Chitosan versus plant growth regulators: a comparative analysis of their effects on in vitro development of Serapias vomeracea (Burm.f.) Briq

• Published in: Plant cell, tissue and organ culture tissue and organ culture, 2020-05, Vol.141 (2), p.327-338
• Main Author: Acemi, Arda
• Format: Article
• Language: English
• Subjects: Acetic acid; Acids; Auxins; Benzyladenine; Biomedical and Life Sciences; Browning; Butyric acid; Chitosan; Comparative analysis; Cytokinins; Degree of polymerization; Elongation; Germination; Growth regulators; Indole-3-butyric acid; Indoleacetic acid; Jasmonic acid; Kinetin; Life Sciences; Oligomers; Original Article; Plant Genetics and Genomics; Plant growth; Plant Pathology; Plant Physiology; Plant Sciences; Polymerization; Polymers; Rooting; Seed germination
• ISSN: 0167-6857; 1573-5044
• DOI: 10.1007/s11240-020-01789-3

This study aimed to compare the in vitro effects of chitosan oligomers and polymer with commonly-used plant growth regulators (PGRs) on seed germination, protocorm formation, and organ development in Serapias vomeracea . The effects of N -acetylated (10%) chitosan oligomer mixture (CHI-OM) with a degree of polymerization (DP) between 2 and 15 (5, 10, 15, and 20 mg L −1 ) and chitosan polymer (CHI-P) with a DP of 70 were compared with commonly-used cytokinins [6-benzylaminopurine (BAP) and kinetin (KIN)], auxins [indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA)], and jasmonic acid (JAS) at 0.25, 0.5, 1.0, and 2.0 mg L −1 . The medium supplemented with CHI-P at 5 mg L −1 gave the highest seed germination rate, whereas JAS and CHI-OM triggered protocorm formation better than the all treatments tested. The JAS and IAA treatments resulted in intense browning of the roots. The CHI-P treatments at high concentrations and JAS treatments at moderate concentrations increased mean shoot length while the medium containing KIN at 0.5 mg L −1 induced root elongation significantly. The root elongation-inhibitory effect of chitosan was observed at the higher concentrations of CHI-OM, but the media containing 10 mg L −1 CHI-OM and 15 mg L −1 CHI-P triggered adventitious rooting. However, the highest tuberization success was found after 10 mg L −1 CHI-OM and 0.5 mg L −1 JAS treatments. Tuber development was achieved in the media supplemented with BAP and CHI-OM. This study suggested that well-characterized chitosan could be used as an alternative to JAS and BAP in orchid cultures. Key message Well-characterized chitosans at the right concentration induce similar effects with jasmonic acid and 6-benzylaminopurine in orchid cultures.