Abstract
We attempted in vitro preservation of cultured shoot primordia and somatic embryos of melon by examining incubation temperature, sucrose concentration in the medium, and the inclusion of abscisic acid and its treatment period. Cultured shoot primordia of melon (cv. Prince) were successfully preserved for 40 days at 15°C in a liquid MS medium containing 3% sucrose and 10mg/l ABA rotated at 2rpm. Inclusion of a higher concentration of sucrose (10%) or incubation at 5°C reduced viability and shoot regeneration after storage. Somatic embryos of melon (cv. Sunday Akigata) were best preserved for 30 days on a half strength MS medium with 3% sucrose and 0.2% gelrite and in the absence of ABA at 5°C. Inclusion of 10% sucrose or ABA resulted in a decreased rate of regrowth. By these growth retarding methods, subculture intervals of cultured shoot primordia could be extended and somatic embryos could be arrested at a particular growth stage. Somatic embryos seemed more tolerant to low temperature than cultured shoot primordia.
