Induction of Tetraploids from Petiole Explants through Colchicine Treatments in Echinacea purpurea L.

Table 4

Comparison of the effect of colchicine treatment duration on chromosome doubling of regenerated plants.

Treatment duration (days)	No. plants sampled	No. root tip sampled	No. cells observed	No. cells with 2x chromosomes	No. cells with 4x chromosomes	No. each kind of plants on the base of chromosome counting*
						2x plants	4x plants	Chimera
7	51	88	3915	3903	12	45	0	6 (12/902/14)
14	51	89	3746	3463	283	37	6 (248/248/10)	8 (35/762/13)
21	51	88	3237	2823	414	35	10 (391/391/15)	6 (23/371/10)
28	51	87	3350	2781	569	35	12 (546/546/20)	4 (23/311/8)

*Data in the parenthesis are no. of 4x cells/ no. of cells observed/No. of root tips sampled.