Characterization of essential oil distribution in the root cross-section of Valeriana officinalis L. s.l. by using histological imaging techniques

Table 1 Root morphology types and content of essential oil in the root drug of the cloned elite plants (CE)

Cloned elites	Varieties	Morphological root structure	Essential oil^a	Root fraction (diameter)
Cloned elites	Varieties	Classification	ml kg⁻¹	RF1 (< 2 mm)^b	RF2 (< 3 mm)^b	RF3 (< 4 mm)^b	RF4 (> 4 mm)^b
CE1	‘Anton’	Thin-rooted	8.9 (14.1)	●	●	●	—
CE2	‘Anton’	Thin-rooted	10.4 (19.9)	●	●	●
CE3	‘Anton’	Thick-rooted	5.0 (12.9)	●	●	●	●
CE4	‘Lubelski’	Thick-rooted	6.9 (11.3)	●	●	●	●

Prevalence of root thickness fractions (RF) in the clone plants
^aEssential oil content of the mother plant (elites) and in brackets the cloned elites, determined in 2010 and 2012, respectively
^bDiameter at the base (Horizon 1, see Fig. 1) is decisive for the classification to a fraction. The ● indicates the formed and the — indicates the not formed fractions

ISSN: 1746-4811