Somatic Embryogenesis In Dendrobium Candidum Wall Ex Lindl. By Sucrose And ABA

Somatic embryogenesis which is complicated has been an important pathway for studying plant embryogenesis. It is affected by some outer factors such as sucrose, ABA and nitrogen source, and regulated by genes. In this study, the embryonic calli was used as the original materials, which were induced by protocorm-like bodies (PLBs) of Dendrobium candidum Wall ex Lindl. The effect of sucrose and abscisic acid (ABA) were tested on the regulation of somatic embryos of Dendrobium candidum Wall ex Lindl.The embryogenic calli are cultured under the conditions of solid-liquid differentiation medium for 3,4,5,6 weeks, the results indicated that the combination of ABA and sucrose (5% and 6%) were most efficient for the development of embryogenic callus. And with the increase of ABA concentration, embryos development tends to be consistency, growing well, and with the low level of secondary browning. On the other hand, the combination of 6% sucrose and 0.76μmol/L ABA yields the highest level of somatic embryo, the medium of explants unit generated an average of 32 individual embryos, embryo production rate as high as 59%.On the basis of the results obtained above, the total protein pattern was tested with the embryonic callus growth on the solid differentiation medium. We found that after 5 weeks culture the protein expression reaches its peak, and the protein bands are more; The protein content of the treatment of 0.76,μM ABA and sucrose combination is higher than the treatment of 0.57μM ABA and 0.95μM ABA, and there are more small molecule protein bands. Particularly a molecular weight of about 44KDa protein band is strong expression under these treatments.We find that POD and EST enzyme activity outside the training environment with the hormone and changes in sucrose significant changes have taken place. Compared with the control group, the differentiation medium was obtained after somatic embryos POD enzyme deficiency exists more or less with the phenomenon of enzyme, indicating that treatment group Dendrobium somatic embryos decreased respiration; In contrast, treatment EST zymogram group relative control group emerged with a new enzyme, indicating that new gene expression, increase the storage material.Analysis of somatic embryogenesis by regulating the nature of LEC genes and found four kinds of LEC protein, there are totally similar physical and chemical properties, and its functional domain of Bioinformatic analysis found that several genes in plant embryo development plays an an important regulatory role, which LEC1 and L1L genes play a major role in early embryonic development, LEC2 and FUSCA3 genes in embryonic development stages of maturity can control storage protein synthesis and accumulation, and make seeds resistant to desiccation stress capacity.In summary, we believa that 6% sucrose and 0.76μM ABA Dendrobium most beneficial combination of somatic cell production, and storage protein accumulation largest,0.76μM ABA and high concentration of sucrose stress, somatic embryos Dendrobium. In the late globular embryo into the dormant period.