INTERSPECIFIC HYBRIDIZATION ADVANCES IN THE GENUS EUSTOMA
Eustoma grandiflorum (Raf.) Shinners, commonly known as Lisianthus, is a relatively new ornamental crop. It has gained economic importance over the years due to its outstanding ornamental traits, such as the size and color of the flowers, which ranges from white to deep purple. The genus is distributed from southern United States to Central America, including the Caribbean islands; nevertheless, E. grandiflorum is restricted to southern United States through to northern Mexico. As in many other crops, interspecific hybridization is one of the most important tools to generate genetic variation and to achieve introgression of coveted traits into new cultivars. In order to accomplish genetic variation, several inter-specific crosses were performed between different Eustoma cultivars and to E. exaltatum in different directions. The results of these crosses are depicted in this work, where hundreds of hybrids were obtained, some of them, showing extraordinary traits, such as different color patterns, stem and flower size and heat tolerance. Additionally, chromosome counts and rDNA in situ hybridization to metaphasic chromosomes were performed, determining the basic chromosome number of 2n = 2x = 72 for E. exaltatum. Furthermore, an in vitro culture protocol for E. exaltatum was established, involving different basic media cultures (MS and B5) and different concentrations of growth regulators (BA, KIN, and GA3) resulting in up to ten shoots per explant, with an average of 10 mm length. The results presented in this work, give an insight into inter-specific hybridization, chromosome numbers and in vitro propagation protocols in the genus Eustoma.
Barba-Gonzalez, R., Tapia-Campos, E., Lara-Bañuelos, T.Y., Cepeda-Cornejo, V., Dupre, P. and Arratia-Ramirez, G. (2015). INTERSPECIFIC HYBRIDIZATION ADVANCES IN THE GENUS EUSTOMA. Acta Hortic. 1097, 93-100
breeding, chromosome number, in situ hybridization, micropropagation, ornamental