Physiological And Molecular Mechanisms Of Male Sterility In Tobacco K326

Tobacco is an important model plant.In this experiment,different sizes of flower buds of the male sterile line and maintainer line of tobacco K326 at the full flowering stage were used as materials and used as mutual control to observe the differences in flower organ structure and related physiological activities.Illumina Hi Seq high-throughput sequencing technology was used to study the differential expression of transcriptome genes.Differential expression of group genes,and their related morphological,physiological and molecular mechanisms were studied.Through the morphological observation and physiological activity study of its flower organs,the transcriptome level study not only enriches the genetic background of tobacco,but also provides a theoretical basis for mining related male sterility genes and exploring the molecular mechanism of tobacco male sterility.Tobacco male sterility seed production provides scientific basis.The test results are as follows:(1)Through the observation of morphological features and microstructure,it was found that the stamens of the flower organs of the male sterile line began to degenerate in the early stage of development.The pistil of the maintainer line was composed of two carpels.However,the pistil of the sterile line was composed of three carpels.The activities of SOD,POD and CAT in the maintainer line showed a downward trend throughout the period,and the content of MDA showed a trend of first decrease and then increase,while the sterile line SOD,POD,CAT and MDA content showed an upward trend.(2)After filtering the raw sequencing data,92 378 158-118 509 436 clean reads were obtained for comparison and analysis.The Q30 of base sequencing quality values were all greater than 94.The GC content was between 41.90% and 42.46%.7881,19931 and 10984 differentially expressed genes were obtained in small buds,medium buds and large buds respectively,of which the number of down-regulated differentially expressed genes was significantly more than that of up-regulated differentially expressed genes,and they were annotated into three categories: biological process,molecular function and cell component.Moreover the number of differentially expressed genes belonging to molecular function term was the largest in the three periods.KEGG pathway analysis shows that the number of differentially expressed genes in the metabolic pathway(ko01100)is the largest,in small buds,medium buds and large buds,and linoleic acid metabolism(ko00591)is related to the largest number of differentially expressed genes.The transcription factor analysis of the differential genes revealed that the most differentially expressed genes in small buds,medium buds and large buds periods belonged to the transcription factor families such as ERF,MYB,C2H2,NAC,ERKY,and b HLH.The screened differentially expressed genes Ntaq3,Ntaq4,Ntaq5,Ntaq6,Ntaq9,Ntaq10,Ntaq13,Ntaq14,Ntaq15,Ntaq16 were expressed in the maintainer line much higher than in the sterile line,indicating that changes in tobacco fertility can cause abnormal expression of these genes.