Preliminary Construction Of Tea Plant Somatic Embryogenesis System (Camellia Sinensis L.)

Somatic embryogenesis(SE)is a plant-specific development process and a key factor for plant regeneration.It is of great significance to the breeding and reproduction of tea plants,and the related genes that control this process are involved in the entire development of somatic embryos.Plays a vital role in the process.However,the research of tea plant somatic embryogenesis has been hindered,and a complete tea plant somatic embryogenesis system has not been established,and its molecular mechanism is still unclear.In this experiment,different tea tree varieties and explants were used as materials to conduct somatic embryo induction experiments,thereby preliminarily constructing the generation system of tea tree somatic embryos.The main results are as follows:1.Tea plant tea seeds induce somatic embryogenesis: using tea seeds of different tea plant species as explants to induce somatic embryos,the best somatic embryo induction rate is Shu Chazao,which is 33.56% at the same age of eight months.In order to obtain a large number of tea tree globular embryos,the cotyledons and growth points of tea seeds are used as explants,and they are cultured in the dark for 4-10 weeks in a medium with different 6-BA and 2,4-D concentration ratios.The results showed that the somatic embryo induction medium of 0.25 mg/L 6-BA and 0.4mg/L 2,4-D had the best induction results.The somatic embryo induction rate at the growth point was 27.6% and the cotyledon was 44.43%..2.Tea tree somatic embryo maturation and adventitious bud development:place the induced globular embryos in a blank medium without any hormones and cultivate in the dark for 4 weeks to obtain a large number of mature embryos.Then the mature embryos were placed in adventitious bud induction medium with different hormone concentration ratios for light culture.The results showed that the germination rate was the highest in WPM medium containing 0.1 mg/L2,4-D and 0.5mg/L6-BA.The germination rate is 20%.3.Three genes related to somatic embryogenesis were identified,and the expression of these genes during somatic embryogenesis in tea trees was analyzed by real-time fluorescent quantitative PCR(q RT-PCR).The LEC1,WUS and CLV3 genes are highly expressed in the early stage of tea tree somatic embryo development,indicating that these genes play a key role in the process of somatic embryogenesis.The research on the related genes of tea plant somatic embryogenesis will provide a basis for further elucidating the molecular mechanism of tea plant somatic embryogenesis.In addition,the successful establishment of tea plant somatic embryo regeneration system is expected to provide important theoretical and technical support for the establishment of tea plant genetic transformation system and the cultivation of new varieties.However,there are still problems such as low induction efficiency and low seedling rate,which need to be further optimized.