Dehydration and cryopreservation of Handroanthus serratifolia embryos

Abstract

Handroanthus serratifolius typifies species found in the Cerrado biome and is grown as a tree for ornamental purposes, lumber and furniture. Since the species produces orthodox seeds which loose viability rapidly, cryopreservation presents an option for long-term conservation. The objectives of this study were to test methods to dehydrate and thaw excised embryos to obtain maximum survival following exposure to liquid nitrogen. Embryos that were previously moistened by surface sterilization treatments were dried for 0 to 300 min either in a laminar flow hood and then stored for seven days in liquid nitrogen. Embryos were thawed in a water-bath at 38°C for 1 to 5 min and then sown on MS germination medium containing 0.5 mg/L GA3. Germination percentage and shoot length were evaluated after 15 days of culture. Drying duration significantly affected survival of cryo-exposed embryos. Germination percentages greater than 85% were obtained in H. serratifolius embryos that were dried to less than 10% water before exposure to LN.