In vitro culture of Bouvardia ternifolia
Callus cultures were induced from radicle and leaf tissues of Bouvardia ternifolia (trompetilla). Optimum growth regulator concentrations for radicle callus cultures were 1 mg/L 2,4-dichlorophenoxyacetic acid and 0.005 mg/L kinetin; for leaf callus they were either 2 mg/L naphthaleneacetic acid and 0.002 mg/L benzylaminopurine or 5 mg/L of idoleacetic acid and 0.01 mg/L kinetin. Callus has been maintained in culture for nearly 3 years with a very rapid growth rate.A generation time of approximately 24 to 28 h was obtained for batch cell suspension cultures. Production of protoplasts from suspension cultures was optimized with a yield of 70 to 90%. Protoplast culture was achieved in droplets of fresh medium with 2 mg/L napthaleneacetic acid, 0.01 mg/L benzylaminopurine, and0.5 M mannitol. After 2 years, callus in culture still retained its organogenetic capacity. An average of 18 complete plantlets from approximately 2 g of callus can be obtained after transfer to medium with 0.1 mg/L indoleacetic acid and 0.1 mg/L benzylaminopurine.