Articles
CULTIVATION OF ASPARAGUS PLUMOSUS SHOOT TIPS IN VITRO WITH SPECIAL REFERENCE TO VEGETATIVE PROPAGATION.
So far it has only been possible to maintain cultures in suspensions over 2 to 3 passages.
It has not been possible to induce embryogenesis, shoots or roots in any of this cultures.
A few experiments has been carried out to determine the importance of the origin of the explants, and to evaluate the influence of inorganic salts (M & S normal or half concentration with normal iron), 0,01 or 0,1 mg/1 NAA, benzyladenine (0,01 or 1 mg/1 BA) and gibberellic acid (0 or 0,1 mg/1 GA).
Explants taken from 50 to 70 cm high shoots showed that the best development of shoots was obtained with shoot tips from lateral shoots.
The apical shoot tip, the upper stem sections and the lateral buds with a covering scale were not suitable for shoot development.
The salt concentration influences growth and development of shoots from explants: Half strength of M & S inorganic salts gave better development of shoots than normal strength of M & S.
There was no difference in the development of shoots whether the NAA concentration was 0,01 or 0,1 mg/1.
BA has a great influence on the shoot growth.
The main shoot development was better with 1 mg/1 BA in the medium than with 0,01 mg/1, but the shoots were abnormally thick and with very few secondary shoots.
Secondary shoots developed best with 0,01 mg/1 and these shoots appeared normal.
Also GA was important.
Both the number of cultures developing shoots and the shoot growth were increased by 0,1 mg/1 GA.
It can be concluded that it is possible to establish a callus culture of Asparagus plumosus, but that it has not yet been possible to grow suspension cultures and to induce organogenesis in any of these cultures.
Development of shoots was best from shoot tips taken from lateral shoots.
The best development of shoots was found on a modified Murashige and Skoog medium 1) with half strength of inorganic salts, 0,01 or 0,1 mg/1 NAA, 0,01 mg/1 BA and 0,1 mg/1 GA.