The effect of different hormone combinations on direct and indirect somatic embryogenesis in Agave americana

Abstract

<span><span style="font-family: Calibri; font-size: medium;">Direct and indirect somatic embryogenesis in Agave <em>Americana</em> through basal parts of micropropagated shoots were considered in this study. For micropropagation, 2 factors (BA and NAA) were utilized in different concentrations. A factorial experiment based on a completely randomized design (CRD) was accomplished with four replicates in a modified Murashige and Skoog medium (MSB). BA in 3 mg/L along with NAA in 0.1 mg/L was the best treatment for multiplication. Callus and embryo induction were evaluated using different auxins in a CRD experiment with three replicates in MS medium supplemented with L2 vitamins. Picloram 2.5 and 2 mg/L and also Dicamba 1 mg/L induced 66.7%, 60%, and 53.3% of explants to somatic embryo, respectively. Also, 2,4-D 2 mg/L had the highest impact on callus induction (95.6%). Embryogenesis was studied using Dicamba and Picloram in the same culture medium in a factorial experiment based on CRD with three replicates. The results of orthogonal polynomial analaysisindicated that high concentrations of Dicamba from 0 to 1.5 mg/L had a significant effect on somatic embryo induction. However, higher concentrations had the opposite effect on somatic embryo numbers. Germination of somatic embryos was performed in MSB medium without growth regulators.</span></span> <span><span style="font-family: Calibri; font-size: medium;"> </span></span>