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

Abstract

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 (4.52×10²μM). 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 μM). Globular embryo-like structures were also obtained directly from leaf explants on a Y3 basal medium supplemented with 2,4-D (2.26×10² μM). Callus isolated from rachilla explants on Y3 basal medium containing 2,4-D(4.52×10² μM), formed nodular structures when transferred to medium with 2,4-D (2.3×10¹ μM). These nodules developed roots from the base of the nodular growth whereas from the upper portion shoots were observed on Y3 basal liquid medium.