HIGH FREQUENCY SHOOT REGENERATION FROM LEAF-DERIVED CALLUS IN RASPBERRY (Rubus idaeus L.)

Shoot regeneration from leaf discs excised from in vitro micropropagated raspberry plants (‘Cayuga’) was induced with high efficiency by indirect and direct organogenesis, when cultured on Lee and Fossard medium, supplemented with combinations of benzyladenine (BA) at 4.4, 13.3 or 22.2 mM, and either 2,4-dichlorophenoxyacetic acid (2,4-D) at 2.2 or 4.5 mM, or 3-indoleacetic acid (IAA) at 5.7 mM, respectively with BA (at the same concentrations mentioned above) and 3-indolebutyric acid (IBA) at 0.5 mM. The percentage of leaf discs regenerating shoots was strongly dependent of the cytokinin/auxin ratio and a significantly higher frequency of shoot regeneration was obtained from leaf-derived calli, reaching 100% when 2,4-D at 2.2 mM and BA at 13.3 mM were present in the culture medium, as compared with only 46.7-73.3% for direct organogenesis.
Not only the frequency of regenerating explants, but also the number of shoots formed per callus (with an average of 3.8) was significantly higher in the case of indirect organogenesis as compared with direct organogenesis.

Eucarpia symposium on Fruit Breeding and Genetics

A.N. Popescu, V. Isac

in vitro, indirect organogenesis, direct organogenesis

https://doi.org/10.17660/ActaHortic.2000.538.119