REGENERATION OF Agave marmorata Roelz PLANTS IN TEMPORARY IMMERSION SYSTEMS, VIA ORGANOGENESIS AND SOMATIC EMBRYOGENESIS

Abstract

Background. The genus Agave has social, cultural, environmental and economic importance in Mexico. Approximately 15 species of agave are used as raw material for the production of mezcal, among them is the Agave marmorata Roelz, which is considered the longest-lived agave for the preparation of this drink because its maturation period ranges from 20 to 35 years. Agave plant tissue culture is a technique that allows obtaining plants by organogenesis (O) and / or somatic embryogenesis (ES) in a short period of time. The quality and quantity of plants propagated by these methods can be favored with the use of Temporary Immersion Systems (SIT). Objective. Establish a protocol for the regeneration of A. marmorata seedlings in SIT, with the methods of direct organogenesis and indirect somatic embryogenesis. Methodology. Two regeneration methods, direct organogenesis and indirect somatic embryogenesis, were evaluated. For the first, the effect of the frequency and number of explants grown in SIT in the sprouting and growth stages of the explant was determined. For the second, the effect of the number of explants grown in SIT on the percentage of germination and the growth rate of somatic embryos was evaluated. Results. The best treatment in the sprouting stage was obtained with 80 explants grown in SIT with an immersion frequency of 8 h and an immersion time of 2 min, with 84% sprouting and 17.5 sprouts / explant of 1 cm in height. The best growth of the explants originated from direct organogenesis was obtained with 180 cultured explants per flask with an immersion frequency of 8 hours and an immersion time of 2 min. On the other hand, in the somatic embryogenesis method, the highest percentage of embryo germination (62.2%) was achieved with 80 somatic embryos cultured in SIT with an immersion frequency of 8 hours. Implications. The results of this research contribute to a better understanding of the regeneration process of direct organogenesis and somatic embryogenesis in temporary immersion systems. This can help to scale the system commercially and to conserve germplasm. Conclusions. It was possible to establish an effective protocol for the regeneration of agave seedlings.