Caracterización del sistema de reproducción y ploidía de plantas ornamentales a partir de gramíneas nativas para paisajes urbanos de bajo mantenimiento

The native and naturalized species of the province of Cordoba, particularly grasses, have the potential to become elements of low-maintenance garden design. The aim of this Thesis was to develop the first stage of selection of grasses with landscape and ornamental characteristics, from native and naturalized genetic resources. For this purpose, the distribution of the species and the climatic or edaphic variables that can model their presence were studied. To the best of our knowledge, the distribution models of many of these species have been described for the very first time in this work, despite being a tool widely used in ecological niche studies. Furthermore, the growth habits of the plants and the color of their leaves and inflorescences throughout the seasons were characterized. Potential consumer preferences of native plants and reaction to low-maintenance design proposals were also preliminarily analyzed. Ecological niche maps of 14 species and the respective results of the Jackknife test were obtained. The most important climatic and soil variables were observed, and their response curves were shown. These maps provided essential information for the combination of native species in gardening projects. The color measurements and the descriptions of the growth habit showed a great diversity within the native and naturalized grasses of the province. Species with blooms in different months were presented. Preliminary results of people’s appreciation of native materials for gardens were shown, as well as the valuation of gardens made with native plants. Certain aspects were highly valued by potential consumers such as average height and the presence of large flowers – native dicotyledonous plants. In grasses, it was important the average height, its native origin as well as long flowering periods. The case of Jarava ichu was extensively analyzed, as it is one of the native grasses with the greatest ornamental potential due to its extensive area of distribution and good acceptance in gardens in arid regions. The reproductive method, ploidy and chromosome number were studied setting the basis for further genetic studies and the development of breeding programs and germplasm conservation plans. By means of embryological analysis, flow cytometry and controlled pollination, it was determined that Jarava ichu reproduces sexually and is preferably allogamous. The results of cytogenetic analysis suggested that Jarava ichu would be tetraploid (2n=4x=40). These results will contribute to establishing a group of native and naturalized species of the province with ornamental potential in future breeding plans and garden designs.