 and 7, possibly derived as secondary number from x=4. Role of polyploidy in the speciation process, centre of origin and geographical distribution in relation to karyomorphology have been discussed.