Production of inter-specific hybrid between Populus caspica and P.nigra using mature embryo culture

Mature ovary culture was used to develop inter-specific hybrid between Populus caspica L. and P. nigra. Manual pollination of Populus caspica، female flower was conducted by P. nigra L. pollen grains، using twigs and pod breeding system. Developed ovaries in different developmental stages (10، 14 and 21 days after pollination) were then aseptically transferred to hormone growth regulator free MS culture media supplemented by two different sucrose concentrations (30 and 60 g/L) for embryo germination. Analysis of collected data indicated that there were highly significant differences between embryos age for germination at α=0. 01 level. Fourteen days old embryos showed highest embryo germination (85%) then the other two There were no differences between culture media for embryo germination but highly significant differences was observed between culture media for growth rate of plantlets at α=0. 01 level. MS medium supplemented with 60 g/L sucrose showed 4. 41 cm growth rate while average 2. 09 cm was observed for MS medium containing 30 g/L. Plantlets were transferred to the same medium within jars، before being transferred to the potting soil. One hundred seventy two plantlets were successfully acclimatized in green-house and transplanted to the field.