EFFECT OF CHITOSAN AND PUTRESCINE-ANCHORED NANOCARBON ON THE in vitro PROPAGATION OF THE APPLE ROOTSTOCK MM106

Apple is one of the most important fruit crops cultivated in temperate regions worldwide. This study aimed to develop an efficient protocol for shoot multiplication and root induction during the in vitro propagation of the apple rootstock MM106. The results showed that the MM106 rootstock responded variably to chitosan (CS), polyvinylpyrrolidone (PVP), and thidiazuron (TDZ) concentrations during micropropagation. The highest shoot multiplication rate and shoot quality were obtained on MS medium supplemented with 0.1 mg L⁻¹ TDZ, 10 mg L⁻¹ CS, and 0.3 g L⁻¹ PVP during the long phase of shoot multiplication on the MS-medium. The addition of kinetin to the TDZ–CS–PVP combinations reduced the shoot multiplication rate. 1 mg/L IBA with 0.3 g/l PVP was the most effective concentration in the rooting phase, and 83.3% of shoots were rooted by adding carbon nanotubes (CNTs), putrescine (Put), or phloroglucinol (PG) separately at varying concentrations (with IBA + PVP) significantly increased rooting percentage, root number per shoot, root length, rooting speed, and lateral roots.