| The common dandelion is a perennial, herbaceous plant which has a widespread distribution. More and more attention is paid to it for its abundant nutrition, good medical actions and evident use in health care. In order to satisfy people's potential demand of daily life, regeneration system of sterile leaf and sterile root of dandelion were studied. A preliminary study of anther culture was also done. Our test results are as follows:1. MS medium with different combination of phytohormones showed significantly different to the regeneration of leaf. MS medium containing 0.2mg/L NAA and 1mg/L 6-BA or MS medium containing 0.2mg/L NAA 2mg/L 6-BA were the best of all. Frequence of shoots formation of the best medium was 100%, and there were 12 shoots per explant of the best medium. There were no significant between B5 and MS medium on regeneration of leaf. The best times of the leaf culture cycle was 60d. The leaf culture cycle would lasted to 90d and total propagation coefficient was 560 after the culture of shoot propagation. Percentage of shoots rooted was above 90% after plantlet rooted on MS medium.2. 10d after leaf inoculated, Effect of NAA concentration(0.2～2mg/L) on frequence of shoots formation was significantly different at P＜0.01, BA concentration(0.5～5.0mg/L) was significantly different at P＜0.05 and interaction of two phytohormones was significantly different at P＜0.01. 20d and 30d after leaf inoculated, NAA concentration on frequence of shoots formation was significantly different at P＜0.01, BA concentration and interaction were not significant. 10d after culture, NAA concentration on number of shoots per explant was significantly different at P＜0.01, BA concentration and interaction were not significant. 20d and 30d after culture, NAA and BA concentration on number of shoots per explant were significantly different at P＜0.01, interaction were not significant.3. According to the correlation analysis of leaf regeneration we got the following conclusion: NAA concentration(0.2～2mg/L) had Negative correlation with frequence of shoots formation and number of shoots per explant, and correlation was significant at P＜0.01. Correlation between NAA concentration with frequence of shoots formation and number of shoots per explant was higher than that of BA concentration(0.5～5.0mg/L). Hight of shoots per explant had Negative correlation with NAA and BA concentration, and hight of shoots per explant reduced while concentration of two phytohormones increased. 4. According to the regression analysis of leaf regeneration we got the following conclusion: Frequence of shoots formation had negative correlation with NAA concentration and square of BA concentration; it also had positive correlation with interaction of NAA and BA concentration. Number of shoots per explant had negative correlation with NAA and square of BA concentration; it had positive correlation with square of NAA, BA concentration and interaction of NAA and BA concentration.5. MS medium with different combination of phytohormones was significantly different to the regeneration of root. MS medium supplemented BA (0.2, 0.5mg/L) were the best of all. Frequence of shoots formation of the best medium was 93%, and there were 5 shoots per explant of the best medium. Effect of MS medium with 6-BA was better than that of MS medium with combination of 6-BA and NAA. Percentage of shoots rooted was above 90% after plantlet rooted on MS medium. Globoid formation first after root inoculated, adventitious shoot formation later. There was no globoid formation when medium supplemented NAA. Globoid formation had some relation with shoot formation according to paraffin slice of globoid.6. Different BA concentration significantly influenced root regeneration. 50d after root inoculated, medium with BA (0.2, 0.5mg/L) had a significantly higher frequence of shoots formation than that of medium with BA (1.0 mg/L). Medium with BA (0.2, 0.5mg/L) also had a significantly higher number of shoots per explant than that of medium with BA (0, 1.0mg/L). NAA, BA concentration and interaction of the two phytohormones significantly influenced frequence of shoots formation and number of shoots per explant.7. According to the correlation analysis of root regeneration we got the following conclusion: NAA concentration(0.2～2mg/L) had Negative correlation with frequence of shoots formation and number of shoots per explant, and correlation was significant at P＜0.01. BA concentration(0.5～5.0mg/L) had Negative correlation with frequence of shoots formation and number of shoots per explant, but correlation was not significant. Correlation between BA concentration with frequence of shoots formation and number of shoots per explant was higher than that of BA concentration.8. According to the regression analysis of leaf regeneration we got the following conclusion: Number of shoots per explant had negative correlation with NAA concentration and square of BA concentration; it had positive correlation with BA concentration, square of NAA concentration and interaction of NAA and BA concentration.9. One-step plantlet development succeeded though root regeneration on MS medium. This procedure is of significant importance to reduce variation and to keep dandelion's quality stabilization.In addition, there is a preliminary study on anther culture of dandelion. Plantlets through callus formation were abtained, ploidy levels testing showed no haploid plantlets by flow cytometric studies and chromosome counting.
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