Description:FIELD OF THE INVENTION

[0001] The present invention relates to a system for non-destructive, in-field acoustic resistivity profiling of root-zone development in cereal or legume plants that is developed to monitor root growth dynamics across soil depths during repeated weekly measurements, thereby ensures improving plant phenotyping and selection in breeding operations.

BACKGROUND OF THE INVENTION

[0002] Demand for efficient and non-destructive methods to monitor root development throughout the full crop life cycle has increased significantly among plant breeders due to the need for improved drought tolerance and nutrient uptake traits in cereals and legumes. Conventional root phenotyping techniques typically rely on excavation, sampling, minirhizotron imaging, soil resistivity measurements, or indirect canopy-based indicators, which are often destructive, expensive, labor-intensive, time-limited, or require trained operators and provide only partial or late-stage information. In addition, existing means do not enable consistent, field-based determination of root isochrony, which represents the synchronized and uniform deepening of roots across soil layers and is strongly associated with drought escape and post-anthesis resource acquisition.

[0003] In traditional methods, root phenotyping in breeding programs relies on separate and independent methods such as excavation tools, minirhizotron imaging systems, soil electrical resistivity probes, and indirect canopy-based measurements that require significant field effort, specialized operators, and coordination between different data acquisition approaches. Field sampling and root extraction are performed manually or semi-manually, which disturbs the root zone and limits repeated observations over time. In addition, existing methods also involve high operational complexity and are often restricted to single time-point or short-duration assessments, reducing their ability to capture dynamic root development.

[0004] US10352916B2 disclose a system and method for accurate, field-ready, non-destructive, and three-dimensional plant root characterization using acoustic signals. The system is portable, fast, precise, and used in field conditions, including moist soil, to visualize root structure or mass distribution, without damaging growing crops. The system applied to characterize other underground objects, such as pipes, building foundations, archaeological artifacts, or mineral ores. During operation, the system generates a source acoustic signal. The system sends the source acoustic signal to an actuator acoustically coupled directly to a plant. The system obtains a response acoustic signal from an underground transducer monitoring a root of the plant. The system analyzes the response acoustic signal according to a model and based on the source acoustic signal. The system then determines, based on the analyzed response acoustic signal, a physical configuration of the plant root a system and method for accurate, field-ready, non-destructive, and three-dimensional plant root characterization using acoustic signals. The system is portable, fast, precise, and used in field conditions, including moist soil, to visualize root structure or mass distribution, without damaging growing crops.

[0005] WO2017091622A1 disclose an electronic sensor for detecting a root of a plant in soil, the electronic sensor that includes a first conductor plate configured to be disposed in soil, a switch, a power supply, and signal extractor. The switch is electrically coupled to the first conductor plate and is configured to switch between a first mode and a second mode. The power supply is electrically coupled to the switch and is configured to provide an electrical charge to the first conductor plate in the first mode of the switch. The signal extractor is electrically coupled to the switch and is configured to extract a signal response at the first conductor plate in the second mode of the switch. The present disclosure further provides a second conductor plate configured to be disposed in soil adjacent to and substantially parallel to the first conductor plate. The second conductor plate is electrically coupled to ground.

[0006] Conventionally, many systems for root phenotyping include excavation-based sampling, minirhizotron imaging, soil resistivity measurements, and indirect canopy indicators. However, these techniques are limited in providing continuous, non-destructive, in-field monitoring of root-zone development and often rely on destructive sampling, high-cost instrumentation, or short observation periods.

[0007] In order to overcome the aforementioned drawbacks, there exists a need in the art to develop a system that is capable of non-destructive, repeated in-field assessment of root-zone dynamics across the crop growth cycle. The required approach should enable depth-resolved characterization of root development. The system should provide reliable phenotyping and selection of plant varieties with improved drought adaptation and nutrient uptake efficiency for use in conventional breeding programs.

OBJECTS OF THE INVENTION

[0008] The principal object of the present invention is to overcome the disadvantages of the prior art.

[0009] An object of the present invention is to develop a system that is capable of non-destructive, in-field assessment of root-zone development in cereal and legume plants through acoustic-based profiling during repeated weekly measurements across growth stages.

[0010] Another object of the present invention is to develop a system that is capable of generating depth-resolved acoustic resistivity profiles and computing a quantitative Isochrony Score for evaluating synchrony of root deepening across soil layers.

[0011] Yet another object of the present invention is to develop a system that is capable of enabling reliable ranking and selection of plants or progeny based on Isochrony Score for advancement in conventional non-GMO breeding programs to improve drought adaptation and nutrient uptake efficiency.

[0012] The foregoing and other objects, features, and advantages of the present invention will become readily apparent upon further review of the following detailed description of the preferred embodiment as illustrated in the accompanying drawings.

SUMMARY OF THE INVENTION

[0013] The present invention relates to a system for non-destructive, in-field acoustic resistivity profiling of root-zone development in cereal or legume plants that is capable of capturing subsurface acoustic wave responses generated through controlled mechanical excitation and processing the resulting signals to obtain time-dependent soil resistivity characteristics. In addition, the system is further capable of evaluating temporal changes in root-zone structure to support consistent assessment of root development under field conditions.

[0014] According to an aspect of the present invention, a system for non-destructive, in-field acoustic resistivity profiling of root-zone development in cereal or legume plants, comprises of a calibrated impact hammer configured to deliver standardized mechanical impulses to a reference plate placed on a soil surface, each impulse having a predefined energy, duration, and waveform shape, a linear microphone array comprising a plurality of vertically or near-vertically oriented microphones or geophones arranged at predefined fixed spacing intervals along a vertical axis, said array positioned adjacent to the impact point on the soil surface at a fixed distance and configured to capture acoustic waveforms propagating through soil layers at a plurality of depths during each weekly measurement, the reference plate comprising a rigid, flat element placed on the soil surface directly adjacent to the plant stem, configured to receive impulses from the impact hammer and transmit acoustic energy into the underlying soil column, a signal processing unit operably connected to the microphone array, the signal processing unit configured to acquire the captured acoustic waveforms from each microphone in the array, apply band-pass filtering to remove ambient noise and isolate root-zone-relevant frequency bands, apply dispersion correction to compensate for frequency-dependent wave propagation in layered soil, apply soil-moisture correction to normalize acoustic data for varying volumetric water content across soil depths, invert the corrected waveforms to generate an Acoustic Resistivity Profile ARP(z,t), wherein z represents soil depth and t represents measurement time in weekly intervals.

[0015] According to another aspect of the present invention, the system further includes an Isochrony Score (IS) computation module operably connected to the signal processing unit, the IS computation module configured to, compute, for each soil depth layer z_i and each weekly time point t, the weekly change in acoustic resistivity as: ΔARP(z_i, t) = ARP(z_i, t) − ARP(z_i, t − 1), compute the mean weekly ARP derivative across all depth layers as dARP_mean/dt, compute a normalized cross-correlation between the weekly ARP derivative at each depth layer and the mean weekly ARP derivative, compute the Isochrony Score for each plant as: IS = (1/N) Σ_{i=1}^{N} Corr(dARP_i/dt, dARP_mean/dt), where N is the number of depth layers, and Corr denotes the normalized cross-correlation function, such that higher IS values indicate stronger synchrony of root deepening across soil layers, a computing system comprising a processor and a memory, operably connected to the signal processing unit and the IS computation module, the computing system configured to store the ARP profiles, IS values, and associated metadata, and to output a ranked list of plants or genotypes by IS value for breeding selection, the system is configured for repeated weekly deployment in the field from an early vegetative growth stage through post-anthesis without excavation or physical disturbance of the root zone.

[0016] While the invention has been described and shown with particular reference to the preferred embodiment, it will be apparent that variations might be possible that would fall within the scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where:
Figure 1 illustrates an isometric view of a system for non-destructive, in-field acoustic resistivity profiling of root-zone development in cereal or legume plants.

DETAILED DESCRIPTION OF THE INVENTION

[0018] The following description includes the preferred best mode of one embodiment of the present invention. It will be clear from this description of the invention that the invention is not limited to these illustrated embodiments but that the invention also includes a variety of modifications and embodiments thereto. Therefore, the present description should be seen as illustrative and not limiting. While the invention is susceptible to various modifications and alternative constructions, it should be understood, that there is no intention to limit the invention to the specific form disclosed, but, on the contrary, the invention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention as defined in the claims.

[0019] In any embodiment described herein, the open-ended terms "comprising," "comprises,” and the like (which are synonymous with "including," "having” and "characterized by") may be replaced by the respective partially closed phrases "consisting essentially of," consists essentially of," and the like or the respective closed phrases "consisting of," "consists of, the like.

[0020] As used herein, the singular forms “a,” “an,” and “the” designate both the singular and the plural, unless expressly stated to designate the singular only.

[0021] The present invention relates to a system for non-destructive, in-field acoustic resistivity profiling of root-zone development in cereal or legume plants that is developed to compute a quantitative Isochrony Score representing the synchrony of root deepening across soil layers. In addition, the system is further developed to rank plant genotypes based on Isochrony Score values and support selection of superior lines exhibiting improved drought adaptation and nutrient uptake efficiency for use in conventional breeding programs.

[0022] Referring to Figure 1, a block diagram of a system for non-destructive, in-field acoustic resistivity profiling of root-zone development in cereal or legume plants is illustrated, comprising a calibrated impact hammer 101, a linear microphone array 102, a reference plate 103, a signal processing unit 104, an Isochrony Score (IS) 105, a method 106 for non-destructive.

[0023] The system disclosed herein comprises a calibrated impact hammer 101 configured to deliver standardized mechanical impulses to a reference plate 103 positioned on a soil surface. The calibrated impact hammer 101 is configured to generate controlled acoustic excitation with predefined energy, duration, and waveform shape to ensure uniform signal generation during successive measurements. The calibrated impact hammer 101 further enables repeatable transmission of acoustic waves through different soil layers, thereby supporting consistent acquisition of subsurface acoustic response data for construction of acoustic resistivity profiles over time.

[0024] The impact hammer 101 comprises a piezoelectric actuator and an electromagnetic actuator configured to generate controlled mechanical impulses having an energy in the range of about 0.01 joules to about 5 joules and a pulse duration in the range of about 0.1 milliseconds to about 10 milliseconds. The piezoelectric actuator and the electromagnetic actuator enables standardized acoustic excitation for transmission of repeatable sound waves through soil layers during acoustic resistivity profiling measurements.

[0025] The piezoelectric actuator configured to operate through electromechanical deformation of a piezoelectric material. The piezoelectric actuator comprises a piezoelectric unit, an electrical excitation unit, a striker unit, and a supporting enclosure. The piezoelectric unit is configured to undergo dimensional deformation in response to an applied electrical signal received from the electrical excitation unit. The deformation generated within the piezoelectric unit is transferred to the striker unit to produce a controlled mechanical impact directed toward the reference plate 103 positioned on the soil surface.

[0026] The supporting enclosure maintains alignment and structural stability of the piezoelectric unit and striker unit during repeated operation. The actuator further supports rapid response operation with minimal mechanical variation, thereby ensuring repeatable acoustic excitation and consistent propagation of acoustic waves through different soil depths for generation of reliable acoustic resistivity profile data.

[0027] The electromagnetic actuator configured to generate controlled mechanical impulses for acoustic excitation. The electromagnetic actuator comprises a conductive coil unit, a magnetic core unit, a movable striker unit, a current supply unit, and a supporting enclosure. The conductive coil unit is configured to generate a magnetic field upon receiving electrical current from the current supply unit. The magnetic field interacts with the magnetic core unit to drive the movable striker unit toward an impact surface, thereby producing a controlled mechanical impulse directed toward the reference plate 103 positioned on the soil surface.

[0028] The supporting enclosure maintains guided movement and positional alignment of the movable striker unit during repeated operation. The electromagnetic actuator thereby enables controlled impulse energy and pulse duration for repeatable transmission of acoustic waves through subsurface soil layers during acoustic resistivity profiling.

[0029] A linear microphone array 102 comprising a plurality of vertically or near-vertically oriented microphones and geophones arranged at predefined spacing intervals along a vertical axis. The linear microphone array 102 is positioned adjacent to the impact point on the soil surface at a fixed distance and is configured to capture acoustic waveforms propagating through different soil layers during weekly measurement operations. The arrangement of the microphones or geophones along the vertical axis enables acquisition of acoustic response data corresponding to multiple subsurface depths for construction of acoustic resistivity profiles.

[0030] The linear microphone array 102 includes between 4 and 16 microphones and geophones arranged at spacing intervals of about 5 centimeters to about 20 centimeters along the vertical axis. The arrangement enables acquisition of acoustic response data from multiple subsurface depths during each measurement operation. The array covers a total vertical span of about 0.3 meters to about 2.0 meters beneath the soil surface, thereby allowing detection of acoustic wave propagation through different soil layers and root zones. The predefined spacing intervals and vertical coverage support generation of depth-dependent acoustic resistivity profiles and enable consistent monitoring of temporal changes in subsurface root development patterns.

[0031] The microphone array 102 consisting of a plurality of acoustic sensing units, a vertical support structure, a signal transmission unit, and a positioning frame. Each acoustic sensing unit is configured to detect pressure variations generated by propagation of acoustic waves through soil layers. The vertical support structure maintains predefined spacing intervals and orientation of the acoustic sensing units along the vertical axis.

[0032] The signal transmission unit transfers captured acoustic signals to a processing module for waveform analysis and profile construction. The positioning frame maintains a fixed distance between the microphone array 102 and the impact point during repeated weekly measurements. The microphone array 102 thereby enables acquisition of depth-dependent acoustic waveform data for generation of acoustic resistivity profiles.

[0033] The geophone array consisting of a plurality of geophone sensing units, a vertical alignment structure, a signal acquisition unit, and a mounting assembly. Each geophone sensing unit is configured to detect ground vibrations and particle motion generated by acoustic wave propagation through subsurface soil regions. The vertical alignment structure positions the geophone sensing units at predefined spacing intervals along the vertical axis to enable measurement across multiple soil depths.

[0034] The signal acquisition unit receives vibration signals from the geophone sensing units for further processing and inversion analysis. The mounting assembly maintains stable positioning of the geophone array adjacent to the impact location during measurement operations. The geophone array thereby enables consistent detection of subsurface acoustic responses for weekly acoustic resistivity profiling and root development analysis.

[0035] The reference plate 103 comprises a rigid, flat element positioned on the soil surface directly adjacent to the plant stem. The reference plate 103 is configured to receive controlled mechanical impulses generated by the impact hammer 101 and to transmit the resulting acoustic energy into the underlying soil column. The rigid structure of the reference plate 103 ensures uniform coupling of impact energy into the soil, minimizing energy loss and signal distortion. The reference plate 103 thereby facilitates consistent propagation of acoustic waves through different soil layers, enabling reliable acquisition of acoustic resistivity data for subsequent analysis and profiling.

[0036] The reference plate 103 has a diameter in the range of about 5 centimeters to about 20 centimeters and is composed of a rigid material selected from stainless steel, hardened aluminum, or engineering polymer. The selected materials provide sufficient mechanical strength and structural rigidity to ensure efficient transfer of impact energy into the soil surface. The defined diameter range enables effective coupling of acoustic impulses while maintaining localized excitation at the measurement point. The rigid construction ensures minimal deformation during repeated impacts, thereby supporting consistent transmission of acoustic waves into the soil column for reliable profiling measurements.

[0037] The impact hammer 101 and reference plate 103 are calibrated before each weekly measurement session using a calibration block having known acoustic impedance. The calibration block is configured to provide a reference medium with predefined and stable acoustic properties for standardization of measurement conditions. During calibration, controlled impacts are applied to the calibration block, and the resulting acoustic response is used to verify and adjust the energy output, waveform consistency, and signal transmission characteristics of the impact hammer 101 and reference plate 103. The impact hammer 101 and reference plate 103 ensures measurement repeatability, reduces experimental variability, and maintains accuracy in acoustic resistivity profiling across different sessions.

[0038] A signal processing unit 104 operably connected to the microphone array 102, the signal processing unit 104 being configured to acquire acoustic waveform signals captured by each microphone and geophone in the array. The signal processing unit 104 receives time-domain vibration data from multiple sensing points and organizes the acquired signals for further processing. The unit is further configured to synchronize the received signals, reduce noise components, and prepare the data for subsequent analysis, including transformation and profiling of acoustic responses corresponding to different soil depths during measurement operations.

[0039] The signal processing unit 104 is configured to apply band-pass filtering to the acquired acoustic waveform signals to remove ambient noise and isolate frequency bands relevant to root-zone acoustic responses. The band-pass filtering process is configured to retain only selected frequency components associated with subsurface wave propagation while attenuating low-frequency environmental disturbances and high-frequency electrical and mechanical noise. This filtering enhances signal clarity and improves the accuracy of subsequent acoustic resistivity profiling. The processed signals thereby represent depth-sensitive acoustic information required for reliable interpretation of soil and root interaction dynamics during measurement operations.

[0040] The signal processing unit 104 is also configured to apply dispersion correction to the filtered acoustic signals to compensate for frequency-dependent wave propagation occurring within layered soil structures. The dispersion correction process adjusts phase and velocity distortions introduced due to variation in soil density, moisture content, and mechanical properties across different depths. This correction enables accurate alignment of acoustic wave components across frequencies, ensuring faithful representation of subsurface propagation behavior. The resulting corrected signals improve consistency of acoustic resistivity profiling and enhance reliability of depth-resolved interpretation of soil and root zone characteristics during measurement operations.

[0041] The signal processing unit 104 is further configured to apply soil-moisture correction to the processed acoustic signals to normalize variations arising from differing volumetric water content across soil depths. The soil-moisture correction process compensates for changes in acoustic wave attenuation and velocity caused by moisture-dependent alterations in soil mechanical properties. This normalization ensures that variations in measured acoustic responses are attributed primarily to structural and root-related changes rather than moisture fluctuations. The corrected data thereby provides improved consistency and reliability in acoustic resistivity profiling across temporal measurements and varying field conditions during analysis.

[0042] The signal processing unit 104 is also further configured to invert the corrected acoustic waveforms to generate an Acoustic Resistivity Profile, denoted as ARP(z,t), wherein z represents soil depth and t represents measurement time in weekly intervals. The inversion process converts time-domain acoustic signals into depth-resolved resistivity information by mapping signal amplitude, phase, and travel characteristics to corresponding subsurface layers. The generated ARP(z, t) provides a time-series representation of acoustic resistivity variations across soil depths, enabling visualization of temporal changes in subsurface conditions and supporting subsequent computation of root-related structural dynamics during analysis.

[0043] An Isochrony Score 105 (IS) computation module operably connected to the signal processing unit 104, the IS computation module being configured to compute depth-resolved temporal dynamics of acoustic resistivity data for assessment of root growth synchrony. the IS computation module is configured to compute, for each soil depth layer zᵢ and each weekly time point t, the weekly change in acoustic resistivity as ΔARP(zᵢ,t) = ARP(zᵢ,t) − ARP(zᵢ,t−1). The computation determines the temporal difference between successive weekly acoustic resistivity values at each depth layer.

[0044] The operation quantifies the rate of change in subsurface acoustic properties over time, enabling detection of dynamic variations in soil structure and root-zone activity across consecutive measurement intervals for further analysis in Isochrony Score 105 evaluation. the mean weekly derivative of acoustic resistivity across all soil depth layers, denoted as dARP_mean/dt. The computation aggregates the individual depth-wise derivatives and calculates their average value for each weekly time point, representing the overall temporal trend of acoustic resistivity variation.

[0045] The IS computation module is configured to compute a normalized cross-correlation between the weekly derivative of acoustic resistivity at each soil depth layer and the mean weekly derivative across all depth layers. The normalized cross-correlation quantifies the degree of similarity in temporal variation patterns between individual depth-specific signals and the overall averaged signal. This operation enables assessment of how closely each soil layer follows the collective dynamic behavior of the root zone over time, thereby capturing synchronization characteristics of subsurface changes across different depths during sequential weekly measurements.

[0046] The IS computation module is further configured to compute the Isochrony Score 105 for each plant using the expression IS = (1/N) Σᵢ₌₁ⁿ Corr(dARPᵢ/dt, dARP_mean/dt), where N represents the total number of soil depth layers and Corr denotes the normalized cross-correlation function. The computation aggregates correlation values across all depth layers to obtain a single scalar score representing overall synchrony. Higher Isochrony Score 105 values indicate stronger temporal alignment of acoustic resistivity changes across soil depths, reflecting more uniform root deepening behavior and coordinated subsurface development patterns during weekly measurement intervals.

[0047] A computing system comprising a processor and a memory is operably connected to the signal processing unit 104 and the Isochrony Score 105 computation module. The computing system stores Acoustic Resistivity Profile data, Isochrony Score 105 values, and associated measurement metadata for each plant over successive weekly intervals. The system processes the stored data to generate a ranked list of plants or genotypes based on Isochrony Score 105 values for selection in breeding. The arrangement is configured for repeated weekly field deployment from early vegetative stages through post-anthesis without excavation or physical disturbance of the root zone, thereby maintaining natural growth conditions during measurements.

[0048] A method 106 for non-destructive, in-field root isochrony phenotyping and breeding selection in cereal and legume plants. The method 106 comprising identifying a plurality of plants at a defined growth stage and establishing a weekly measurement schedule spanning from an early vegetative stage to a post-anthesis stage, the schedule comprising measurements at approximately weekly intervals.

[0049] The identification step is configured to select plants for systematic field evaluation under natural conditions. The defined growth stage provides a standardized reference for initiating observations. The weekly interval schedule enables consistent and time-resolved acquisition of data across the growth cycle. This structured approach supports uniform monitoring of root development dynamics and facilitates comparative analysis across successive time points.

[0050] The method 106 further includes at each weekly measurement, performing the following steps at each of the plurality of plants. Placing a reference plate 103 on the soil surface adjacent to the plant stem, the reference plate 103 being configured to ensure uniform coupling of mechanical energy into the underlying soil. Delivering one or more standardized mechanical impulses to the reference plate 103 using a calibrated impact hammer 101, the impulses being configured to generate repeatable acoustic excitation with controlled energy and waveform characteristics for consistent propagation through soil layers.

[0051] Capturing acoustic waveforms propagating through the soil column using a linear microphone array positioned at a fixed distance from the impact point, the array comprising a plurality of microphones or geophones arranged at predefined vertical spacing intervals. The array is configured to detect depth-resolved acoustic responses from subsurface layers, enabling acquisition of time-synchronized waveform data corresponding to different soil depths for further processing and analysis.

[0052] The method 106 also includes processing of each captured waveform by applying band-pass filtering to isolate frequency components relevant to root-zone acoustic responses. The band-pass filter is configured to allow a selected range of frequencies associated with subsurface wave propagation while attenuating low-frequency environmental noise and high-frequency instrumental disturbances.

[0053] The method 106 ensures improved signal clarity for subsequent analysis. Thereafter, dispersion correction is applied to compensate for frequency-dependent wave propagation effects in layered soil, followed by soil-moisture correction to normalize variations caused by volumetric water content differences across depths. The corrected waveforms are then inverted to generate an Acoustic Resistivity Profile, ARP(z,t), wherein z represents soil depth and t represents weekly measurement time. The ARP representation provides depth-resolved and time-resolved characterization of subsurface acoustic properties for further evaluation.

[0054] The method 106 also includes computing the weekly change in acoustic resistivity at each soil depth layer as ΔARP(zᵢ,t) = ARP(zᵢ,t) − ARP(zᵢ,t−1), the computation quantifies temporal variation in subsurface acoustic properties at successive weekly intervals. This enables tracking of depth-wise changes in soil–root interaction over time. Computing an Isochrony Score 105 (IS) for each plant as IS = (1/N) Σᵢ₌₁ᴺ Corr(dARPᵢ/dt, dARP_mean/dt), wherein N is the number of soil depth layers, dARPᵢ/dt represents the weekly derivative of acoustic resistivity at depth layer i, dARP_mean/dt represents the mean weekly derivative across all depth layers, and Corr denotes the normalized cross-correlation function. The Isochrony Score 105 quantifies the degree of synchrony in temporal changes across soil depths.

[0055] In which Ranking the plants by Isochrony Score 105 value, higher scores indicate stronger coordination of root-related subsurface changes across soil layers. Selecting one or more plants or progeny exhibiting highest Isochrony Score 105 values for advancement in a conventional non-GMO breeding pipeline. The selected materials are advanced to produce varieties exhibiting improved root isochrony, associated with enhanced drought escape behavior and improved post-anthesis nutrient uptake efficiency under field conditions.

[0056] The early vegetative stage corresponds to the V3 stage, and the post-anthesis stage corresponds to the R5 stage, weekly measurements are performed at approximately 7-day intervals spanning from V3 to R5. The defined growth stages provide a standardized framework for initiating and terminating field measurements across the crop development cycle. The 7-day interval ensures consistent temporal resolution of data acquisition, enabling uniform tracking of root development dynamics. The V3 to R5 span captures both early vegetative growth and reproductive development phases, supporting comprehensive assessment of subsurface root behavior and temporal progression.

[0057] After computing the Isochrony Score 105, the plants are classified based on the degree of synchrony in root deepening behavior across soil layers. A high-isochrony group comprises plants having an Isochrony Score 105 in the range of about 0.75 to about 1.00, indicating strongly synchronized temporal changes in acoustic resistivity across depth layers. This reflects uniform and coordinated root development, and such plants are considered suitable for advancement or use in crossing programs. A moderate-isochrony group comprises plants having an Isochrony Score 105 in the range of about 0.50 to about 0.74, indicating partial synchronization of root growth dynamics.

[0058] These plants exhibit intermediate stability and are suitable for further evaluation, retesting, or re-ranking in subsequent selection cycles. A low-isochrony group comprises plants having an Isochrony Score 105 below about 0.50, indicating weak or asynchronous root deepening behavior across soil layers. Such plants are considered unsuitable for advancement with respect to root isochrony traits and are excluded from further selection in the breeding pipeline.

[0059] The plant is selected from the group consisting of rice (Oryza sativa), wheat (Triticum aestivum), maize (Zea mays), sorghum (Sorghum bicolor), barley (Hordeum vulgare), oat (Avena sativa), and soybean (Glycine max). These plants represent major cereal and legume crops widely cultivated for food, feed, and industrial applications. The selection enables application of the method 106 across diverse agronomic species with varying root architectures and growth patterns. Inclusion of both monocot and dicot species allows evaluation of root isochrony traits under different physiological and environmental conditions.

[0060] Selecting one or more plants for advancement comprises ranking parents within each maturity group by Isochrony Score 105 (IS) value, each parent is evaluated based on the degree of synchrony in root development across soil layers. This enables comparative assessment within similar maturity classes. Selecting the highest-IS parents for conventional crossing, plants exhibiting superior root synchrony are chosen as breeding material to combine favorable traits through non-genetic hybridization approaches.

[0061] Screening segregating progeny populations by repeating the measurement and analysis steps on progeny plants and selecting progeny with IS at or above a predefined advancement threshold, ensuring retention of strong root isochrony traits in successive generations. Advancing selected progeny through multi-environment field trials while maintaining high IS alongside yield and quality selection criteria, enabling evaluation of trait stability across varying environmental and climatic conditions and releasing a variety having confirmed high IS, stable yield across variable rainfall conditions, and improved post-anthesis nutrient uptake, all steps are performed without genetic modification, ensuring that selection is achieved through conventional breeding and phenotypic evaluation methods based on root isochrony performance.

[0062] The present invention works best in the following manner, where the plurality of plants at the defined growth stage are first identified and a weekly measurement schedule is established spanning from an early vegetative stage to the post-anthesis stage, with measurements performed at approximately weekly intervals. At each weekly interval, the reference plate 103 is placed on the soil surface adjacent to the plant stem, and one or more standardized mechanical impulses are delivered to the reference plate 103 using the calibrated impact hammer 101. The generated acoustic waves are transmitted into the soil column and are captured by the linear microphone array 102 positioned at the fixed distance from the impact point, the array comprising a plurality of microphones and geophones arranged at predefined vertical spacing intervals to obtain depth-resolved acoustic responses. The captured acoustic waveforms are then processed by the signal processing unit 104, band-pass filtering is first applied to remove ambient noise and isolate root-zone-relevant frequency bands, followed by dispersion correction to compensate for frequency-dependent wave propagation in layered soil.

[0063] In continuation, the Soil-moisture correction is then applied to normalize variations in volumetric water content across soil depths, after which the corrected waveforms are inverted to generate the Acoustic Resistivity Profile, ARP(z,t). The temporal variation in acoustic resistivity is computed at each depth layer as ΔARP(zᵢ,t) = ARP(zᵢ,t) − ARP(zᵢ,t−1), and the mean weekly derivative across all depth layers is determined. The Isochrony Score 105 computation module then computes the normalized cross-correlation between the weekly ARP derivative at each depth layer and the mean weekly ARP derivative, and calculates the Isochrony Score 105 as IS = (1/N) Σ Corr(dARPᵢ/dt, dARP_mean/dt). Higher Isochrony Score 105 values indicate stronger synchrony of root deepening across soil layers. The computed Isochrony Score 105 values are then used by the computing system to rank plants or genotypes, and the highest-ranking selections are advanced through the conventional non-GMO breeding pipeline. The entire process is executed through repeated weekly field deployment from early vegetative stage through post-anthesis without excavation or physical disturbance of the root zone, thereby enabling continuous, The method 106 for non-destructive phenotyping and selection based on root isochrony performance.

[0064] Although the field of the invention has been described herein with limited reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternate embodiments of the invention, will become apparent to persons skilled in the art upon reference to the description of the invention. , Claims:1) A system for non-destructive, in-field acoustic resistivity profiling of root-zone development in cereal or legume plants, comprising:

i) a calibrated impact hammer 101 configured to deliver standardized mechanical impulses to a reference plate 103 placed on a soil surface, each impulse having a predefined energy, duration, and waveform shape;
ii) a linear microphone array 102 comprising a plurality of vertically or near-vertically oriented microphones or geophones arranged at predefined fixed spacing intervals along a vertical axis, said array positioned adjacent to the impact point on the soil surface at a fixed distance and configured to capture acoustic waveforms propagating through soil layers at a plurality of depths during each weekly measurement;
iii) the reference plate 103 comprising a rigid, flat element placed on the soil surface directly adjacent to the plant stem, configured to receive impulses from the impact hammer 101 and transmit acoustic energy into the underlying soil column;
iv) a signal processing unit 104 operably connected to the microphone array 102, the signal processing unit 104 configured to:
a) acquire the captured acoustic waveforms from each microphone in the array;
b) apply band-pass filtering to remove ambient noise and isolate root-zone-relevant frequency bands;
c) apply dispersion correction to compensate for frequency-dependent wave propagation in layered soil;
d) apply soil-moisture correction to normalize acoustic data for varying volumetric water content across soil depths; and
e) invert the corrected waveforms to generate an Acoustic Resistivity Profile ARP(z,t), wherein z represents soil depth and t represents measurement time in weekly intervals;
v) an Isochrony Score 105 (IS) computation module operably connected to the signal processing unit 104, the IS computation module configured to:
a) compute, for each soil depth layer z_i and each weekly time point t, the weekly change in acoustic resistivity as;
ΔARP(z_i, t) = ARP(z_i, t) − ARP(z_i, t − 1);
b) compute the mean weekly ARP derivative across all depth layers as dARP_mean/dt;
c) compute a normalized cross-correlation between the weekly ARP derivative at each depth layer and the mean weekly ARP derivative; and
d) compute the Isochrony Score 105 for each plant as:
IS = (1/N) Σ_{i=1}^{N} Corr(dARP_i/dt, dARP_mean/dt), where N is the number of depth layers, and Corr denotes the normalized cross-correlation function, such that higher IS values indicate stronger synchrony of root deepening across soil layers; and
e) a computing system comprising a processor and a memory, operably connected to the signal processing unit 104 and the IS computation module, the computing system configured to store the ARP profiles, IS values, and associated metadata, and to output a ranked list of plants or genotypes by IS value for breeding selection,
wherein the system is configured for repeated weekly deployment in the field from an early vegetative growth stage through post-anthesis without excavation or physical disturbance of the root zone.

2) The system of Claim 1, wherein the linear microphone array 102 comprises between 4 and 16 microphones or geophones spaced at intervals of about 5 centimeters to about 20 centimeters along the vertical axis, the array covering a total vertical span of about 0.3 meters to about 2.0 meters beneath the soil surface.

3) The system of Claim 1, wherein the impact hammer 101 comprises a piezoelectric or electromagnetic actuator configured to deliver impulses with an energy in the range of about 0.01 joules to about 5 joules and a duration in the range of about 0.1 milliseconds to about 10 milliseconds.

4) The system of Claim 1, wherein the reference plate 103 has a diameter in the range of about 5 centimeters to about 20 centimeters and is composed of a rigid material selected from stainless steel, hardened aluminum, or engineering polymer.

5) The system of Claim 1, wherein the impact hammer 101 and reference plate 103 are calibrated before each weekly measurement session using a calibration block with known acoustic impedance.

6) A method 106 for non-destructive, in-field root isochrony phenotyping and breeding selection in cereal or legume plants, the method 106 comprising:

a) identifying a plurality of plants at a defined growth stage and establishing a weekly measurement schedule spanning from an early vegetative stage to a post-anthesis stage, said schedule comprising measurements at approximately weekly intervals;
b) at each weekly measurement, performing the following steps at each of the plurality of plants:
i) placing a reference plate 103 on the soil surface adjacent to the plant stem;
ii) delivering one or more standardized mechanical impulses to the reference plate 103 using a calibrated impact hammer 101; and
iii) capturing acoustic waveforms propagating through the soil column using a linear microphone array 102 positioned at a fixed distance from the impact point, the array comprising a plurality of microphones or geophones at predefined vertical spacing intervals;
c) processing each captured waveform by applying band-pass filtering to isolate root-zone-relevant frequency bands, applying dispersion correction for frequency-dependent wave propagation in layered soil, applying soil-moisture correction to normalize for volumetric water content variation and inverting the corrected waveforms to generate an Acoustic Resistivity Profile ARP(z,t), wherein z represents soil depth and t represents the weekly measurement time;
d) computing the weekly change in acoustic resistivity at each soil depth layer as ΔARP(z_i, t) = ARP(z_i, t) − ARP(z_i, t − 1);
e) computing an Isochrony Score 105 (IS) for each plant as IS = (1/N) Σ_{i=1}^{N} Corr(dARP_i/dt, dARP_mean/dt), where N is the number of soil depth layers, dARP_i/dt is the weekly ARP derivative at depth layer i, dARP_mean/dt is the mean weekly ARP derivative across all depth layers, and Corr denotes the normalized cross-correlation function;
f) ranking the plants by IS value; and
g) selecting one or more plants or progeny with the highest IS values for advancement in a conventional non-GMO breeding pipeline to produce varieties exhibiting improved root isochrony associated with enhanced drought escape or post-anthesis nutrient uptake.

7) The method of Claim 2, wherein the early vegetative stage is the V3 stage and the post-anthesis stage is the R5 stage, and wherein weekly measurements are performed at approximately 7-day intervals spanning from V3 to R5.

8) The method of Claim 2, wherein after computing the Isochrony Score 105, the plants are classified into a high-isochrony group having an IS in the range of about 0.75 to about 1.00, indicating strongly synchronized root deepening across soil layers, suitable for advancement or crossing, a moderate-isochrony group having an IS in the range of about 0.50 to about 0.74, indicating partial synchronization, suitable for retesting or re-ranking and a low-isochrony group having an IS below about 0.50, indicating weak or asynchronous root deepening, excluded from further advancement for root isochrony traits.

9) The method of Claim 2, wherein the plant is selected from the group consisting of: rice (Oryza sativa), wheat (Triticum aestivum), maize (Zea mays), sorghum (Sorghum bicolor), barley (Hordeum vulgare), oat (Avena sativa), and soybean (Glycine max).

10) The method of Claim 2, wherein selecting one or more plants for advancement comprises:

a) ranking parents within each maturity group by IS value;
b) selecting the highest-IS parents for conventional crossing;
c) screening segregating progeny populations by repeating steps on progeny plants and selecting progeny with IS at or above a predefined advancement threshold;
d) advancing selected progeny through multi-environment field trials while maintaining high IS alongside yield and quality selection criteria; and
e) releasing a variety having a confirmed high IS, stable yield across variable rainfall conditions, and improved post-anthesis nutrient uptake, wherein all steps are performed without genetic modification.