S05 - Session O4 - Morphological and molecular characterization of interspecific hybrids (Cosmos atrosanguineus x Cosmos purpureus)

Authors: Diana Erika Gómez Pedraza *, Bulmaro Morales Vazquez, Bulmaro Morales Vazquez, Maria Teresa Martínez Damián, Maria Teresa Colinas León, María de Jesús Juárez Hernández

Cosmos atrosanguineus , a species better known as chocolate cosmos, is a plant with a high ornamental value due to the presence of a chocolate fragrance in its flowers. It is an endemic species of Mexico and it had been reported extinct from its natural environment. However, small populations of wild material have been found in recent years. In order to obtain new varieties that can be registered and commercialized, a breeding program was started through interspecific hybridization with Cosmos purpureus . The female plant used was the species Cosmos atrosanguineus and the pollen donor was Cosmos purpureus . The hybrids presented intermediate phenotypic characteristics to the parents and for some characters they presented characteristics more similar to some of the parents. Only 15% of the hybrids had chocolate fragrance. The hybrid nature of the materials obtained was confirmed by ISSR-type molecular markers; closer genetic relationships with the female parent were observed due to the triploid nature of the hybrids. This study shows that it is possible to carry out genetic exchange between these two species, to generate varieties with the best morphological attributes of both species.