In vitro somatic embryogenesis and plant regeneration from mango (Mangifera indica L.) nucellar callus.
DeWald S. G.
Author Affiliation: Univ. Florida, Gainesville, FL 32611, USA.
Dissertation Abstracts International, B (Sciences and Engineering) 48 : 2165B-2166B
Abstract : Histological analysis revealed the nucellar origin as well as the variable location of adventive embryos within the micropylar portion of the ovules. Adventive nucellar embryos, characterized by densely staining cytoplasm and prominent nuclei, were formed prior to the cellularization of the endosperm. Embryogenic callus was initiated from the micropylar and chalazal portions of excised nucelli. In suspension culture, proliferation occurred via secondary budding from the epidermis of preformed somatic embryos. These somatic embryos exhibited numerous developmental abnormalities; normal embryo development occurred on solid medium. Embryos had bipolar meristems with closed vascular systems, thus demonstrating the embryogenic nature of plant regeneration from nucellar callus in mango. Embryogenic efficiency of callus was improved by transfer to solid medium containing glutamine, 2,4-D and kinetin. Germination of somatic embryos occurred on medium where sucrose concentration was sequentially lowered and the synthetic growth regulators were replaced by 20% liquid coconut endosperm and 0.025% casein hydrolysate. Plants were regenerated and established in soil.