Physiological And Proteome Response To Cd Stress Of Vicia Faba Roots Chronically Polluted By Different Concentration Of Cd Pollution

It's still hot spot to evaluate the ability of plants to adapt to the environment under chronic pollution stress,to explain their response mechanism and the ecological cost.In this research,broadbean(Vicia faba L,Variety ID:K0502),which were generated in different concentration's chronic polluted environment(CK,Cd 1mg/kg,Cd 60mg/kg,Cd 20mg/kg+Pb 60mg/kg)for 15 years,were measured in solution culture with 3 stress level(10mg/L,25mg/L,50mg/L).Among all the seedlings,the quantitative traits,the physiological indexes and their dynamic were measured,and the proteome data was anylyzed to explore the response difference to Cd stress.The main conclusions could be drawn as follow:(1)Generally,the plants without chronic pollution(CK)showed higher vigor than the others under the condition without Cd stress.However under the condition of Cd stress,the plants from chronic pollution conditions showed higher vigor than CK group,and the plants with only Cd pollution in their history grew better than ones with pollution history of complex of Cd and Pb.(2)Antioxidant system was mainly used to resist heavy metal stress by normal plants(CK).And in the condition of 25mg/L Cd stress,the CAT vigor of CK was up to(142.61±19.93)U/g,which was significantly higher than others from chronic pollution.The result at proteome level also showed a plurality of oxidoreductase differentially expressed between the CK group and the others.(3)Plants with only Cd chronic pollution in history(Cd 10,Cd 60)showed ability to fix energy effectively,flexible adjustment ability of SOD vigor,higher CAT vigor,and could accumulate more concentration of GSH and PRO,maintaining good growth vigor at the same time,which showed good adaptability to Cd stress.But the group with lower pollution history(Cd 10)showed great variation within the group especially at the index of SOD,root vigor and PRO content.(4)The composite group(Com)showed higher growth vigor than that of normal plants(CK)in the new conditions.But its antioxidant vigor and growth vigor was lower than the plants with only Cd chronic pollution in history(Cd 10,Cd 60).At the same time,the composite pollution group tends to use GSH,PRO,glutathione and other secondary metabolites to response to the Cd stress on the environment.This study provided a new uniform stress conditions to test how plants from different chronic pollution environment response to cadmium pollution at physiological level and proteome level.We analyzed the expression of candidate functional protein showing significant difference in energy metabolism and secondary metabolism process.The results of this study make the supplement to explain the response mechanism of Vicia faba to Cd stress,also,at the same time,providing new clues for the micro-evolutionary of population under heavy metal pollution conditions.