PH CHANGES IN CULTURE MEDIUM WITH PROGRESS OF GROWING STAGES, CALLUS, MULTIPLE SHOOT AND INTACT PLANT OF STRAWBERRY

T. Yoshihara, H. Hanyu
For developping mass propagation techniques of plantlet by liquid culture, pH changes of the culture media and the mechanisms on tissue cultured strawberry (Fragaria ananassa cv.Hoko-wase) were studied. The callus and multiple shoot were grown by LS liquid medium (Linsmaier et al., 1965) and the intact plant was grown by hydroculture medium named Enshi-shoho (Hori, 1968). The initial condition of the pH was adjusted to 6. The pH changes and the contents of media, ammonium (NH4-N), nitrate (NO3-N) and organic acids, were measured. The growth at each stage of plant was also measured. In the callus culture, the pH dropped to about 4 within first 7 days, the days corresponded to the lag phase of the callus growth. In the intact plant culture, the pH dropped to about 4 after 20 to 30 days cultivation, the days corresponded to the well growing period of the intact plant. After the droppings, the pH rose to 6 or more in both the cultures. However, a little pHchange and almost constant growth were observed in the multiple shoot culture. In the callus culture, the uptake rate of nitrate was greater than that of ammonium at the logarithmic growing phase. In the multiple shoot culture, the uptake rate of nitrate was almost equal to that of ammonium through the entire culture duration. In the intact plant culture, the uptake rate of ammonium was greater than that of nitrate. The concentration of two organic acids, considered to be Aconitic and Malic acid, changed in corresponding with the pH changes in the callus culture. It was considered that the preferential uptake of the nitrogen sources affected the pH changes. In the callus culture medium, the secretion of the organic acids also seemed to participate in the pH changes.
Yoshihara, T. and Hanyu, H. (1992). PH CHANGES IN CULTURE MEDIUM WITH PROGRESS OF GROWING STAGES, CALLUS, MULTIPLE SHOOT AND INTACT PLANT OF STRAWBERRY. Acta Hortic. 319, 291-296
DOI: 10.17660/ActaHortic.1992.319.44
https://doi.org/10.17660/ActaHortic.1992.319.44

Acta Horticulturae