GB/T 31798-2015 in English

1. Background and significance of the standard

GB/T 31798-2015 "Quarantine and identification method of rapeseed black shank pathogen" is to standardize the quarantine and identification of rapeseed black shank pathogen in rapeseed seeds, plants and their products to ensure the safety of agricultural production. This standard is proposed and managed by the National Technical Committee for Plant Quarantine and Standardization.

2. Technical details of the quarantine and identification method

Step 1: Symptom inspection

Select diseased remains and suspicious seeds through a dissecting microscope to ensure the accuracy of the detection rate.

Step 2: Isolation and culture

Use V8 medium or PDA medium to isolate and culture the pathogen, and observe its morphological characteristics such as spore size and color changes.

3. Instruments and main reagents

The instruments used include biological microscope, high-speed refrigerated centrifuge, PCR instrument, etc., and the reagents are required to be analytical grade or biochemical reagent grade.

4. Experimental procedures and scientific basis

5. Comparative analysis of similar species

Table D.1 shows the differences in culture characteristics, spore size and pigment characteristics between the rapeseed black leg pathogen and similar species, which helps to accurately identify it.

6. Specific operation procedures of PCR detection

DNA extraction uses a kit or urea method, the PCR reaction system must be configured strictly according to Table C.1, and electrophoresis detection must be performed to confirm the results.

7. Implementation suggestions

In actual quarantine, samples and strains should be properly preserved to ensure data integrity and the possibility of review. Positive samples need to be stored for a long time for future reference.