SOMATIC EMBRYOGENESIS AND PLANT REGENERATION FROM COTYLEDONS OF IMMATURE EMBRYO OF CHINESE JUJUBE (ZIZYPHUS JUJUBE MILL.)

Chinese jujube somatic embryogenesis and plant regeneration from immature cotyledons were achieved for Chinese jujube (Zizyphus jujube Mill.). Open-pollinated fruits were collected from trees 40-70 days after full-blooming in the field. The cotyledons were transversely excised in the middle and the proximal half was placed abaxial side down on the medium. The effects of different concentrations of thidiazuron (TDZ), indole-3-acetic acid (IAA), sucrose, MS (Murashige and Skoog, 1962) medium and the presence or absence of light for culture were determined. The optimal somatic embryogenesis rate was obtained on 1/2 MS medium containing TDZ 0.4 mg/L, IAA 0.2 mg/L, and sucrose 20 g/L, followed by maintaining in darkness for the first 30 days. Somatic embryos were then transferred onto the MS medium containing different concentrations of different auxins and 62.41% germination rate was obtained with the 2,4-D (0.001 mg/L), and then 31.25% plantlets were achieved on the same medium.