Effects of variations in culture media and hormonal treatments upon callus induction potential in endosperm explant of Barringtonia racemosa L

Objective: To induce callus from the medicinally valuable species, Barringtonia racemosa L. (B. racemosa) whereby the formation of callus is essential for micropropagation studies and in vitro plant secondary metabolites production. Methods: The callus induction potential in B. racemosa was assessed from endosperm explant cultured on different culture media and plant hormonal treatments. Lloyd and McCown's woody plant medium and Murashige and Skoog's medium were used in the study as culture media. On the other hand, various concentrations and combinations of 2,4-dichlorophenoxyacetic acid (1.0-2.0 mg/L) and kinetin (0.5-2.5 mg/L) had been incorporated in the culture media to exert the effects of auxin and cytokinin on callus induction. Results: From the present study, it was found that the profuse [(1.681 ± 0.770) g fresh weight, (0.239 ± 0.239) g dry weight] and friable callus formation was optimally produced with desirable morphology and considerable percentage of callus induction (56.70%) in endosperm explants cultured on 1.0 mg/L 2,4-dichlorophenoxyacetic acid and 1.5 mg/L kinetin in Murashige and Skoog's medium. Conclusions: A reliable protocol for inducing callus formation of profuse and friable morphology in endosperm explant of B. racemosa had therefore been successfully established.

Micropropagation and Phenolic exudation protocol for Excoecaria agallocha-an important mangrove

Objective: To develop a standard micropropagation protocol for an important vulnerable mangrove Excoecaria agallocha. Methods: Collection of explants, surface sterilization, phenolic exudation and medium was standardized. Shoot induction, shoot multiplication and rooting were carried out in MMS medium supplemented with BAP, Kinetin, Zeatin, 2ip, NAA, IAA and IBA. Hardening was carried out after root well established. Results: The best phenolic exudation removal was resulted in 4 g/L activated charcoal. The maximum shoot induction response showed in MMS medium and better shoot induction was performed in the concentration of BAP (3.9 μmol) and NAA (1.34 μmol). Rooting induction was performed high range at 5.02 μmol of IAA. Well rooted micro-shoots were hardened and acclimatized. Conclusions: From the present investigation, it can be concluded that a standard micropropagation protocol was developed for an important vulnerable mangrove species.

Micro propagation and tissue culture of the endangered medicinal plant withania somnifera by the direct shoot and root initiation method.

Leaf and Cotyledon explants of Withania somnifera (L). Dunal were used to evaluate the effect of different growth regulators on the in vitro direct shoot and root initiation methods. Four different explants were used to establish callus shoot and root direct regeneration. In the first experiment leaf segments were cultured on MS basal supplemented with 2,4 – Dichlorophenoxyacetic acid (2,4 – D, 0.1-20.0 mg/L), with combination of Naphthalene acetic acid (NAA 0.1-20 mg/L) and Benzylaminopurin (0.1-20 mg/L). This new protocol was standardized for easy mass propagation of W. somnifera medicinal plant. Callus initiation was observed best in MS media with (2,4- D 1.0-5.0 mg/L) after 16-20 days (93%). Highest maximum number of multiple shoots was obtained on MS medium (BAP 3.0 – 5.0 mg/L). The shoots were seaperated from the multiple-shoots, transferred to MS medium supplemented with 1.5 – 20 mg/L NAA favored roots formation occurred in most of the shoot let 88% were successfully achieved in the MS media. The rooted plantlets were transferred to polythene bags which was containing vermi compost, sand and red soil in the ratio of 1:2:2 and kept in a mist house. After acclimatization in the mist house for 2-months, it transferred to greenhouse. The plantlets were successfully planted in the field.

Effect of picloram, additives and plant growth regulators on somatic embryogenesis of Phyla nodiflora (L.) Greene

The present study describes the plant regeneration via somatic embryogenesis in suspension culture derived from the leaf and stem explants of Phyla nodiflora. The medium type, plant growth regulators, complex extract (coconut milk and malt extract) and anti-oxidant (activated charcoal, ascorbic acid, Polyvinylpyrrolidone and citric acid) markedly influenced the embryo regeneration of P. nodiflora. MS with 2,4-D and activated charcoal (10 mg/L) gave the highest stimulation of embryogenic callus growth. Optimized callus was transfered into suspension culture, which showed the globular, heart shaped embryos in MS with 2,4-D + BA + picloram (0.1 mg/L), coconut milk (10 ml/L), citric acid (100 mg/L) on 6th subcultures. Further development stages such as torpedo and cotyledonary stage embryos and fostered maturation of embryos were observed at 8th and 10th subculture. However, the high frequency embryo germination and plantlet (45 plants/20 mg cotyledonary stages embryos) formation was obtained in half-strength MS medium without growth regulators from cotyledonary embryos. All the plantlets established in the field exhibited morphological characters similar to those of the mother plant.