Somatic embryos formation from immature cotyledons in<em> Phaseolus vulgaris</em> cv. CIAP 7247

Abstract

Common bean, like most of legumes, is recalcitrant to in vitro culture, so the establishment of a regeneration procedure via somatic embryogenesis in this specie has not been possible. Therefore, determining the effect of factors that influencing on somatic embryos formation constitutes an essential step to develop a regeneration protocol via somatic embryogenesis in common bean. Cotyledons of immature seeds were used as initial plant material to achieve the somatic embryos formation in Phaseolus vulgaris cv. CIAP 7247. Five 2,4-D concentrations (10, 20, 30, 40 y 50 mg l-1) and cotyledon orientation on culture medium were studied. After eight weeks on culture, the number of explants that formed somatic embryos and the number of somatic embryos per explant were evaluated. The results demonstrated that the major number of explants that formed somatic embryos and the number of somatic embryos formed per explant were obtained with 40 y 50 mg l-1 of 2,4-D. Somatic embryos were formed on abaxial side from the cotyledons when this side was placed opposite to the culture medium. Somatic embryos on cotyledons from immature seeds of Phaseolus vulgaris L. cv. CIAP 7247 were formed. It was demonstrated that the addition of 2,4-D into culture medium, and the explant orientation had a determining effect on somatic embryogenesis in this important legume. Key words: common bean, regeneration, somatic embryogenesis