Research On The Character Separation Characteristic In Inbred Line Of Alfalfa And Its Embryo Rescue System

This study on the self-intersection S1 generation of multifoliate alfalfa, and gives a systematic research on its separation. It not only analyses the multifoliolate expression on leaf, but also illustrates the leaf type of multifoliolate alfalfa and its relative multifoliolate chararter. Meanwhile, as the inbred-fruitfulness of alfalfa is just between 2.2%-6.6%, the experiments takes the MFS5,MFS42 and MFS46 as the reference material. And it's also conducted a research in detail on the abortion rate, the optimal times in the embryo rescue culture and the effect on different levels of hormone in the embryo rescue of alfalfa inbred line . Such findings can provide fundamental basis for the embryo rescue of alfalfa breeding, and come up with the effective method in the aspects such as an effective solution for low seed setting rate of multifoliate alfalfa S1 generation. The main researched are as follows:1.After inbred of the selected multifoliolate single plant, the S1 expresses the multifoliolate. And it's only separated in the leaf type of multifoliolate alfalfa. There are 8 kinds of the separation in the leaf type of multifoliolate alfalfa. The type of 4+5+6+7 have 43 plant,it is the main types。2.There are 6 relative indexed and plant height in the self-intersection S1. Apart from 22.24% of the plant height, the rest 6 indexes'coefficients of variation are above 50%. It's indicated that there is the obvious differentiation in the multifoliolate trait among the inbred line. The colors and plant types in the self-intersection S1 generation of multifoliate alfalfa also separate a lot.3. The total compound leaf multifoliolate rate in S0 is about 86%. After inbred, it's also separated as the 2 between 80%-90%, 54 between 10%-40% respectively. The multifoliolate rate in the single plant of MFS5 reaches at the maximum of 93.35%. After the separation of multifoliolate inbred line, the multifoliolate rate of inbred line is reduced than the parent strain.4.There is a highly correlation between the character of the multifoliolate leaves, and also a certain correlation between the respective character and height. Through the clustering analysis, the 80 single plants in inbred line can be classified into 3 kinds. In MFS5, the highest compound leaf multifoliolate rate single plant is 93.35% while the leaflet multifoliolate rate is 96.33%. The leaf type of the MFS42 single plant is type of 4+5+6+7,in which the 7 leaf are the main types and its compound leaf multifoliolate rate is 58.00% with a clear multifoliolate character. It can be used as the Hybrid breeding parents or Germplasm. The compound leaf multifoliolate rate in MFS46 is 73.46%, with the stable multifoliolate character. It is a fine single plant with appearance of the palmate of Multi-leaf with 4 or 5 leaves, in which 4leaves are more.5.The abortion rate of the pollination in multifoliate alfalfa for 40 days shows that, the average abortion rate after the 3 single plant inbred in the multifoliate alfalfa S1 is 37.59%, and the lowest was 28.84% in the fifth single plant.6. The best way in sterilization for Alfalfa embryo was that: firstly it was processed in alcohol of 70% for 30s and then treated in the 0.1% Hgcl mercury solution for 20 min. It not only can effectively control the contamination and keep the death rate of embryo at a relatively low stage.7. Under the low temperature treatment of Alfalfa embryo, the inductivity in the callus variation trend shows diversity. The time in low temperature treatment of top inductivity ones is 4 days for reserve in subzero 4℃.8. The best time for sampling in embryo rescue culture is 30 days after flowering, the average germination rate in the three plant traits of multifoliate alfalfa S1 generation was 46.71%. The germination rate becomes increasingly high at the inoculation time between 20 days and 30days, and reaches the summit at the 30 days. After the 30days, it begins to descend. The germination rateis lowest as the average is only 12.16% when flowering for 40 days.9. The alfalfa in different types of gene has a direct effect on its inductivity in the callus and the callus growing speed in the growing of subculture medium.10. Establishing optimal system of tissue culture in the embryo rescue culture of the embryo rescue culture for self-intersection S1 generation of multifoliate alfalfa...