Differential Proteomics Analysis Of Rehmannia Glutinosa Libosch. Under Continuous Cropping

In this study, we used the plotted "Wen 85-5 Rehmannia glutinosa Li bosch"as the experimental material. During the stage of root enlargement, technology of proteomics, physiological and biochemical determination, as well as FTIR and HPLC were used to study the influence of autointoxication on their physiological and biochemical characters,as well as their quality under the continuous cropping. The following is a preliminary analysis on the cause of continuous cropping and the effects on the quality of Rehmannia.Under continuous cropping,the contents of chlorophyll in Rehmannia glutinosa was lower, which led to decreased photosynthetic capacity and root activity.The cumulation of free radicals in Rehmannia glutinosa resulted in enhanced POD,SOD,and CAT activity, and increased content of MDA correspondingly. It was proved that continuous cropping threatened the growth of Rehmannia glutinosa and interfered their normal physiological activity, as a result, the growth of Rehmannia glutinosa was stuntedProteomic analysis showed that 37 proteins performed different expression patterns, out of which 31 proteins had been identified by MALDI-TOF-TOF/MS.The proteins can be divided into six groups, includingâ… :six proteins related to photosynthesis.two of which was rubisco activase,and they both have lower expression in Rehmannia glutinosa under continuous cropping. As a result, they affected the function of Rubisco which was a key enzyme to photosynthesis. Therefore, it was one of the most important factor leading to lower photosynthesis capacity of Rehmannia glutinosa under continuous cropping.â…¡:eight proteins related to photosynthesis metabolism, of which fructose-bisphosphate aldolase, Os04g0234600, malonyl-CoA:ACP transacylase, putative pyridoxine biosynthesis protein isoform A play very important role in biosynthesis of saccharide, lipid and vitamin correspondingly. They all were down-regulated in Rehmannia glutinosa under continuous cropping. ATP-dependent Clp protease ATP-binding subunit clpC homolog and proteasome subunit alpha type 5 are both related to the degradation of protein,taking part in clearing damaged proteins in plant. Putative S-adenosylmethi onine decarboxylase proenzyme joins in the biosynthesis of SAM which is a general donator of methyl.It being up-regulated maybe related to more requirement of SAM in plant.â…¢: four proteins related to energy metabolism, all of which were up-regulated, so it is presumed that Rehmannia glutinosa would encounter stress and need plenty of energy.â…£: Six proteins related to plant resistance,three of which were heatshock protein.Their being up-regulated also indicated that Rehmannia had had encountered stress.As different antioxidase have different response to oxidation stimulus,one of the two antioxidase was down-regulated,and the other was down-regulated first and then up-regulated late.One pathogenesis related protein was down-regulated,which indicated that the disease resistance of Rehmannia under continuous cropping were damaged,so that they could not resist pathogenic bacterium effectively.â…¤:One mRNA binding was down-regulated,which suggested that continuous cropping interfered the expression of genes in Rehmannia,making them function abnormally.â…¥:Two proteins related to cell division.which are putative spindle disassembly related protein CDC48.They might existed in the two different forms,active and unreactive.According to the result of FTIR and HPLC, pharmaceutical products in first cropping Rehmannia glutinosa was more than that under continuous cropping.In a word, continuous cropping had grave damage to Rehmannia.First,it destroyed the roots of Rehmannia,restricted them to absorb water and nutrient,affected their photosynthesis, content of chlorophyll, and expression of key enzymes in biosynthesis, as a result, essential materials could not be supplied enough and secondary metabolism was interfered, what's more ,the biomacromolecule in Rehmannia glutinosa could not function normally, making their resistance systerm confused.At last, Rehmannia glutinosa under continuous cropping could not grow normally and had worse quality.