GsWRKY57B Gene Genetic Transformation Of Tobacco And Soybean

Salinity, drought and other adverve conditions, which seriously restrict theagricultural production in China, are the important limiting factors for plant growthand development. Soybean is one of the main crops in the northeast of China. However,soybean production does not satisfy the demand of the increasing populationworldwide. Improving soybean yield by cultivating transgenic soybeans, which willmake full use of land resources, is of great significance.Recently, more and more studies showed that WRKY transcription factors werebroadly involved in plant response to biotic and abiotic stresses. The present studyfocuses on functional analysis of a WRKY transcription factor, GsWRKY57B, whichhas potential roles for improving plant tolerance to unfavorable environments andimproving yield, by an Agrobacterium-mediated gene transfor method into tobaccoand soybean plants.The main results were as follows:1. Agrobacterium-mediated transformation of tobacco plants(1) Construction of the expression vector pBEOM-GsWRKY57B.(2) Screening of transgenic tobacco plants by PPT.Attach leaf blade under different concentrations of PPT induction culture medium androoting medium. The concentrations of induction culture medium and rooting mediumwere1.1mg/L and1.3mg/L respectively.(3) Genetic transformation of tobaccoTobacco leaf was used as explant, infected for5min, co-cultivated for3d. Thenthe explants were transferred to the medium containing1.1mg/L PPT and500mg/Lcefotaxime. After resistant shoots were developed, buds were cut and placed in therooting medium with concentration at1.3mg/L.53out of60explants weredifferentiated, and a total of85seedlings were generated. After rooting process, a totalof37seedlings were generated. By PCR detection,26plants were identified as positiveones. The transgenic rate was30.6%. 2. Phenotypic analysis of transgenic tobaccoBoth the leaves and seeds of transgenic tobacco plants were showed to be more tolerant to salt and drought stresses than wild type plants.3. Establishment of an Agrobacterium-mediated genetic system for soybeanSoybean culture medium used in this study:Soybean seeds sprouting medium: B5+0.5mg/L6-BA; pH:5.8. Co-cultivation medium:1/10B5+3.9mg/L MES+1.67mg/L6-BA+40mg/L AS+0.25mg/L GA3+400mg/L L-cys; pH:5.4. Screening medium:B5+0.59mg/L MES+1.67mg/L6-BA+500mg/L Cef+5mg/L ppt; pH:5.7. Elongation medium: B5+0.59mg/L MES+50mg/L Pyr+50mg/L Asp+0.5mg/L GA3+0.1mg/L IAA+1.0mg/L ZT+2.5mg/L ppt; pH:5.6. Rooting medium: MS+2%sucrose; pH:5.7.Soybean seeds were sprout for4-5d, infected for30min, and then co-cultivated for3d. The explants were transferred to the screening medium containing5.0mg/L PPT. In elongation medium, PPT concentration is2.5mg/L. The buds were cut and placed into IBA solution for1min when the lenth was3-5cm. Then the explants were transferred to the rooting medium. A total of100explants were used, and only one seedling was obtained and identified as positive one by PCR detection. The transgenic rate was1.0%.