A study on the callus induction system in 12 Poa pratensis L.varieties

12 Kentucky bluegrass varieties (Poa pratensis L.) were randomly selected as the materials for the test of callus induction and proliferation,taking mature seeds as explants.Varieties showed different rates in forming callus.With 2,4-D only,it varied from 60% to 93%.With 2,4-D at 3mg/L,the average rate of 12 varieties reached to 86%.By adding some 6-BA(0.1-0.2 mg/L)additionally,the rates changed from 30% to 92%,but the average rate was reduced a little.In the callus proliferation test,the proliferation rates were in a range of 38%-164% with only 2,4-D.The average rate reaches to 81% with the treatment of 3 mg/L 2,4-D.Additional 6-BA at 0.05-0.2 mg/L reduced the average proliferation rate,and the reduction was changing by different varieties.The results also showed that the heat shock increased the rate of callus induction and proliferation for some Kentucky bluegrass varieties.