High frequency regeneration of plants via callus-mediated organogenesis from cotyledon and hypocotyl cultures in a multipurpose tropical tree (Neolamarkia Cadamba)

Abstract

In this works, a simple, efficient and repeatable protocol was developed for in vitro regeneration via callus-mediated organogenesis of Neolamarkia Cadamba using cotyledonary petioles and hypocotyls. Effects of basal medium, plant growth regulators, the types and age of explant on the formation of adventitious buds/shoots were studied. Meanwhile, histological analysis for early ontogenic stages and genetic stability assessment by flow cytometry were investigated. Our investigation demonstrated that, compared with 6-benzyladenine (BA), N 6-(2-isopentenyl) adenine (2-ip), Thidiazuron (TDZ) was the optimal cytokinin for buds/shoots induction on cotyledon and hypocotyl explants. Douglas-fir and sugar pine medium (DCR) supplemented with 22.7 μM TDZ and 0.27 μM α-naphthalene acetic acid (NAA) was most effective on bud induction, with the highest bud-induction rate and numbers of buds on cotyledon and hypocotyl explants. The available shoot per explant hit 35.2 when the induced callus sub-cultured to a medium without TDZ. It was found that TDZ could promote induction of the callus and the buds, however, continuous exposure beyond 4 weeks of supplemented high concentration (exceed 11.35 μM), TDZ was harmful to the proliferation and growth of buds/shoots. DCR appeared more efficiency than Murashige and Skoog medium (MS), Woody Plant medium (WPM), anther culture of cereal crops medium (n 6) on bud induction. Age of cotyledon and hypocotyl explants in 20-day to 25day was most beneficial to adventitious buds/shoots formation. Histological investigation confirmed that the buds originated from the wounded incisions of cotyledonary petiole and hypocotyl fragments, with callus formation. The regeneration plantlets were successfully acclimatized in greenhouse, yielded above 95% survival rate in field, exhibited normal morphology and growth characteristics. The analysis of flow cytometry on N. cadamba indicated no variation in the ploidy levels between the regenerated plantlets and the donor trees. The developed procedure can be used for mass production, germplasm exchange and transgenic studies to improve the resistance of the species via Agrobacterium-mediated. Neolamarckia cadamba (commonly known as burflower tree, kadamba tree or kadamb) is a tropical tree of great economic importance. First, N. cadamba trees grow fast, and their wood is good for pulp production, furniture, and other construction purposes 1. Second, N. cadamba has been traditionally used as medicine to treat diseases such as dysentery, fever and snake bites 2,3. Now, from its bark, leaves, and flowers people extract phytochemical compounds, including monoterpenoid, triterpenoid saponin, and ethylene glycol 4-9 , alkaloid 10 , cadambine 7,11 , and use them to treat hyperglycemia 12 , hyperlipidemia 13,14 , hypertension 15 , and wound and skin diseases 16. Third,

Organogenesis from Leaf-derived Calli of S. potatorum L. f.: A Vulnerable Medicinal Tree Species

“…NAA is the best auxins showed effective rhizogenesis. The similar findings of high root induction were reported in Neolamarkia cadamba 21 , Coccoloba uvifera 22 . This may be due to an appropriate concentration of auxin acting on cells, which is beneficial for binding with ATP enzyme on the plasma membrane.…”

In vitro daylily (Hemerocallis species) bract multiple shoot induction

“…This establishes the bract as a reliable explant for daylily in vitro propagation. The application of TDZ in previous tissue culture studies has often resulted in very effective responses across plant species and superior performances over different other growth regulators (Huang et al, 2020;Chen et al, 2020). Because of the differential level of difficulty to micro-propagate plant species, there is an exhaustive effort to explore a spectrum of plant tissues, including the bract, for their totipotency potential.…”

Cytokinin-Based Tissue Cultures for Stable Medicinal Plant Production: Regeneration and Phytochemical Profiling of Salvia bulleyana Shoots

“…Several reports suggest that TDZ was far more effective in inducing adventitious buds than other cytokinins [26][27][28]. TDZ not only demonstrates cytokinin-like activity by supporting the induction of indirect shoot organogenesis, but also it is effective in callus induction: a characteristic of auxins.…”