Efficient organogenesis and taxifolin production system from mature zygotic embryos and needles in larch

Abstract

The deciduous conifer larch has been widely distributed around the world, which is a high-quality wood species and is also used to extract industrial raw materials and medicines. In this study, we developed an organogenesis protocol for <italic>Larix olgensis</italic> from both mature zygotic embryos and needles, and analyzed the content of taxifolin in different tissues. The highest callus induction (96.8%) from mature zygotic embryo was got in the Douglas-fir Cotyledon Revised (DCR) medium augmented with 2.0 mg/L 6-Benzylaminopurine (6-BA) and 0.2 mg/L α-Naphthaleneacetic acid (NAA), while from needles the highest callus induction (92.03%) was got in the Murashige and Skoog (MS) medium augmented with 3 mg/L 6-BA and 0.3 mg/L NAA. The best shoot regeneration capacity from zygotic embryo-derived calli (83.3%) was obtained in DCR medium augmented with 1.0 mg/L 6-BA and 0.01 mg/L NAA, and needle-derived calli were 77.3%. The shoots achieved the highest elongation (75.6%) in the DCR medium supplemented with 0.5 mg/L 6-BA, 0.05 mg/L NAA and 2g/L activated charcoal (AC). The rooting rate was 62.8% in DCR medium augmented with 3 mg/L Indole-3-butyric acid (IBA) and 100 mg/L phloroglucinol (PG). The accumulation of the taxifolin in elongation shoots and lignified elongation shoots have greatly improved along with the development process, were 28.6 µg/g, and 53 µg/g respectively. The content of the taxifolin in callus was 1.99-5.26 µg/g, adventitious shoots were 4.8µg/g, and adventitious roots were 2.86 µg/g. To date, we reported an efficient organogenesis and taxifolin production protocol in larch for the first time.