Thin cell suspension layer as a new methodology for somatic embryogenesis in Agave tequilana Weber cultivar azul

Commercial micropropagation of plants is enhanced with the use of liquid media cultures; however the presence of hyperhydricity is commonly observed in cultures of the succulent plant Agave tequilana Weber cultivar azul, this phenomenon persists even with the use of temporary immersion systems (TIS). Thin cell suspension layer technology is proposed to solve this problem. This technology fuses the advantages of a liquid culture made through cellular dissociation, and the use of solid medium for somatic embryogenesis expression of the species. The technology was evaluated by means of two experiments in order to know the influence of gelling agent phytagel®, and of sucrose concentrations through interaction with three cellular suspension densities. It was clear that concentrations of phytagel at 6, 8, 10 or 12 g l-1 are not significant for embryoid expression of A. tequilana. On the other hand, sucrose at 30 and 60 g l-1 have statistically superior values than concentration of 120 g l-1. A larger cellular density (161 × 103 cells ml-1) gave a statistical difference in number of embryoids. The advantages of thin cell suspension layer were remarkable: it encouraged complete expression of embryoids without transfer to extra media cultures, and a higher number of generated embryoid was obtained. Absence of hyperhydricity was observed in all regenerants. © 2008 Elsevier B.V. All rights reserved