In vitro propagation of apple (Malus x domestica Borkh.) cv. Lal Ambri

The investigation was performed during the year 2007–09 to determine the effect of different antioxidants, plant growth regulators and media on different micropropagation stages of apple cv. Lal Ambri. For culture initiation and to inhibit the production of phenolic compounds released at this stage, forced explants cultured on MS basal media fortified with different combinations of ascorbic acid and citric acid were subjected to two different temperature regimes (4±3°C initially for 3 days in the dark and then transferred to a normal culture room conditions of 23±1°C with 16/8 hour light/dark cycle and another set kept at normal incubation conditions.). The results suggested that the explants maintained initially at 4±3°C for 3 days under complete darkness supplemented with combination of ascorbic acid 100mgl⁻¹ and citric acid 150mgl⁻¹ gave maximum percent (44.21) culture initiation. Maximum establishment (40.11%) of the cultures were obtained in MS medium fortified with BAP + IBA at 0.50+0.05 mgl⁻¹. To optimize proliferation rate, microshoots from the establishment media were transferred to the proliferation medium. Highest proliferation rate (5.96 shoots/explant) was achieved in MS medium supplemented with BAP+Kn at 0.50+0.50 mgl⁻¹. However maximum increase in microshoot length (26.33 mm) was achieved in treatment combination of BAP and Kinetin each at 0.25 mgl⁻¹. This study indicates that in vitro shoot tip micropropagation would be an excellent way to rapidly increase the number of Lal Ambri plants.