Karyotype analysis of Egyptian henbane, Hyoscyamus muticus L

Mitotic chromosomes from root tips of an inbred CIMAP/MP-41 of H. muticus were analyzed cytologically. The fourteen pairs of chromosomes were numbered from 1 to 14 on the basis of their descending order of length. The average length of metaphase chromosomes was 2.85μ, varying from 2.14μ to 3.88μ. There was only one pair of satellite-chromosomes, the nucleolus being organized by short arm. The arm ratio ratio ranged from 0.26 to 0.91. The six choromosomes had nearly median centromere and the remaining eight had nearly sub-median centromere. All the fourteen chromosomes could be identified on the basis of their total length and arm ratio when arranged in a specific manner. However, there remained a considerable risk of reversal-of-order error.