Effect of 2, 4-D and NAA on callus induction in date palm cultivars Halawy and Medjool

In the present investigations two popular cultivars (Halawy and Medjool) of date palm were selected for in vitro callus formation. The effect of different levels of 2, 4-D (25, 50 and 100 mg/l) and NAA (25, 50 and 100 mg/l) in combination with BA (3 mg/l) was studied. The maximum responsive culture was observed with 2, 4-D (100 mg/l) + BA (3 mg/l). The addition of BA 3 gm/l activated charcoal in MS basal medium when taken from shoot tip explant. This treatment was found to induce earliest callus formation (146 days) as compared to other treatments. However higher concentration of auxin was found to aggravate the growth of the callus and maximum weight of callus was recorded with low concentration of auxin. The quality of callus was also affected differently with all combinations of treatments. The embryogenic calli were developed after 6 months of callus which was sub-cultured on fresh MS basal medium without hormone.