Establishment of Hairy Root Cultures of Rhaponticum carthamoides (Willd.) Iljin for the Production of Biomass and Caffeic Acid Derivatives

Table 1

Induction of hairy roots of R. carthamoides derived from leaf explants by direct infection with Agrobacterium rhizogenes strains A4 and ATCC 15834.

Bacterial strain	Site of infection	Medium	% of explants forming roots	Mean number of roots/explants	Root length (cm)
A4	Petiole	MS	27.8^a	3.0 ± 0.20^a	1.6 ± 0.10^a
		MS + AcS	37.3^b	3.1 ± 0.14^a	1.7 ± 0.08^a
	Lamina	MS	35.0^ab	2.1 ± 0.12^b	1.5 ± 0.10^a
		MS + AcS	43.3^b	2.1 ± 0.09^b	1.6 ± 0.08^a
ATCC 15834	Petiole	MS	17.3^cd	1.7 ± 0.22^bc	1.2 ± 0.13^a
		MS + AcS	22.7^d	1.3 ± 0.11^c	1.2 ± 0.11^a
	Lamina	MS	13.3^c	1.5 ± 0.19^c	1.3 ± 0.11^a
		MS + AcS	18.3^cd	1.3 ± 0.12^c	1.6 ± 0.14^a

Explants were infected with a needle dipped in the bacterial culture and placed on hormone-free MS agar (0.7%) medium without (MS) or with 200 M acetosyringone (MS + AcS). Observations were recorded after 5 weeks. Each treatment involved 25–35 explants. The experiments were repeated three times. Values are given as the mean ± SE (standard error). The experiment means followed by the same superscript letter within the column are not significantly different at the level of ≥ 0.05 (the Mann-Whitney test).