Construction And Evaluation Of Core Collections Of Momordica Charantia

Momordica charantia belongs to a cucurbitaceous momordica plant. It already has cultivation history of several hundred years and formed abundant genetic diversity. These characters provide abundant raw materials for breeding good stock, and at the same time, it also causes many problems to storage, utilization and evaluation of core collection. Therefore, it is urgent to carry out establishment and evaluation study on core collection of bitter gourd, in order to provide theoretical basis for the preservation and utilization of desirable traits of fine collection resources. Combined with analysis on genetic diversity, morphological markers and molecular markers are respectively used in this study and 71 samples are selected from 244 materials of bitter gourd to form core collection of bitter gourd. The main conclusion is as follows:1. According to 224 materials of bitter gourd, Bitter with 22 morphological characters based on the data collected with fruit shape as the classification standard,24 sampling schemes are compared. Through comparing 4 important evaluation parameters of each scheme, the optimal scheme selected is that:under 20% of overall sampling scale, the sampling is carried out within group by using gradual clustering methodology according to logarithmic scale, to form core collection preselected, and then by comparing every characteristic of original collection and supplementing lost characters, Primaries core collection of bitter gourd containing 50 materials and based on morphology data is confirmed finally.2. To optimized the SSR-PCR reaction system of Momordica charantia, an orthogonal experiment design of L16(45) with four levels and five factors was carried out, the factors were the concentration of Mg2+, the concentration of dNTPs, Taq polymerase, DNA temple and the concentration of prime. According to the result of the orthogonal test, And we determined the concentration of Mg2+, the concentration of dNTPs and DNA polymerase using single factor experiment design. The results showed that the optimum system containing 1μL 10×PCR buffer,Mg2+ 1.75 mmol/L, dNTPs 0.25mmol/L, Taq DNA polymerase 1U, DNA temple 100 ng, prime 0.20 mmol/L, enough ddH2O to eke out 10μL reaction liquid.3. By using genome DNA of 18 bitter gourd collections with greater difference in phenotypic character,13 pairs are selected from 120 pairs of universal primers of cucurbits and specific primers of bitter gourd for population diversity analysis.89 bands are amplified from 13 pairs of SSR primers with polymorphism, of which 73 bands are of. polymorphism and polymorphic bands accounts for 82.02%.4. Use 13 pairs of SSR primers to amplify the population; "1" and "0" database matrix is established by using amplified results, which is used to carry out cluster compression to bitter gourd collection. The results show that under the compression ratio of 30%, genetic diversity of the original population can be retained at the greatest degree and core collection of bitter gourd containing 73 copies of materials and based on molecular data can be obtained.5. Integrate collection bank based on molecular and morphological data; carry out cluster compression to it again by making use of molecular and morphological data; the result shows that optimal proportion for compression of collection resources integrated is 90% and finally,71 materials of core collection of bitter gourd have been obtained.