Karyotypic studies in the genus Cyamopsis 1. C. tetragonoloba

Abstract EN

fhis study was carried out on the chromosome complement of ten lines of guar (Cyamopsis tetragonoloba), using the C-banding technique.

The chromosome number 2n = 2x = 14, and the mean chromosome length ranged between 1.40 ٣٦٦ and 4-13 ٣١٦٦.

with an overall mean of 2.78 ٣m.A great variation in length in chromosome 1 was observed, among the ten lines, with a range of 3.69 ٣٦١ - 4.5 1 ٣١٦٦.

Similar variation was observed for chromosome 2; its length ranged between 3.88 ٣٢١ and 4.27 ٣٦٦ .

The mean length of the haploid genome was 19.07 ٣١١-19.73 ٣٦٦, W'ith a mean of 19.46 ٣١٦٦.

No B-chromosomes were detected.

Chromosome lwas submetacentric with ١١٦؛ arm ratio of 2.05.

'fhe mean arm ratio for chromosomes 2,3,4,5,6 and 7 ranged between 1.10 and 1.63 and were all metacentric.

Hence, the karyotype formula is 6m+lsm.

The total formula of chromosomes was 42.21%, and the intrachromosomal index was 0.23.

The symmetry index was 33.0% and relative length was 7.0% - 20.ل%.

A secondary constriction was detected on the long ٧١١٦٦ of the homologous pair of ehromosomel.C-banded regions were found on