Popis: |
Somatic embryogenesis has been accomplished from tender leaf base explant of date palm (Phoenix dactyliferaL.). Three to five mm long tender leaf base explants derived from the meristamatic region of 2-3 year old offshoots of date palm cv. Kheneizi were cultured on Murashige and Skoog (MS) basal medium supplemented with 10, 50, 100 and 150 mg l-1 2,4-dichlorophenoxy acetic acid (2,4-D) and incubated in dark for 6 weeks to initiate callus. Callogenesis was obtained in all 2,4-D concentrations tested; however, callus growth was most significant in media supplemented with 100 mg l-1 2,4-D. The leaf explants with callus were transferred to hormone-free MS medium for 4 weeks and then further sub-cultured to a medium supplemented with 0.5 mg l-1 ?-naphthalene acetic acid (NAA) and 0.25 mg l-1 6-benzyl amino purine (BAP) which was effective in inducing shoot and root primordia within 10 weeks. In another 12 weeks, two more sub-culturing of shoot clumps in the same medium resulted in the development of shoot with roots and gave whole plants by 8 weeks. The plantlets were hardened and acclimatized to the ambient conditions and planted in pots, containing 1:1:1 peat, sand and dehydrated cow manure, which resulted in over 60% ex vitro plant survival. Early plant regeneration was achieved by this technique. |