Preliminary Study On Innovation Of New Cotton Species With High Oil And Low Gossypol Content

Cotton is an important economic crop. It not only provides fibrous materials forhuman, and the cottonseed also contains rich nutrients such as protein, fat, vitamin,etc.The cottonseed is an important source of plant oil and plant protein. However, thecottonseed contains a small amount of gossypol and its derivatives, which are likely tobreak the gastric mucosa of human and the single stomach animals, causing thedisorder of digestive function.This bother us for a long time from getting betterdevelopment and utilization of cottonseed. But at present,the genetic research ofcottonseed oil content and oil content improvement is still needed. Although we havegotten some low gossypol cotton varieties, but due to its low disease-resistant,thecotton general economical benefits is less than before. So there is important practicalsignificance to develop high oil and low gossypol (plant with high gossypol,cottonseed with low phenol) cotton breeding.In this study we constructed RNAi vector of phosphoenolpyruvate carboxylase(PEPC) and RNAi vector of (+)-δ-cadinene synthetase both driven by cotton seedα-globulin promoter, which can sPEPCifically inhibit the PEPC’s activity and thesynthesis of gossypol of the cottonseed. Thus we can achieve the breeding goals-thecotton with high oil and low gossypol (plant with high gossypol, cottonseed with lowphenol). The main results are as follows:1. We cloned α-globulin promoter of the cotton seed. Compared with thesequence reported, the similarity was99.8%. Construct the dual expression vector ofα-globulin promoter and GUS reporter gene of the cottonseed. Transformed the vectorinto root carcinoma agrobacterium LBA4404by the freezing and thawing method.And obtained the agrobacterium biological engineering bacteria containing the vector,which can be directly applied to transformation. Transformed the vector into tobaccomediated by the agrobacterium, and obtained transgenic plants under PCR detection.we laid a solid foundation in identifying the promoter expression of tissuesPEPCificity and sPEPCificity expression gene engineering of cotton seed.2. We cloned the cotton PEPC gene. Compared with the sequence reported, thesimilarity was95.6%. Constructing the RNAi vector of PEPC gene driven by cottonseed protein α-globulin promoter. Transformed the vector into root carcinomaagrobacterium LBA4404by the freezing and thawing method. Obtained theagrobacterium biological engineering bacteria containing the vector, which can bedirectly applied to transformation. Transformed the vector into cotton callus mediatedby the agrobacterium, and then got the resistant callus induction and embryoids.3. We cloned the (+)-δ-cadinene synthetase gene of cotton. The comparisonshowed that the gene belonged to the family of CDA1-C. Constructed the RNAivector of (+)-δ-cadinene synthetase gene driven by cotton seed protein α-globulinpromoter. Transformed the vector into root carcinoma agrobacterium LBA4404bythe freezing and thawing method. Obtaining the agrobacterium biological engineeringbacteria containing the vector, which can be directly applied to transformation.Transformed the vector into cotton hypocotyl mediated by the agrobacterium, and obtained the resistant callus induction and embryoids.