SE543621C2 - Device for germ-free and microbiome controlled growth of plants - Google Patents

Abstract

A device (1) for growing plants (18) under controlled microbe conditions comprising an upper compartment module (2) having a first cavity (8) and being adapted for housing above-ground parts of a plant (18), a lower compartment module (3) having a second cavity (12) and being adapted for housing below-ground parts of a plant (18), and a middle barrier module (4) arranged between the upper and lower compartment modules and adapted to house a seedling or a seed for germination within an internal third cavity (13). The middle barrier module (4) comprises a filling material (17) in which a seed or seedling may be positioned and fixed and which allows growth of said seed or seedling, said filling material (17) substantially isolating the first cavity (8) of the upper compartment module (2) from the second cavity (12) of the lower compartment module (3), such that the first cavity (8) and the second cavity (12) are not in any fluid communication with each other.

Description

1DEVICE FOR GERl\/I-FREE AND l\/llCROBlOl\/IE CONTROLLED GROWTH OF PLANTS TECHNICAL FIELD The present disclosure relates to the field of plant growth and the ability to grow plants under germ-free conditions and controlling the internal microbiome of said plants.

BACKGROUND ART I\/licroorganisms associated with plants, also known as the plant microbiome, have afundamental role on plants growth, health, and tolerance to biotic and abiotic stresses.However, the discovery of new microorganisms and studying their role is a major challengedue to the presence of an abundant and phylogenetically rich community of microorganisms,including prokaryotes and eukaryotes, living in and on the same host. ln addition, it is a majorchallenge to separate microorganisms that naturally occur as part of the plant microbiomefrom those that come from the external environment e.g. soil, air, etc. I\/|oreover, there ismounting evidence that plant-associated-microbes are site specific, i.e. root, leaves, flower, or fruit have their own specific microbial communities that differentiate them from each other.

SUMMARY OF THE INVENTION There is a need to work with plants without microorganisms, under germ-free conditions, andto maintain the plants in germ-free conditions. Furthermore, there is a need for tools thatallows studying ofthe location of site-specific microbes on or within a plant, and the consequences or effects of such site-specific presence on or within a plant.

The objective of the present invention is to provide a device that allows for germ-freeculturing and growth of plants. Furthermore, it is an objective to provide a device thatadditionally allows for the study of site-specific microbes by separating the plant aerial parts system and the root system, thus avoiding cross contamination between the two systems. 2The objectives above are attained by a device that will isolate above-ground parts of a plantfrom the below-ground parts of the same plant, while keeping the entire plant isolated from an external environment as desired.

According to a first aspect there is provided a device for growing plants under controlledmicrobe conditions comprising an upper compartment module, adapted for housing above-ground parts of a plant, comprising a first top wall, at least one side wall, and a first bottomwall, the first top wall arranged opposite to the first bottom wall, separated in a longitudinaldirection by the sidewall, such that a first cavity is formed within the upper compartmentmodule; a lower compartment module, adapted for housing below-ground parts of a plant,comprising a second top wall, at least one side wall, and a second bottom wall, the second topwall arranged opposite to the second bottom wall, separated in a longitudinal direction by thesidewall, such that a second cavity is formed within the lower compartment module; and amiddle barrier module adapted to house a seedling or a seed for germination within aninternal third cavity thereof formed by at least one sidewall, the middle barrier module havinga top opening and a bottom opening and being extended in a central longitudinal axialdirection ofthe device, the middle barrier module being arranged between the uppercompartment module and the lower compartment module along a longitudinal central axis ofthe device, being connected by the top opening to an aperture in the first bottom wall ofthe upper compartment module and by the bottom opening to an aperture in the second top wall of the lower compartment module, characterised in that the middle barrier module is-aáa-pte-eå- tacompriseg a filling material in which a seed or seedling may be positioned and fixed andwhich allows growth of the seed or seedling, the filling material substantially isolating the firstcavity of the upper compartment module from the second cavity of the lower compartmentmodule, such that the first cavity and the second cavity are not in any fluid communication with each other.

According to some embodiments, the internal third cavity of the middle barrier module iscone shaped or funnel shaped, such that the top opening of said cavity is wider than the bottom opening of said cavity.

According to some embodiments, the upper compartment module and/or the lower compartment module comprises at least one aperture on a sidewall. 3According to some embodiments, the at least one aperture may be fitted with any of one or more filter, a removable plug, an injection port, or a connector to connect the device to a pUmp.

According to some embodiments, the upper compartment module, the lower compartmentmodule and the middle barrier module are manufactured of an autoclavable, transparent, polymeric material, such as polypropylene or polycarbonate.

According to some embodiments, the middle barrier module is detachably attached to the upper compartment module and to the lower compartment module.

Aceord-Eng-to--some--emiso-dä-nfeert-ts,--the-midelle-ba-r-rier--Fri-efei-u-le-fuFth»ar-ce>a=n§§rise§-a-=šilläng-- -m-a-teråa-š--to-fâxate--the--seeá--or--sae-al-Eing-theerein,--a-ef:ei-to--p:fovida-a--ba:friar-betæveen-the-šš-rst- According to some embodiments, said filling material is chosen from a group comprisingsterile agarose, petroleum gel, wax, paraffin or grease, preferably agarose, and optionally also a sterile tissue material is comprised in the middle barrier module.

According to a second aspect there is provided a method of planting and growing germ-freeplants using the device according to any of the embodiments of the first aspect, comprisingperforming, in a germ free environment, the steps of: A) placing a seed or a seedling in :utifilling material within the third cavity ofthe middle barrier module, wherein tlïa seed ispositioned on a sterile tissue adjacent to the bottom opening of the middle barrier moduleadapted to be connected to the lower compartment module, where after the filling material isadded to the third cavity ofthe middle barrier module to encapsulate the seed within themiddle barrier module, or a~_t__r_a_«g__seedling is positioned within the middle barrier module, withthe part of the seedling intended to grow above ground towards the top opening of themiddle barrier module, and the part of the seedling intended to grow below ground towardsthe bottom opening of the middle barrier module, where after the filling material is added tothe third cavity to fixate the seedling at a crown area of the seedling within the middle barriermodule; B) adding water, soil or a liquid nutrition solution into the second cavity of the lower compartment module, C) attaching the top opening of the middle barrier module to the first 4bottom wall ofthe upper compartment module, and the bottom opening ofthe middle barriermodule to the second top wall of the lower compartment module, D) allowing the seed or seedling to grow.

According to a third aspect there is provided a kit of parts comprising the device according to any of the embodiments of the first aspect, avherešar: the filling material of the device may be chosen from a group comprising sterile agarose, petroleum gel, ..\ in wax, paraffin or grease, preferably agarose, and wšierešrs 'the kit of arts optionally comprises a sterile tissue material.

Effects and features of the second and third aspects are to a large extent analogous to thosedescribed herein in connection with the first aspect. Embodiments mentioned in relation to the first aspect are largely compatible with the second and third aspects.

The present invention will become apparent from the detailed description given below. Thedetailed description and specific example disclose a preferred embodiment ofthe invention byway of illustration only. Those skilled in the art understand from guidance in the detailed description that changes and modifications may be made within the scope of the invention.

Hence, it is to be understood that the herein disclosed invention is not limited to the particularcomponent parts of the device described or steps of the methods described since such deviceand method may vary. lt is also to be understood that the terminology used herein is forpurpose of describing particular embodiments only, and is not intended to be limiting. ltshould be noted that, as used in the specification and the appended claim, the articles "a","an", "the", and "said" are intended to mean that there are one or more ofthe elementsunless the context explicitly dictates otherwise. Furthermore, the words "comprising", "including", "containing" and similar wordings does not exclude other elements or steps.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1. An embodiment of the device according to the present disclosure Figure 2. Illustration of the parts comprised in the embodiment of Fig. 1 Figure 3. Schematic drawing ofthe embodiment of Fig 1 with a plant positioned therein.

Figure 4. A cross-sectional view of the arrangement of Fig. 3.

DETAILED DESCRIPTION A plant may be defined as comprising above-ground parts and below-ground parts. The above-ground parts of a plant comprises stem, leaf stalks, leaves, shoots, flower buds, flowers andfruits. The below-ground parts of a plant comprises the root system comprising main andsecondary roots and root hairs. The area where the root system joins the stem of a plant iscalled the crown. There is increasing evidence that plant-associated-microbes are site specific,i.e. root, leaves, flower, or fruit have their own specific microbial communities that differentiate them from each other within one plant.

The device disclosed herein allows for separation of above-ground parts of a plant frombelow-ground parts of a plant, and thus the ability to avoid cross-contamination between theplant's above- and below-ground parts. The separation is achieved by placing a barriersurrounding and embedding the crown. The barrier preferably comprises a material thatfixates the plant while being flexible enough to allow the plant to grow and expand, and without breaking or suffocating the plant, or breaking the barrier material.

The device for growing plants under controlled microbe conditions, as disclosed herein,comprises an upper compartment module, a lower compartment module, and a middle barriermodule arranged between the upper compartment module and the lower compartment module.

The upper compartment module is adapted for housing the above-ground parts of a plant andcomprises a first top wall, at least one side wall, and a first bottom wall, said first top wallarranged opposite to said first bottom wall, separated in a longitudinal direction A-A by saidsidewall(s), such that a first cavity is formed within the upper compartment module. The uppercompartment module may comprise three or more sidewalls. According to one embodiment,the upper compartment module comprises four sidewalls. lt is also possible that the upper compartment module comprises one sidewall that is circular in cross-section.

The lower compartment module is adapted for housing the below-ground parts of a plant and comprises a second top wall, at least one side wall, and a second bottom wall, said second top 6wall arranged opposite to said second bottom wall, separated in a longitudinal direction A-A bysaid sidewa||(s), such that a second cavity is formed within the lower compartment module. Thelower compartment module may comprise three or more sidewalls. According to oneembodiment, the lower compartment module comprises four sidewalls. lt is also possible thatthe lower compartment module comprises one sidewall that is circular in cross-section. Thelower compartment module is designed so that it may be safely positioned on a flat surface, byhaving a flat exterior surface of the second bottom wall, or by being provided with feet or other means for support, in order for the device to be able to be free-standing.

The middle barrier module is adapted to house a seedling or a seed for germination within aninternal third cavity thereof formed by at least one sidewall, and said middle barrier module hasa top opening and a bottom opening and is extended in a central longitudinal axial direction A-A of the device. The middle barrier module preferably has one sidewall that is circular in cross- section. However, also embodiments comprising three or more sidewalls are possible.

The middle barrier module is arranged between the upper compartment module and the lowercompartment module along a longitudinal central axis A-A of the device, being connected bythe top opening to an aperture in the first bottom wall of the upper compartment module andby the bottom opening to an aperture in the second top wall of the lower compartment module.Thereby an upper part of the middle barrier module is connected to the upper compartmentmodule, and a lower part ofthe middle barrier module is connected to the lower compartmentmodule. Preferably, the middle barrier module is detachably attached to the uppercompartment module and to the lower compartment module, in order to facilitate the positioning of a plant, seed or seedling in the device.

As disclosed above, the middle barrier module may have one, two, three or more sidewalls.What is important is that the shape of the middle barrier module, and in particular the shape ofthe top opening and the bottom opening, fits snuggly into the aperture in the first bottom wallof the upper compartment module and into the aperture in the second top wall of the lowercompartment module, respectively, so that the device is sealed at the connection sites between the modules.

The middle barrier module comprise§ a filling material in which a seed or seedling may be positioned and fixed and which allows growth of said seed or seedling. The presence of 7a filling material in the middle barrier module substantially isolates the first cavity of the uppercompartment module from the second cavity of the lower compartment module, such that the first cavity and the second cavity are substantially not in fluid communication with each other.

The internal third cavity of the middle barrier module is preferably cone shaped or funnelshaped, such that the top opening of said tube is wider than the bottom opening of said thirdcavity, said third cavity adapted to comprise said filling material. This shape of the internalthird cavity facilitates the positioning of the seed or seedling, as the risk of the seed or seedling falling down into the lower compartment module is decreased.

The upper compartment module and/or the lower compartment may comprise at least oneaperture on a sidewall. An aperture on any of the modules may be fitted with any of one ormore filter(s), a removable plug, an injection port, or a connector to connect the device to a pUmp.

An aperture in the upper compartment module may preferably be fitted with S 0.22 um filters,allowing for plant respiration. The filters may be of either hydrophobic or hydrophilic materialsuch as Nylon or mixed cellulose esters (MCE). The number of filters per device can vary fromone to multiple depending on the plant's needs and/or the purpose of usage. The uppercompartment may also comprise apertures for plant manipulation e.g. sampling, inoculation,measurement etc. Furthermore, a pump can be connected through a tube to an aperture in the upper compartment module for air sampling or ventilation.

An aperture in the lower compartment module may also be fitted with a filter or may be forprovision of water or nutrition solutions, or for sampling, measurement etc. The lowercompartment module may preferably comprise two apertures, one on an upper part of asidewall for inoculation, sampling and measurements, and one on a lower part of a sidewallfor drainage, in case a liquid substrate is used instead of soil or in case of excess water in thesoil. An additional filter can be added to an aperture on the lower compartment module forsoil respiration, such as a S 0.22 um filter, as specified for the upper compartment module.Furthermore, a pump can be connected through a tube to an aperture in the lowercompartment module for gas/liquid injection e.g. oxygen for root respiration. lt may be preferable to use a liquid substrate, such as a nutrition solution, as soil is considered a major 8source of microorganisms, and thereby may not lead to a germ-free environment for the plant in the device.

The apertures in the upper and lower compartment modules thus enables sampling andmanipulation ofthe plant without the need to open up the device by detaching the modules of the device from each other.

The device is preferably made of an autoclavable-transparent polymeric material. Such amaterial may for instance be polypropylene or polycarbonate, and should preferably allow for both photosynthesis of the plant and reusability of the device after cleaning and autoclaving.

The filling material to be used in the internal third cavity of the middle barrier module, tofixate the seed or seedling within the device, såfeo-ušfiå--as mentioned above also functions as abarrier between the upper and lower compartment modules. The filling material is chosenfrom a group comprising sterile agarose, petroleum gel, wax, paraffin or grease. Optionally asterile tissue material may be comprised in the bottom of the internal third cavity, in order tofacilitate the fixation of a seed therein. The filling material must be applied so that the seed orthe crown area of a seedling is covered in, and embedded in, the material within the thirdinternal cavity. Thereby, microbes present in the above-ground parts may not be transferredby air or water to the below-ground parts, or vice versa, as the filling material will preventsuch transfer or contamination. A microbe would have to move within the plant in order to transfer from above-ground parts to below-ground parts or vice versa Agarose is preferred as the filling material for the middle barrier module. The concentration ofagarose can vary depending on the plant. However, a range between 0.5-2 percent has provento be efficient. The advantage of using agarose is that is dissolves easily in water, making thehandling ofthe material simple. Furthermore, agarose is chemically inert i.e. it does not reactor affect the plant. Agarose is flexible enough to allow the plant to grow and expand withoutbreaking or suffocating the plant. Agarose has a solidification or gelling temperature of 34-38°C, which is an appropriate temperature when working with plants. That means it can beadded to the device when temperature is around 40-45 °C, which does not damage plant cells.A too high or too low solidification or gelling temperature would cause burning or freezinginjuries to the plant cells and possibly kill the plant cells. Furthermore, agarose has a high melting temperature of 90-95 °C. Thus, once the agarose solidifies in the internal third cavity, 9embedding the plant, it is very difficult for it to melt again, without also causing the plant todie. This is important ifthe plant needs to be held at a high temperature for certain experiments or thermothera py.

Solid or gelled agarose creates a mesh of channels with 50 nm to >200 nm depending on theconcentration of agarose used. Higher concentrations yield lower average pore diameters, andis preferable. The small pore sizes with lower pore diameters are suitable in order to inhibitmicrobial cells to pass from the above-ground parts in the upper compartment module to thebelow-ground part in the lower compartment module, or vice versa. The smallest known livingbacterial has an average cell diameter of 0.12-0.20 pm, corresponding to 120 - 200 nm. Asspecified above, a range between 0.5-2 percent agarose has proven to be efficient for this pUFpOSe.

By having the middle barrier detachably attached to the upper and lower compartments, thedevice can be opened at any time after plantation of a seed or seedling from either the uppercompartment module or the lower compartment module, or both. However, in order to maintain germ free conditions for the plant 18this should be done under aseptic conditions. ln order to germinate seeds in the device, a piece of sterile tissue material, such as cotton, ispreferably placed at the bottom of the third internal cavity of the middle barrier module, andthe seed is placed on the top ofthe tissue material. Thereafter the filling material is applied to said cavity, embedding the seed in said filling material.

The use of a tissue material is optional when planting seedlings directly in the device. Aseedling is positioned within the internal third cavity, with the part of the seedling intended togrow above ground towards the top opening of the middle barrier module, and the part of theseedling intended to grow below ground towards the bottom opening ofthe middle barriermodule, where after the filling material is added to the third internal cavity to fixate the seedling at a crown area of said seedling within the middle barrier module.

After placing the seed or seedling in the middle barrier module as described above, the topopening ofthe middle barrier module is attached to or connected with the first bottom wall ofthe upper compartment module. Water or a liquid nutrition solution may be applied into the second cavity of the lower compartment module, and thereafter the bottom opening of the middle barrier module is attached to or connected with the second top wall of the lowercompartment module. Once all three modules have been attached in such a manner, thedevice may be placed under conditions that allows for a plant to grow, or under the conditionsthat are to be studied. lt has no importance if the middle barrier module is first attached tothe upper compartment module, or the lower compartment module. The skilled person will be able to determine which order of attachment is the most appropriate.

The device disclosed herein is simple and versatile. Multiple modifications can be made based on the users' needs.

Two or more devices can be connected through a tube via either the upper compartmentmodule or the lower compartment module. This set-up would make it possible to check ifcertain microbes can move from one plant to another though air, from one uppercompartment module to another, or through soil, from one lower compartment module to another.

Sensors measuring temperature, humidity, pH, 02, C02, etc. can be connected to either theupper compartment module or the lower compartment module, or both. This set-up wouldenable monitoring of the plant's growth, or the plant's response to a treatment. This may onlybe performed when a device is separated from other devices, and not when two or moredevices are connected. A sensor cannot measure plant respiration, such as carbon dioxide oroxygen levels without being influenced by the soil or air of other devices, or the external environment, when multiple devices are connected to each other.

A magnetic stir bar can be added to the lower compartment module when liquid substrate isused, for mixing of said substrate. That might be useful if new treatment is added after the device is closed, that is after the modules have been attached to each other.

The size of the device may vary according to the user's needs. However, the concept of thedevice as disclosed herein remains the same. Thus, any type of plant may be grown in a device such as disclosed herein. The dimensions ofthe device are not limited to small or large plants.

The device may be provided in a kit-of-parts, and optionally a sterile tissue material, as well as instructions for use and maintenance of the device. 11The filling material of the devfice may be chosen from a group comprising sterile agarose, petroleum gel, wax, paraffin or grease, and is preferably agarose.

The device as disclosed herein may for instance be used as a research tool within for instancemicrobial ecology, gnotobiotic studies, study of specific growing conditions for a plant, and for the establishment of a germ-free environment for plant growth.

The present invention will now be described with reference to the accompanying drawings, inwhich preferred example embodiments of the invention are shown. The invention may,however, be embodied in other forms and should not be construed as limited to the hereindisclosed embodiments. The disclosed embodiments are provided to fully convey the scope of the invention to the skilled person.

One embodiment of the device 1 is illustrated in Fig.1. The device 1 comprises an uppercompartment module 2, a lower compartment module 3, and a middle barrier module 4.Within the upper compartment module 2 is a first cavity 8, within the lower compartmentmodule 3 is a second cavity 12, and within the middle barrier module 4 is a third cavity 13. Thedevice 1 has an aperture 19 in the upper compartment module, and two removable plugs 20fitted in apertures (not indicated) in the lower compartment module 3. The longitudinal axis of the device is indicated by the line A-A.

Fig.2 discloses in more detail the components of the embodiment of the device 1 shown in Fig.1. The upper compartment module 2 comprises a first top wall 5, sidewalls 6a, 6b, 6c, 6d, anda first bottom wall 7. The first bottom wall has an aperture 19 for receiving the middle barriermodule 4. ln the present embodiment, the first bottom wall 7 is detachable from the sidewalls6a, 6b, 6c, and 6d. ln the present embodiment, the sidewalls 6a and 6c are provided withapertures. The aperture 19 on sidewall 6a may be fitted with a filter. The aperture on sidewall6c is not shown but provided with a removable plug 20, and this aperture can be used for sampling and manipulating of above-ground parts of a plant positioned within the device.

The middle barrier 4 has a top opening 15 and a bottom opening 16. The lower part of themiddle barrier, immediately adjacent to the bottom opening 16, is funnel shaped, such that the bottom opening 16 is less wide than the top opening 15. 12 The lower compartment module 3 comprises a second top wall 9, sidewalls 10a, 10b, 10c, 10d,and a second bottom wall 11. The second top wall 9 has an aperture 19 for receiving themiddle barrier module 4. ln the present embodiment, the second top wall 9 is detachablefrom the sidewalls 10a, 10b, 10c, and 10d. ln the present embodiment, the sidewalls 10a and10c are provided with apertures 19 (not shown for sidewall 10c) that are each fitted with aplug 20. The aperture 19 on sidewall10a may be used for sampling and manipulation ofthebelow-ground parts of the plant, and for filling or re-filling the second cavity 12 with water ora liquid nutrition solution, as well as adding a substance to the water of nutrition for testing.The aperture 19 not shown on sidewall 10c, but indicated by the plug 20 placed in said aperture, may be used for draining the second cavity 12 and removing any liquid therein.

Fig.3 discloses the device 1 according to the embodiment above, with a plant 18 positionedtherein. The plant is positioned and fixated in the third cavity 13 ofthe middle barrier module,and the grey shadowing in the middle barrier module 4 illustrates the filling material thatfixates the plant in that position. Thus, the plants 18 above-ground parts, here illustrated bythe stem and the leafs, are located in the first cavity 8 ofthe upper compartment module 2,and the plants 18 below-ground parts, here illustrated by a root system, is located in thesecond cavity 12 of the lower compartment module 3. The middle barrier module 4 and thefilling material therein, illustrated by the grey colour, inhibits contact between the first cavity8 and the second cavity 12. Thus, microbes present in the above-ground parts may not betransferred by air or water to the below-ground parts, or vice versa, as the filling material willprevent such transfer or contamination. A microbe would have to move within the plant in order to transfer from above-ground parts to below-ground parts or vice versa.

Also shown in Fig. 3 is an aperture 19 in the upper compartment module 2, for providing the first cavity with air. The aperture may be fitted with a filter.

Fig. 4 is a cross-sectional view along the A-A axis of the arrangement in Fig. 3, with the fillingmaterial 17 fixating the plant 18 clearly indicated within the third cavity 13 ofthe middlebarrier module 4. Thus, the plants 18 above-ground parts, here illustrated by the stem and theleafs, are located in the first cavity 8 ofthe upper compartment module 2, and the plants 18 below-ground parts, here illustrated by a root system, is located in the second cavity 12 of the 13lower compartment module 3. The plug 20, as indicated on sidewall 10c in Fig. 2 is also visible from the inside of the second cavity 12 in this view. ln the embodiment disclosed in the Figs 1-4, the first bottom wall 7 and the second top wall 9are directly adjacent to each other, such that the middle barrier module 4 protrudes into thefirst cavity 8 and into the second cavity 12. lt is possible to design the device so that themiddle barrier module 4 does not protrude, or barely protrudes, into any of the first cavity 8or the second cavity 12, but rather so that the top opening 15 of the middle barrier module 4is at the same height in the device as the first bottom wall 7, and the bottom opening 16 ofthe middle barrier module 4 is at the same height as the second top wall 9. The exact design ofthe arrangement is not of importance as long as the middle barrier module 4 serves thefunction of fixating the plant while isolating the above-ground parts of the plant in the first cavity 8 from the below-ground parts ofthe same plant in the second cavity 12.

Claims (1)

CLAll\/IS

1. A device (1) for growing plants (18) under controlled microbe conditions comprising an upper compartment module (2), adapted for housing above-ground parts of a plant (18),comprising a first top wall (5), at least one side wall (6, 6a, 6b, 6c, 6d), and a first bottomwall (7), said first top wall (5) arranged opposite to said first bottom wall (7), separated ina longitudinal direction (A-A) by said sidewall(s) (6, 6a, 6b, 6c, 6d), such that a first cavity (8) is formed within the upper compartment module (2), a lower compartment module (3), adapted for housing below-ground parts of a plant (18),comprising a second top wall (9), at least one side wall (10, 10a, 10b, 10c, 10d), and asecond bottom wall (11), said second top wall (9) arranged opposite to said secondbottom wall (11), separated in a longitudinal direction (A-A) by said sidewall(s) (10, 10a,10b, 10c, 10d), such that a second cavity (12) is formed within the lower compartment module (3), a middle barrier module (4) adapted to house a seedling or a seed for germination within aninternal third cavity (13) thereof formed by at least one sidewall (14), said middle barriermodule (4) having a top opening (15) and a bottom opening (16) and being extended in a central longitudinal axial direction (A-A) of the device (1), said middle barrier module (4) being arranged between the upper compartment module (2) andthe lower compartment module (3) along a longitudinal central axis (A-A) of the device(1), being connected by the top opening (15) to an aperture (19) in the first bottom wall(7) of the upper compartment module (2) and by the bottom opening (16) to an aperture (19) in the second top wall (9) of the lower compartment module (3), characterised in that the middle barrier module (4) comprises a filling material (17) in which aseed or seedling may be positioned and fixed and which allows growth of said seed orseedling, said filling material (17) substantially isolating the first cavity (8) of the uppercompartment module (2) from the second cavity (12) of the lower compartment module(3), such that the first cavity (8) and the second cavity (12) are not in any fluid communication with each other. The device (1) according to claim 1, wherein the internal third cavity (13) of the middlebarrier module (4) is cone shaped or funnel shaped, such that the top opening (15) of said cavity (13) is wider than the bottom opening (16) of said cavity (13). The device (1) according to any of the claims 1 or 2, wherein the upper compartmentmodule (2) and/or the lower compartment module (3) comprises at least one aperture (19) on a sidewall (6, 6a, 6b, 6c, 6d, 10, 10a, 10b, 10c, 10d). The device (1) according to claim 3, wherein the at least one aperture (19) may be fittedwith any of one or more filter(s), a removable plug (20), an injection port, or a connector to connect the device (1) to a pump. The device (1) according to any ofthe preceding claims, wherein the upper compartmentmodule (2), the lower compartment module (3) and the middle barrier module (4) aremanufactured of an autoclavable, transparent, polymeric material, such as polypropylene or polycarbonate. The device (1) according to any of the preceding claims, wherein the middle barriermodule (4) is detachably attached to the upper compartment module (2) and to the lower compartment module (3). ”n ' -'«^~ . _ QX _89. The device (1) according to any ofthe preceding claims, wherein said filling material (17)is chosen from a group comprising sterile agarose, petroleum gel, wax, paraffin or grease,preferably agarose, and optionally also a sterile tissue material is comprised in the middle barrier module (4). A method of planting and growing germ-free plants (18) using the device (1) according to any of the claims 1-23, comprising performing, in a germ free environment, the steps of: placing a seed or a seedling in thga filling material (17) within the third cavity (13) ofthe middle barrier module (4), wherein Éa seed is positioned on a sterile tissue adjacent to the bottom opening (16) of themiddle barrier module (4) adapted to be connected to the lower compartment module(3), where after the filling material (17) is added to the third cavity (13) of the middle barrier module (4) to encapsulate the seed within the middle barrier module (4), or athf; seedling is positioned within the middle barrier module (4), with the part of theseedling intended to grow above ground towards the top opening (15) of the middlebarrier module (4), and the part ofthe seedling intended to grow below ground towardsthe bottom opening (16) of the middle barrier module (4), where after the filling material(17) is added to the third cavity (13) to fixate the seedling at a crown area of said seedling within the middle barrier module (4); adding water, soil or a liquid nutrition solution into the second cavity (12) of the lower compartment module (3), attaching the top opening (15) of the middle barrier module (4) to the first bottom wall(7) of the upper compartment module (2), and the bottom opening (16) of the middle barrier module (4) to the second top wall (9) of the lower compartment module (3), allowing the seed or seedling to grow. 9%. A kit of parts comprising the device (1) according to any ofthe claims 1-6, wherein the filling material of_tigga_c§_ç_yig;_g__{_1_}__may be chosen from a group comprising sterile agarose, petroleum gel, Wax, paraffin or grease, preferably agarose, _a___rj;_çâ_ vxfraerešra the kit of parts -a-r-æeš--optionally conwgršses a sterile tissue material.