The Analysis In Growth Characteristics And Salt Tolerance Of Transgene Populus Simonii×P. Nigra Clones Carrying TaLEA Gene

A total of 10 transgene and one control Populus simonii×P. nigra lines were used to investigate and analysis the variation of growth curve of tree height and basic diameter, Genetic stability, Photosynthetic indicators of lines under NaHCO3 stress, The result showed that, no matter in greenhouse or in afforestation site,there were remarkable differences in basic diameter of each clone.In four afforestation site (saline-alkali soil), clone XL-1 showed the best growth curve of tree height and basic diameter among 10 lines, was selected as the best lines1. The result showed that tree height and basic diameter growth process curve accord with "S" shape. The coefficients of Logistic model were higher than 0.9 which indicated that the functions of the model were effective. Lines were directly infulunced by growing time, duration of fast growth period. Based on the final growth amount, Clone XL-1 and Clone XL-9 showed the best growth amount in 10 lines, these two lines were higher than CK 16.37% and 10.92% in H growth, respectively, the BD was higher than CK by 32.82% and 22.68% in BDgrowth, respectively, and we select these two lines as the best lines preliminary. The transgene lines of TaLEA showed certain degree decrease in photosynthetic indexes under the stress of NaHCO3, but all diameters’descend range were smaller than CK, XL-1 and XL-10 fall less than the other lines, so select these two lines as the best salt--resisting lines.2. After investigation and analysis of H and DBH of 2 years transgene lines of TaLEA in 4 affrestation sites, the result showed:among 4 afforestation site, clone XL-1 showed the best growth, select XL-1 as the best salt--resisting lines. In greenhouse, all lines’phenotypic variation coefficient in H and DBH were 19.33%and 25.16%, respectively. After afforestation, all lines’Phenotypic variation coefficient in H and DBH were 20.99% and 41.22%, respectively, repeatability were ranged from 0.772 to 0.965, hign variation and high repeatability means lines were less affected by environmental factors, which is good for the selection of best lines. The result of Genetic stability analysis showed:different lines showed different adaptability in different sites. XL-1 and XL-9 had the best growth in H and DBH in four sites, although these two lines have abad stability, but the growth character were good, they may be confirmed as the best lines after further investigation.3. A total of 10 Populus simonii× P. nigra lines (10 transgenic poplar lines and one control clone) in Daqing were used as materials and 15 traits which included growth traits, shape of stem, leaf traits, lenticel traits were investigated and analysesed. ANOVA analysis results showed that there existed remarkable difference in all the investigated traits among 10 lines (P<0.01), each character’s phenotypic variation coefficient was 1.92%(DBH skin depth)-39.98%(lenticel traits), genetic coefficient of variation was 0.84%(DBH skin depth)-33.42%(lenticel traits); repeatability was higher than 0.6. Using the comprehensive Evaluation, select by 20%, XL-1 and XL-9 was selected as the best lines, which the H and DBH was higher than CK by 16.55% and 15.38%, respectively. The genetic gain of H and DBH were 12.18% and 17.42%, respectively.4. Measuring the photosynthetic indexes and chlorophyll fluorescence parameters of transgene TaLEA lines which were under the stress of NaHCO3, the results indicate that with the increase of concentrationthe, Pn、GS、Tr、Ci and Fv/Fm were all decreasing.The decrease showed transgene lines were influenced significantly. The falling range of all transgene lines was smaller than CK. The best lines were XL-1, XL-10, XL-9, which means the TaLEA raise the resistantAll in all, in the process of genetically modified, because of the difference of Gene insertion sites or copies, there are differences of genetic expression and metabolism ends in the difference of phenotype, physiology and resistance. The XL-1 and XL-9 was better than the other lines in the growth of seeding stage and resistance, can be focused as the best lines.Work of next steps was doing the follow-up growth survey of different lines in different sites, providing basis of selction of best lines in different sites.