Cistanche deserticola seed screening method based on infrared spectrum

Abstract

The invention discloses a cistanche seed screening method based on an infrared spectrum, and relates to the technical field of seed screening. The method comprises the steps of seed grading data determination, infrared spectrum detection and data processing and analysis. The seed grading data determination specifically comprises the steps of clarity determination, thousand seed weight determination, seed vigor determination and moisture content determination. According to the method, different grades of cistanche seeds are obviously related to infrared spectrum characteristic peaks, and the characteristic peaks have relatively high positive correlation with thousand seed weight, seed activity and moisture content, so that the absorbance of a wave band corresponding to a cistanche seed sample is an important index capable of reflecting the quality of the seeds; the absorbance is remarkably related to the thousand seed weight and the seed activity, and the effectiveness and accuracy of the infrared spectrum technology in evaluating the quality, the activity and the thousand seed weight of the seeds are proved.

Description

Technical Field

[0001] The invention relates to the field of seed screening, and in particular to a Cistanche deserticola seed screening method based on infrared spectroscopy. Background Art

[0002] The traditional Cistanche deserticola seed quality evaluation method can evaluate the seed quality to a certain extent, but it has many shortcomings. The seed grading method is used to determine the seed quality, which requires the determination of indicators such as thousand-grain weight, seed vitality, and moisture. It not only requires professional instruments, but also takes a long time. In the process of seed germination rate determination, seeds with a particularly long germination period require a longer determination time, which increases the complexity of the experiment and the instability of the determination results. In addition, it is also difficult to determine the vitality of particularly small seeds using the TTC (2,3,5-triphenyltetrazolium chloride) staining method. Summary of the invention

[0003] The purpose of the invention is to overcome the complexity and instability of determining seed quality in the prior art and to provide a Cistanche deserticola seed screening method based on infrared spectroscopy.

[0004] The objective of the present invention is achieved through the following technical solutions:

[0005] A method for screening Cistanche deserticola seeds based on infrared spectroscopy, the method comprising the following steps:

[0006] S1. Seed grading data determination: including the determination of the following four data:

[0007] Select Cistanche deserticola seed samples, the number of seed samples is not less than one thousand; the seed samples are all taken from mature Cistanche deserticola plants;

[0008] Purity determination: Prepare the Cistanche deserticola seed sample, the number of seed samples is not less than one thousand seeds, after removing impurities and non-seed components, calculate the ratio of the weight of clean seeds to the weight of the total seed sample, and prepare for the thousand-seed weight determination;

[0009] Thousand-grain weight determination: Mix the seed sample thoroughly and measure the weight of one thousand seed samples, that is, randomly select 100 seeds and weigh and record them on a 1 / 10,000 analytical balance, and calculate the weight of 1,000 seeds; repeat the experiment 5 times to obtain the thousand-grain weight data of seeds;

[0010] Seed vigor determination: The seed coats of the seeds in the selected seed samples are removed. The TTC (2,3.5 triphenyl hydrochloride) method is a fast, simple and accurate method for determining seed vigor. It uses the reduction effect of the seeds during respiratory metabolism to determine their vigor. This method is widely used in seed production, trade and research.

[0011] Use 0.5% TTC dye solution for 24 hours, record the number of viable and inviable seeds according to the staining situation, calculate the viability, and take the average value as the viability of the seed sample. Repeat the experiment 5 times;

[0012] Moisture content determination: Place the seed sample in a weighing bottle with constant weight and weigh it; spread the seeds in the seed sample evenly and put them in an oven, wait for the oven temperature to rise to 130±2℃ and start timing, and dry for 12 hours; seal the lid of the weighing bottle in the oven, take it out and quickly put it in a dryer to cool for 30 minutes, and accurately weigh it; then dry it again in the dryer for 2 hours under the above conditions, take it out and put it in a dryer, cool at room temperature for 30 minutes, and accurately weigh it again; compare the weight before drying with the weight after drying to obtain the moisture content data of the seed sample:

[0013] (Weight of seed sample before drying - weight of seed sample after drying) / weight of seed sample before drying;

[0014] S2. Infrared spectrum detection:

[0015] The seed samples were scanned 16 times cumulatively, and the interference of H2O and CO2 was deducted in real time during the scanning. The infrared spectrum detection of the seed samples was repeated 3 times with potassium bromide as the background.

[0016] S3. Data processing and analysis: Process and analyze the data obtained after seed grading and infrared detection, specifically:

[0017] The statistical results of the data after the seed grading test were analyzed using SPSS; the infrared spectrum detection results were collected using Spectrum10.03 software, and the original spectrum data was preprocessed using OMNIC8.2 software to complete baseline correction, smoothing, average spectrum and derivative spectrum calculation, and then the absorbance corresponding to the characteristic peak was found using Origin9 software; the processed data were used to analyze the correlation between the seed grading results and the characteristic peaks of the infrared spectrum.

[0018] Furthermore, before the infrared spectrum detection, the seed sample needs to be fully dried, the crushed seed sample is passed through a 200-mesh sieve, 2 mg of seed sample powder is taken and put into a mortar, and then 200 mg of KBr powder is put into the mortar and mixed with the seed sample powder and ground until there are no obvious particles, and then transferred to a mold, and the no obvious particles are compressed at 20 MPa for 1 min to make the no obvious particles pressed into a nearly transparent thin sheet.

[0019] Furthermore, the scanning conditions of the infrared spectrum detection are: the indoor temperature is kept in the range of 18-22°C, the humidity is kept below 30%, and the spectral range is 4000-400cm -1 , resolution 4cm-1 .

[0020] The beneficial effects of the present invention are:

[0021] (1) Compared with traditional seed grading and other quality evaluation methods, infrared spectroscopy is simple to operate, low-cost, non-destructive and efficient. Through infrared spectroscopy, information on the internal chemical composition of seeds can be directly obtained, thus realizing rapid evaluation of seed quality.

[0022] (2) It was found that there was a significant correlation between the quality indicators of Cistanche deserticola seeds and the characteristic peaks of infrared spectra. This discovery can realize the rapid determination and screening of the quality of Cistanche deserticola seeds of different grades, greatly improve the efficiency and accuracy of seed grading and quality assessment, and provide technical support for the standardization and modernization of related industries. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is the circular system cluster diagram of the four indicators of Cistanche deserticola seeds;

[0024] Figure 2 This is the quality classification percentage of the three-grade Cistanche seeds from 36 different origins;

[0025] Figure 3 This is the infrared spectrum of Cistanche deserticola seeds from 36 different origins;

[0026] Figure 4 This is a correlation analysis diagram of seed traits and characteristic peak absorbance. DETAILED DESCRIPTION

[0027] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0028] The seeds of mature plants of Cistanche deserticola were collected from 36 production areas. After identification and confirmation that the seeds were all from Cistanche deserticola, the seeds were removed from the mature plants, cleaned, and stored at room temperature, in a dry and ventilated condition.

[0029] The equipment includes: 101 type electric heating blast drying oven; 0.4mm, 0.5mm, 0.6mm and 0.7mm type sieves; SpectrumTwo type Fourier transform infrared spectrometer; YP-2 tablet press; AB265-S (1 / 100,000) electronic balance; agate mortar; KBr spectrally pure.

[0030] Select Cistanche deserticola seed samples, the number of seed samples is not less than one thousand; the seed samples are all taken from mature Cistanche deserticola plants;

[0031] S1. Seed grading data determination: including the determination of the following four data:

[0032] Purity determination: Prepare the Cistanche deserticola seed sample, the number of seed samples is not less than one thousand seeds, after removing impurities and non-seed components, calculate the ratio of the weight of clean seeds to the weight of the total seed sample, and prepare for the thousand-seed weight determination;

[0033] Thousand-grain weight determination: Mix the seed sample thoroughly and measure the weight of one thousand seed samples, that is, randomly select 100 seeds and weigh and record them on a 1 / 10,000 analytical balance, and calculate the weight of 1,000 seeds; repeat the experiment 5 times to obtain the thousand-grain weight data of seeds;

[0034] Seed vigor determination: Select seed samples, remove the seed coat, and use 0.5% TTC dye solution to dye for 24 hours. According to the dyeing situation, record the number of viable and non-viable seeds, calculate the vigor, and take the average value as the vigor of the seed sample. Repeat the experiment 5 times;

[0035] Moisture content determination: Weigh the seed sample in a weighing bottle with constant weight; spread the seed sample evenly and put it in an oven, wait for the oven temperature to rise to 130±2℃ and start timing, and dry it for 12 hours; seal the lid of the weighing bottle in the oven, take it out and quickly put it in a desiccator to cool for 30 minutes, and accurately weigh it; then dry it again in the desiccator for 2 hours under the above conditions, take it out and put it in a desiccator, cool it at room temperature for 30 minutes, and accurately weigh it again; compare the weight before drying with the weight after drying to obtain the moisture content data of the seed sample:

[0036] (Weight of seed sample before drying - weight of seed sample after drying) / weight of seed sample before drying;

[0037] S2. Infrared spectrum detection:

[0038] The seed samples were scanned 16 times cumulatively, and the interference of H2O and CO2 was deducted in real time during the scanning; the seed samples were repeated 3 times with potassium bromide as the background;

[0039] S3. Data processing and analysis: Process and analyze the data obtained from seed grading and infrared detection, specifically:

[0040] The statistical results of the data after the seed grading test were analyzed using SPSS; the infrared spectrum detection results were collected using Spectrum10.03 software, and the original spectrum data was preprocessed using OMNIC8.2 software to complete baseline correction, smoothing, average spectrum and derivative spectrum calculation, and then the absorbance corresponding to the characteristic peak was found using Origin9 software; the processed data were used to analyze the correlation between the seed grading results and the characteristic peaks of the infrared spectrum.

[0041] After analyzing the correlation between the seed grading results and the characteristic peaks of the infrared spectrum, it was concluded that the purity of Cistanche seeds ranged from 68.84% to 97.63%, indicating that there were certain differences in the purity of seeds in the seed samples; the thousand-grain weight of the seeds ranged from 49.18 mg to 98.6 mg, showing that the quality of the seeds varied greatly; the vigor of the seeds ranged from 19.81% to 63.97%, and the moisture content of the seeds ranged from 4.97% to 8.08%, as shown in Table 1. The measurement results showed that there were certain differences in the thousand-grain weight, seed vigor and moisture content of Cistanche seeds from different origins.

[0042] Table 1 Results of seed purity, thousand-grain weight, seed vitality and moisture content

[0043]

[0044] See also Figure 3 And Table 2, through the cluster analysis of the four indicators of Cistanche deserticola, Table 2 is the K cluster analysis table of seed quality index test results. According to the analysis, seeds from different origins are divided into three categories, which can be specifically classified as follows:

[0045] Category 1: 1, 2, 3, 10, 13, 14, 15, 16, 18, 19, 20, 22, 23, 25, 28, 29, 31, 32, 36;

[0046] Category II: 4, 5, 7, 8, 27, 33, 34;

[0047] Three categories: 6, 9, 11, 12, 17, 21, 24, 26, 30, and 35.

[0048] The grade of Cistanche deserticola seeds was determined by calculating the average values ​​of the four indicators of seed purity, seed vigor, moisture content and 1000-grain weight. The grading standards are shown in Table 3. The standards are as follows: first-grade seeds have a purity of ≥85%, 1000-grain weight ≥80 mg, seed vigor ≥50%, moisture content ≥6.5%, and particle size ≥0.7 mm; second-grade seeds have a purity between 75% and 85%, a 1000-grain weight between 70 mg and 80 mg, seed vigor between 35% and 50%, moisture content between 6% and 6.5%, and particle size between 0.5 mm and 0.7 mm; third-grade seeds have a purity of ≤75%, 1000-grain weight ≤70 mg, seed vigor of ≤35%, moisture content ≤6%, and particle size ≤0.5 mm.

[0049] Table 2 Seed quality index test results K cluster analysis results

[0050]

[0051] Table 3 Seed quality grading standards

[0052]

[0053] See also Figure 2 According to the seed quality grading standard, the Cistanche seeds from 36 different origins are arranged in proportion according to the quality grading standard, and a comparative analysis can be made on the quality grades of the 36 origins.

[0054] See also Figure 3 The characteristic peak absorbance of infrared spectra of seeds of different grades showed a high positive correlation at each wavelength, and the correlation coefficient was close to or equal to 1. Figure 3 As shown in the figure, the infrared spectra of seeds from different origins are significantly different. The characteristic peak differences such as (OH) in the 2925 band, (CH) in the 2854 band, (C=O) in the 1742 and 1636 bands, C=C bonds in the 1513 band and CO in the 1030 band can clearly distinguish different grades of Cistanche deserticola seeds. Table 4 is a characteristic peak identification table.

[0055] Table 4 Characteristic peak identification wave number data list

[0056]

[0057] The following table shows the infrared spectrum characteristic peak absorbance of Cistanche deserticola seeds corresponding to 36 origins;

[0058] Table 5 Infrared spectrum characteristic peak absorbance table

[0059]

[0060] See also Figure 4, different seed grading indices have significant correlation with infrared spectrum characteristic peaks, thousand-grain weight and infrared spectrum characteristic peak absorbance at different wavelengths show significant positive correlation, with correlation coefficients ranging from 0.487 to 0.613, while the correlation coefficients between seed vigor and infrared spectrum characteristic peak absorbance at different wavelengths range from 0.434 to 0.531, indicating significant correlation;

[0061] The characteristic peaks of infrared spectrum of Cistanche deserticola seeds can significantly distinguish seeds of different grades and show significant positive correlation with seed thousand-grain weight and vitality. -1 and 2854cm -1 The characteristic peaks of 1742cm have a high positive correlation with 1000-grain weight, seed vitality and moisture content, indicating that the absorbance of these two bands can reflect the important indicators of seed quality; -1 and 1636cm -1 The absorbance at 1030 cm was significantly correlated with thousand-grain weight and seed vigor, further supporting their validity as predictors of seed quality; -1 Although the correlation is slightly lower, it still has a certain positive correlation with thousand-grain weight and seed vigor.

[0062] All of the above demonstrate the effectiveness and accuracy of infrared spectroscopy in evaluating seed quality, vigor and thousand-grain weight.

[0063] Compared with traditional quality evaluation methods such as seed grading, infrared spectroscopy is simple to operate, low-cost, non-destructive and efficient. Through infrared spectroscopy, information on the internal chemical composition of seeds can be directly obtained to evaluate seed quality.

[0064] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not deviate from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. A method for screening Cistanche deserticola seeds based on infrared spectroscopy, characterized in that: The method steps include: S1. Seed grading data determination: including the determination of the following four data: Select Cistanche deserticola seed samples, the number of seed samples is not less than one thousand; the seed samples are all taken from mature Cistanche deserticola plants; Purity determination: Select Cistanche deserticola seed samples, the number of seed samples is not less than one thousand seeds, after removing impurities and non-seed components, calculate the ratio of the weight of clean seeds to the weight of the total seed sample, and prepare for the thousand-seed weight determination; Thousand-grain weight determination: Mix the seed sample thoroughly and measure the weight of one thousand seed samples; Seed vigor determination: Remove the seed coat from the selected seed samples, use 0.5% TTC dye solution to dye for 24 hours, record the number of viable and non-viable seeds according to the dyeing situation, calculate the vigor, and take the average value as the vigor of the seed sample. Repeat the experiment 5 times; Determination of moisture content: Place the seed sample in a weighing bottle with constant weight and weigh it; spread the seeds in the seed sample evenly and put them in an oven, wait for the oven temperature to rise to 130±2℃ and start timing, and dry for 12 hours; seal the lid of the weighing bottle in the oven, take it out and quickly put it in a dryer to cool for 30 minutes, and weigh it; then dry it again in the dryer under the same conditions for 2 hours, take it out and put it in a dryer, cool at room temperature for 30 minutes, and weigh it again; compare the weight before drying with the weight after drying to obtain the moisture content data of the seed sample: (Weight of seed sample before drying - weight of seed sample after drying) / weight of seed sample before drying; S2. Infrared spectrum detection: The seed samples were scanned 16 times cumulatively, and the interference of H2O and CO2 was deducted in real time during the scanning. The infrared spectrum detection of the seed samples was repeated 3 times with potassium bromide as the background. S3. Data processing and analysis: Process and analyze the data obtained after seed grading and infrared detection, specifically: The statistical results of the data after the seed grading test were analyzed using SPSS; the infrared spectrum detection results were collected using Spectrum, and the original spectrum data was preprocessed using OMNIC to complete baseline correction, smoothing, average spectrum and derivative spectrum calculation, and then the absorbance corresponding to the characteristic peak was found through Origin; the processed data was used to analyze the correlation between the seed grading results and the characteristic peaks of the infrared spectrum.

2. The method for screening Cistanche deserticola seeds based on infrared spectroscopy according to claim 1, characterized in that: Before the infrared spectrum detection, the seed sample needs to be fully dried and crushed. The crushed seed sample is passed through a 200-mesh sieve, 2 mg of seed sample powder is taken and put into a mortar, and then 200 mg of KBr powder is put into the mortar and mixed with the seed sample powder and ground until there are no obvious particles, and then transferred to a mold. Under 20 MPa conditions, the sample without obvious particles is compressed for 1 minute to make the no obvious particles pressed into a nearly transparent thin sheet.

3. The method for screening Cistanche deserticola seeds based on infrared spectroscopy according to claim 1, characterized in that: The scanning conditions of the infrared spectrum detection are: the indoor temperature is kept in the range of 18-22°C, the humidity is kept below 30%, and the spectral range is 4000-400cm -1 , resolution 4cm -1 .

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