OBJECTIVE: To evaluate the effect of different phytohormones on callus induction, subculture cycle, and regeneration studies of callus in C. borivilianum.
MATERIALS AND METHODS: Young shoot buds of C. borivilianum were inoculated on Murashige and Skoog medium fortified with 3% sucrose and different concentrations (0, 1, 5, 10, and 15 mg/L) of either naphthalene acetic acid or 2,4-dichlorophenoxyacetic acid or indole-3-acetic acid and callus induction was evaluated up to four subcultures cycles. Shoot regeneration from callus was studied on Murashige and Skoog media fortified with 6-benzylaminopurine andkinetin or thidiazuron at varied levels (0, 0.5, 1, 2, and 3 mg/L). Microshoots were rooted on Murashige and Skoog media supplemented with 1.0 mg/L indole-3-butyric acid and plantlets were acclimatized before transferred to the natural conditions.
RESULTS: Callus induction was better evidenced on Murashige and Skoog media containing 5 mg/L 2,4-dichlorophenoxyacetic acid up to fourth subculture. Callus differentiated into shoots on Murashige and Skoog media fortified with 6-benzylaminopurine or kinetin, whereas thidiazuron completely failed to regenerate shoots. Furthermore, microshoots rooted on 1.0 mg/L indole-3-butyric acid containing Murashige and Skoog media. The rooted plantlets were successfully acclimatized and established in soil with 88.3% survivability.
CONCLUSION: The type of auxins played an important role in inducing callus tissue from shoot bud explants of Safed musli. In future, this in vitro protocol could benefit in crop improvement programs and serve as a new source of bioactive compounds from Safed musli callus tissue for various therapeutic applications.
SUMMARY: Explants de-differentiated to form callus on Murashige and Skoog media containing 5 mg/L 2,4-D up to fourth subculture.Callus re-differentiated into shoots on Murashige and Skoog media fortified with 0.5 mg/L BAP.In vitro rooting of shoots was achieved on 1.0 mg/L IBA containing Murashige and Skoog media.The rooted plantlets were successfully acclimatized and established in soil with 88.3% survivability. Abbreviations used: MS: Murashige and Skoog, NAA: naphthalene acetic acid, 2,4-D: 2,4-dichlorophenoxyacetic acid, IAA: indole-3-acetic acid, BAP: 6-benzylaminopurine, Kn: Kinetin, TDZ: thidiazuron, IBA: indole-3-butyric acid, RCBD: Randomized Complete Block Design, DMRT: Duncan's Multiple Range Test.
RESULTS: Higher calcium concentrations (1.5 and 2% w/v) increased calcium concentration in the peel and pulp tissues, maintained firmness, and reduced anthracnose incidence and severity. While leakage of calcium-treated fruit was lower for 1.5 and 2% calcium treatments compared to the control, microscopic results confirmed that pulp cell wall thickness was higher after 6 days in storage, for the 2% calcium treatment compared to the control. Calcium-treated fruit also had higher total antioxidant activity and total phenolic compounds during storage.
CONCLUSION: Calcium chloride, especially at higher concentrations, is effective in maintaining papaya fruit quality during ambient storage. © 2015 Society of Chemical Industry.