| Agrobacterium-mediated transformation and SAAT (Sonication-assistedAgnobacterium-mediated transformation) were adopted to introduce the salt-tolerant geneAtNHX1 and coda into Berkeley and Bluecrop, which are two cultivars of blueberry. Andnew salt-tolerant transgenetic plants of blueberry were obtained. The detailed results wereas follows:1. The two northern highbush blueberries and one rabbiteye blueberry were studied.To develop new methods for tissue culture in different blueberry cultivars. The explantsused for culture were juvenile stem segments excised from mature trees in orchard. Aftersterilizing, these explants were cultured on modified 1/2MS medium containing differentplant hormones. The optimal culture medium and condition were selected. The resultshowed that multiple shoots formation from the explants of Powderblue, which is onecultivar of the rabbiteye blueberries, were induced on modified 1/2MS medium withZT3mg·L-1. The survival rate was 100% and the multiplication coefficient were 2.8 after 4weeks. Both Berkeley and Bluecrop belong to northern highbush blueberries, were inducedon modified 1/2MS medium with 2-ip 10,5mg·L-1, respectively. The survival rates ofBerkeley and Bluecrop were 90% and 86.7% with the same medium. Four weeks later, themultiplication coefficient were 6.2 and 4.8, respectively, cultured on modified 1/2MSmedium+ZT5mg·L-1. Then the micro-shoots were rooted on modified 1/2MS mediumsupplemented IBA 0.1mg·L-1 and the rooting rate was 100% after three months.2. Transgenic plants were generated from leaves of Berkeley and Bluecrop byagrobacterium-mediated transformation. By analyzing the percentages of gus genetransient expression and bud regeneration rate, we selected the optimum parameters of thistransformation system. The results showed that the highest percentage of gus gene transientexpression could be realized under the following condition, namely explants being dippedinto agrobacterium suspension for 5 minutes, 4 days of co-cultivation on modified 1/2MSwith AS80mg·L-1, Km20mg·L-1 and Cef 250mg·L-1. The dark-clutivation time of Berkelryand Bluecrop were 1 week and 3 weeks, respectively. 3. By studying the effects of different power and time of the ultrasonication on SAATin blueberry, the results showed that the percentages of gus gene transient expression was55%, bud regeneration rate was 23.33%, the rate of injury explants was 23.67% whenAtNHX1 gene was transfered into Bluecrop under 80W of the ultrasonication for 2s; codAgene was transfered into Berkeley under 100W of the ultrasonication for 6s, the highest gusgene transient expression was 73.33% , bud regeneration rate was 33.08%, the rate ofinjury explants was 22%.4. In this study, by Agrobacterium-mediated transformation and SAAT Km-resistantplants were obtained introducing AtNHX1 gene and codA gene into Berkeley andBluecrop. The rate of resistant shoots of Berkeley and Bluecrop were 6.66% and 2.18%,respectively, when transfering AtNHX1 gene. And the rate of resistant shoots of Berkeleyand Bluecrop introducing codA gene were 4.24% and 3.18%, respectively. Berkeley withcodA gene obtained the highest GUS positive rate, was 33.33%. PCR and histochemistryGUS assay on these resistant plants approved that the target genes were integrated into thehost genome of blueberry.
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