Effect of water content and biochemical cell state on the germination rate of cryopreserved Butia eriospatha embryos (Arecaceae)

Rain forest in Brazil is home of around 50% of the world’s plant biodiversity and many species have a high economical potential. Butia eriospatha is an endemic species of the Brazilian Atlantic Forest and due to the anthropic intervention, it is in a vulnerable conservation status. In this species, plants are only propagated sexually by seeds which show dormancy and have a low germination rate, combined with slow seedling emergence. To manage the limitation of the seedling establishment and conservation strategies of this species, the viability, antioxidant activity, and profiles of polyamines and amino acids of desiccated B. eriospatha embryos were assessed. Mature and desiccated embryos were germinated under in vitro conditions on Murashige and Skoog culture medium, which was supplemented with hormones and antioxidants. Embryo desiccation tolerance threshold was 0.14 g H 2 O g DW −1 with a germination rate of 93.3%. During embryos desiccation was observed a significant increase in putrecine (PUT). Increase in guaiacol peroxidase (GPX) and ascorbate peroxidase (APX) activity led us to suggest that they are the main enzymes involved in cellular protection during desiccation. An increase of amino acids content, especially glutamic acid (Glu), leucine (Leu), lysine (Lys), glutamine (Gln), which are known as osmoprotectors also was observed. Embryos previously desiccated to 0.14 g H 2 O g DW −1 were successfully cryopreserved, and showed a post-thawing recovery rate of 85%. The physiological and biochemistry approach of this study associated to a cryopreservation protocol can be used for plant genetic resources conservation of other Arecaceae species in the world.