Studies Of Mutagenesis Technique To Arnebia Euchroma(Royle) Johnst. With Two Kinds Of Herbicides

Arnebia euchroma(Royle) Johnst. was as materials, oryzalin and trifluralin were mutagens, mutagenesis to A. euchroma studied with different methods, such as drop-spreading, shaking, media and other methods. Variability and polyploidy of variant strains from A. euchroma were identified by morphology, porosity, chromosome change and flow cytometry methods. The results were as follows:1. Survival and variation rate of seedlings reached 47% and 60% respectively when they were dot-daubed with 5 mg/L oryzalin, while survival and variation rate of seedlings reached46.1% and 30.7% respectively when they were dot-daubed with 3 mg/L oryzalin.2. Mutagenesis of herbicides to sterile seedlings of A. euchroma treated with shaking.Survival and variation rate as well as stem tip germination rate of seedlings were better than other treatments when the 20 day’s seedling soaked with 1 mg/L oryzalin or trifluralin for 12 h at 20 ℃.3. Survival and variation rates of treated sterile seedlings with oryzalin or trifluralin were 45%, 50% and 36.7%, 26.3% respectively at drop-spreading with cotton-globe. While survival and variation rates of treated sterile seedlings with oryzalin or trifluralin were56.6%,50% and 15%,12.6% respectively at drop-spreading with agar. These showed that the method of drop-spreading with cotton-globe was better than that with agar. Survival and variation rates of treated sterile seedlings with 1mg/L oryzalin were the highest treated with culture method, they reached 45% and 60% respectively. These showed that the method of culture was better than dot-daubed.4. Variability and polyploidy of variant strains from A. euchroma. Change of leaf width of variant strains were obvious than that of leaf length. Stomatic length, guard cell length and width on leaves of variant strains from A. euchroma at field were bigger than that of normal strains. Stomatic densities on leaves of variant strains were lesser than that of normal strains.Guard cell length,width and stomatic length on leaves of variant strains increased obviously compared with the control strains, they reached 32.74%, 19.85% and 90.92% respectively.Stomatic density on leaves of variant strains decreased compared with the control strains, it reached 73.94%. Change of stomatic length(42.66% ~90.92%)on leaves of variant strains treated with oryzalin was bigger significantly than that(63.69%)with trifluralin, so did the change of stomatic density. Chromosome number of the root tip in variant strains from sterile seedlings were 2n = 4x = 28 in the majority. This showed that most variant strains were chimeric plasmids. DNA contents in leaves of variant strains were measured by flow cytometry. This showed that there were diploid and tetraploid in variant strains. Most of them were chimeric plasmids.