Exogenous Hormones Affecting Morphology and Biosynthetic Potential of Hairy Root Line (LYR2i) of Linum album

Abstract

A hairy root line of Linum album LYR2i was obtained via the genetic transformation of a cotyledon segment of the plant by cocultivating it with Agrobacterium rhizogenes and culturing it in hormone-free B5 Gamborg liquid medium. Characteristic changes in root morphology associated with variations in biosynthetic capabilities were achieved by adding different combinations of phytohormones to the basal medium. A reversible system between hairy roots and its cultures with a diversified morphology was established by including and excluding phytohormones in the basal medium. The medium containing indole 3 acetic acid (IAA) at a concentration of 3 mg/l (MI3) induced thicker root tips and that containing 2,4-dichlorophenoxy acetic acid (2,4-D) at a concentration of 1 mg/l (MD1) induced compact green callus. Podophyllotoxin and 6-methoxypodophyllotoxin content increased by 1.86-fold and 1.45-fold as a result of adding IAA (MI3) and 2,4-D (MD1) to the basal medium, respectively. After regeneration, the hairy roots regained their original morphology and biosynthetic capability on hormone-free basal medium. The transformation status of the regenerated hairy roots was confirmed by PCR analysis.