Behavior of NOR-Bearing Telosomes in Japanese Garden Iris (Iris ensata Thunb.)

抄録

The behavior of NOR-bearing telosomes in the telotrisomic and its telocentric progenies of Iris ensata was examined by a silver-staining method. In the cross of the telotrisomic “Telotri-1” × the diploid cultivar “Shishinden”, the female transmission rate of a telosome was 15. 6%. All the telotrisomics except one (Telotri-1-1) had 4 NOR-bearing chromosomes and a telosome with 2 Ag-NOR bands which were observed in the maternal plant “Telotri-1”, and a telosome with 2 Ag-NOR bands in the monotelodisomic “Monotelodi-1” was also transmitted from the maternal one. On the contrary, the telotrisomic “Telotri-1-1” had 5 NOR-bearing chromosomes and a telosome with 1 Ag-NOR band. The appearance of this telosome provided the conclusive proof that a simple translocation of 1 Ag-NOR band of the telosome with 2 Ag-NOR ones to a non NOR-bearing chromosome took place in “Telotri-1”. Such a structural change of the telosome was recognized in 9.1% of the telocentric progenies of “Telotri-1”.