Variation Analysis Of Physiology Traits In Transfer Lea-bZIP Gene Of Betula Platyphylla Under Salt Stress

In this study, the lea/bZIP divalent gene, which were cloned from extremely drought and salt-tolerant tamarix chinensis, was transformed into Betula platyphylla, then the salt-stress experiments of transgenic and non-transgenic of B. platyphylla lines were conducted. The results were shown as follows:1Five kanamycin resistant lines were obtained and all of them showed positive by PCR detection which indicated that lea/bZIP divalent gene were integrated into the B. platyphylla genome perfectly. Three of transgenosis lines were selected to conducted Northern blotting hybridization, the results showed that the lea/bZIP gene were expressed on RNA level which provide materials for the next step research.2Wild type birch were selected to be material for different salt concentration stress experiments. Base on endured time investigated and phenotype observed,0.4%concentration of salt were choosed for the most appropriate concentration for salt tolerate experiments.3Photosynthesis indexes and chlorophyll fluorescence parameters were showed decline trend with salt concentration increased, but the photosynthesis indexes of lines L-4and L-8were higher than CK which indicated that both of these two lines had higher ability on salt tolerance.4On the condition of salt stress, the photosynthetic indexes and chlorophyll fluorescence parameters reduced the earliest for the bottom leave in the same plant, then the upper, Na+analysis results indicated that the forwarding process of Na+were from bottom to upper.5On the condition of salt stress, the antioxidant enzyme system indexes (POD and SOD) showed first increased and then decreased trend, but MDA increased with time prolongate, which indicated that on the minor salt stress, the antioxidant enzyme system can defensed stress by autogenous regulation, but with the stress aggravated, the plant damaged seriously, and result in death ultimately.6There were also exist difference between different lines on the research of Pn-Par and Pn-Ca curve. Under normal operation, Pn of all the lines were increased with Par increased, but lines L-4and L-8showed higher Pn than lines CK and L-5in the same Par intensity. On the salt stress condition, L-4and L-8were also showed higher Pn with Par increased than CK and L-5which indicated that the transgenosis can affect the photosynthesis of plant, but the plant can express different because of the different insertion site of gene.Growth traits, photosynthetic traits, chlorophyll fluorescence characteristics and Na+contents were investigated to dicuss the salt tolerance response on transgenosis birch, which showed important values. Lines L-4and L-8expressed much more outstanding in many traits than lines L-5and CK, which indicated there were certainly influenced by transfer new genes into plants. Gene expression process, gene expression regulatory network, variation of protein and metabolic process should be investagate in the next step which can understand the function of transfer gene deeply.