The Research On Chemical Mutation In Vitro Of Cymbidium Kanran Makino

Using EMS, DES, colchicines, caffeine, 5-BU, MH, Na₂SO₃ as mutagenic agents, and using the PLBs of Cymbidium kanran Makino as material, we studied the technique of mutagen in vitro. This article researched the effects on growth, proliferation and differentiation of PLBs treated with mutagenic agents, chosed appropriate concentration and time, used technique of morphologic to check up phenotypic mutation, used cytological technique to observe the influences on karyons of root tip, analyzed the physiological and biochemical change of plants from PLBs treated with mutagenic agents, at last, used ISSR-PCR amplified system to analyze the change on genome of plants from PLBs treated with mutagenic agents. The results were as follows:1. Each mutagenic agent could resrain the growth of PLBs, with the increase of concentration and the prolonged time, the brown ratio and death ratio rised, the brown ratio were always less than death ratio.2. Each mutagenic agents could resrain the proliferation of PLBs, with the increase of concentration and the prolonged time, the death ratio rised, the connection between proliferation rate and absolute growth rate were not simple correlativity.3. Analyzing the results, we calculated the LD50 on PLBs of mutagenic agents, it related to concentration and time, the results could be the referenced dosage for chemical mutation of Cymbidium kanran Makino.4. Some phenotypic mutation appeared on plants from PLBs treated with mutagenic agents, mostly were flavicant leafs. The distinct phenotypic mutation mostly appeared on the plants treated with EMS and colchicines. The percentage of phenotypic mutation were not high.5. Each mutagenic agent could change karyons of root tip on cytological level, mostly were abnormal karyons phenomena, micronucleus phenomena, multinucleus phenomena, cracked karyons phenomena, concentrated karyoplasms phenomena, chromosome aberrance phenomenon(double, lag, deletion).6. The soluble sugar content of the plants from PLBs treated with muta- genic agents were higher than normal plants;the soluble protein content of plants from PLBs treated with EMS, DES, colchicines, Na₂SO₃ were higher than normal plants, the soluble protein content of plants from PLBs treated with caffeine, 5-BU, MH were lower than normal plants.7. The soluble protein bands, SOD isozyme bands, EST isozyme bands, CAT isozyme bands and POD isozyme bandsof plants from PLBs treated with 7 mutagenic agents were different from normal plants, existed the phenomenon of absent bands or added bands.8. The ISSR-PCR amplified genome bands of plants from PLBs treated with mutagenie agents were different from normal plants, compared with other mutagenic agents, there distinct differences on genome bands between plants from PLBs treated with EMS, DES, 5-BU and normal plants.