Changes Of Physiology And Biochemistry In The Course Of In Vitro Flowering Of Cymbidium Kanran Makino

In this paper, the test-tube seedlings of Cymbidium kanran Makino were used asexperimental material to study the dynamics changes of carbohydrate, protein,isoenzyme and nucleic acid contents in the course of in vitro flowering. The resultswere as followings.There are closely relationship between the carbohydrate content and in vitroflowering. The flowering was promoted by the accumulation of nutritive material.The contents of soluble total saccharine, sucrose and fructose increased from 0d to40d. They reached their peak value at 40d, 21.4μg/g.FW, 2.90μg/g.FW and 5.1μg/g.FW respectively, while declined after 40d. Metabolism and transport of starch hasrelationship with flowering too. Starch content gradually increased from 0d to 20dwith reaching the highest value of 7.1μg/g.FW, while decreased to the lowest valueof 2.1μg/g.FW from 20d to 50d, rose to 4.6μg/g.FW from 50d to 80d. Proteinmetabolism was related to the process of flower formation. The content of solubleprotein declined from 0d to 20d, but rapidly rose to its peak value of 2.90mg/g.FWfrom 20d to 50d, then drop after that. Insoluble protein increased to the highest valueof 1.78 mg/g.FW from 0d to 30d. The content of total protein had no obvious changefrom 0d to 20d, but increased to its peak point of 4.6mg/g.FW from 20d to 50d,rapidly decreased to the lowest point of 4.0mg/g.FW at 70d. Nucleic acid metabolismprepared for in vitro flowering. The content of DNA increased by 8% from 20d to 30d,while the content of RNA and the ratio of RNA/DNA reached to its peak point of6.56mg/g.FW and 15.3 from 0d to 40d, which were 10d earlier than that of solubleprotein, dropt after 40d. Two new soluble protein bands, 16kD at 20d and 65kD at40d, were detected in SDS-PAGE pattern. They were special proteins in the course offlowering bud induction. POD and EST had relationship with the process offlowering bud forming. POD3 and POD4 only appeared from 20d to 50d, POD6disappeared from 60d to 80d, EST4 weakened at 80d, and EST5 weakened from 60dto 80d. The relationship between CAT and MDH and in vitro flowering was not obvious.