Tissue Culture And Transformation Study In Kentucky Bluegrass(Poa Pratensis L.)

Traditional breeding is difficult to reach the proposed breeding targets in Poa pratensis L.while genetic engineering technology could be efficient to improve some traits. Establishing a efficient tissue culture system is the basis of genetic engineering. In this research,12 Kentucky bluegrass varieties were randomly selected as the materials for the test of callus induction, proliferation and differentiation system with the mature seeds as explants. Each variety showed the callus rate, with 2,4-D added only, from 60% to 93% respectively. The average callus induction rate for 12 varieties reached to the highest of 86% at 3mg/L 2,4-D. When further 6-BA added, each variety showed the callus rate from 30% to 92%, and the average of 12 varieties reduced a little. In the callus proliferation test, the proliferation rate of each variety, with the 2,4-D added only, were in a range of 38%-164%, and the average of 12 varieties reached to the highest of 81% at 3mg/L 2,4-D. Further 6-BA (0.05-0.2mg/L) added could reduce the callus proliferation rate to some extent but there existed variety-specificity. The results also showed that the heat shock had some effect on callus induction and proliferation for some Kentucky bluegrass varieties. In the callus differentiation test, the highest callus differentiation efficiency turned up when 2mg/L 6-BA was added alone. For some varieties, few 2,4-D added could improve the callus differentiation rate.