In vitro induced cold memory fails to enhance embryogenic cultures development in Araucaria angustifolia

This research aimed to study how exposing somatic embryos of Araucaria angustifolia to cold temperatures in vitro could enhance somatic embryogenesis. The somatic embryos were induced from immature zygotic embryos, grown for 120 days, and then subjected to 4.5°C for 0, 2, 4, 8, or 16 days. After the cold treatment, the embryogenic cultures were returned to 25±2°C for 20 days and examined using light microscopy and cytochemistry. It was found that the embryogenic cultures at the PEM III stage did not show further development, and the growth of the embryogenic masses was negatively affected in the longer-duration cold treatment. Overcoming these challenges in the somatic embryogenesis protocol for A. angustifolia requires further integrative investigations on epigenetic events driving the zygotic embryo development.