Research On Rice Seed Viability Evaluation System Under Thermal Stress Based On Electrical Impedance Spectroscopy

Rice is one of the most important food crops in the world,and the quality and quantity of its seeds directly affect food yield and quality.The study of its vitality can help to understand key indicators such as seed germination rate,growth rate,disease resistance,etc.,so as to optimize the cultivation,storage and utilization of seeds,and improve rice yield and quality,which is of great significance for promoting sustainable agricultural development.In this paper,a rice seed viability assessment system under thermal stress based on electrical impedance spectroscopy is designed,including a special rice seed clamping device,and the software and hardware design of impedance collector,the specific research content is as follows:1.To ensure stable detection,a rice seed clamping device with Ag/AgCl electrodes was designed,and the contact area with the sample to be tested is 0.1 cm~2.Through single-factor testing,it was found that under the conditions of a detection voltage U of0.5 V,a frequency band of 200 Hz～4 MHz,a fixed frequency detection frequency f of500 k Hz,and an applied pressure F of 2 N,the test data showed good stability.2.This study designed an impedance acquisition circuit.Including analog switching electrodes,voltage driving constant current source,signal conditioning and acquisition,data storage and transmission and other modules,and debug the adapted software to drive the system,allocate parameters,collect data and other tasks.In the specific implementation,analog switching electrodes are used to realize the switching of electrodes,voltage drives constant current source to ensure the stability of current,signal conditioning and acquisition module to process and collect the collected signals,data storage and transmission module to realize data storage and transmission,and also design a temperature control module,which can change seed moisture under heat stress and provide data support for the later seed division gradient.3.The above designed system was used to carry out experiments,the collected data were analyzed by impedance spectrum method,and the temperature compensation model was used to analyze the situation of different varieties of rice under heat stress,and optimized by temperature compensation method and area normalization method.Finally,the standard germination method was used to evaluate and analyze the vitality of rice seeds,which could clearly compare the vitality differences of rice seeds and construct an impedance-viability detection model.Through experiments,it is found that seed viability has a negative correlation with electrical impedance,that is,the higher the seed vitality,the lower the change rate of electrical impedance.Based on this relationship,an impedance spectroscopy analysis method was proposed for detecting the vitality of rice seeds and evaluating and screening seed quality.The system has low assembly cost and short detection time,and can produce results in just 5 seconds,with an accuracy of up to 95%.Therefore,this method can serve as an effective means of detecting the quality of rice seeds and provide technical support for the rice cultivation industry.