The Effect of Plant Growth Regulators and Different Explants on the Response of Tissue Culture and Cell Suspension Cultures of German Chamomile (Matricaria chamomilla L.)
German chamomile (Matricaria chamomilla L.) is one of the most important medicinal plants that its essential oils used in different medicinal industries. In this study which was carried out in 2013 growing season at the Faculty of Agricultural Sciences of the University of Mohaghegh Ardabili, the in vitro response of leaf and hypocotyl explants of German Chamomile in B5 medium supplemented with different levels of plant growth regulators including 2,4-D, naphthalene acetic acid (NAA), kinetin and 6-benzylaminopurine (BAP) were investigated in a factorial experiment based on completely randomized design (CRD).In addition, cell suspension cultures were established and characterized. Hypocotyl and leaf explants exhibited cell proliferation and produced callus within 1-2 weeks. The highest fresh weight of the callus (264.1 mg) was produced by leaf explants in the medium supplemented with 0.5 mg/l 2,4-D and 1 mg/l BAP. However, the leaf explants cultured on medium containing 1.5 mg/l 2,4-D showed the lowest cell proliferation and callus yield (40.42 mg). The highest percentage of root induction from leaf explants (58.73%) was observed on the medium containing 4 mg/l 2,4-D and 1 mg/l Kin, and from hypocotyl explants (48.61%) was observed on medium supplemented with 1.5 mg/l NAA. The 42.22% of calli derived from hypocotyl explants on B5 medium supplemented with 4 mg/l NAA and 3 mg/l BAP, were friable. Cell suspension cultures of German chamomile were established by transferring of hypocotyl-derived friable calli into the MS medium supplemented with 1.5 mg/l 2,4-D and 1 mg/l kinetin. The growth curve of cell proliferations started 4 days after culture and continued to grow until day 13th, where the cells entered stationary phase