The effect of 2,4-D on callus induction using leaf lobe of sweet potato as a source of explant

Abstract The effect of 2, 4-dichlorophenoxyacetic acid (2,4-D) on young leaf lobes of three sweet potato accessions UE007, UK-BNARI and SA-BNARI for callus induction was investigated. Callusogenesis was achieved when leaf lobe explants from four weeks old healthy growing plantlets of three sweet potato accessions SA-BNARI, UKBNARI and UE007 were cultured on CLC/ Ipomoea medium supplemented with 1.0 - 4.0 mg/l 2,4-D with 4.0 mg/l 2,4-D being the optimal concentration. However, the calli were non-embryogenic and therefore could not produce embryos when transferred to 0.1 mg/l BAP amended medium but rather produced either single or multiple shoots. The highest percentage shoot (83.3 %) was obtained from 4.0 mg/l 2,4-D-derived callus. These results indicate that indirect shoot development via a callus phase is a feasible option for sweet potato propagation using in vitro techniques.