Liquid medium culture of Quercus suber L somatic embryos comparation between liquid and solid culture and among different growing media

The objective of this study was to overcome two of the limiting factors of the standard culture protocol, in agar solidified medium, of cork oak somatic embryos: the low rate of mature embryos obtained, and the high labor and time consumed. First experiment. Immature somatic embryos of 2 mm. length were cultured for 30 days in four different growing media: 1/2SH{*}, SH{*}, 2xSH{*} and MS, both in solid and liquid phase. Higher fresh weights were detected, in every media, using liquid culture. In relation to developmental pattern, liquid culture in 1/2SH{*} has demonstrated to be the most effective combination for the first developmental stages producing lower percentages of secondary embryogenesis. Second experiment. Immature somatic embryos were cultured for 15 days in liquid 1/2SH{*} and transferred to the four different media. The richest media were shown to be more appropriated for the maturation stage giving higher rates of mature embryos.