OPTIMIZATION OF TISSUE CULTURE MEDIA FOR PROPAGATION OF MARIANNA ROOTSTOCKS

Marianna rootstock is used predominantly in South Africa for cultivation of plum cultivars. In order to develop an adventitious regeneration system for plant transformations, shoot cultures should been grown in vitro. Initially shoot cultures of Marianna rootstock were propagated on K2 salts, but the cultures declined over time. Therefore, eight different growth media were tested for improved proliferation of the cultures. Two of these eight supported good growth, and they were optimised further. The results showed that the in vitro shoots grew much better when cultivated on MS medium with phloroglucinol or a combination of phloroglucinol and gibberellic acid.