Artificial endosperm of Cleopatra tangerine zygotic embryos: a model for somatic embryo encapsulation

Synthetic seed technology may be of value in breeding programs and allow th e propagation of many elite genotype-derived plants in a short time. In thi s work, a range of artificial endosperm treatments of Cleopatra tangerine z ygotic embryos were evaluated for suitability for encapsulation of somatic embryos. Different complexing ions in the form of alginate capsules, zeolit e as an ion exchanger and the relationship between capsule-nutrient gel on germination of zygotic embryos, were evaluated. Artificial endosperm assays showed that abscisic acid (1 mu M) and mannitol (0.25 M) delayed germinati on and conversion of zygotic embryos, whereas amino acid supplements (proli ne, glutamic acid and arginine) accelerated the conversion process. An arti ficial endosperm was used to encapsulate somatic and zygotic embryos. After encapsulation, zygotic embryos germinated after four days of culture while somatic embryos germinated asynchronously after 20 days. Somatic embryo-de rived plantlets showed greater vigour than zygotic embryo-derived plantlets . Results showed that this artificial endosperm is adequate for Cleopatra t angerine somatic embryo germination and conversion into plants.