Production of interspecific hybrids between Nierembergia ericoides and Nierembergia linariaefolia through the application of embryo rescue techniques
Víctor José Milicia1*, Ángel Chiesa1, Andrea Coviella2 y María Silvina Soto2
Interspecific hybridization is one of the most widely used techniques in the improvement of ornamental plants because of its high potential to obtain hybrid vigor and character variation, which are not expressed in the original species. The aim of this study was to obtain interspecific hybrids of Nierembergia ericoides Miers × N. linariaefolia Graham using the embryo rescue technique through ovule culture as a tool to overcome post-zygotic barriers. The ovules were isolated 7 days after crosspollination and cultured in modified Murashige and Skoog (MS) medium. Three sowing dates were carried out: A: 3/10/17; B: 3/11/17; C: 13/12/17. The ovules, whose embryos began their development (those with the radicle emerged), were placed into test tubes with modified MS culture medium. The tubes were placed in a culture chamber at 25°C with a photoperiod of 12 hours and a light intensity of 4000 lux. The number of germinated ovules was compared to the total number of cultured ovules, while the number of seedlings obtained was compared to the number of germinated ovules. Five seedlings were obtained from 931 ovules cultured on the first date, and the same number was obtained from 642 ovules cultured on the second date. A fungal contamination occurred on the third culture date, which prevented data collection. It can be concluded that embryo rescue by the culture of Nierembergia ovules successfully allowed obtaining effective crosses between incompatible species.
Key words: Post-zigotic barriers, ornamental plants, breeding, in vitro cultivation, native plants.
1 Facultad de Ciencias Agrarias, Universidad Nacional de Lomas de Zamora, Ruta Provincial Nº 4 y Juan XXIII, Lomas de Zamora, Argentina.
2 Instituto de Floricultura, Instituto Nacional de Tecnología Agropecuaria, Nicolas Repetto y de los Reseros s/n (1686), Hurlingham, Argentina.
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