Molecule Detecting Technology Of Important Soilborne Plant Pathogen From Cotton Field

Cotton is the important agricultural products, it is estimated that in the cotton during differentgrowth, from sowing to harvest can suffer from a variety of40the threat of disease including a variety ofsoil spread pathogen attacks. Some important soil spread diseases can cause the seedling disease ofcotton,While the cotton seedling disease is the main harm factor to cotton growth, often cause death ofcotton seedling, even influence of cotton normal growth. Cotton into strains of important period thesoil-borne cotton Verticillium wilt and cotton is more serious harm blight, known as the "cotton cancer".The soil is the soil-borne pathogens bacteria live sites, however, the soil is the base ofmicroorganisms, separate training very difficult. Establish a need not to pathogens separation trainingcan fast detection methods, to the disease detection, diagnosis, and quarantine, disease resistance ofcotton varieties breeding and reasonable layout, have very important sense. In this paper, the soil andplant seeds and the total DNA extraction, with specific primer, through the nested PCR amplificationestablished a set of cotton Verticillium wilt bacteria, cotton blight, cotton damping off, cotton red diseaseand cotton sudden fall corrosion is fast detection technology, can be on the soil and plant seeds, and inthe above pathogens were fast detection, and have a high degree of accuracy and specificity.Four important soil borne pathogens nest’s first round, the second round PCR primers are: thecotton Verticillium wilt leaves type specific primers D1/D2and INTD2f/INTD2r; Cotton Verticilliumwilt leaves the specific type primers ND1/ND2and INTND2f/INTND2r; Cotton red rot diseasespecificity primer53-6F/53-6R and Fm3/Fm4; Cotton blight ITS1/ITS4primers and specific primerFov1/Fov2; Cotton made blight primer ITS1/ITS4and specificity RsW1/RsW2primers.The testing shows that in Soil DNA Isolation kit （MO BIO Laboratories, Inc production） sudies soiltotal DNA extraction, the use of such primer can detect accurately the soil of the above four pathogens,cotton Verticillium wilt leaves to type soil testing for soil pathogens in the lower amount for10²spores/g, the type of cotton Verticillium wilt leaves the lower soil testing for soil bacteria for10²spores/g.;Cotton blight soil testing for soil pathogen in the lower amount for10²spores/g;cotton red rotdisease soil testing for the lower limit of soil bacteria volume density of10²spores/g; Cotton madeblight soil testing for the lower limit of soil pathogen amount for10^-5g density of sclerotia/g, cottonsudden fall ill soil testing for the lower limit of soil pathogen volume density of10²spores/g.With the method of the above four CTAB infection disease total DNA extracted from cotton, withspecific primer for nested PCR amplification, not only can be accurately identified within the plantpathogen, and can also accurately detection show before the disease in plant whether there are pathogens.Based on the above mentioned four kinds of diseases, different period before the root of cotton testingshowed that, in the12to24hours after inoculation, pathogens can be detected from the cotton roots.The test indicated on the seeds, with CTAB method to the four kinds of pathogens were likely to beinfected with the seeds of the total DNA extracted from, through to the seeds in different parts of thedetection, in seed of short hair and kind of shell can be detected the existence of pathogenic bacteria, andcan identify the pathogenic bacteria, but only the seed of corruption disease infected with red, from embryos that tested the existence of pathogenic bacteria.