The effect of meta-Topolin (mT) was assessed to develop a reliable protocol for efficient plant regeneration of safflower (Carthamus tinctorius L.) cv. NARI-H-15. For micropropagation, 7 - 9 days old shoot-tip explant...The effect of meta-Topolin (mT) was assessed to develop a reliable protocol for efficient plant regeneration of safflower (Carthamus tinctorius L.) cv. NARI-H-15. For micropropagation, 7 - 9 days old shoot-tip explants cultured on MS basal medium supplemented with 3.0 mg/L meta-Topolin (mT) + 0.5 mg/L CPPU showed 97.7% adventitious shoot formation (42.4 shootlets) than node after 45 days of culture. For organogenesis, the seedling explants of immature leaf cultured on 1.5 mg/L CPPU or 1.5 mg/L NAA fortified medium produced high amount of callus than cotyledon and stem calli after 60 days of culture. However, MS basal medium fortified with 4.0 mg/L mT + 1.5 mg/L CPPU was found beneficial to stimulate 100% organogenic response (74.7 shootlets) from immature leaf calli than cotyledon and stem derived calli after 45 days of culture. The healthy plantlets obtained from micropropagation and organogenesis process cultured on 1/4 MS basal salts, 1.5% sucrose (w/v) and 0.8% agar (w/v) medium supplemented with NAA (1.5 mg/L) and mT (0.1 mg/L) produced maximum of 96% (12.8 rootlets) and 84% (7.3 rootlets) adventitious rooting, respectively than mT and CPPU tested medium. However, maximum of 67% and 42% survival rate was noticed when in vitro raised plants from micropropagation and organogenesis were hardened in pots containing soil mix and maintained under green house condition. This optimized regeneration protocol might be helpful in regeneration of new genotypes and cultivars of safflower to improve agronomic traits through in vitro selection process and Agrobacterium-mediated genetic transformation system.展开更多
Micropropagation protocols to minimize hyperhydricity were optimized for medicinal Scutellaria barbata and Scutellaria racemosa. Six cytokinins and eight different carbon sources at two different incubation periods of...Micropropagation protocols to minimize hyperhydricity were optimized for medicinal Scutellaria barbata and Scutellaria racemosa. Six cytokinins and eight different carbon sources at two different incubation periods of 14 and 21 days were studied for adventitious shoot bud induction using nodal explants. In S. barbata, 5 μM meta-Topolin and 0.1 μM NAA supplemented shoot induction medium produced four shoots each after 14 and 21 day incubation. Observation of S. racemosa nodal explants recorded four and five shoots after 14 and 21 day incubation. In both species, control explants (no plant growth regulators in the medium) consistently resulted in the bud break with two shoots in both 14 and 21 day incubation. The effect of carbon source on shoot regeneration was studied by supplementing eight different sugars at 0.1 M concentration to the optimized shoot induction medium (5 μM meta-Topolin and 0.1 μM NAA). S. barbata nodal explants cultured on shoot induction medium supplemented with fructose and glucose for 14 days produced 10 and nine adventitious shoots respectively;and after 21 day incubation adventitious shoot count reached 19 in glucose supplemented medium. S. racemosa explants in the same experiment produced five shoots in maltose and four shoots in sorbitol supplemented medium after 14 day incubation;whereas after 21 day incubation, sucrose and maltose produced five shoots;fructose, glucose, and sorbitol produced four shoots. Regenerated plants were successfully acclimatized and Scanning Electron Microscopy of the leaf surface revealed differences in stomatal behavior and cuticle deposition between in vitro and acclimatized plants. The antioxidant assay conducted on both Scutellaria species showed considerable total polyphenol content, TEAC activity and flavonoid content in fresh and dried leaf samples attributing to their medicinal potential.展开更多
文摘The effect of meta-Topolin (mT) was assessed to develop a reliable protocol for efficient plant regeneration of safflower (Carthamus tinctorius L.) cv. NARI-H-15. For micropropagation, 7 - 9 days old shoot-tip explants cultured on MS basal medium supplemented with 3.0 mg/L meta-Topolin (mT) + 0.5 mg/L CPPU showed 97.7% adventitious shoot formation (42.4 shootlets) than node after 45 days of culture. For organogenesis, the seedling explants of immature leaf cultured on 1.5 mg/L CPPU or 1.5 mg/L NAA fortified medium produced high amount of callus than cotyledon and stem calli after 60 days of culture. However, MS basal medium fortified with 4.0 mg/L mT + 1.5 mg/L CPPU was found beneficial to stimulate 100% organogenic response (74.7 shootlets) from immature leaf calli than cotyledon and stem derived calli after 45 days of culture. The healthy plantlets obtained from micropropagation and organogenesis process cultured on 1/4 MS basal salts, 1.5% sucrose (w/v) and 0.8% agar (w/v) medium supplemented with NAA (1.5 mg/L) and mT (0.1 mg/L) produced maximum of 96% (12.8 rootlets) and 84% (7.3 rootlets) adventitious rooting, respectively than mT and CPPU tested medium. However, maximum of 67% and 42% survival rate was noticed when in vitro raised plants from micropropagation and organogenesis were hardened in pots containing soil mix and maintained under green house condition. This optimized regeneration protocol might be helpful in regeneration of new genotypes and cultivars of safflower to improve agronomic traits through in vitro selection process and Agrobacterium-mediated genetic transformation system.
文摘Micropropagation protocols to minimize hyperhydricity were optimized for medicinal Scutellaria barbata and Scutellaria racemosa. Six cytokinins and eight different carbon sources at two different incubation periods of 14 and 21 days were studied for adventitious shoot bud induction using nodal explants. In S. barbata, 5 μM meta-Topolin and 0.1 μM NAA supplemented shoot induction medium produced four shoots each after 14 and 21 day incubation. Observation of S. racemosa nodal explants recorded four and five shoots after 14 and 21 day incubation. In both species, control explants (no plant growth regulators in the medium) consistently resulted in the bud break with two shoots in both 14 and 21 day incubation. The effect of carbon source on shoot regeneration was studied by supplementing eight different sugars at 0.1 M concentration to the optimized shoot induction medium (5 μM meta-Topolin and 0.1 μM NAA). S. barbata nodal explants cultured on shoot induction medium supplemented with fructose and glucose for 14 days produced 10 and nine adventitious shoots respectively;and after 21 day incubation adventitious shoot count reached 19 in glucose supplemented medium. S. racemosa explants in the same experiment produced five shoots in maltose and four shoots in sorbitol supplemented medium after 14 day incubation;whereas after 21 day incubation, sucrose and maltose produced five shoots;fructose, glucose, and sorbitol produced four shoots. Regenerated plants were successfully acclimatized and Scanning Electron Microscopy of the leaf surface revealed differences in stomatal behavior and cuticle deposition between in vitro and acclimatized plants. The antioxidant assay conducted on both Scutellaria species showed considerable total polyphenol content, TEAC activity and flavonoid content in fresh and dried leaf samples attributing to their medicinal potential.
