Effect of cytokinins and auxin on bud burst and direct organogenesis <i>in vitro</i> of some sweet potato landraces (<i>Ipomoea batatas</i> L.) grown in Benin

Abstract

Objectives: Ipomoea batatas L. is a tuberous root plant of great nutritional and economic importance in Benin. This study aims to analyze the effects of two cytokinins (Benzylaminopurine and kinetin) and a one auxin (Naphthalene Acetic Acid) on direct organogenesis in vitro of six sweet potato landraces in Benin.

Methodology and Results: Ten uninodal stems disinfected of each variety are cultivated on a Murashige and Skoog (MS) medium then transplanted onto other MS media with different combinations of Benzylaminopurine, Kinetin and Naphthalene Acetic Acid. Their vitroplants are also acclimatized. Analysis of variance was used for data analysis. The results showed that '' Amitchéwin, Vobodouaho and Koïdokpon '' have recorded the highest average bud burst (12.67, 12.33 and 11.67 respectively). The media MS + 1 mg.l^-1 BAP + 0.1 mg.l^-1 NAA and MS + 1 mg.l^-1 Kin + 0.1 mg.l^-1 NAA were found more effective for the organogenesis of the varieties. Vitroplants of each variety acclimatized well with survival rates ranging from 56.66% to 83.33%.

Conclusion: and application of results: The results showed that the combination of 1 mg.l^-1 of Benzylaminopurine or kinetin with 0.1 mg.l^-1 of Naphthalene Acetic Acid was effective for in vitro organogenesis of sweet potato landraces used with well-acclimated vitroplants. This study paves the way for the establishment of in vitro collection of sweet potato landraces in Benin with a view to their ex situ preservation.

Keywords: Ipomoea batatas; growth regulators; organogenesis in vitro; Acclimation; Benin