In vitro morphogenetic response of apple (Malus domestica Borkh.) and pear (Pyrus communis L.) to the elevated levels of copper and myo-inositol

Abstract

The elevated levels of copper and myo-inositol in the MS medium were demonstrated to enhance culture growth and morphogenetic response of apple and pear explants. The results revealed that the highest number of branches per explant (2.80) for apple was obtained from the levels of 0.0+ 100 and 0.050+400 mg/l of both copper and myo-inositol, respectively (C1M2 and C4M4), while for pear 3.40 branches per explant were achieved from the same treatment. The mean length of branches was significantly lower in the case of the control treatment (the absence of copper and inositol). The highest number of leaves per explant (29.73 and 29.80) for both apple and pear, respectively, was recorded for treatment C4M4 (0.050+ 400 mg/l of both copper and myo-inositol, respectively. At the rooting stage, the elevated levels of copper and myo-inositol were very effective in stimulating root formation in both apple and pear shoots. The highest number of roots in apple (2.00 roots/ explant) was achieved while using 0.100+ 800 (C5M5) of both copper and myo-inositol, whereas the highest number of roots for pear (3.17 roots/ explant) was recorded for C6M6 (0.200+ 1600). The highest mean length of roots for apple reached 1.23 cm in treatment C3M3 and 1.10 cm for pear in treatment C6M6. These data suggest that the higher levels of copper and myo-inositol enabled shoot and root formation in the explants, and it might be necessary to use higher levels of these two medium components in order to enhance morphogenetic potential of explants.