Desarrollo del saco embrionario asociado a la formación del embrión de yuca in vitro

Abstract

Cassava is an important crop in subsistence farming, marginal and highly vulnerable environments. Genetic improvement of cassava is inefficient due to its genetic complexity and lack of basic knowledge about its reproductive biology. The differentiation of plants from in vitro culture of haploid cells is an efficient alternative to produce homozygous populations (double haploids, DH) to develop varieties with desired characteristics that would increase crop productivity, or for the identification of recessive traits, production of genetic stocks for conservation and exchange of genetic diversity. To develop this technique, data on the formation and development stages of male and female gametophytes of cassava are needed. In the case of DH obtained by female unfertilized gametophytes (gynogenesis), knowledge about the maturation stage of the embryo sac in which the division of the unpollinated egg cell can be induced, and the optimal conditions to allow the complete embryo development in the unfertilized embryo sac, allowing its germination and plant development. The objective of this research was to identify the optimal development of the embryo sac and the earliest stage at which can be induced in vitro development of zygotic embryos and their conversion into plants, for use as a model for in vitro embryo and plants induction from unfertilized eggs in cassava. To achieve this, the structural and cellular changes were documented in various stages of development of the embryo sac of fertilized and unfertilized female flowers of a line of cassava (SM1219-9).