CLONAL MULTIPLICATION OF AZALEAS THROUGH TISSUE CULTURE

Tissue culture procedures were developed for clonal multiplication of hybrid selections of azales (Rhododendron sp.). Shoot tips (1–3 mm) were explanted in modified Murashige and Skoog medium (1962) containing ½ or 1/3 strength of major elements, and, in mg/1, inositol, 100; thiamine hydrochloride, 0.4; kinetin, 5; malt extract, 500; and Bacto-agar, 7 000. Coconut milk was included at a rate of 20% (v/v). Survival and growth were improved noticeably by adding a small volume of liquid nutrient to 3-week-old cultures and rotating them gently for 5 dáys, then returning for further development in the stationary state.
Shoot proliferation began with the emergence of axillary shoots.

Subculture of the shoots in the same medium or in a medium without malt extract and coconut milk resulted in the formation of multiple shoots through axillary branching.
Substantial quantities of shoots were obtained through repeated subcultures.

Regeneration of plants was accomplished by rooting the shoot clusters in a medium of low salt concentration and without auxin.
Rooted plants made vigorous growth after transferring first to sphagnum moss and then to soil, under mist in the greenhouse.

Symposium on Tissue Culture for Horticultural Purposes

S.S. Ma, S.O. Wang

https://doi.org/10.17660/ActaHortic.1977.78.27