GB/T 36838-2018 in English

GB/T 36838—2018 Standard Overview

Chenopodium murale L. (scientific name: Chenopodium murale L.) is an important quarantine object, belonging to the Chenopodiaceae family. This standard specifies the quarantine identification method for Chenopodium murale, which is applicable to its detection and identification in plant raw grains, seeds and other products.

Background and significance of standard formulation

This standard was proposed and coordinated by the National Technical Committee for Plant Quarantine Standardization, and the drafting units include the Fujian Entry-Exit Inspection and Quarantine Bureau of the People's Republic of China and other authoritative institutions. Chenopodium murale poses a threat to agricultural production and the ecological environment due to its strong ability to spread and easy to spread through trade channels. Therefore, it is of great practical significance to establish a scientific quarantine identification method.

Interpretation of main technical contents

1. Scope of quarantine identification and definition of terms

2. Laboratory quarantine and identification process

Laboratory testing steps include sample preparation, screening test and microscopic examination and identification:

1. Sample preparation: Use the quartering method to take 1/2 to 3/4 of the average sample, weigh and record the mass.
2. Sieving test: Select the sieve size according to the individual size of the sample, and separate the sample by gyratory or electric oscillation.
3. Microscopic examination and identification: Use a stereo microscope or a scanning electron microscope to observe the external and anatomical characteristics of the seeds.

3. Comparison of identification characteristics

There are significant differences between the leaf shape, inflorescence structure and fruit morphology of the wall-shaped and similar species. The following are the key identification points:

• Leaf: triangular to broad rhombus, base cuneate or truncate, edge serrated.
• Inflorescence: Cyme, small and terminal or axillary.
• Fruit: The fruit is covered with perianth, and the pericarp has warty protrusions.

4. Implementation suggestions and precautions

In order to ensure the accuracy and efficiency of quarantine work, the following suggestions are put forward:

1. Staff training: Regularly organize professional training for identification technicians.
2. Equipment maintenance: Ensure the normal operation of instruments such as stereo microscope and scanning electron microscope.
3. Sample preservation: Properly preserve the detected Chenopodium album specimens and samples for at least 6 months.

Comparison and optimization suggestions for standard framework

Through comparative analysis with quarantine standards of other countries and regions, it was found that:

• This standard has high scientificity and operability in identification methods.
• It is recommended to further refine the seed processing steps and increase the application of rapid detection technology.