WO2018096542A1

WO2018096542A1 - A field pesticide system and a method for eliminating pests

Info

Publication number: WO2018096542A1
Application number: PCT/IL2017/051287
Authority: WO
Inventors: Nadav BITTON; Hanokh Czosnek; Sharoni Shafir
Original assignee: Yissum Research Development Co of Hebrew University of Jerusalem
Current assignee: Yissum Research Development Co of Hebrew University of Jerusalem
Priority date: 2016-11-27
Filing date: 2017-11-26
Publication date: 2018-05-31
Anticipated expiration: 2019-05-27
Also published as: IL249243A0; IL249243B

Abstract

The present invention discloses an antenna array comprising a plurality of antenna elements comprising leaky feeder elements configured and operable to emit RF radiation in a controllable manner. The antenna array is configured and operable for extending along target field/greenhouse/net house sites to treat pest infestation at certain locations. The antenna array and the systems and methods of the present invention utilize the properties of electro-magnetic fields to harm the entire life cycle of the pest, from egg to flying adult.

Description

A FIELD PESTICIDE SYSTEM AND A METHOD FOR ELIMINATING

PESTS

TECHNOLOGICAL FIELD

The present invention relates to the field of prevention of infestation of agricultural crops by pests.

BACKGROUND ART

References considered to be relevant as background to the presently disclosed subject matter are listed below:

- US 2003/215354

- US 1,981,583

- US 3,307,289

- US 3,699,976

- US 3,877,401

- US 3,902,273

- US 4,039,795

- US 4,366,644

- US 4,873,789

- US 5,060,414

- US 5,058,313

- US 5,141,059

- US 5,271,470

- US 5,287,818

- US 5,468,938

- US 5,950,362

- US 5,968,401

- US 6,185,865

- US 6,192,622

- US 6,195,936

- US 6,237,278

- US 6,250,011 - US 6,320, 197

- US 6,453,609

- US 8,943,744

Acknowledgement of the above references herein is not to be inferred as meaning that these are in any way relevant to the patentability of the presently disclosed subject matter.

BACKGROUND

Agricultural crops are under constant threat of pathogens, some of them transmitted by flying insects such as the whitefly Bemisia tabaci and the thrips Frankliniella occidentalis. The whitefly B. tabaci, for instance, is a major and widespread insect pest because it causes feeding damage to important crops, such as vegetables, cotton, tobacco, ornamental plants, aromatic herbs, and others. Additionally, it transmits viruses to many plants, such as vegetables, staple crops, ornamental plants, cotton and tobacco. For example, the whitefly is known to transmit the Tomato yellow leaf curl virus (TYLCV) to tomato plants and thrips to transmit Tomato spotted wilt (TSWV) to tomato and diverse vegetables and to ornamental plants. Estimates of the worldwide cost of direct damage arising from the whitefly, is believed to be in the order of at least one billion dollars annually, and the whitefly is only one of numerous flying insect pests causing such damage.

Attempts to control such insect pests in commercial settings (fields, greenhouses) include: (i) the use of insecticide sprays, which causes collateral damage to the environment and to other beneficial insects such as bees, and even leads to the development of resistant populations of the targeted pest insects; (ii) the use of natural enemies of the pest, but this is (partially) effective only in closed environments such as greenhouses; (iii) the protection of crops grown in open fields with nets is not practical for extensive agriculture; the growth of plants in hermetically closed greenhouses/net houses is an expensive alternative; and (iv) ultrasonic sound waves have been applied experimentally to act as a repellant on insects, though not as a pesticide. This has been shown to be useful for repelling mosquitoes, ants, spiders, cockroaches, flies, fleas, ticks, crickets, bees, and moths. Frequencies of up to 200 kHz are effective, though it has been shown that frequencies even in the audio region may also be effective. Ultrasonic sound waves have not been shown to be effective against insect pests in agriculture. International Publication application No. WO 06/027005 relates to a method for destroying locusts, comprising at least the following steps: determination of the zones, in which the female locusts lay their eggs; determination of whether eggs have been laid in the zone; irradiation and destruction of at least part of the laid eggs using microwaves. This international publication application also relates to a device for carrying out the method.

There therefore exists a need for the control of the deleterious effects of insect pests, which overcomes at least some of the disadvantages of prior art systems and methods.

GENERAL DESCRIPTION

The present disclosure describes new antenna array system and method for controlling insect pest infestations, by the use of Radio Frequency (RF) radiation applied to the regions of the plants which the pests infest. The term "RF radiation" generally refers herein below to any of the electromagnetic wave frequencies that lie in the range extending from around 3 kHz to 300 GHz, which include those frequencies used in radio communication or radar. According to a broad aspect of the present invention, there is provided an antenna array comprising a plurality of antenna elements comprising leaky feeder elements configured and operable to emit RF radiation in a controllable manner. The antenna array is configured and operable for extending along target field/greenhouse/net house sites to treat pest infestation at certain locations. The technique of the present invention utilize the properties of electro-magnetic fields to harm the entire life cycle of the pest, from egg to flying adult. The system of the present invention is aimed at protecting any agricultural crop, including vegetables, ornamental plants, fruits, etc. from any nuisance and pest above ground and underground, including sucking and herbivore insects, fungi, nematodes, bacteria etc., presently known and unknown, and to be discovered, that transmit disease or cause feeding damage and threat yield, or are neutral to the crop at present but may constitute a threat in the future by any kind of selection, mutation, recombination, etc. The technique of the present invention are configured for greenhouses as well as open fields. The antenna array may be stationary or may be moved from greenhouse to greenhouse.

Microwave and Radio Frequency (RF) radiation causes dielectric heating, primarily by absorption of energy in water. Many adult insect pests have an open blood system and their total body weight consists of 50% to 90% water, depending on the species, making them extremely vulnerable to heat induced by electro-magnetic radiation. On the other hand, insects use cuticle and wax to protect their body from environmental potentially deleterious stresses. The insect egg is also extremely venerable, because it is protected by a very thin membrane and contains mostly liquids. The inventors of the present invention have found that the surface power density of RF radiation should be applied at a certain level such that it prevents any deleterious effect of the pests on the plant, and impairs the flight and movement of the insect to a few minutes at most. The level of the RF field has to be carefully controlled so that it fulfills its function in curbing pest infestation, but, at the same time, is low enough not to cause collateral damage to the plant as well as pollinating bees and other beneficial insects, such as natural enemies. Furthermore, RF radiation should be at a level which has no particular effect on the plant tissues on which it is applied, especially on the plant flowering or fruit setting. It should be understood that the surface power density of the RF radiation should be determined to harm pests, but also to preserve the environment. Therefore, the present invention enables complying with both the plants' and the pests' life cycle.

In some embodiments, the leaky feeder elements are configured and operable to support plants extending along the target field site.

In some embodiments, the plurality of antenna elements comprises four antenna elements, each element being arranged in the array to emit radiation in a different direction such that the target field site is exposed to radiation.

In some embodiments, the different types of pests comprise pests at all stages of metamorphosis, their eggs, and viruses they carry.

In some embodiments, the antenna array is placed inside the ground of a target field site to be treated.

In some embodiments, the antenna array further comprises a control unit being configured and operable to control the Radio Frequency (RF) energy.

In some embodiments, the control unit is configured and operable to produce Radio Frequency (RF) energy generating at least one of a magnetic field having a surface power density having an electric field strength in the range of about 5 V/m to 50,000 V/m and an electromagnetic field having a surface power density in the range of about 10 mWatt/m² to 8000 mWatt/m². In some embodiments, the surface power density is in the range of about 20 mW/m² to 1000 mW/m². The RF field may be a Continuous Wave (CW) field, or a pulsed field having substantially higher peak powers than its average power level. Different pests may be affected differently by the use of CW or pulsed fields, depending on whether the effect on those species is due solely to dielectric heating, or whether the higher peak powers and modulated fields of pulsed transmissions have a more specific physiological effect on the tissues or the biological system of the pests. Furthermore, the frequency of the RF field used may need to be selected for optimum effectiveness, though cost of generation of the RF field may be a more important parameter than the exposure effectiveness. The radio frequency energy may have a frequency within a standard telecommunications band, such that commonly available control unit chip sets may be used. This is especially so since components chip sets for commonly used RF applications, such as for DECT (Digital Enhanced Cordless Telecommunications) transceivers are widely available at very low cost, and because large areas will need to be covered in order to make the technology effective, the cost of the RF transmitters must be kept as low as possible. This commercial and economic consideration may mandate the use of one of the standard mobile phone frequency bands, such as the 2.4 or 5.8 GHz bands, even if a higher frequency may be more effective as a pesticide transmission. For example, the antenna elements may be simple RF oscillator circuits, without any signal modulation facilities, and possibly even without any frequency stabilization if permitted by the regulatory authorities.

According to another broad aspect of the present invention, there is provided a field pesticide system comprising a control unit being configured and operable to produce Radio Frequency (RF) energy having different modes corresponding to different types of pests to be treated and an antenna array connected to the control unit wherein the antenna array comprises a plurality of antenna elements generating Radio Frequency (RF) radiation. Each mode comprises at least one of the following parameters: a certain level of energy to be emitted, a certain duration of the emission of the energy, a certain periodicity of repetition of the emission, and a certain type of modulation. The control unit is configured and operable to control different modes corresponding to different types of pests to be treated and to generate a different time pattern accordingly. The control unit is connected to the plurality of antenna elements and is configured and operable for controlling the RF radiation. The plurality of antenna elements comprises leaky feeder elements configured and operable to emit the RF radiation. The antenna array is configured and operable as described above. The control unit may control the RF energy to be in a Continuous Wave (CW) form or pulsed.

The control unit of the present invention may be integrated with the antenna array or may be a separate entity located remotely to the array antenna.

In some embodiments, the control unit comprises an amplifier connected to each leaky feeder element and configured and operable to amplify an intensity signal outputted to the leaky feeder element.

The technique of the present invention is effective on every insect (e.g. pest insects), fungus and bacteria (and the pathogen they may carry, such as viruses), which land on plants or settle near the plant roots, for times ranging from minutes to days, making them extremely vulnerable to RF radiation applied in the close vicinity of those plants. If it is known at what stage of development of the plant the insects have already laid their eggs, it may also be possible to start the eradication process on the eggs, even if the insects themselves have already left the plant. Such insect agricultural pests may include aphids, thrips, and mealybugs, which land and breed on plants. However, the technique of the present invention are equally applicable to animal or human insect pests, in which case the RF field may attempt to eradicate them by application in their breeding grounds, such as in marshes, or on the banks of standing water, and ponds.

In order to be effective over large agricultural areas, the RF field must be deployable using a low cost, simple delivery system, since the surface to be treated may be substantial. The form of transmitting antenna elements used must be such as to remain reasonably matched to the RF feed line over the whole protection time span, so that the field strength remains above the level at which the RF is effective as an insecticide. A simple vertically disposed rod antenna element can also serve as a plant support rod, thereby saving the need for separate support for this function. Alternatively, the antenna element can be in the form of a wire-based or ribbon-based array running along the length of a row of plants, having coaxial or strapline feeder cables running to each antenna location. It is also possible to provide a mobile RF treatment boom or trestle that could spread over the whole region of a field in the same way as mobile sprinkler systems cover a field. By this means, only a limited number of RF transmitter units are required, since that same number of transmitter units is conveyed across the whole field by a mobile conveyer platform. The effect of the RF field may be limited to a meter or more wide ribbon, and the travelling antenna array may be stopped at predetermined positions for a predetermined time over rows of plants, to enable the RF field to implement its effects at each row of plants; in this manner, the motion of the distributed RF transmission array could cover a complete field.

In some embodiments, the antenna array is placed above the ground of the target field site or at least partially inside the ground of the target field site.

In some embodiments, the antenna array is solar powered.

According to another broad aspect of the present invention, there is provided a method for eliminating pests comprising generating Radio Frequency (RF) radiation having a surface power density in the range of about 10 mWatt/m² to about 8000 mWatt/m² along a target field site to be treated for pesticide infestation at certain locations.

In some embodiments, generating the Radio Frequency (RF) radiation comprises placing an antenna array above the ground of the target field site or at least partially inside the ground of the target field site. The method may comprise arranging leaky feeder elements above the ground of the target field site or at least partially inside the ground of the target field site.

In some embodiments, generating the Radio Frequency (RF) radiation comprises producing Radio Frequency (RF) energy at different modes corresponding to different types of pests to be treated; each mode comprises at least one of the following parameters: a certain level of energy to be emitted, a certain duration of the emission of the energy, a certain periodicity of repetition of the emission, and a certain type of modulation.

In some embodiments, duration of the emission of the energy does not exceed 20 minutes to prevent the pests from delivering their virus.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to better understand the subject matter that is disclosed herein and to exemplify how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:

Fig. 1A is a schematic view of an antenna array according to some embodiments of the present invention; Fig. IB is a schematic partial view of the control unit according to some embodiments of the present invention;

Fig. 1C shows a view of a field of tomato plants arranged in ordered rows, with the individual plants supported by support rods, and with individual RF transmitting antenna elements arranged on the support rods at a predetermined height;

Fig. ID is a schematic view of an antenna array according to another embodiment of the present invention;

Fig. 2 is a schematic view of a non-limiting example of a field pesticide system according to some embodiments of the present invention;

Fig. 3A is a schematic illustration of an alternative implementation to that of

Fig. 2, in which the RF power can be controlled at a remote RF control unit;

Fig. 3B is a picture of another alternative implementation to that of Fig. 2, in which the RF power can be controlled at a remote RF control unit;

Fig. 4 is a schematic illustration of another alternative implementation, in which a self-propelled traveling boom system is used;

Fig. 5A is a schematic illustration of another alternative implementation of the antenna array of the present invention, according to some embodiments of the present invention; and

Fig. 5B represents a comparison of pest presence by using the system of the present invention versus prior art techniques.

DETAILED DESCRIPTION OF EMBODIMENTS

The inventors of the present invention have developed a novel technique for eliminating pests by generating Radio Frequency (RF) radiation at a certain selected range enabling to efficiently eradicate different type of pests without harming the environment, including plants and animals. Generating RF radiation along a target field site at certain locations, treats pesticide infestation.

Reference is made to Fig. 1A illustrating an antenna array 100 deployed on a target field site to be treated for pesticide infestation at certain locations. The antenna array 100 comprises a plurality of antenna elements 102 extending along the target field site and generating Radio Frequency (RF) radiation, and configured and operable for running to the certain locations in the array. Although for the sake of simplicity, in this non-limiting example, the antenna array is illustrated as antenna elements positioned perpendicularly respectively to the ground and having each antenna element positioned adjacent to a tree, the present invention is not limited to such configuration. The antenna elements may be positioned in any convenient manner respectively to the ground (pe endicular/parallel/forming any angle). Moreover, the number and the position of the antenna elements with respect to the plants/trees to be treated depend on the length of the antenna elements and on the intensity of the RF energy emitted by the antenna elements. A plurality of plants may be irradiated by a single antenna element. Furthermore, although in this example, the antenna elements are partially inserted inside the ground of the target field site, the present invention is not limited to such configuration. The antenna elements may be placed above the ground of the target field site, at least partially inside the ground of the target field site or inside the ground of a target field site to be treated.

In some embodiments, the antenna elements 102 comprise leaky feeder cables and the antenna array 100 comprises a control unit 104 which may be directly connected to each antenna element of the plurality of antenna elements 102 or to a plurality of antenna elements and being configured and operable for providing an input signal to the leaky feeder cables and for controlling the RF radiation. More specifically, control unit 104 may be directly connected to each antenna element or may be connected to a cable connecting between each antenna element. In this way, control unit 104 controls (independently or not) the RF radiation. Control unit 104 may comprise an RF source providing an input signal to the leaky feeder cables. In this connection, it should be understood that the leaky feeder cables enable to provide a low-cost field pesticide system resisting to any environmental conditions. The antenna array can be used in open fields as well as in closed agricultural areas. In a specific and non-limiting example, the leaky feeder cable may be a leaky coaxial cable having a length of about 100m running between the certain locations along the target field site, such as radiating coaxial cables RMC- 50H-12 of Zhuhai Hansen Technology Co. Ltd.

In some embodiments, the Radio Frequency (RF) radiation is selected to have a surface power density in the range of about 10 mWatt/m² to about 8000 mWatt/m². In order to ascertain the correct RF radiation exposure level required in order to successfully eliminate the particular infestation pest, yet without causing any collateral damage to other wildlife, or to the plant physiology itself, preliminary RF exposure calibration tests can be performed for each particular pest to be eradicated, and for each plant system to be treated, since every biological system has its own treatment threshold parameters. These tests may most conveniently be first performed in the laboratory under controlled conditions, then field experimentation can be used to provide the necessary field data. The RF radiation may be either delivered in a Continuous Wave (CW) form or in a pulsed manner. In some embodiments, control unit 104 generates a certain time pattern of the pulsed RF radiation by providing a periodic input signal shutting down the RF radiation at a certain period. The time pattern creates a pulsed field having substantially higher peak powers (i.e. maximal spike) than its average power level peak. For example, control unit 104 comprises a power timer configured to drop down the power every 2ms. Although in the figure the antenna array is placed at least partially inside a ground of the target field site, the antenna array may be placed above the ground. In this connection, it should be noted that if the antenna array 100 is placed inside the ground of the target field site to be treated, the energy generated by the antenna array 100 is selected to have a magnetic field having a surface power density having an electric field strength in the range of about 5 V/m to 50,000 V/m and an electromagnetic field having a surface power density in the range of about 10 mWatt/m² to 8000 mWatt/m². These values depend on the surface area and the size of the target field to be protected and if the field is open or placed in a greenhouse. It should be noted that the antenna array of the present invention may be used in several modes. If people are present around the target field site, the limit of 5,000 V/m is the limit permitted for humans, for a person standing about 30 cm from the source. However, if the antenna array is placed in the ground, a much higher field can be produced without any damage to person. If there is no risk that people are present around the target field site (the antenna array operates for example at night and/or if the green houses are closed) the people are working around the target field site, the surface power density is not limited to 50,000 V/m but can reach 500,000 V/m. The value of the surface power density may be varied for example by varying the length of the leaky feeder elements.

In some embodiments, control unit 104 may comprise a sensor(s) deployed around the target field site, configured and operable to detect presence of an individual and upon receiving a signal from the sensor, control unit 104 automatically switch off the input signal to the leaky feeder cables and shut down the RF radiation. The configuration of the antenna elements 102 of the antenna array is not limited to any special configuration. For example, the antenna array 100 may comprise low cost chip-based transmitters attached to each individual plant. Alternatively, the antenna array 100 may comprise a low voltage string of transmitters, which optionally may be powered by a solar panel. Alternatively, the antenna array 100 may comprise a reusable string of transmitters, attached to a supporting system of the plants.

In some embodiments, the antenna element 102 comprises coils activated such that the magnetic field outside the coil is zero, and the power of the antenna element is dependent on the number of coils.

Reference is made to Fig. IB showing a partial view of a non-limiting and specific implementation of the control unit 104 of the present invention. In this specific example the plurality of leaky feed cables 102 (e.g. 100m leaky feed cables) are directly connected to the control unit 104 for example via SMA (SubMiniature version A) connectors. However, connection between leaky feed cables 102 and the control unit may be made by wires, or may be wireless. Control unit 104 may be comprised of a processor 107 embedded therein (e.g. Linux laptop) running a computer program, or attached thereto. Alternatively, an external PC may be connected to each leaky feeder cable via individual amplifiers. The computer program product may be embodied in one or more computer readable medium(s) having computer readable program code embodied thereon. The computer readable medium may be a computer readable signal medium or a computer readable storage medium. Computer program code for carrying out operations for aspects of the present invention may be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer, or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider). These computer program instructions may be provided to the processor 107 of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks. The control unit 104 comprises a signal generator 106 (e.g. router) configured to provide a dedicated signal for each frequency and being connected on one side to the processor 107 and on the other side to the leaky feeder cables 102 via amplifiers 105 and SMA connectors. The control unit 104 is configured and operable to produce Radio Frequency (RF) energy having different patterns/modes corresponding to different types of pests to be treated (such as Whitefly, Trips, and Nematodes). Each mode comprises at least one of the following parameters, such as a certain level of energy to be emitted, a certain duration of the emission of the energy, a certain periodicity of repetition of the emission, and a certain type of modulation. The processor 107 transmits the data pattern to the leaky feeder elements 102 according to the computer program. The processor 107 may verify the power levels fed to the leaky feeder elements 102 and may also notify in case of a failure and non-functioning. The processor may be connected to a sensor module 103 comprises one or more sensors connected by wires or wireless to leaky feeder elements 102 and configured for sensing whether the leaky feeder elements 102 operate properly. Although in the present example, sensor module 103 is represented as an integrated part of control unit 104, sensor module 103 may be an external unit communicating by wires or wireless with processor 107 and/or leaky feeders elements 102. Sensor module 103 may also comprise sensor(s) for detecting presence of an individual as described above. In this case, sensor module 103 is deployed around the target field site. In a non-limiting example, the sensors may be configured for measuring electrical current and/or voltage at different locations of each leaky feeder element 102. In such example, the processor 107 is configured and operable to compare the measured currents/voltages to current/voltages required for emitting the desired RF radiation. The processor 107 may also be configured for switching off the input signal to shut down the radiation upon receiving signal of the sensor(s). In another non-limiting example, the sensors are configured for measuring radiation levels at certain locations along the field. In this case, sensor module 103 is located at certain locations along the field externally to control unit 104. In such example, the processor 107 is configured and operable to compare the measured radiation levels to the desired radiation levels along the field. The specified functions of the processor 107 can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and computer instructions. In some embodiments, the control unit 104 may comprise a plurality of amplifiers 105 configured and operable to amplify the input signal fed to the leaky feeder cables 102. In this specific and non-limiting example, each leaky feeder cable 102 has its own amplifier 105, however, this configuration is not limiting. The same amplifier may be connected to a plurality of leaky feeder cables. The signal amplifiers may be for example lOw 0.4Ghz, lOw 0.8 GHz, 5w 5.8 GHz, 20w 2.4 GHz. Each frequency requires a dedicated signal amplifier. Control unit 104 includes a power supply connected to each leaky feeder cable, and any suitable number of feeder cables may be used.

Reference is now made to Fig. 1C, which illustrates a field of tomato plants 10 arranged in ordered rows. The tomato plant with its common whitefly infestation is used as one exemplary instance of pest infestation which the technique of the present invention are intended to combat. It is to be understood, however, that this is only one example of a plant infestation against which the inventions described in the present disclosure are intended to be effective, and is not intended to limit the disclosure in any way. Since the tomato plant is a vine, with a comparatively thin stem, and can typically grow to a height of up to 1.5 m or more for common varieties, each individual tomato plant may need to be supported by its own support rod 11. It has to be noted that the tomato plant is very susceptible to whitefly infestation and virus infection during the 6 to 8 weeks after planting (before flowering and fruit setting - 50 to 70 cm height); older plants are usually able to cope with these pests. In order to provide the appropriate RF electromagnetic field at a position where it will be effective in curbing the whitefly activity on the plants, in this non-limiting example a plurality of RF transmitting antenna elements 12 are arranged vertically on an antenna support rod, at one or more positions which will ensure the maximum effect of the RF field on any whitefly infestation on the leaves of the plant. Since the radiation field source should advantageously be positioned in proximity to the center of the foliage it is intended to protect, and since the plants gradually increase their height as they grow, the antenna elements 12 may be placed at different heights on an antenna support rod 11. The transmitting antenna element 12 can either be attached to their own dedicated rods, or they can be attached to the plant support rods 11, as shown in Fig. 1C. Although depicted only schematically in Fig. 1C, an effective antenna element may be an antenna with an isotropic radiation pattern, to provide the most overall geometric coverage of the plants. The RF power can conveniently and economically be generated by a chip set including a local battery located in a transmitter unit mounted on the rod in proximity to the antenna element, so that problems of RF cable transmission are avoided. A transmitter can be provided for each antenna element, or a single transmitter unit can emit from several antenna elements located at different positions. The power supply for each transmitter unit can either be supplied by the control unit (not shown) via the feeder cable 15 laid along the rows of the field and feeding the transmitter units up the antennae rods, or each transmitting unit can be made self-contained, and operate independent of any external power supply by use of a solar power collector and converter. Such a solar power source may also be located remotely from the transmission units themselves, such as periodically along or at the ends of a row of plants, and the electric power generated is fed to each transmitter unit by a local cable.

As an alternative to having a plurality of low power transmitters dispersed in or on essentially every plant in the most effective positions, it is also possible to use a smaller number of higher powered transmitters disposed so that the RF radiation therefrom covers a group of plants, rather than a single plant. In this configuration, care must be taken that the maximum RF field density at the points on the plants closest to the transmitters does not have any negative effects on those parts of the plant, and that the level of RF does not cause any other collateral environmental damage, such as to bees. Such a configuration will reduce costs of the system since the number of transmitters is reduced, and the infrastructure for installing them is also reduced accordingly.

Once the configuration to be used is determined, the system is designed as an RF electromagnetic shield system, effective for the field scale to be used, and including the number of transmitter units and the effective distance between them, the distance from the ground, or the height within the plants, and any other parameters necessary in order to ensure effective application of the RF power at the position where it is most effective.

Reference is now made to Fig. ID, which illustrates an antenna array 400 comprising a plurality of antenna elements 402 generating a Radio Frequency (RF) radiation and a control unit 104. In this embodiment, the antenna elements 402 comprise leaky feeder elements configured and operable to emit RF radiation in a controllable manner. The leaky feeder elements provide RF radiation in an almost uniform manner and enable to ensure controllable RF radiation having a certain minimum and maximum throughout the target field, in any environmental conditions.

For pests' elimination, the control unit 104 may select the power level at the leaky feeder elements to be about 20W which corresponds to about 43 dBm enabling to produce a surface power density up to 30,000 mW/m² if there is no risk that people are present around the target field site. The leaky feeder element may be partially covered in the ground, in order to protect the plants from pest like Thrips at the Pupa stage.

As illustrated, the leaky feeder elements 402 may be configured and operable to support plants extending along the target field site. However, the leaky feeder elements 5 402 may also be placed at the proximity of the plants and a supporting rod may be used to support the plants. For example, the leaky feeder elements 402 may be placed in contact with the plants or at a distance of up to 0.5 m from the plant.

In some embodiments, the plurality of antenna elements comprises four antenna elements, each element being arranged in the array to emit radiation in a different0 direction such that the target field site is exposed to the radiation.

Reference is now made to Fig. 2, which shows schematically a non-limiting example of a partial view of a field pesticide system 200 according to one embodiment of the present invention in which the RF power can be generated and distributed to the transmission antenna element in the vicinity of the plant foliage which it is intended to5 protect. Fig. 2 schematically presents a field pesticide array 200 according to some embodiments of the present invention comprising an antenna element 24 being a part of an antenna array and being connected to a control unit comprising an RF generator 20 configured to feed an input signal to the antenna element 24. The connection between the antenna array and the RF generator may be wired or wireless.

0 In this specific and non-limiting example, the RF generator 20 is mounted on a support rod 22 disposed close to the stem 23 of a plant. It should be noted that the position of the RF generator 20 is not limited to any place and can be placed anywhere in the proximity of the antenna array. The support rod 22 may be a telescopic support rod to move periodically with growth of the plant the position of the RF generator 20 and/or of5 the antenna element 24. In this example, the antenna element 24 is disposed in the central region of the plant foliage 25, such that its effect is maximized. Alternatively, more than one transmission antenna element can be mounted on the support rod, each at a different height, to provide coverage of the foliage for large plants or for various stages of growth of the plant. If the infestation period occurs only at a well-defined time period relative to0 the plant's growth, then such an adjustable height mechanism or multiple antenna use may be unnecessary. The power supply to the RF generator 20 can be provided remotely by a power feed cable 26. Fig. 3A illustrates another possible non-limiting configuration of an alternative implementation of the field pesticide array 300A, in which the RF power can be generated at a remote control unit 30, and fed to individual transmission antenna elements 31 on the plants, for example by coaxial RF feed cables 32. Balancing networks may be required in 5 the cables to ensure equitable distribution of the RF power. In some embodiments, the control unit 30 is configured and operable to produce Radio Frequency (RF) energy having different modes corresponding to different types of pests to be treated (such as Whitefly, Trips, Nematodes) Each mode comprises at least one of the following parameters such as a certain level of energy to be emitted, a certain duration of the

10 emission of the energy, a certain periodicity of repetition of the emission, and a certain type of modulation. The technique of the present invention treats different types of pest including pests at all stages of metamorphosis, their eggs, and viruses. The inventors of the present invention have performed experiments for different pests and for different host plants, in order to estimate the correct RF dosage to use for each pest, and to avoid

15 environmental damage to the host flora and visiting fauna.

In some embodiments, the field pesticide system of the present invention is able to eliminate plant parasitic nematodes by placing the antenna array within the ground and generating a strong magnetic field.

Fig. 3B illustrates, by the way of a picture, another possible non-limiting

20 configuration of an alternative implementation of the field pesticide array 300B, in which the RF power can be controlled at a remote control unit 30, and fed to one or more leaky feeder cables 34 extending substantially parallel to the surface of the soil to the plants. Optionally, a plurality of leaky feeder cables 34 is used, and the leak feeder cables 34 are disposed at different distances from the surface of the soil. Each of the leaky feeder cables

25 34 is connected to the control unit 30.

Fig. 4 is a schematic illustration of yet another alternative implementation of the system of the present invention, in which a self-propelled traveling boom 40 system is used, similar to the type of traveling boom used to irrigate or to provide pesticide spray to large fields. However, instead of a fluid dispensing system, the booms are equipped

30 with RF transmitter antenna elements 41 suspended from the boom at intervals equivalent to the spacing between rows of plants. In use, the boom is positioned such that the RF transmitter antenna elements 41 are located immediately above or even within the foliage of a lateral row of the plants to be treated, and the transmission is operated for the time required to eliminate the infestation on the lateral row of plants. A directional antenna directing the RF transmission downwards towards the plant can be used to increase the effectiveness of the transmitter. As described in the previous implementations, the RF control unit can be disposed either in proximity to the RF transmitter antenna elements, or the RF control unit may comprise one or more RF generating units 43 which can be disposed at positions along the length of the boom or at its end, and the RF power is fed to the antenna elements by RF cables. When treatment time is completed, the boom can be moved longitudinally to the next lateral row of plants, and the procedure is repeated. In this way, it becomes possible to cover a very large field with a limited number of RF transmission units, such that the capital cost of the installation becomes reasonable, even for very large cultivated areas.

EXPERIMENTAL DATA

A series of experiments was performed to demonstrate that the inventors have developed a technique which enables to restrain pests, and thereby the damages they cause to important agricultural crops.

The first experiment showed that RF was able to affect whiteflies. Whiteflies were reared with tomato plants in insect-proof wooden cages (75 L x 45 W x 45 H cm) (6 test plants at the 5-7 leaf stage, about 20 insects per plant) in the presence of two RF sources. Commercially available Wi-Fi routers operating at 2.4 GHz were used for these experiments. Controls were conducted in similar cages with no RF sources. A single Tomato yellow leaf curl virus (TYLCV)-infected tomato plant was introduced in each cage. In the cages with the RF sources, all the test plants remained symptomless, while in the control cages, all the plants were diseased. Hence, in this experimental setting, the RF waves protected the tomato plants from whitefly-mediated inoculation of TYLCV.

The second experiment showed that RF was able to eradicate whiteflies. Six groups of six tomato plants at the 5-7 leaf stage were reared in an insect-proof air- conditioned room. Three groups of six plants were set around two RF sources. Controls consisted of three groups of six tomato plants of the same age, without the presence of the RF source. Whiteflies were released on the plants (about 30 insects per plant). The whiteflies were observed every 30 min during the first two hours, then once a day over two days. After 1 hour in the presence of the RF sources, the whiteflies ceased to move. The next day, all the insects were dead. In the control plants, most whiteflies remained alive for the duration of the experiment.

The third experiment appraised the effect of RF on pollinating bees. Since, in the greenhouse, tomato fruit setting depends on pollination, commercially-purchased bumble bees are usually used as pollinators. Therefore, it was of interest to find out whether the RF fields used for these experiments, and which had been shown to be effective against whiteflies, would impair bee performance, although the flowering stage is rather late, at a time when plants are less susceptible to viruses vectored by whiteflies. Two approaches were taken: 1) Effect of radiation on bee survival, and 2) effect of radiation on bee feeding. In the first approach, bees were confined to Petri dishes (six bees per dish) with access to water and honey. Five dishes were subjected to the RF transmitters and five were used as controls. Mortality was continuous throughout, with the last bee dying on day 29. There was no difference in mortality between the two groups. In the second approach, bees were released in a flight chamber containing sweet water and pollen sources. RF sources were disseminated in the chamber, and bees were monitored for periods of 20 min. Bee activity was not affected by the RF antennas. The effect of radiation was similar for nectar and for pollen foraging. Relatively low levels of radiation (one antenna element) did not hinder bees from approaching the feeders, or the time they spent imbibing the sucrose solution. However, higher levels of radiation (three antenna elements) reduced the bees' visitation rates and the time that they spent imbibing sucrose solution at the feeder.

The fourth experiment showed that RF had no significant effect on tomato flowering and fruit setting. These effects were tested in a net house subjected to day and night external ambient temperatures. Eight groups of six tomato plants at the 5-7 leaf stage were reared in pots. Four groups of six plants were set around an RF source. Controls consisted of four groups of six tomato plants of the same age without the RF source. The plants were watered every two days and the date of flowering was noted. The results indicated that the RF source did not influence tomato development, flowering and fruit setting, which were identical to that of tomato plants not subjected to the RF treatment.

The fifth experiment was aimed at optimizing the RF effect on whiteflies. The RF treatment conditions were optimized for another crop, this being cucumbers. Leaves of this plant are bigger than those of the tomato. Whiteflies feed better on cucumber leaves than on tomato leaves, and do not move from the leaves, unless positively forced to. The experiments were designed to measure whitefly survival as a function of RF transmitter radiation output. In the experimental procedure, a detached cucumber leaf with the whiteflies feeding on it was subjected to continuous RF radiation. RF radiation was applied from a pulsed source operating at 2.4 GHz, the Wi-Fi router transmitters mentioned above, one, two or three router antennas being disposed in close proximity and the surface power density ranged from 1.1 to 18.5 mW/m², depending on the number of sources used. One antenna provided approximately a surface power density in the range of about 1 to 4 mW/m², two antennae provided approximately a surface power density in the range of about 4.5 to 6 mW/m² and three antennae provided approximately a surface power density in the range of about 11 to 18.5 mW/m².

The ability or not of the whiteflies to fly off from leaves subjected to RF radiation was monitored every 3 minutes, up to 12 minutes, and compared. The control experiment without any applied radiation showed that all the whiteflies on the control leaf were able to fly away after 12 minutes of observation. In the experiments performed on the leaves, the percentage of non-flying insects as a function of exposure time and the intensity of irradiation, was calculated. The results showed that the damage to whitefly flight capacity increased with the intensity of the radiation and with time of exposure. A level of 25 mW/m² applied for 12 minutes appeared to be totally adequate for neutralization of most whiteflies on cucumber leaves, using the type of RF radiation source used in these experiments. Such radiation levels for the duration of the experiments, did not show any damage to the leaves. The above power levels were measured in experiments aimed at adult whiteflies. Since the surface power density levels and exposure times required for destruction of the eggs of the whitefly may be different from those required for destruction of the whiteflies, it is to be understood that if it is known at what stage of development of the plant the whiteflies have already laid their eggs, it will be possible to execute the eradication process at the characteristic energy level required for destroying the eggs, even at a time after the whiteflies have already left the plant.

The sixth experiment tested the ability of the leaky feeder RF system of the present invention to control whiteflies and to prevent transmission of Tomato yellow leaf curl virus (TYLCV), one of the major viruses affecting tomato growers worldwide. In the three consecutive experiments, about 25-30 tomato plantlets at their 6-8 true leaf stage were placed within a i m diameter circle consisting of a RF cable, rolled/coiled several times on itself. The RF was measured all along the cable. TYLCV-containing whiteflies were released on the plants, 5-10 whiteflies per plant. The results showed that RF had a strong and durable negative impact on settlement of whiteflies, which disappeared from the tomato plants within a few hours, and on the reproduction capacity of the insect as reflected by their inability to lay eggs. The RF setting overwhelmingly prevented whiteflies to transmit TYLCV to plants (only one infected plant out of 43 as tested by PCR). These experiments allowed to fine-tune the RF intensities needed to eradicate whiteflies.

For each plant type, the inventors have found how to establish the effective intensity of the radiation. If a frequency is used which coincides with one of the frequency bands used for mobile telecommunications use, it is important that the emission level chosen be sufficiently low that its use be allowed by the broadcasting regulating authorities. Since radiation power densities of the order of 25mW/m² are believed to be encountered in cities only in areas close to transmitter sites or radar systems, and since the described systems are intended for use only in rural areas, it is believed that regulatory limitations will not hinder the widespread use of these systems.

In a seventh set of experiments, the system of the present invention was tested in the net houses of Southern R&D, Israel. The 6 x 6 m net houses had a metal frame and were covered on all sides with 50-mesh nets to prevent entry of insects. The conditions used in commercial settings by farmers and growers were followed as close as possible, namely a commercial tomato variety tolerant to TYLCV was planted, and, when indicated, pesticides were sprayed. The net houses were monitored by thoroughly examining tomato leaves for the presence of whiteflies {Bemisia tabaci), the vector of TYLCV, but also for the presence of other insects impairing tomato cultures such as thrips (Frankliniella occidentalis), the vector of Tomato spotted wilt virus (TSWV), and red spider mites {Tetranycus spp.), which produce white webs suffocating and killing the plant. The intensity of the RF was monitored all along the setting, in the close vicinity of the growing tomatoes.

In an eighth set of experiments, Whiteflies {Bemisia tabaci biotype B) were raised on tomato plants (cultivar Daniella). RF was applied when the plants were at their 6-8 leaf stage and each leaf contained large numbers of whiteflies at different stages of development, including eggs, larval stages (crawlers, instars and pupae) and flying adults, males and females. The source of RF was located close to the leaves, and the insects were subjected to radiations for two hours. It was shown that RF destroys the structure of the whitefly egg laid on tomato leaves. The insects were subjected to radiation for four days. It was shown that RF dries up instars and pupae. The larvae in the pupae has died. RF radiation destroyed the shape of the egg, killed pupae and generated hollow spaces in the adult. The internal organs of the pupa were totally misshaped and the borders of the pupae were dry. It was also shown that RF causes a marked disorganization of the whitefly internal organs. It seems that the haemolymph shrunk, and, as a result, the internal organs such as guts and reproductive system were strongly compressed. RF radiation increased the temperature of the internal fluids of the insects, especially the haemolymph - the insect primitive open blood system - in which the vital organs exist. As a result, primordial functions such as flight, feeding and reproduction, are impaired. RF radiation thus had a lethal effect on whitefly eggs, desiccated instars and pupae, and induced internal damages to whiteflies, causing their death. The insecticidal properties of RF radiation which were seen in the tomato net house were the direct result of the RF effects on the insects. When whiteflies encounter the RF insecticide system, the radiations penetrate the body of the insect and dehydrate and jellify the haemolymph, which is the open blood system of the insect. This is achieved, most likely, by heat-inducing vibrations. Since the insect external volume remains approximately constant due to the rigid cuticle and wax, jellification reduces the internal volume of the fly, creating empty volumes and a vacuum. As a result, the soft organs such as guts and ovaries, are compressed, and shrink. Therefore, feeding and egg development are impaired, and the insects die. Eggs that the insect may lay until it is seriously affected by the RF radiation, and which do not have a strong protective envelope, collapse and implode. As a result, the eggs will not develop, and the emergence of a new generation of whiteflies is prevented.

Reference is made to Fig. 5A showing schematically a map of an example of an antenna array 500 of the present invention implemented as a RF greenhouse with plants, according to some embodiments of the present invention. In this specific and non-limiting example, the antenna array 500 was in place at the time of planting the seedlings. Antenna array 500 comprises in this specific and non-limiting example one RF cable 502 (i.e. leaky feeder cables) and a control unit 504 implemented by an RF source connected to the RF cable 502 for providing an input signal to the leaky feeder cables and for controlling the RF radiation. In this specific and non-limiting example, the RF cable 502 passes through the drip irrigation hose tubes on which each plant is supported. Tomatoes were planted in three flowerbeds (two rows in each) distant from each other by 180 cm. Each flowerbed was watered by two rows of drip-irrigation hose tubes. Along each row, seedlings were planted in duplicates, at a distance of 40 cm from each other.

Reference is made to Fig. 5B showing the number of insects 2, 3 and 4 weeks after the beginning of the experiment.

The effect of RF on insects present on tomato plants was appraised (presence, multiplication, fertility) using three different sets of conditions in three different greenhouses (6 x 6 m):

1) The plants were continuously and solely subjected to RF radiations by using the system of the present invention. The results are represented by the intervals " 1 " of the different histograms indicative of different dates.

2) The greenhouse was not treated, neither by chemicals nor by RF, and the plants were left to grow without interference. The results are represented by the intervals "2" of the histograms.

3) The plants were treated with pesticides, mimicking the protocol farmers usually use to combat insect pests, especially whiteflies, in a commercial setting. The results are represented by the intervals "3" of the histograms.

Tomato plantlets from the TYLCV-tolerant cultivar Tori (Zeraim Gedera) about three weeks after sowing in a nursery, were used without any prior insecticidal treatment. The system of the present invention was in place at the time of planting the seedlings. Ninety seedlings were used per net house. Tomatoes were planted at a distance of 40 cm in three flowerbeds distant from each other by 180 cm. Each flowerbed was drip-irrigated. The presence of whiteflies and their eggs, thrips and red mites was monitored twice a week in the growing tomato plants.

Plantlets were planted in the net houses on September 29, 2016. The next day, the three net houses were inoculated with whiteflies and with thrips by dispensing amongst the tomato plantlets about 15 leaves with at least two whiteflies and five pepper flowers with about two thrips each. The same day, the pesticide-treated net house was sprayed with chemicals, and sprayed again two weeks later. Two weeks after the start of the experiment, the untreated net house was infested with insects. Pesticide treatment reduced the insect population. RF exerted effective control. One week later, the effect of the pesticide was felt. A week later, the number of insects returned to previous values in the pesticide treated net house. All along the experiment, the system of the present invention maintained the insect populations to a minimum, more effectively than pesticide sprays.

The experiments showed that the technique of the present invention provided significant protection from insects: the number of insects in the net house treated by using the system of the present invention was close to nil compared to the other two net houses, pesticide-treated and non-treated, where there were significant numbers of whiteflies and thrips which colonized the tomato plants and of red mites forming dense white webs on the leaves. Whitefly eggs were not found on tomato leaves grown in the net house treated by using the system of the present invention. Altogether, the beneficial effect of the system of the present invention in protecting tomato plants from deleterious insects, was more efficient than the spraying of pesticides.

Moreover, it should be noted that, the productivity of the crop is increased by using the antenna array of the present invention. In normal uses of pesticides, the plants are not protected 24 hours a day and therefore at a certain stage, the effect of the pesticides diminishes. The plant activated biological mechanism should then protect itself from the insects, taking from the plants energy that otherwise would be used for growth. Experiments conducted on basil plants, using the antenna array of the present invention, show the plant provided greater amount of basil than expected. It is appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the present invention includes both combinations and sub combinations of various features described hereinabove as well as variations and modifications thereto which would occur to a person of skill in the art upon reading the above description and which are not in the prior art.

Claims

CLAIMS:

1. An antenna array comprising a plurality of antenna elements generating Radio Frequency (RF) radiation and a control unit being connected to said plurality of antenna elements and being configured and operable for controlling said RF radiation; wherein said plurality of antenna elements comprise leaky feeder elements, is configured and operable to emit said RF radiation, said antenna array being configured and operable for extending along a target field site to be treated for pesticide infestation at certain locations.

2. The array of claim 1, wherein said leaky feeder elements are configured and operable to support plants extending along said target field site.

3. The array of claim 1 or claim 2, wherein said plurality of antenna elements comprise four antenna elements, each element being arranged to emit radiation in a different direction such that said target field site is exposed to said radiation.

4. The array of any one of claims 1 to 3, wherein said control unit is configured for generating Radio Frequency (RF) radiation having a surface power density in the range of about 10 mWatt/m² to about 8000 mWatt/m².

5. The antenna array of claim 4, wherein said surface power density is in the range of about 20 mW/m² to 1000 mW/m².

6. The array of any one of claims 1 to 5, wherein said plurality of antenna elements are placed inside the ground of a target field site to be treated.

7. The array of any one of claims 1 to 6, wherein said plurality of antenna elements is placed above the ground of the target field site or at least partially inside the ground of the target field site.

8. The array of any one of claims 1 to 7, wherein said control unit is configured and operable to control different modes corresponding to different types of pests to be treated and to generate a different time pattern accordingly; each mode comprises at least one of the following parameters: a certain level of energy to be emitted, a certain duration of the emission of said energy, a certain periodicity of repetition of the emission, and a certain type of modulation.

9. The array of any one of claims 1 to 8, wherein said control unit is configured and operable to generate at least one of a magnetic field having a surface power density having an electric field strength in the range of about 5 V/m to 50,000 V/m and an electromagnetic field having a surface power density in the range of about 10 mWatt/m² to 8000 mWatt/m².

10. The array of any one of claims 1 to 9, wherein said control unit controls said RF energy to be in a Continuous Wave (CW) form or pulsed.

11. The array of any one of claims 1 to 10, wherein said control unit comprises an amplifier connected to each leaky feeder element and configured and operable to amplify an intensity signal outputted to the leaky feeder element.

12. The antenna array of any one of claims 1 to claim 11, wherein said antenna array is solar powered.

13. A field pesticide system comprising:

a control unit being configured and operable to produce Radio Frequency (RF) energy having different modes corresponding to different types of pests to be treated; each mode comprises at least one of the following parameters: a certain level of energy to be emitted, a certain duration of the emission of said energy, a certain periodicity of repetition of the emission, and a certain type of modulation; and an antenna array connected to said control unit wherein said antenna array comprises a plurality of antenna elements generating Radio Frequency (RF) radiation and a control unit being connected to said plurality of antenna elements and being configured and operable for controlling said RF radiation; wherein said plurality of antenna elements comprises leaky feeder elements is configured and operable to emit said RF radiation, said antenna array being configured and operable for extending along a target field site to be treated for pesticide infestation at certain locations.

14. The field pesticide system of claim 13, wherein said different types of pests comprises pests at all stages of metamorphosis, their eggs, and viruses they carry.

15. The field pesticide system of claim 13 or claim 14, wherein said antenna array is placed inside the ground of a target field site to be treated and said control unit is configured and operable to produce Radio Frequency (RF) energy generating at least one of a magnetic field having a surface power density having an electric field strength in the range of about 5 V/m to 50,000 V/m and an electromagnetic field having a surface power density in the range of about 10 mWatt/m² to 8000 mWatt/m².

16. The field pesticide system of any one of claims 13 to claim 15, wherein said leaky feeder elements are configured and operable to support plants extending along said target field site.

17. The field pesticide system of any one of claims 13 to claim 16, wherein said plurality of antenna elements comprise four antenna elements, each element being arranged to emit radiation in a different direction such that said target field site is exposed to said radiation.

18. The field pesticide system of any one of claims 13 to claim 17, wherein said control unit is configured for generating Radio Frequency (RF) radiation having a surface power density in the range of about 10 mWatt/m² to about 8000 mWatt/m².

19. The field pesticide system of any one of claims 13 to 18, wherein said plurality of antenna elements is placed above the ground of the target field site or at least partially inside the ground of the target field site.

20. The field pesticide system of any one of claims 13 to 19, wherein said control unit controls said RF energy to be in a Continuous Wave (CW) form or pulsed.

21. The field pesticide system of any one of claims 13 to 20, wherein said control unit comprises an amplifier connected to each leaky feeder element and configured and operable to amplify an intensity signal outputted to the leaky feeder element.

22. The field pesticide system of any one of claims 13 to 21, wherein said antenna array is solar powered.

23. A method for eliminating pests comprising generating Radio Frequency (RF) radiation having a surface power density in the range of about 10 mWatt/m² to about

8000 mWatt/m² along a target field site to be treated for pesticide infestation at certain locations.

24. The method of claim 23, wherein said generating of the Radio Frequency (RF) radiation comprises placing an antenna array above the ground of the target field site or at least partially inside the ground of the target field site.

25. The method of claim 24, wherein said placing of an antenna array comprises arranging leaky feeder elements above the ground of the target field site or at least partially inside the ground of the target field site.

26. The method of claim 23 to claim 25, wherein said generating of the Radio Frequency (RF) radiation comprises producing Radio Frequency (RF) energy at different modes corresponding to different types of pests to be treated; each mode having a plurality of parameters comprising at least one of a certain level of energy to be emitted, a certain duration of the emission of said energy, a certain periodicity of repetition of the emission, and a certain type of modulation.