Screening Of La-Resistance And La-sensitive Mutants Of Arabidopsis

Arabidopsis thaliana is a model plant, the genetic resources are carried out the development and useness vigorously in Different areas of biology. Many Arabidopsis mutants has been widely used in plant development and study of metabolic pathways. Screening of Arabidopsis mutants has become the premise which study of many important theoretical issues. Arabidopsis in the use of rare-earth work of Agricultural research is few. The anti-Arabidopsis mutant screening study in rare-earth is elemented now. However, resistant plants have not found yet. And screening studies on the rare-earth-sensitive mutant have not started yet.Application of rare earth elements in agriculture widespread increasingly, with the promotion of rare earth fertilizer, speed up enrichment and accumulation of rare earth elements in the soil and environment. Heavy metals as a result of rare earth, Rare-earth into the soil and environment effected the ecological environment and human health, has caused widespread concern in the community. At present, after the cumulative of the rare earth on the farm in the soil impact of the ecological environment has been achieved certain results. But, the role of rare earth on the mechanism of plants is not the system.This test attempts to screen out anti-La mutant of Arabidopsis thaliana and Arabidopsis La-sensitive mutant,for La Resistance and the sensitivity of the material provide a basis for gene mapping. Study the Arabidopsis mutant of anti-La and La-sensitive mutant will explain the genetic effects clearly about the accumulation of rare earth in the genetic point of view, fill the gaps in research of Rare-earth and improve the agricultural environment of rare earth safety evaluation system. As a result of La3 + and other anionic role complex precipitation easily, reduces the effective concentration of La in the medium. At the same time, makes La distribute uneven, these are not in favor of select Mutant,so we explore the conditions of screening.Then established the medium of pure la as Select medium. In order to ensure the medium of pure la homogeneity, to avoid precipitation,regulate Ph 5.5.In the screening experiment, seeds of Arabidopsis thaliana can germinate in the Medium of pure la which concentration is 20mg/kg,but the root can not be grow normally,unable to screening and training.So we select the screening methods to which bending the growth of the root geotropism as mutation indicators.Pressure test in screening,the more La3+ content the more soft-medium. Because of complementary roles of agar medium dosage and the pH value in the effect of medium solidification. To be the right coagulation effect in pH5.5 , when screening resistant mutant,select agar concentration 10g/L.The experimental results show that Arabidopsis thaliana can grow but inhibited in 7-13mg/kg La3+ concentration medium.When concentration greater than 14mg/kg Arabidopsis thaliana are not able to grow.So we select pH 5.5,agar concentration 10g/L, La3+ concentration 14mg/kg as the most appropriate selection pressure about resistance.When screening sensitive mutants increase the concentration of agar to 6g/L. The experimental results show that Arabidopsis thaliana can grow normally in 1-3mg/kg La3+ concentration medium. When concentration greater than 4mg/kg ,part of Arabidopsis thaliana are not able to grow completely and normally. So we select pH 5.5,agar concentration 6g/L, La3+ concentration 4mg/kg as the most appropriate selection pressure about sensitivity.Screening T-DNA mutant seeds 605 group about 121,000 tablets, screening them show that there are about 12 resistant mutants uncertain which keep the root bending,one of the 12 performance specially.Screening EMS mutant seeds 509 group about 60,000 tablets, screening them show that there are about 6 uncertain resistant mutants which keep the root bending.Screening EMS mutant seeds 509 group about 60,000 tablets, screening them show that there are about 3 uncertain sensitive mutants which have no growth, the root does not bend.these may be sensitive mutant plants.10 putative mutants are identified using the previous method, La-resistance and La-sensitivity mutant of stable heredity is not yet discovered.