Somatic embryogenesis and plants from zygotic embryos of coconut (Cocos nucifera L.) in vitro

Complete plants were grown from zygotic embryos cultured on Y3 basal liquid medium supplemented with coconut milk, BA and NAA. Explants from stem, leaf and rachilla of mature coconut trees turned green and swelled on Y3 semi-solid basal media supplemented with 2,4-D, K, NAA, BA and activated charcoal. Callus was initiated in explants from the subapical regions of the stem on Y3 basal medium supplemented with 2,4-D (4.52×10²M). Globular embryo-like structures were obtained when this callus was subcultured to auxinless medium. Root formation was obtained from leaf explants on Y3 basal medium containing citric acid, ascorbic acid and 2,4-D (4.52×10² M). Globular embryo-like structures were also obtained directly from leaf explants on a Y3 basal medium supplemented with 2,4-D (2.26×10² M). Callus isolated from rachilla explants on Y3 basal medium containing 2,4-D(4.52×10² M), formed nodular structures when transferred to medium with 2,4-D (2.3×10¹ M). These nodules developed roots from the base of the nodular growth whereas from the upper portion shoots were observed on Y3 basal liquid medium.Abbreviations K kinetin - BA Benzyl adenine - 2,4-D 2,4-Dichlorophenoxyacetic acid - NAA Naphthalene acetic acid - CM Coconut milk - IAA Indole acetic acid - 2iP N⁶-r-r-dimethyl allyl amino purine NCL Communication No. 3471