OPTIMIZATION OF CULTURE MEDIA FOR IN-VITRO ROOTING OF MALUS-DOMESTICABORKH CV COMPACT SPARTAN

Shoots of Malus domestica Borkh. cv. Compact Spartan raised in vitro d o not root in a single auxin medium. Components of the rooting medium were tested not only for root initiation but also for root elongation. Root emergence and further growth were inhibited by a too prolonged a uxin treatment, the presence of NH4NO3 and the lack of substrate aerat ion. Saccharose was essential to achieve highly reproducible root grow th on agar but was not necessary on watered vermiculite. Ca(NO3)(2) st imulated root initiation, emergence and growth and improved their viab ility.