Responses Of Growth And Physiological Characteristic In Brachypodium Distachyon Seedlings Under Cd Stress

Brachypodium distachyon (Bd21) is a temperate grass with small stature, selffertility, short lifecycle, simple growth requirements, and small genome size. Toinvestigate the effect of Cd stress on growth, inorganic ions and physiologicalcharacteristic of Brachypodium distachyon, we treated Bd21seedlings with variousconcentration of CdSO4(0,50,100,150,200and300μmol/L), and treated theseedlings after waiting for seed germination16d. Then irrigated the seedlings for15d,and sample the leaves for test. It was carried out to investigate the effect of cadmiumon Chlorophyll, protein content, MDA content, antioxidant enzymes expression andmain Inorganic ions contents in the Bd21’s leaves. The major resultes are summarizedas follows:(1) With the CdSO4concentration increasing, the seedling of Bd21’s Na+contentwas increase, K+content was reduced. When the cadmium concentration arrived at300μmol/L, the content of Na+was increased by5.07%, but K+was decreased by15.34%, both compared with control. Ca2+content was increased under Cd stress, itmainly induced to accumulate and participate in resistance in the seedlings under Cdstress. Along with the Cd stress increase, Mg2+and Si4+content were decrease in theleaves, but S2-was increase. The accumulation of Cd itself was increased.(2) The growth and Chlorophyll content of Bd21seedlings were significantlyinhibited by Cd stress. As compared with control, when Cd concentration reached50μmol/L, the Chla、Chlb、Chla+b were more than control, but dropped after100μmol/L. At the same time, the content of water was also decreased.(3) The protein content of Brachypodium distachyon seedlings decreased as Cdconcentration increased. It is found that the protein content was negatively-related toCd concentration. But when the cadmium concentration arrived at50μmol/L, thecontent of protein content was increased by12.99%.(4) Brachypodium distachyon seedlings were induced membrane lipid peroxidationby Cd, with the higher concentrations of Cd stress could enhance lipid per oxidation, destroy protection ability and enhance MDA content.(5) The effect of Cd on CAT and SOD activities were similar in the seedlings ofBrachypodium distachyon. The enzyme activites were inhibited in higherconcentrations. With different concentration of Cd treatment, POD activities wereincreased.