High Concentration of Thidiazuron Stimulates Adventitious Bud Regeneration from Cotyledon Explants in Jatropha curcas

摘要

A high-frequency protocol for induction of adventitious buds and plant regeneration from cotyledon explant of Jatropha curcas is described. The cotyledon explants of J. curcas cultured directly onto medium containing Thidiazuron (TDZ) induced regeneration of only poor quality adventitious buds that had a low regeneration frequency, and subsequently the elongation of shoot-buds was difficult and unsatisfactory. However, treating the cotyledon explants with high concentrations (10-60 mg/L) of TDZ solution for short time periods (10-60 min) helped to improve the regeneration frequency and enhance the quality of the regenerated shoot-buds significantly. The best shoot-buds induction (87.45%) and number of shoot-buds (11.23) per explant were seen when in vitro explants were treated with 20 mg/L TDZ solution for 40 min before being inoculated onto hormone-free Murashige and Skoog (MS) medium in 30 days. The elongated shoots initiated roots to become intact plantlets in rooting medium supplemented with 0.1 mg/L indole-3-butyric acid (IBA) effectively stimulated the initiation and growth of roots with the best rooting rate (44.28%). After acclimatization, these plantlets were transplanted to soil wherein normal growth was observed. Hence, an intact plantlet could usually often be gained at 60 to 70 days of culture by applying the culture method described in the present study. This protocol could be widely used for mass production of regenerative plants and the yield of transgenic plants through Agrobacterium-mediated transformation.