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 Larix olgensis 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.
Hypolepis punctata, an aromatic fern with insect-resistant and ornamental potential. Up to date, no studies have reported its micropropagation, particularly using vegetative organs as explants. The optimized stolon sterilization (81.11%) employed 75% ethanol (30 s) and 15% sodium hypochlorite (12 min). The optimal conditions for GGB induction (75.56%) and proliferation (8.46 mm) were achieved using Murashige and Skoog (MS) medium + 2.0 mg/L 6-benzylaminopurine (BA) + 0.2 mg/L 1-naphthaleneacetic acid (NAA). The optimal plant growth regulator (PGR) formula for sporophyte regeneration was 0.5 mg/L BA + 0.1 mg/L NAA + 2 g/L activated charcoal (AC), achieving a 98.89% induction rate and 49.19 buds per explant. The 1/4 MS medium had the greatest promoting effect on biomass accumulation and leaf expansion. Optimal shoot elongation (97.78% success, 4.83 cm) was achieved in 1/4 MS + 0.5 mg/L BA + 0.1 mg/L NAA + 2 g/L AC, and optimized rooting (92.22%) was achieved using 1/4 MS + 0.5 mg/L indole-3-butyric acid (IBA) + 0.1 mg/L NAA + 2 g/L AC, producing 25.27 roots per plantlet. Crucially, ISSR analysis confirmed the genetic stability of all regenerants. This optimized protocol establishes a scalable micropropagation system, enhancing both commercial cultivation and genetic improvement potential in Hypolepis punctata.