Improved protocol for efficient regeneration of coconut (Cocos nucifera L.) anther derived embryos

Abstract

CaCl 2 on the reduction of shoot necrosis was also tested. CaCl 2 showed a significant (p = 0.001) effect on reducing the shoot necrosis. The lowest occurrence of shoot necrosis (25.0 %) was observed in 4.0 mM CaCl 2 treatment. Continuous sub-culturing of shoots with initial signs of shoot necrosis to elevated CaCl 2 levels until the rooting stage facilitated the recovery. Transfer of the shoots frequently into a fresh medium was not beneficial for the suppression of necrosis. Shoots maintained in the medium enriched with 4.0 mM CaCl 2 were transferred for acclimatisation, and this is the first report of transferring haploid coconut plants to acclimatisation conditions. The rooted shoots produced through the optimised protocol were acclimatised successfully. The prevention of shoot loss due to shoot necrosis will be beneficial for further refinement of the coconut anther culture protocol.