Research On The Effects Of Ionic Liquids In The Seedlings Growth And Development Of Pakchoi Cabbage

Ionic Liquids(ILs) are liquids when they are at room temperature or so, which all made of the ionic substances, also known as room temperature ILs, room temperature molten salt or organic ILs. ILs have good physical and chemical properties, and it has been widely used. However, studies show that ILs can be toxic to the organism. The toxicity of ILs on the pakchoi cabbage has not been reported. This paper has researched the effects of the different alkyl chain length and different concentrations of ILs on the pakchoi cabbage seed germination and seedlings growth.The main research results include the following seven parts:(1) Effects of ILs on the pakchoi cabbage seed germination and seedling growth:low concentration (100 mg/L,200 mg/L) of the ILs ([C3mim] BF4) has no obvious effect on seed germination.When the concentration of [C3mim] BF4 is 300 mg/L, the seed germination and seedling growth are obstruced.Compared with the analysis of different carbon alkyl chain length of the influence of the toxicity of ILs, this paper finds that the increasing alkyl chain length can have obvious inhibitory effect on the pakchoi cabbage seed germination rate and growth.(2) Effects of different concentrations of ILs of pakchoi cabbage seedling physiological indices:with the increasing of the ILs ([C3mim] BF4) concentration up to 500 mg/L, the super oxygen free radical content of the processed pakchoi cabbage leaves, hydrogen peroxide content, proline content, malondialdehyde content have significantly increased, at the same time chlorophyll content decreased.At five concentration ILs culture (100 mg/L,200 mg/L,300 mg/L,400 mg/L,500 mg/L), SOD, CAT, APX, GR activity of the pakchoi cabbage seedlings will increase first and then decrease later as the increasing of the concentration. This shows that low concentration of ILs has activate effects on pakchoi cabbage leaf oxidase activity while high concentration has inhibitory effects.(3) Effects of different alkyl chain length of ILs of pakchoi cabbage seedlings physiological indicators:the length of the ILs handling the super oxygen free radicals in pakchoi cabbage seedling period, the content of hydrogen peroxide and proline, malondialdehyde content have increased significantly with the increase of ILs alkyl chain length up to 5 C,6 C, while the chlorophyll content has decreased.the ILs carbon alkyl chain length can also affect the activity of protective enzyme. When carbon alkyl chain length is in 4 C,5 C,6 C, SOD, CAT, APX, DHAR activity of the pakchoi cabbage leaf is significantly lower than the control group. The above result shows that the longer the alkyl chain is, the greater the ILs carbon’s enzyme inhibition effects on the pakchoi cabbage seedlings. This shows that the longer the alkyl chain length of the ILs is, the greater the damages to cabbage seedlings.(4) Effects of treatment duration of ILs of pakchoi cabbage seedlings antioxidant enzyme genes and DNA mismatch repair:when the pakchoi cabbage is processed longer in the 400 mg/L of ILs [C3mim] BF4, the gene expression of APX, SOD and CAT of pakchoi cabbage leaf will reduce. That is to say longer process to pakchoi cabbage PCNA1, PCNA2, MSH2, MSH7 gene expression. will reduce. Therefore, the longer pakchoi cabbage seedlings grow in ILs, the more damages to its growth.(5) Effects of different alkyl chain length of ILs of pakchoi cabbage seedlings antioxidant enzyme genes and DNA mismatch repair:after the pakchoi cabbages are cultivated 13 days seperately under the same concentration of 200 mg/L [C2min]BF4, [C3mim]BF4, [C4mim]AC, [C5mim]BF4, [C6mim]BF4, four main findings are concluded. Firstly, gene expression of CAT, APX and SOD all decrease. Secondly, as the growth of the ILs alkyl chain length, CAT and APX gene expression decrease first and increase later. Thirdly, SOD gene expression decrease with the ILs alkyl chain length increases. At last, gene expression of PCNA1, PCNA2, MSH2 MSH7 reduces.Above all, a high concentration of ILs will have an restraining effects on pakchoi cabbage germination and seedling stage growth, which are represented by the reduced protective enzyme, increased reactive oxygen species, the affected oxidation inhibit genes and their DNA mismatch repair related genes. From the data observed from the processed ILs with different alkyl chain length, we can conclude that with the increase of ILs handling time, the greater damages to the growth of pakchoi cabbage.The processing time and increased ILs can lead to pakchoi cabbage DNA damage. And the different structures of anion can have different toxic effects on small plants.