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

Table 2

Comparison of the effect of colchicine concentration on chromosome doubling of regenerated plants.

Colchicine concentration (mg/L)	No. plants sampled	No. root tips sampled	No. cells observed	No. cells with 2x chromosome	No. cells with 4x chromosome	No. each kind of plants on the base of chromosome counting*
						2x plants	4x plants	Chimeras
30	51	89	3653	3642	11	45	0	6 (11/429/9)
60	51	86	3690	3515	175	42	3 (154/154/6)	6 (21/653/11)
120	51	83	3542	3132	410	37	11 (389/389/19)	4 (21/360/7)
240	51	90	3418	3251	167	45	4 (154/154/7)	2 (13/114/4)

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