Bioimpedance-based evaluation of relative leaf age in mango twigs using electrical impedance spectroscopy

Area of Science:

• Agricultural Science
• Plant Physiology
• Electrical Engineering

Background:

• Accurate assessment of plant physiological age is crucial for crop management and yield prediction.
• Traditional methods for determining leaf age can be destructive and time-consuming.
• Developing non-destructive techniques for plant phenotyping is an active area of research.

Purpose of the Study:

• To propose and validate a non-destructive method for estimating the relative age of mango leaves.
• To investigate the relationship between electrical impedance parameters and mango leaf age.
• To utilize a modified double-shell equivalent circuit model for data analysis.

Main Methods:

• Electrical impedance spectroscopy (EIS) was employed to measure impedance on mango leaves from six varieties.
• Leaves were sampled from different positions along the twig to represent varying ages.
• A modified double-shell equivalent circuit model was fitted to the impedance data.

Main Results:

• Nyquist plots indicated increasing charge transfer resistance with leaf age, shown by larger circular arc diameters.
• Fitting parameters R1 (resistance) increased, while C1 (capacitance) decreased systematically with leaf age.
• Strong correlations were observed between R1, C1, and leaf position, with high coefficients of determination in linear regression models.

Conclusions:

• Electrical impedance spectroscopy (EIS) is a rapid and reliable non-destructive method for assessing mango leaf physiological age.
• The parameters R1 and C1 derived from the equivalent circuit model serve as effective electrical indicators of leaf age.
• This technique holds potential for application in precision agriculture and plant phenotyping.