Studies On Induction And Identification Of Polyploid Phlox Subulata L.

Phlox subulata L. is a perennial herbaceous creeper. Due to the rich flower-colors and longflowering period, its stem is fasciculate with mat-forming. It can be planted in flat land or small slope aslow groundcover plants. Being planted in hanging baskets, used in rock gardens or as cut-flowermaterial, it plays a vital role in garden greening and plant landscape. As a good material of landscaping,Phlox subulata L. deserves further study and fully exploited.Induction, proliferation and rooting and best medium of Phlox subulata L. explants were attainedthrough orthogonal and individual experiments, A plant regeneration system was also established forPhlox subulata L..This experiment adopted double processing method that researches on mutageniceffects of the2kinds of Phlox subulata L. by using different concentrations and different process-timeof colchicine. It mainly focuses on the morphological index observation of the processed plant and theidentification of chromosome counting method. The experiment reaped the tetraploid material of Phloxsubulata L. successfully, further compared the differences between tetraploid and diploid, andconserved the propagation of tetraploid material through outdoor Transplanting and indoor cultivation.The experimental results are as following:1、Exogenous hormone composition and ratio in the culture medium are the most influentialelements of Phlox subulata L. explants’ differentiation and regeneration. The culture medium ofMS+6-BA1.0mg/L+IBA0.05mg/L+GA₃1.0mg/L was suitable for Phlox subulata L. explants’differentiation; the culture medium of MS+6-BA0.5mg/L+IBA0.5mg/L was suitable for stem segmentmultiplication;the culture medium of1/2MS+IBA0.5mg/L was suitable for Phlox subulataL.explants’root.2、From the chromosome configuration identification of the processed regenerative plant, wecould find that double effect was best when colchicine concentration was in50mg/L range with10d.The double success rates were ‘Tamaryuu’83.3%and ‘Pink’86.7%.â‘ We took93strains of Phlox subulata L.‘Tamaryuu’ in total, which were processed for10d.Among them,60strains were confirmed to be doubled. The double success rate was64.5%.39of74strains that were processed for20d, were confirmed to be doubled. The double success rate was52.7%.31of62strains that were processed for30d, were confirmed to be doubled. The double success ratewas50%.We took91strains of Phlox subulata L.‘Pink’ in total, which were processed for10d. Amongthem,62strains were confirmed to be doubled. The double success rate was68.1%.46of69strains thatwere processed for20d, were confirmed to be doubled. The double success rate was66.7%.32of59strains that were processed for30d, were confirmed to be doubled. The double success rate was54.2%.Thus, when the processing time for10d, doubling effect is best.â‘¡When colchicine processing time constant, with the increase in the concentration of colchicine,doubling the success rate of decrease rate of the group within the highest colchicine concentration of50mg/L doubled. It shows that when the Low concentration and short time processing, double rate is high; when theHigh concentration and long time processing, double rate is high low. We could find that double effectwas best when colchicine concentration was in50mg/L range with10d. But different researchmaterials’ double success rate might be different: for ‘Pink’, among229strains,130were doubled，average double of56.8%; while for ‘Tamaryuu’,140out of219strains were doubled，average double of64.0%. It came conclusion that ‘Pink’ was easier to be doubled.