| Alfalfa (Medicago sativa L.) become an important resource of protein feed, because of its a variety of protein and high protein content. Alfalfa leaf spot caused by Pseudopeziza medicaginis is one of the major diseases of alfalfa industry, after the plant susceptible causing alfalfa production, quality decline, coumestrol seriously affect the digestibility of livestock, livestock breeding females reduced force. Therefore, it is very important to study the infection mechanism of P.medicaginis to control the disease and to realize the sustainable development of alfalfa industry.The field condition, pathogen identification, resistant variety screening, cytology and ISSR of Alfalfa resistance genes have been carried out in the previous studies. But the proteomics research has few reports. In order to resolve the infection mechanism of P.medicaginis from the perspective of protein the study of pathogenesis. In this paper, P.medicaginis infected alfalfa leaves differentially expressed proteins were preliminary studied,the results are as follows:(1) Field investigation showed that:the planting years had a impact on the occurrence and the epidemic of alfalfa spot disease and the severity of the disease. Along with the growth of the planting fixed number of year, the incidence of brown spot disease in alfalfa field was increased Photosynthesis study shows that the health of leaf photosynthetic rate and stomatal conductance is four times that of infected leaves, transpiration rate of health is 2 times of infected leaves.(2) Study on the effect of P.medicaginis infection on the redox system of leaves showed that: alfalfa after infection, the activity of REDOX enzymes and the content of intracellular reactive oxygen species and MDAare changed, made the function of the REDOX system enhanced. It is to say that the infection of alfalfa leaf spot make the disease resistance activity of alfalfa leaves enhanced.(3) Study on the effect of P.medicaginis infection on the differentially expressed proteins in leaves found that:between alfalfa infected with12h,24h,36h and healthy leaves, there are total 57 differences in protein spots were authenticated, including 33 up-regulation protein spots and 24 down-regulation protein spots. From NCBI-Medicago sativa database, we successfully indentified 28 protein spots, and 21 protein spots were successfully indentified from NCBI-Helotiales database. Identification of successful differential proteins are mainly involved in the photosynthesis of alfalfa, the reactive oxygen removal, energy metabolism, the tricarboxylic acid cycle, and so on process. The result shows that, the infection of P.medicaginis effected the photosynthesis and the REDOX system of alfalfa leaves by the different degree. |
