A REFINED TISSUE CULTURE MEDIUM FOR IN VITRO PROLIFERATION OF APPLE ROOTSTOCKS

In the present investigation, a protocol for tissue culture of apple rootstocks, using nodal sections from cv. ‘MM111’ and cv. ‘MM106’, was developed.
In order to inhibit the production of phenolic compounds, which are released at the induction stage, combination of ascorbic and citric acid was compared with activated charcoal.
The results suggested that the best initiation medium contained full MS medium plus a combination of ascorbic acid and citric acid. The cultures were kept at 4ºC in the dark for six days, and then were transferred to a culture room of 21±1ºC with 16/8 hour light/dark cycle.
To optimize multiplication rate, treatments of BAP (0, 1, 2, 4 µM) in combination with GA₃ (0, 3, and 6 µM) were applied.
Average maximum number of axillary shoots (4.8) and new leaves per regenerated shoots (6) were obtained on the medium containing MS + 2 µM BAP + 3 µM GA₃ for ‘MM111’. The best multiplication medium for ‘MM106’ contained 4 µM BAP, where the average maximum number of axillary shoots (6) and new leaves per explant (5.6) were achieved.
When the level of GA₃ was increased to 6 µM, maximum increase in stem height for ‘MM111’ (20.6 mm) and ‘MM106’ (14 mm) were obtained.

VI International Symposium on In Vitro Culture and Horticultural Breeding

M. Jafarkhani Kermani, Z.S. Hosseini , A.A. Habashi

apple, induction stage, Malling-Merton rootstocks, micropropagation, phenolic compounds

https://doi.org/10.17660/ActaHortic.2009.829.48