An Uncommon Plant Growth Regulator, Diethyl Aminoethyl Hexanoate, Is Highly Effective in Tissue Cultures of the Important Medicinal Plant Purple Coneflower (Echinacea purpurea L.)

Table 4

Effects of different concentrations of DA-6 on the growth of hexaploid buds*.

Concentration of DA-6 (mg/L)	Plant height (mm)	Weight per plant (mg)	Root weight per plant (mg)	Diameter of; thickest root (μm)	Total root no.	Length of primary root (mm)	Total root length (mm)	Root/top ratio
0	15.60 ± 1.71^ab**	212.70 ± 17.38^ab	63.20 ± 12.47^b	1420.00 ± 62.91^d	2.30 ± 0.37^ab	27.88 ± 3.02^bc	30.30 ± 4.67^ab	42.93 ± 8.13^b
0.08	20.40 ± 3.28^a	279.40 ± 42.81^a	116.60 ± 65.02^a	1650.09 ± 98.80^c	3.70 ± 1.09^a	44.77 ± 5.12^a	56.00 ± 11.65^a	75.15 ± 10.26^a
0.16	14.10 ± 2.69^ab	170.70 ± 30.17^b	53.40 ± 15.43^b	2495.55 ± 81.22^a	2.20 ± 1.02^ab	36.25 ± 8.50^ab	36.70 ± 12.13^ab	54.52 ± 10.70^ab
0.32	11.20 ± 1.91^b	143.90 ± 25.62^b	39.40 ± 11.01^b	2180.24 ± 66.53^b	0.90 ± 0.18^b	17.75 ± 2.54^c	14.40 ± 3.81^b	36.18 ± 8.36^b

∗Values of plant height, weight per plant, root weight per plant, diameter of thickest root, total root no., length of primary root, total root length, and root/top ratio are expressed as the mean ± SD.
∗∗Data in the same column followed by different letters are significantly different by Duncan’s test at P < 0.05.