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CN-121978177-A - Electrochemical detection method for rhododendron wilt

CN121978177ACN 121978177 ACN121978177 ACN 121978177ACN-121978177-A

Abstract

The invention provides an electrochemical detection method for rhododendron wilt, belongs to the technical field of flower disease detection, and solves the technical problems of high destructiveness, long period and high operation threshold of the existing detection method. The method comprises the steps of analyzing volatile components of infection and healthy azalea samples through a GC-IMS technology, screening terpineol to serve as a specific characteristic marker of fusarium wilt, determining optimal parameters of electrochemical detection through a single factor optimization experiment, wherein the optimal parameters comprise pH5.7-7.2, temperature 40-60 ℃, reaction time 8-15min and scanning speed 0.02-0.10V/s, configuring characteristic marker standard solutions with different concentrations, establishing an electrochemical detection working curve, calculating detection limit, carrying out nondestructive collection on volatile components of samples to be detected, detecting response signals through an electrochemical working station, and judging disease infection conditions through combining the working curve. The invention realizes nondestructive and rapid detection of the rhododendron wilt, has short detection period, convenient operation and high sensitivity and accuracy, and can be matched with portable equipment to realize field detection.

Inventors

  • HE YANG
  • GUAN HUANAN
  • LU YUJIE
  • WANG LEI

Assignees

  • 何阳

Dates

Publication Date
20260505
Application Date
20260321

Claims (10)

  1. 1. An electrochemical detection method for rhododendron wilt is characterized by comprising the following steps: 1) The volatile components of the azalea sample infected with azalea wilt and the healthy azalea sample are respectively analyzed by adopting a GC-IMS gas chromatography-ion mobility spectrometry technology, and volatile odor molecules with azalea wilt specificity are screened out to be used as characteristic markers; 2) Based on the characteristic that the characteristic marker generates specific oxidation-reduction reaction on the surface of the electrode, electrochemical detection is carried out on the characteristic marker by utilizing an electrochemical workstation, and electrochemical detection parameters are determined through a single-factor optimization experiment, wherein the electrochemical detection parameters comprise detection system pH, detection temperature, reaction time and scanning rate; 3) Preparing standard solutions of the characteristic markers with different concentrations, detecting the standard solutions with different concentrations by using an electrochemical detection system after determining parameters, establishing an electrochemical detection working curve of the rhododendron wilt, and calculating to obtain a detection limit; 4) Collecting volatile components of a azalea sample to be detected, adding the collected volatile components into an electrochemical detection system with determined parameters, detecting by an electrochemical workstation to obtain an electrochemical response signal, and judging whether the azalea sample to be detected is infected with azalea wilt or not according to the electrochemical detection working curve.
  2. 2. The electrochemical detection method for the rhododendron wilt according to claim 1, wherein the GC-IMS analysis in step 1) includes collecting volatile components of the rhododendron sample, sampling, gas chromatographic separation and ion mobility spectrometry detection, and screening of the feature markers is completed by comparing GC-IMS two-dimensional spectrograms, differential spectrograms and fingerprint spectrograms of the infected and healthy samples.
  3. 3. The electrochemical detection method for the rhododendron wilt according to claim 1, wherein the characteristic marker screened in the step 1) is terpineol, and the terpineol is a volatile odor molecule specifically generated after the rhododendron is infected with the wilt.
  4. 4. The electrochemical detection method for the rhododendron wilt according to claim 1, wherein the single factor optimization experiment in the step 2) examines the influence of the pH, the temperature, the reaction time and the scanning rate on the peak current of the electrochemical detection system, and determines the optimal value of each parameter by taking the maximum peak current and stable detection signal as optimization targets.
  5. 5. The electrochemical detection method for the rhododendron wilt according to claim 4, wherein the optimal pH of the electrochemical detection system is 5.7-7.2, the optimal detection temperature is 40-60 ℃, and the optimal reaction time is 8-15min.
  6. 6. The electrochemical detection method for rhododendron wilt according to claim 4, wherein the optimization of the scanning rate is based on a good linear relationship between square root of the scanning rate and peak current, and a correlation coefficient R2 of the linear relationship is not less than 0.99.
  7. 7. The electrochemical detection method for the rhododendron wilt according to claim 1, wherein the detection method of the electrochemical workstation in the step 2) is cyclic voltammetry CV, and electrochemical response signals such as an oxidation peak current value, a reduction peak current value, an oxidation reduction potential and the like are recorded in the detection process.
  8. 8. The electrochemical detection method for the rhododendron wilt according to claim 1, wherein the standard solution of the feature marker in the step 3) is configured into a plurality of concentration gradients, the concentration gradients cover low, medium and high concentration ranges, the feature marker concentration is used as an abscissa after detection, the absolute value of the corresponding oxidation peak current value is used as an ordinate, and a linear electrochemical detection working curve is obtained through fitting.
  9. 9. The electrochemical detection method for the rhododendron wilt according to claim 1, wherein the volatile components of the rhododendron sample to be detected in the step 4) are collected in a nondestructive mode, and tissues and organs such as plants, leaves, root systems and the like of the rhododendron are not damaged in the collecting process.
  10. 10. The electrochemical detection method for rhododendron wilt according to any one of claims 1 to 9, wherein the method is applied to detection of rhododendron wilt in import and export flower quarantine, field screening of flower planting bases, market disease detection scenes of gardening flower trade.

Description

Electrochemical detection method for rhododendron wilt Technical Field The invention belongs to the technical field of flower disease detection, and particularly relates to an electrochemical detection method for azalea wilt. Background Azalea is a core ornamental flower product in China, is also an important product for import and export of flower trade, occupies important positions in gardening industry and flower economy, and has a continuously growing industrial scale. The rhododendron wilt is a high-risk soil-borne disease caused by pathogenic fungi, has the remarkable characteristics of strong infectivity, high mortality and strong concealment, not only can cause flower plant batch death and bring huge economic loss to the flower industry, but also is an important prevention and control object for import and export flower quarantine in China, thus realizing rapid and accurate detection of the disease, and being a key premise for guaranteeing safe production of the flower industry and improving port clearance efficiency. The current mainstream detection method for azalea wilt mainly comprises pathogen isolated culture, molecular biological detection and field phenotype identification. The traditional pathogen separation culture method needs destructive sampling of flower samples, the detection period is 3-7 days, the timeliness is serious, the quick screening requirement cannot be met, the molecular biology detection is improved in detection precision, sample tissues are still required to be destroyed to extract nucleic acid, the pretreatment operation flow is complex, meanwhile, the special laboratory equipment and special operators are highly relied on, the detection work is difficult to develop on site, the field phenotype identification is influenced by the disease concealment, the identification can be realized only after plants show obvious wither symptoms, and the best prevention and control time is easy to miss. The existing detection technology has the inherent defects of large detection destructiveness, long detection period and high operation threshold, can not simultaneously meet the requirements of nondestructive, rapid and accurate detection, and is difficult to adapt to the industry requirement of batch, rapid and nondestructive screening of samples in import and export flower quarantine sites, so that the development of an efficient and high-sensitivity azalea wilt detection method becomes an urgent requirement in the field of disease prevention and control of flower industry. Disclosure of Invention In order to solve the technical problems, the invention provides an electrochemical detection method for the rhododendron wilt, which solves the technical problems that the existing detection method for the rhododendron wilt has large destructiveness, long detection period and high operation threshold, can not meet the requirements of nondestructive, quick and accurate detection, and is difficult to meet the requirement of the mass quick screening industry on import and export flower quarantine sites. An electrochemical detection method for azalea wilt comprises the following steps: 1) The volatile components of the azalea sample infected with azalea wilt and the healthy azalea sample are respectively analyzed by adopting a GC-IMS gas chromatography-ion mobility spectrometry technology, and volatile odor molecules with azalea wilt specificity are screened out to be used as characteristic markers; 2) Based on the characteristic that the characteristic marker generates specific oxidation-reduction reaction on the surface of the electrode, electrochemical detection is carried out on the characteristic marker by utilizing an electrochemical workstation, and electrochemical detection parameters are determined through a single-factor optimization experiment, wherein the electrochemical detection parameters comprise detection system pH, detection temperature, reaction time and scanning rate; 3) Preparing standard solutions of the characteristic markers with different concentrations, detecting the standard solutions with different concentrations by using an electrochemical detection system after determining parameters, establishing an electrochemical detection working curve of the rhododendron wilt, and calculating to obtain a detection limit; 4) Collecting volatile components of a azalea sample to be detected, adding the collected volatile components into an electrochemical detection system with determined parameters, detecting by an electrochemical workstation to obtain an electrochemical response signal, and judging whether the azalea sample to be detected is infected with azalea wilt or not according to the electrochemical detection working curve. Preferably, the GC-IMS analysis in step 1) includes collecting volatile components of azalea samples, sampling, gas chromatographic separation and ion mobility spectrometry detection, and screening of feature markers is completed by comparing GC-IMS t