Method for detecting quality of pholiota nameko strain

Abstract

The invention discloses a method for detecting the quality of a pholiota nameko strain, and belongs to the field of agriculture. The method comprises the following steps: collecting a mycelium sample after a pholiota nameko mother strain grows for 7 days, and centrifugally collecting mycelium precipitates at 4 DEG C; quickly freezing with liquid nitrogen, cracking by adopting a 0.1 mm bead milling method, adding a 1% guanidine hydrochloride buffer solution, treating at the constant temperature of 95 DEG C for 15 minutes, and then instantly cooling; then adding a standardized diazonium phosphotungstic acid reagent, reacting for 30 minutes, and measuring a light absorption value A520; performing comparative analysis on the change rate delta A of the A520 and a reference high-quality mother strain standard curve; inoculating the mother strain into a special induction culture medium containing 6-benzyladenine and 4-chlorophenoxyacetic acid, and measuring the average expansion rate V of a bacterial colony after 24 hours; and judging whether the strain quality grade is qualified, suboptimal or eliminated according to double indexes of delta A and V. The method is easy and convenient to operate, stable in detection result and suitable for large-scale strain quality evaluation, and the accuracy and the standardization level of strain screening are remarkably improved.

Description

Technical Field

[0001] This invention relates to the agricultural field, and more specifically, to a method for detecting the quality of *Pleurotus ostreatus* spawn. Background Technology

[0002] The methods for detecting the quality of *Pleurotus ostreatus* strains have evolved from subjective observation to quantitative analysis. Early methods relied primarily on sensory indicators such as mycelial morphology, growth rate, and color in petri dishes for empirical judgment. While simple to operate, these methods suffered from poor stability and were easily affected by environmental and human biases. Subsequently, tissue culture and microscopic analysis were introduced, improving the systematic nature of the detection. However, these methods remained highly dependent on operators, were difficult to standardize, and could not accurately quantify the metabolic activity of the strains.

[0003] In recent years, some studies have attempted to assess strain quality using enzyme activity or proteomics methods. While these methods have improved resolution, they require sophisticated equipment and are complex to operate, making them unsuitable for large-scale strain screening and industrial applications. Existing technologies generally suffer from the following shortcomings: low mycelial lysis efficiency, easy degradation of metabolites, unstable detection indicators, and a lack of objective quantitative standards for quality grading, making standardized evaluation difficult. Summary of the Invention

[0004] The purpose of this invention is to provide a method for detecting the quality of *Pleurotus ostreatus* strains, thereby addressing the problems mentioned in the background section: In recent years, some studies have attempted to assess strain quality using enzyme activity or proteomics methods. While these methods have improved resolution, they require sophisticated equipment and are complex to operate, making them unsuitable for large-scale strain screening and industrial applications. Existing technologies generally suffer from the following shortcomings: low mycelial lysis efficiency, easy degradation of metabolites, unstable detection indicators, and a lack of objective quantitative standards for quality grading, making standardized evaluation difficult.

[0005] Technical solution: A method for detecting the quality of *Pleurotus ostreatus* spawn includes the following steps: S1. Collect mycelial samples of Pleurotus ostreatus mother culture after 7 days of growth, and centrifuge at 4℃ to collect the mycelial precipitate. S2. The mycelial precipitate was flash-frozen in liquid nitrogen and then lysed using a 0.1 mm bead milling method, and the lysate was collected; S3. Add 1% guanidine hydrochloride buffer to the lysis buffer, keep it at 95°C for 15 minutes and then perform a quick-cooling operation; S4. After the instantaneous cooling operation, add standardized diazonium phosphotungstic acid reagent to the sample solution, react for 30 minutes, and then measure the absorbance value A. 520 ; S5. Using the absorbance value A 520 The rate of change ΔA was compared and analyzed with the corresponding curve of the reference first-grade high-quality nameko mushroom mother seed; S6. The nameko mushroom mother culture was simultaneously inoculated into a specially formulated induction medium containing 6-benzyladenine and 4-chlorophenoxyacetic acid, and the average colony expansion rate V was measured after 24 hours. S7. Based on the absorbance value A 520 The dual-index judgment method of the rate of change ΔA and the average colony expansion rate V is used to classify the nameko mushroom strain into three quality levels: qualified, sub-superior, and eliminated.

[0006] Preferably, the collection of the S1 mycelial sample further includes the following steps: S1-1. The *Pleurotus ostreatus* mother culture was cultured on potato dextrose agar medium at a constant temperature of 25°C, humidity of 60%, and light intensity of 0 lx for 7 days, ensuring that the airtightness of the culture dish was higher than 90%. S1-2. On the 7th day, use a 10mm diameter sterilized stainless steel sampling loop to sample the densest area of ​​mycelium, collecting the upper layer of mycelium with a thickness not exceeding 3mm. S1-3. Immediately transfer the collected samples to 4℃ and centrifuge at 3000rpm for 10 minutes to separate the mycelial precipitate; S1-4. Use cold chain transportation to complete the subsequent lysis steps within 15 minutes to avoid the recovery of mycelial metabolic activity.

[0007] Preferably, the method for preparing the potato dextrose agar medium in S1-1 further includes the following steps: S1-1-1. Peel and slice 200g of fresh potatoes, add deionized water to 800mL, boil for 30 minutes, then filter to obtain the juice. S1-1-2. Add 20g glucose and 18g high-purity agar to the filtrate, stir well, add liquid to 1000mL, and adjust the pH of the total solution to 6.0±0.1; S1-1-3. Sterilize with 121℃ autoclave for 20 minutes, cool to 45℃ and pour into sterile petri dishes, keeping the amount added to each dish at 18mL.

[0008] Preferably, the S3 instantaneous cooling operation adopts a two-stage cooling structure. First, the lysate after heat treatment at 95°C for 15 minutes is immediately placed in a -20°C ice-salt bath for 90 seconds, and then transferred to a -80°C dry ice-ethanol mixture for 60 seconds to stabilize the residual secondary metabolites and intracellular highly active proteins in the mushroom mycelium.

[0009] Preferably, the S4 standardized diazophosphotungstic acid reagent formula includes: 0.5g of diazo-p-nitroaniline, 4.0g of phosphotungstic acid, and 0.2g of citric acid, with deionized water added to make up to 100mL, and the pH adjusted to 4.8±0.05 using concentrated hydrochloric acid. It should be stored in a refrigerator at 4°C under light-protected conditions and used within 48 hours.

[0010] Preferably, step S4 measures the absorbance value A. 520 Includes the following steps: S4-1. After reacting for 30 minutes, take 1.0 mL of the mixture and add it to a clean cuvette with a smooth inner wall. The optical path thickness of the cuvette is fixed at 1.0 cm, and the cuvette body is made of optical grade quartz glass. S4-2. Insert the cuvette into the preheated UV-Vis spectrophotometer sample cell, set the wavelength to 520nm, and limit the reading time to no more than 2 minutes. Samples exceeding the time limit are invalid. S4-3. For each group of *Pleurotus ostreatus* mother culture samples, three independent replicate measurements were performed. The maximum and minimum absorbance values ​​were discarded, and the median value was retained as the final representative absorbance value A. 520 .

[0011] Preferably, the rate of change of absorbance ΔA in S5 is calculated using the following formula: ΔA=

[0012] Among them, the The absorbance value of the *Pleurotus ostreatus* mycelial lysate after treatment is given. The absorbance value is the absorbance value of the uninoculated mycelial culture medium after being treated with the same steps. The reference absorbance value is generated for the first-grade high-quality strain of *Pleurotus ostreatus* selected through five generations of stable subculturing.

[0013] Preferably, the quality grade division in S7 further includes the following steps: S7-1. Using the absorbance change rate ΔA as the X-axis and the average colony expansion rate V as the Y-axis, construct a two-dimensional scoring coordinate graph and delineate three scoring regions; S7-2. The qualified zone is set as ΔA≥0.85 and V≥2.5mm / h, the suboptimal zone is 0.6≤ΔA<0.85 and 1.5mm / h≤V<2.5mm / h, and the eliminated zone is ΔA<0.6 and V<1.5mm / h; S7-3. After each batch of the nameko mushroom mother culture samples is scored, the two-dimensional scoring coordinate graph is numbered, marked, and classified into files, which serve as the basis for strain updates and screening.

[0014] Preferably, the S7-1 scoring coordinate graph drawing method further includes the following steps: S7-1-1. Use the Matplotlib library in Python to automatically call sample database data and generate rating charts in batches; S7-1-2. All sample labels are automatically annotated using unique codes, and the output results are saved in PDF format and archived in chronological order to the microbial analysis database.

[0015] Compared with the prior art, the advantages of this invention are: (1) Liquid nitrogen quick-freezing combined with 0.1 mm bead milling method is introduced to lyse the mycelium of Pleurotus ostreatus, improve the lysis efficiency and retain the original state of metabolites to the greatest extent, and avoid the degradation of metabolites caused by conventional physical crushing methods.

[0016] (2) The high-temperature treatment with 1% guanidine hydrochloride solution combined with a two-stage instantaneous cooling method was adopted to fully denature and precipitate the highly active protein, which optimized the extraction purity of comparable components in the lysis solution, unlike the traditional single cooling method.

[0017] (3) A standardized diazophosphotungstic acid reagent colorimetric system is introduced, which is specifically designed to detect the aromatic metabolites that are stably present in the mycelium of Pleurotus ostreatus, thereby achieving quantitative differentiation of Pleurotus ostreatus mother species in different metabolic states, which is superior to the existing subjective colony observation method.

[0018] (4) By constructing a comparison system between ΔA and high-quality control sample absorbance values, a quantifiable absorbance change rate index is established to replace the previous imprecise standard that only assesses colony appearance.

[0019] (5) Introduce a specially formulated induction medium containing 6-benzyladenine and 4-chlorophenoxyacetic acid to improve the physiological response sensitivity of the mushroom mycelium and make the colony expansion rate reflect the difference in the activity of the strain.

[0020] (6) The dual-index cross-judgment system (ΔA and V values) is more discriminative and stable than the traditional single growth rate or microscopic observation method, and can accurately classify the three quality grades.

[0021] (7) Specific physical parameters such as temperature, time, and light intensity are set in each step of mycelial collection, lysis, reaction, and measurement to avoid the influence of human factors and improve the repeatability of test results.

[0022] (8) Use two-dimensional scoring coordinate graphs to visualize quality classification, enhance the standardization and traceability of batch tracking, and distinguish it from the traditional manual record-keeping method.

[0023] (9) The median value principle of absorbance detection is incorporated into the processing logic of repeated sample data to eliminate the influence of extreme values, so that the detection results have statistical robustness, which is better than the existing simple averaging method. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall process of a method for detecting the quality of a mushroom strain of the present invention; Detailed Implementation

[0025] For examples, please refer to Figure 1 A method for detecting the quality of a *Pleurotus ostreatus* strain includes the following steps: S1. Collect mycelial samples of Pleurotus ostreatus mother culture after 7 days of growth, and centrifuge at 4℃ to collect the mycelial precipitate. S2. The mycelial precipitate was flash-frozen in liquid nitrogen and then lysed using a 0.1 mm bead milling method, and the lysate was collected; S3. Add 1% guanidine hydrochloride buffer to the lysis buffer, keep it at 95°C for 15 minutes and then perform a quick-cooling operation; S4. After the flash cooling operation, add standardized diazonium phosphotungstic acid reagent to the sample solution, react for 30 minutes, and then measure the absorbance value A. 520 ; S5. Using absorbance value A 520 The rate of change ΔA was compared and analyzed with the corresponding curve of the reference first-grade high-quality nameko mushroom mother seed; S6. The mother culture of *Pleurotus ostreatus* was simultaneously inoculated into a specially formulated induction medium containing 6-benzyladenine and 4-chlorophenoxyacetic acid, and the average colony expansion rate V was measured after 24 hours. S7. Based on absorbance value A 520 The dual-index judgment method of the rate of change ΔA and the average colony expansion rate V is used to classify the nameko mushroom strain into three quality levels: qualified, sub-superior, and eliminated.

[0026] Specifically: Mycelial samples were cultured in 10cm standard Petri dishes, and a vertical forced-air drying incubator (model: MDF-25) was used to maintain the temperature. Centrifugation was performed using an Eppendorf 5430R refrigerated centrifuge at 3000 rpm for 10 minutes. Liquid nitrogen treatment was conducted using a liquid nitrogen tank (model: YDS-10), and lysis was performed using a BulletBlender® BeadMill bead mill with 0.1mm non-magnetic stainless steel beads for 2 minutes. Absorbance measurements were performed on a UV-Vis spectrophotometer (model: UV-2600), with a fixed path length of 1cm in the cuvettes made of optical-grade quartz glass. In the induction medium, 6-benzyladenine and 4-chlorophenoxyacetic acid were both biochemical reagent grade (≥98%), with concentrations of 1.0 mg / L and 0.5 mg / L, respectively, and the pH was adjusted to 5.8.

[0027] S1 mycelial sample collection further includes the following steps: S1-1. Culture the mother culture of *Pleurotus ostreatus* on potato dextrose agar medium at a constant temperature of 25℃, humidity of 60%, and light intensity of 0lx for 7 days, ensuring that the airtightness of the culture dish is higher than 90%. S1-2. On the 7th day, use a 10mm diameter sterilized stainless steel sampling loop to sample the densest area of ​​mycelium, collecting the upper layer of mycelium with a thickness not exceeding 3mm. S1-3. Immediately transfer the collected samples to 4℃ and centrifuge at 3000rpm for 10 minutes to separate the mycelial precipitate; S1-4. Use cold chain transportation to complete the subsequent lysis steps within 15 minutes to avoid the recovery of mycelial metabolic activity.

[0028] Specifically, culture media were sealed with sealing film to ensure airtightness. Sampling tools were stainless steel rings sterilized with ethanol and then air-dried. 15mL polypropylene centrifuge tubes were used, and the cold chain was maintained at 2–8°C during transport to the lysis equipment.

[0029] The method for preparing potato dextrose agar medium in S1-1 further includes the following steps: S1-1-1. Peel and slice 200g of fresh potatoes, add deionized water to 800mL, boil for 30 minutes, then filter to obtain the juice; S1-1-2. Add 20g glucose and 18g high-purity agar to the filtrate, stir well, add liquid to 1000mL, and adjust the pH of the total solution to 6.0±0.1; S1-1-3. Sterilize using 121℃ autoclave for 20 minutes, cool to 45℃ and pour into sterile petri dishes, keeping the amount added to each dish at 18mL.

[0030] Specifically, fresh potatoes without sprouts or disease spots are selected, double-layered gauze is used for filtration, pH value is adjusted after calibration using a pH meter (model: METTLER-TOLEDOFiveEasy), and the sterilizer model is YamatoSM510C.

[0031] The S3 instantaneous cooling operation employs a two-stage cooling structure. First, the lysate, after being heat-treated at 95°C for 15 minutes, is immediately placed in a -20°C ice-salt bath for 90 seconds, and then transferred to a -80°C dry ice-ethanol mixture for 60 seconds to stabilize residual secondary metabolites and highly active intracellular proteins in the mycelium of *Pleurotus ostreatus*.

[0032] Specifically, the -20℃ ice-salt bath was prepared using a mixture of saturated sodium chloride solution and crushed ice, while the -80℃ coolant was prepared using dry ice and anhydrous ethanol in a 1:1 volume ratio. All containers were pre-cooled, the entire operation was conducted in the dark, and a stopwatch was used to precisely time each cooling process.

[0033] The ice-salt bath was prepared with crushed ice and NaCl in a 3:1 mass ratio, and dry ice and anhydrous ethanol in a 1:1 (v / v) ratio. During the treatment, a stainless steel container with a temperature control probe was used to maintain a constant temperature, and the lysis solution was placed in a 2 mL polypropylene microtube.

[0034] The S4 standardized diazophosphotungstic acid reagent formula includes: 0.5g diazo-p-nitroaniline, 4.0g phosphotungstic acid, and 0.2g citric acid. Add deionized water to make up to 100mL, and adjust the pH to 4.8±0.05 with concentrated hydrochloric acid. Store in a refrigerator at 4°C under light-protected conditions and use within 48 hours.

[0035] Specifically: all chemical reagents are of analytical grade. After the reagent solutions are prepared, they are dispensed into brown reagent bottles, sealed and stored away from light. Before use, they are mixed on a magnetic stirrer and the pH value is confirmed by retesting with a pH meter.

[0036] S4 Measure absorbance A 520 Includes the following steps: S4-1. After reacting for 30 minutes, take 1.0 mL of the mixture and add it to a clean cuvette with a smooth inner wall. The optical path thickness of the cuvette is fixed at 1.0 cm, and the cuvette is made of optical grade quartz glass. S4-2. Insert the cuvette into the preheated UV-Vis spectrophotometer sample cell, set the wavelength to 520nm, and limit the reading time to no more than 2 minutes. Samples exceeding the time limit will be discarded. S4-3. Three independent replicate measurements were set up for each group of Pleurotus ostreatus mother culture samples. The maximum and minimum values ​​were removed from the measured absorbance values, and the median value was retained as the final representative absorbance value A. 520 .

[0037] Specifically: The spectrophotometer used is a Shimadzu UV-2600 model, which is zeroed after preheating for 30 minutes. The blank control before reading is the untreated sample solution. The interval between sample addition operations should not exceed 30 seconds. The replicate samples are set as three groups with random numbers.

[0038] The rate of change of absorbance ΔA in S5 is calculated using the following formula: ΔA=

[0039] in, The absorbance value is the value of the *Pleurotus ostreatus* mycelial lysate after treatment. The absorbance values ​​are those of uninoculated mycelial culture media treated with the same steps. The reference absorbance value is generated for the first-grade high-quality strain of *Pleurotus ostreatus* selected through five generations of stable subculturing.

[0040] Specifically: all absorbance values ​​were measured using the same instrument, repeated three times, and the median value was then used in the formula. For each batch of tests, a high-quality homologous bacterial strain should be included as a reference control to ensure batch-to-batch comparability of ΔA.

[0041] The quality grade classification in S7 further includes the following steps: S7-1. Construct a two-dimensional scoring coordinate graph with the absorbance change rate ΔA as the X-axis and the average colony expansion rate V as the Y-axis, and delineate three scoring regions; S7-2. The qualified zone is set as ΔA≥0.85 and V≥2.5mm / h, the suboptimal zone is 0.6≤ΔA<0.85 and 1.5mm / h≤V<2.5mm / h, and the eliminated zone is ΔA<0.6 and V<1.5mm / h; S7-3. After each batch of nameko mushroom mother culture samples is scored, it is numbered and marked on the two-dimensional scoring coordinate graph and classified and filed as the basis for strain renewal and screening.

[0042] Specifically, at least 6 strains were tested per batch. Statistical plots were generated using Matplotlib, and fixed thresholds were used for region division without fluctuation. The stability of the data was verified using SPSS 25.0 software, with errors controlled within ±0.05.

[0043] The method for drawing the S7-1 rating coordinate graph further includes the following steps: S7-1-1. Use the Matplotlib library in Python to automatically call sample database data and generate rating charts in batches; S7-1-2. All sample labels are automatically annotated using unique codes, and the output results are saved in PDF format and archived in chronological order to the microbial analysis database.

[0044] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples of the present invention and are not intended to limit the present invention. Various changes and modifications can be made to the present invention without departing from the spirit and scope thereof, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for detecting the quality of a Pholiota nameko strain, characterized by, The method for detecting the quality of the pholiota name includes the following steps: S1. Collecting mycelium samples of the pholiota name after 7 days of growth, centrifuging the mycelium precipitate at 4°C; S2. The mycelium precipitate is frozen in liquid nitrogen and then cracked by 0.1mm bead milling method, and the cracking solution is collected; S3. Adding 1% guanidine hydrochloride buffer to the cracking solution, treating at 95°C for 15 minutes, and then performing instant cooling operation; S4. After the quenching operation, the standardised diazotised phosphotungstic acid reagent is added to the sample solution and the absorbance A is measured after 30 minutes of reaction 520 ; S5. with the rate of change of the absorbance value A 520 comparison analysis with the corresponding curve of the reference first-class high-quality Pholiota nameko mother culture; S6. The pholiota name is inoculated into a special induction medium containing 6-benzyladenine and 4-chlorophenoxyacetic acid at the same time, and the average colony expansion rate V is measured after 24 hours; S7. The method of S6, wherein the quality of the mushroom spawn is determined based on a rate of change of the absorbance value A and an average expansion rate V of the colonies. 520 S7. The method of S6, wherein the quality of the mushroom spawn is determined based on a rate of change of the absorbance value A and an average expansion rate V of the colonies.

2. The method for detecting the quality of the Pholiota nameko strain according to claim 1, characterized in that, The S1 mycelium sample collection further includes the following steps: S1-1. Incubate the pholiota name on potato dextrose agar medium at 25°C, 60% humidity, and 0lx light intensity, and ensure that the culture dish is sealed to more than 90%; S1-2. On the 7th day, use a 10mm diameter sterilized stainless steel sampling ring to sample in the most dense area of mycelium, and collect the upper mycelium with a thickness of not more than 3mm; S1-3. Immediately transfer the collected sample to 4°C, centrifuge at 3000rpm for 10 minutes, and separate the mycelium precipitate; S1-4. Use cold chain transportation to complete the subsequent cracking step within 15 minutes to avoid recovery of mycelial metabolic activity.

3. The method for detecting the quality of the Pholiota nameko strain according to claim 2, characterized in that, The preparation method of the potato dextrose agar medium in S1-1 further includes the following steps: S1-1-1. Peel and slice 200g fresh potatoes, add deionized water to 800mL, boil for 30 minutes, and then filter the juice; S1-1-2. Add 20g glucose and 18g high-purity agar to the filtrate, stir evenly, make up the solution to 1000mL, and adjust the total solution pH to 6.0±0.1; S1-1-3. Use 121°C high-pressure steam sterilization for 20 minutes, cool to 45°C, and then pour into sterile culture dishes, with an addition of 18mL per dish.

4. The method for detecting the quality of the Pholiota nameko spore mass according to claim 1, characterized in that, The instant cooling operation in S3 uses a two-stage cooling structure, first placing the cracking solution treated at 95°C for 15 minutes in a-20°C ice-salt bath for 90 seconds, and then transferring it to a-80°C dry ice-ethanol mixture for 60 seconds to stabilize the residual secondary metabolites and intracellular high-activity proteins in the pholiota mycelium.

5. The method for detecting the quality of the Mycena purpureofusca strain according to claim 1, characterized in that, The S4 standardized diazonium phosphotungstic acid reagent formula includes: diazonium p-nitroaniline 0.5g, phosphotungstic acid 4.0g, citric acid 0.2g, add deionized water to 100mL, and use concentrated hydrochloric acid to adjust the pH to 4.8±0.05, store in a 4°C refrigerator in the dark, and use within 48 hours.

6. The method for detecting the quality of the Mycelioporella capernonii strain according to claim 5, characterized in that, The S4 assay measures absorbance A 520 comprising the steps of: S4-1. After 30 minutes of reaction, 1.0mL of the mixture is added to a clean cuvette with smooth inner walls, the optical path thickness of the cuvette is fixed at 1.0cm, and the cuvette body material is optical grade quartz glass; S4-2. Insert the cuvette into the preheated UV-visible spectrophotometer sample cell, set the wavelength to 520nm, and limit the reading time to not more than 2 minutes, and the sample is invalid if the time is exceeded; S4-3. Each group of the Mycena sublaevipes mother culture sample is set up 3 independent repeated measurements, the maximum and minimum values of the measured absorbance values are removed, and the median value is retained as the final representative of the absorbance value A 520 .

7. The method for detecting the quality of the Mycena purpureofusca strain according to claim 1, characterized in that, The absorbance change rate ΔA in S5 is calculated by the following formula: ΔA= 8. wherein, The is the light absorption value of the treated mycelium lysate of the test Pholiota nameko, and the is the light absorption value of the medium without inoculation of mycelium treated by the same steps, and the is the reference light absorption value produced by the first-class high-quality strain screened out by five generations of stable subculture of the Pholiota nameko mother strain.

9. The method for detecting the quality of the Pholiota nameko spore mass according to claim 1, characterized in that, The quality grade division in S7 further comprises the following steps: S7-1. Construct a two-dimensional score coordinate graph with the absorbance change rate ΔA as the X-axis and the average colony expansion rate V as the Y-axis, and divide it into three score regions; S7-2. The qualified region is set as ΔA≥0.85 and V≥2.5 mm / h, the sub-optimal region is 0.6≤ΔA<0.85 and 1.5 mm / h≤V<2.5 mm / h, and the elimination region is ΔA<0.6 and V<1.5 mm / h; S7-3. After scoring, each batch of Pholiota nameko mother strain sample is numbered and classified on the two-dimensional score coordinate graph and is filed as a basis for strain updating and screening.

10. The method for detecting the quality of the Pholiota nameko spore mass according to claim 8, characterized in that, The scoring coordinate graph drawing method in S7-1 further comprises the following steps: S7-1-1. Use the Matplotlib library in Python language to automatically call the sample database data and generate scoring graphs in batches; S7-1-2. All sample marks are automatically annotated using unique codes, and the output results are saved in PDF format and filed in the strain analysis database in chronological order.

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