| Popis: |
Plumule tissues have found to be more responsive explants for clonal propagation of coconut. In the present study, the feasibility of using plumule explants for clonal propagation of a local coconut variety (Sri Lanka Tall) was assessed. Plumules were cultured in three basal media (MS, Y3 and 72) supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D) (24 - 400 \M) and activated charcoal. Somatic embryogenesis and plant regeneration were induced by incorporating of abscisic acid (ABA) into the medium. Attempts were made to improve plant regeneration by applying high agar concentration-induced water stress, cytokinin or silver nitrate in combination with ABA. The results revealed that callus can be initiated from plumule explants cultured in all three basal media tested. The callus formation depended on the concentration of 2,4-D in the media and the best effect was observed with the lower level (24 jiM) tested. The plant regeneration frequency observed with ABA treatment was 4.4 %. The combination of ABA with high agar concentration-induced water stress doubled the plant regeneration frequency. About 50 % of the regenerated plants could be successfully acclimatized and field planted. The results of the study indicate the possibility of regenerating plants from plumule explants of coconut. The method can be used for multiplication of improved seed material. However, the plant regeneration efficiency should be further improved for mass scale propagation of coconut using plumule explants. |
