Method and system for growing a plant

Abstract

A method for growing a plant is disclosed. The method comprises providing acetate to the plant as energy and carbon source for biomass production by the plant. The method also comprises providing photosynthetically active radiation (PAR) to the plant as energy source for biomass production by the plant. In the method, the amount of acetate provided to the plant per unit of time and a radiant energy of photosynthetically active radiation provided to the plant per unit of time are varied in dependence on each other.

Description

[0001] 2024PF80495

[0002] 1

[0003] Method and system for growing a plant

[0004] FIELD OF THE INVENTION

[0005] This disclosure relates to a method for growing a plant, in particular to such method wherein an amount of acetate provided to the plant per unit of time and a radiant energy of photosynthetically active radiation provided to the plant per unit of time are varied in dependence on each other. This disclosure further relates to a computer-implemented method, controller, system and computer program for performing such method.

[0006] BACKGROUND OF THE INVENTION EP 2761 990 Bl discloses a plant-cultivating method which comprises a red light irradiation step (A) and a blue light irradiation step (B), wherein the step (A) and the step (B) are independently carried out for a predetermined period of time under cultivation conditions such that amounts of nitrogen, phosphorus and potassium as fertilizer ingredients as used at the step (B) are smaller than amounts of nitrogen, phosphorus and potassium as fertilizer ingredients, respectively, as used at the step (A).

[0007] Publication {A hybrid inorganic-biological artificial photosynthesis system for energy-efficient food production, 2022, Hann et al., Nature Food, Vol. 3, 461-471 } discloses that exogenously supplied acetate incorporates into biomass through major metabolic pathways in crop plants. As known, there is a continuous striving in the art for improving the way plants are grown in Controlled Environment Farming, which may loosely be referred to as indoor farming.

[0008] SUMMARY OF THE INVENTION

[0009] Therefore, a method for growing a plant is disclosed. The method comprises providing acetate to the plant as energy and carbon source for biomass production by the plant. The method also comprises providing photosynthetically active radiation (PAR) to the plant as energy source for biomass production by the plant. In the method, the amount of acetate provided to the plant per unit of time and a radiant energy of photosynthetically active radiation provided to the plant per unit of time are varied in dependence on each other.2024PF80495

[0010] 2

[0011] Arable land for farming is becoming more scarce while the global population is growing, putting food availability at risk. Controlled-environment agriculture (CEA), growing crops indoor in greenhouses and vertical farms, is one of the solutions to ensure food availability. For year-round crop production in greenhouses, especially for regions at higher latitudes, during a large part of the year supplemental horticulture lighting, such as LED lighting, is required, which has an energy cost penalty. In vertical farms even, LED light is typically the sole source of light. Although relatively efficient compared to other type of light sources, LED lighting is a large consumer of energy in greenhouses and vertical farms. In principle, plants can grow efficiently with hardly any light when using acetate as the fuel and source for assimilating carbon. Acetate (as a short chain fatty acid) is an alternative fuel for cellular metabolism. Acetate contributes to the glyoxylate cycle, in which the acetate is converted to malate, which can then be used for energy production. Additionally, acetate can participate in other metabolic pathways, such as the tricarboxylic acid (TCA) cycle, where it enters as acetyl-CoA. The TCA cycle generates ATP and also provides intermediates for biosynthesis. Hence, by providing acetate to the plant as energy and carbon source for biomass production, the energy consumption by light sources may be reduced, especially considering that the production of biomass from acetate assimilation has been found to be far more efficient than the production of biomass from regular photosynthesis from LED sources.

[0012] The production of biomass based on carbon from acetate and the production of biomass based on carbon resulting from photosynthesis are interrelated processes. When acetate is provided to a plant, it can be directly converted into acetyl-CoA by the enzyme acetyl-CoA synthetase. In photosynthesis, plants convert carbon dioxide and water into glucose and oxygen using light. The produced glucose can enter glycolysis, where it is broken down into pyruvate. Pyruvate is then converted into acetyl-CoA. Acetyl-CoA, whether originating from acetate or from photosynthesis, enters the citric acid cycle leading to the production of energy and biosynthetic precursors. Due to the fact that both the provisioning of acetate and the provisioning of photosynthetically active radiation to a plant leads to the production of acetyl-CoA that enters the citric acid cycle, acetate-based biomass production and photosynthesis-based biomass production are interrelated processes. Under given conditions, the citric acid cycle will namely operate at some rate meaning that only some amount of acetyl-CoA will enter the citric acid cycle per unit of time. By varying the amount of acetate provided to the plant per unit of time and the radiant energy of photosynthetically active radiation provided the plant per unit of time in dependence on each2024PF80495

[0013] 3

[0014] other, it can be prevented that acetyl-CoA is produced in excess. The method disclosed herein is advantageous not only in that it prevents undesired accumulation of acetyl-CoA, but also because it enables to prevent that resources, in this case acetate and photosynthetically active radiation, are wasted by providing them to the plant without these resources actually driving the production of biomass. Also, in case only low levels of light happen to be available, e.g., due to cost restrictions or even electrical grid issues, acetate can compensate for the low light levels.

[0015] As referred to herein, radiant energy provided to the plant per unit of time may be expressed as number of photons provided to the plant per unit of time.

[0016] The method may comprise obtaining the acetate that is going to be provided to the plant from waste plant biomass. In indoor farms, where the grow method disclosed herein is preferably performed, such waste is typically abundantly present and the waste can be converted to acetate by biological processes.

[0017] Additionally or alternatively, the method may comprise generating the acetate from CO2 and electrical energy, for example using an electrolyser system disclosed in {A hybrid inorganic-biological artificial photosynthesis system for energy-efficient food production, 2022, Hann et al., Nature Food, Vol. 3, 461-471}. The electrical energy used in this process is preferably generated by a photovoltaic system. Such photovoltaic system may operate based on sunlight, of course, but may also receive excess horticulture light.

[0018] It should be appreciated that varying the amount of acetate provided to the plant per unit of time and the radiant energy of photosynthetically active radiation provided to the plant per unit of time in dependence on each other may be performed by varying the amount of acetate provided to the plant per unit of time in dependence on the radiant energy of photosynthetically active radiation provided to the plant per unit of time, and / or by varying the radiant energy of photosynthetically active radiation provided to the plant per unit of time in dependence on the amount of acetate provided to the plant per unit of time.

[0019] It should be appreciated that some Controlled Environment Farms also use sunlight as PAR source. Of course, if sunlight is used as PAR source, then at least a component of the radiant energy of PAR provided to the plant per unit of time varies uncontrollably, because it depends on, among other things, weather conditions. Varying the amount of acetate provided to the plant per unit of time and the radiant energy of PAR provided to the plant per unit of time in dependence on each other may be performed by varying the amount of acetate provided to the plant per unit of time in dependence of the radiant energy per unit of time of received sunlight.2024PF80495

[0020] 4

[0021] Additionally or alternatively, varying the amount of radiant energy per unit of time provided to the plant may be performed by controlling an amount of radiant energy per unit of time of sunlight that reaches the plant, for example by using a shading system.

[0022] Preferably, the method comprises, during at least one time period, simultaneously providing both acetate and PAR to the plant. This may be beneficial as combining the two energy sources may result in a higher rate of biomass production than would be the case if for example only acetate would be provided to the plant as the single energy source for biomass production. It has been shown by {Fu et al.; Failure to Maintain Acetate Homeostasis by Acetate-Activating Enzymes Impacts Plant Development; Plant Physiology, Volume 182, Issue 3, March 2020, Pages 1256-1271} that high acetate concentrations may lead to an accumulation of acetate within the plant cells that is detrimental to plant growth and development. In addition, this detrimental effect seems to happen before the saturation of the production of acetyl-CoA, the central metabolite in various biosynthetic processes and the important intermediate in both the acetate and photosynthesis pathways. Therefore, the production of biomass via the acetate pathway is limited by the maximum acetate concentration allowed. Therefore, by combining the acetate pathway, e.g. with an acetate concentration up to the maximum allowed concentration, together with the photosynthesis pathway a higher rate of biomass production may be achieved. Further, {Hann, Elizabeth C., et al. "A hybrid inorganic-biological artificial photosynthesis system for energy-efficient food production." Nature food 3.6 (2022): 461-471 } has shown that producing biomass via the acetate pathway is energetically more efficient than via the photosynthesis pathway with LED light. This implies that combining both pathways will also be energetically more efficient than via the photosynthesis pathway alone.

[0023] The method may comprise reducing or increasing the amount of acetate provided to the plant per unit of time, and, based on reducing or increasing the amount of acetate provided to the plant per unit of time, increasing or, respectively, reducing the radiant energy of photosynthetically active radiation provided to the plant per unit of time.

[0024] The method may comprise reducing or increasing the radiant energy of photosynthetically active radiation provided to the plant per unit of time, and, based on reducing or increasing the radiant energy of photosynthetically active radiation provided to the plant per unit of time, increasing or, respectively, reducing the amount of acetate provided to the plant per unit of time.2024PF80495

[0025] 5

[0026] An increase resp. reduction of the radiant energy of the provided PAR per unit of time would typically be accompanied by a reduction resp. increase of the provided amount of acetate per unit of time. Likewise, an increase resp. reduction of the provided amount of acetate per unit of time would typically be accompanied by a reduction resp. increase of the radiant energy of the provided PAR per unit of time. It is not strictly required that the radiant energy of the PAR per unit of time and the amount of acetate provided per unit of time are changed simultaneously, one of the two resources may be changed later and / or slower than the other. Typically, the radiant energy of the PAR per unit of time can be adjusted almost instantly, however, adjusting the amount of acetate provided per unit of time may take more time as this would typically involve changing a concentration of acetate in irrigation water provided to the plant.

[0027] During a first time period, the radiant energy of photosynthetically active radiation provided to the plant per unit of time may have a first value and the amount of acetate provided to the plant per unit of time may have a second value. Also, during a second time period not overlapping with the first time period, the radiant energy of photosynthetically active radiation provided to the plant per unit of time may have a third value and the amount of acetate provided to the plant per unit of time may have a fourth value. In the method disclosed herein, typically, the third value is greater than the first value and the fourth value is smaller than the second value.

[0028] The second time period may occur before or after the first time period.

[0029] Both the first value and the second value may be nonzero values. Additionally or alternatively, both the third value and the fourth value may be nonzero values. In other words, during at least one time period, acetate and photosynthetically active radiation are provided to the plant simultaneously.

[0030] Varying the amount of acetate provided to the plant per unit of time and the radiant energy of PAR provided to the plant per unit of time are varied in dependence on each other may very well involve increasing (or reducing) both. For example, it may be that the biomass production of the plant needs to be boosted for some reason. Then, the amount of acetate provided to the plant per unit of time may be increased to a first value. This first value may be associated with an amount of acetyl-CoA produced per unit of time. However, this amount may still be less than some predetermined maximum amount of acetyl-CoA produced per unit of time. As a result, it may still be effective to increase the radiant energy of the PAR provided to the plant per unit of time as well. In this example, the amount of acetate provided to the plant per unit of time and the radiant energy of PAR provided to the plant per unit of2024PF80495

[0031] 6

[0032] time are varied in dependence on each other. After all, the radiant energy of the PAR provided to the plant per unit of time is only increased after determining that the increase of acetate provided per unit of time leads to an amount of acetyl-CoA produced per unit of time lower than the predetermined maximum amount.

[0033] The first value referred to above may be zero and / or the second value referred to above may be zero.

[0034] In an embodiment, during the second time period referred to above, at least part of the photosynthetically active radiation provided to the plant is provided by one or more artificial light sources. In this embodiment, no photosynthetically active radiation is provided to the plant by an artificial light source during the first time period.

[0035] Thus, the artificial light sources are switched off completely during the first time period. In this first time period, only acetate may be provided to the plant as carbon source.

[0036] The method may involve measuring an amount of a compound of interest, such as a nutritional compound, in the plant, and, based on the measured amount of the compound of interest, changing the amount of acetate provided to the plant per unit of time and changing the radiant energy of photosynthetically active radiation provided to the plant per unit of time.

[0037] Although both acetate and photosynthesis drive biomass production, these two resources are not completely interchangeable. Lighting namely plays an important role in the morphological development of plants and in the development of nutritional content of plants. The radiant energy per unit of time and / or the spectrum of the horticultural lighting that is provided to the plant, influences the plant’s morphological development and the development of nutrients in the plant. Hence, by controlling the radiant energy per unit of time and / or the spectrum of the horticultural lighting, the morphological development of the plant and its nutritional composition development can be controlled to some extent. When lighting is used in this manner, this may be referred to as steering light.

[0038] For example, for leafy vegetables, a high irradiation combined with a high fraction of blue light during the last few days prior to harvest stresses the plants and enhances the nutritional value by producing healthy nutritional compounds (i.e., secondary metabolites such as vitamin C, anthocyanin, flavonoids, etc.). Another example is the application of far-red light during the initial phases of the growth which promotes stretching of the leaves, thereby resulting in a higher light interception and consequently an increase in biomass. So,2024PF80495

[0039] 7

[0040] different growth phases of the plant might lead to different implementation and use of such steering light.

[0041] Based on measuring the amount of a compound of interest, such as vitamin C, in a plant, it may be determined that the radiant energy of the PAR provided to the plant per unit of time needs to be changed in order to stimulate additional production by the plant of this compound of interest. This change may be an increase or a reduction. In any case, this change of PAR radiant energy per unit of time preferably causes a change of amount of acetate provided to the plant per unit of time as well, because the two resources are varied in dependence on each other in the method disclosed herein.

[0042] In an embodiment, the method comprises measuring a height and / or weight of the plant and, based on the measured height and / or weight, changing the amount of acetate provided to the plant per unit of time and changing the radiant energy of photosynthetically active radiation provided to the plant per unit of time.

[0043] In an embodiment, throughout a vegetative growth phase of the plant, the plant uses a first amount of carbon for biomass production, wherein more than 50% of the used first amount of carbon is provided by acetate provided to the plant.

[0044] In this embodiment, acetate is used as the dominant carbon source during the vegetative growth phase. It has been found that acetate is a good carbon source during this phase in which the plant grows significantly, but in which no major morphological or nutritional composition developments occur that cannot be corrected in a later stage using steering light.

[0045] In an embodiment, throughout a growth phase of the plant that occurs after the vegetative growth phase, such as a budding phase or flowering phase or ripening phase, the plant uses a second amount of carbon for biomass production, wherein more than 50% of the used second amount of carbon is carbon that has been fixed by photosynthesis.

[0046] Herein, carbon that has been fixed by photosynthesis refers to the conversion of inorganic carbon (CO2) into organic carbon, such as glucose.

[0047] In this embodiment, photosynthesis is used as the dominant carbon source for biomass production in later growth phases. Photosynthesis is well suited as the carbon source in the final growth stages, where morphological developments occur that may have to be controlled, to some extent, by providing a specific light recipe to the plant in order to steer towards a desired morphology at harvest. The same holds for the nutritional content.

[0048] Varying the amount of acetate provided to the plant per unit of time may comprise varying a concentration of acetate in irrigation water provided to the plant.2024PF80495

[0049] 8

[0050] Additionally or alternatively, varying the amount of acetate provided to the plant per unit of time may comprise varying a concentration of acetate in a growth medium in which the plant is cultivated.

[0051] Varying the radiant energy of PAR provided to the plant per unit of time may be performed by varying the radiant power of PAR provided to the plant, for example by increasing or decreasing the radiant power of PAR that is emitted by one or more light sources.

[0052] One aspect of this disclosure relates to a computer-implemented method comprising steps of

[0053] controlling one or more light sources that are configured to provide photosynthetically active radiation to a plant, for varying a radiant energy of photosynthetically active radiation provided to the plant per unit of time, and controlling an acetate provisioning system that is configured to provide acetate to the plant, for varying an amount of acetate provided to the plant per unit of time. In this method, the one or more light sources and the acetate provisioning system are controlled in dependence on each other such that the amount of acetate provided to the plant per unit of time and the radiant energy of photosynthetically active radiation provided to the plant per unit of time are varied in dependence on each other.

[0054] The computer-implemented method may further comprise obtaining data indicative of an amount of the compound of interest in the plant, e.g. by receiving the signal from a sensor that is configured to measure an amount of a compound of interest in the plant, the signal being indicative of the measured amount of the compound of interest in the plant. The method may than also comprise, based on the indicated amount, determining an appropriate radiant energy of photosynthetically active radiation per unit of time and an appropriate amount of acetate per unit of time, and controlling the one or more light sources to provide the determined, appropriate radiant energy of photosynthetically active radiation to the plant per unit of time and controlling the acetate provisioning system to provide the determined, appropriate amount of acetate per unit of time to the plant.

[0055] The amount of the compound of interest may have been measured manually and a human operator may have input the measured amount into the computer via a user interface. Additionally or alternatively, the computer is connected to a sensor configured to measure the amount of the compound of interest and receives a signal indicative of the measured amount from the sensor.

[0056] The computer-implemented method may further comprise receiving a signal indicative of a height and / or weight of the plant. The method may then also comprise, based2024PF80495

[0057] 9

[0058] on the indicated height and / or weight, determining an appropriate radiant energy of photosynthetically active radiation per unit of time and an appropriate amount of acetate per unit of time, and controlling the one or more light sources to provide the determined, appropriate radiant energy of photosynthetically active radiation to the plant per unit of time and controlling the acetate provisioning system to provide the determined, appropriate amount of acetate per unit of time to the plant.

[0059] The signal indicative of height and / or weight may be input by a human operator into the controller after the human operator has measured the height and / or weight of the plant. Additionally or alternatively, the signal is received from a plant measurement system that is configured to measure the height and / or weight of the plant. For example, such plant measurement system may comprise a camera that is configured to capture an image of the plant, and an image analysis module that is configured to determine the height and / or weight of the plant based on the captured image.

[0060] One aspect of this disclosure relates to a controller for controlling one or more light sources and an acetate provisioning system that is configured to provide an amount of acetate per unit of time to the plant, the controller comprising a processor configured to perform any of the computer-implemented methods described herein.

[0061] The controller would typically also comprise an input interface and an output interface.

[0062] One aspect of this disclosure relates to a system for growing a plant that comprises any of the controllers disclosed herein, any of the one or more light sources referred to herein, and any of the acetate provisioning systems disclosed herein.

[0063] Such system may further comprise any of the sensors disclosed herein that is configured to measure an amount of a compound of interest in the plant, in which case the processor of the system is preferably configured to perform any of the computer-implemented methods disclosed herein that comprises determining, based on a measured amount of the compound of interest, an appropriate radiant energy of PAR per unit of time and an appropriate amount of acetate per unit of time.

[0064] One aspect of this disclosure relates to a computer program comprising instructions which, when the program is executed by a computer, cause the computer to carry out any of the computer-implemented methods disclosed herein.

[0065] One aspect of this disclosure relates to a computer comprising a computer readable storage medium having computer readable program code embodied therewith, and a processor, preferably a microprocessor, coupled to the computer readable storage medium,2024PF80495

[0066] 10

[0067] wherein responsive to executing the computer readable program code, the processor is configured to perform any of the computer-implemented methods disclosed herein.

[0068] One aspect of this disclosure relates to a computer program comprising instructions which, when the program is executed by a computer, cause the computer to carry out any of the computer-implemented methods described herein.

[0069] One aspect of this disclosure relates to a computer-readable data carrier having stored thereon any of the computer programs described herein.

[0070] The computer-readable data carrier may be hard disk, for example, or a signal. One aspect of this disclosure relates to a computer readable storage medium having computer readable program code embodied therewith, and a processor, preferably a microprocessor, coupled to the computer readable storage medium, wherein responsive to executing the computer readable program code, the processor is configured to perform any of the computer-implemented methods described herein.

[0071] One aspect of this disclosure relates to a computer program or suite of computer programs comprising at least one software code portion or a computer program product storing at least one software code portion, the software code portion, when run on a computer system, being configured for executing any of the computer-implemented methods described herein.

[0072] One aspect of this disclosure relates to a non-transitory computer-readable storage medium storing at least one software code portion, the software code portion, when executed or processed by a computer, is configured to perform any of the computer-implemented methods described herein.

[0073] One aspect of this disclosure relates to a data carrier signal carrying any of the computer programs described herein.

[0074] Elements and aspects discussed for or in relation with a particular embodiment may be suitably combined with elements and aspects of other embodiments, unless explicitly stated otherwise. Embodiments of the present invention will be further illustrated with reference to the attached drawings, which schematically will show embodiments according to the invention. It will be understood that the present invention is not in any way restricted to these specific embodiments.

[0075] BRIEF DESCRIPTION OF THE DRAWINGS

[0076] Aspects of the invention will be explained in greater detail by reference to exemplary embodiments shown in the drawings, in which:2024PF80495

[0077] 11

[0078] FIG. 1 illustrates a system for growing a plant according to an embodiment; FIG. 2 is a diagram showing how radiant energy of PAR provided to the plant per unit of time and the amount of acetate provided to the plant per unit of time may be varied according to an embodiment;

[0079] FIG. 3 A is a flow chart illustrating a method for growing a plant according to an embodiment wherein a compound of interest is measured;

[0080] FIG. 3B is a flow chart illustrating a method for growing a plant according to an embodiment wherein a height and / or weight of the plant is measured;

[0081] FIG. 4 is a flow chart illustrating a method for growing a plant;

[0082] FIG. 5 is a graph illustrating a relation between acetate concentration and radiant energy of photosynthetically active radiation provided to the plant per unit of time;

[0083] FIG. 6 is a data processing system according to an embodiment.

[0084] DETAILED DESCRIPTION OF THE DRAWINGS

[0085] In the figures, identical reference numbers indicate identical or similar elements.

[0086] Figure 1 illustrates a system 2 for growing a plant 4a - 4g according to an embodiment. The system 2 comprises a controller 100, light sources 6a - 6d, acetate provisioning system 8, and sensors 10a, 10b.

[0087] The light sources 6a - 6d are configured to provide photosynthetically active radiation (PAR) to the plants 4a - 4g. The provided PAR is an energy source for biomass production by the plants 4a - 4g. A light source as referred to herein may comprise one or more LEDs. Preferably, a light source referred to herein is configured to adjust the radiant power of the PAR that it emits and / or change the spectrum of the light that it emits, under control of the controller 100.

[0088] The acetate provisioning system 8 is configured to provide acetate to the plants 4a - 4g. The acetate provisioning system 8 may comprise an acetate buffer from which acetate can be added to irrigation water 12 that is used to water the plants 4a - 4g. The plants 4a - 4g, in particular the roots 14 of the plants, absorb the acetate when they absorb the irrigation water 12. In vertical farming, for example, it is quite typical that all plant nutrients that are provided to the plants, such as fertilizer, are dissolved in the irrigation water provided to the plants. The ground or soil or substratel6 is typically only used for mechanical anchoring. Providing the acetate via the irrigation water 12 allows for relatively fast and accurate control of the amount of acetate that is provided to the plants per unit of time.2024PF80495

[0089] 12

[0090] Sensors 10a, 10b are configured to measure an amount of a compound of interest in the plants, and output a signal to the controller, wherein the signal is indicative of the measured amount of the compound of interest in the plant. Each sensor 10a, 10b may be a multispectral sensor, such as multispectral camera. Additionally or alternatively, each sensor 10a, 10b may be a near-infrared spectroscopy system. The compound of interest is for example vitamin C or sugar.

[0091] The system 2 may also comprise one or more cameras (not shown) that are configured to capture an image of the plants based on which the height and / or weight of the plants can be determined by an image analysis module.

[0092] The controller 100 is configured to control the one or more light sources 6a -6d for example in that the controller 100 is configured to send instruction signals to the one or more light sources, which signals are indicative of a radiant energy per unit of time of PAR, e.g. indicative of a radiant power of PAR, that the one or more light sources should emit. Additionally or alternatively, the instruction signals indicate that the one or more light sources should switch on or off or should be changed in intensity. This way, the radiant energy of PAR provided to the plant per unit of time may be controlled.

[0093] The controller 100 is also configured to control the acetate provisioning system 8 for varying the amount of acetate provided to the plant per unit of time. The acetate provisioning system 8 may comprise a buffer containing a relatively highly concentrated acetate solution and may comprise a flow control system that is configured to control a flow of the acetate solution from the buffer into the irrigation water 12. This way, the concentration of acetate in the irrigation water may be controlled. The flow control system may comprise one or more valves for controlling the flow. The controller 100 may for example be configured to send instructions signals to the acetate provisioning system 8 which signals are indicative of a flow value, for example in liters / second.

[0094] Further, the controller 100 may be connected to a network 90, such as the internet. The controller may for example be configured to send data to and retrieve data from a server in this network 90.

[0095] Figure 2 is a diagram showing how, according to an embodiment, over the course of a plurality of days, the radiant energy (solid line) provided to the plant per unit of time, in this case per day, may vary and how the amount of acetate (dashed line) provided to the plant per unit of time, in this case per day, may vary.2024PF80495

[0096] 13

[0097] The solid line indicates, for each day, how much radiant energy of PAR is provided to the plant, and the dashed line indicates, for each day, how much acetate is provided to the plant.

[0098] The graph indicates five subsequent time periods I - V. In time period I, a radiant energy Ei is provided to the plant each day, and an amount of acetate V2 each day.

[0099] In time period II, the amount of acetate provided to the plant per day decreases and, based on this decrease, the radiant energy of PAR provided to the plant per day increases. In this example, the amount of acetate may be controlled based on a measured parameter such as on a biomass, which may be measured by measuring the weight and / or height of the plant, and the provided radiant energy of PAR may be adapted based on the provided amount of acetate, as for example explained with reference to figure 3B.

[0100] Alternatively, it may be that the radiant energy of PAR provided to the plant per unit of time is controlled based on a measured parameter, such as on an amount of a compound of interest in the plant, in which case the amount of acetate may be adapted based on the provided radiant energy of PAR, as for example explained with reference to figure 3 A. Alternatively, it may be that an appropriate radiant energy and an appropriate amount of acetate provided per unit of time are determined concurrently taking into account their dependence on each other and based on one or more measured parameters (as explained in figure 4), rather than sequentially where for example the radiant energy is determined based on solely the amount of acetate provide per unit of time or where the amount of acetate is determined based on solely the radiant energy provided per unit of time.

[0101] In time period III, a radiant energy E2 is provided to the plant each day, and an amount of acetate vi each day. Herein, E2 > Ei, and vi < V2.

[0102] In time period IV, the radiant energy of PAR provided to the plant per day decreases, while the amount of acetate provided to the plant per day increases. In time period V, no PAR is provided to the plant and only acetate is provided to the plant.

[0103] The horizontal axis in figure 2 indicates the time in days, however, in another embodiment, the variations that are shown in figure 2 may just as well be performed in a matter of hours. For such embodiment, the graph showing the variations of provided radiant energy per unit of time and provided amount of acetate per unit of time may be identical to the graph shown in figure 2 with the horizontal axis relabeled to show hours instead of days.

[0104] Figure 3 A is a flow chart illustrating a method for growing a plant according to an embodiment. Step 20 comprises measuring an amount of a compound of interest in the plant. This step may be performed by investigating one or more parts of the plants, such as2024PF80495

[0105] 14

[0106] leaves, for example with a multispectral sensor 10a, 10b. Step 22 comprises determining, based on the measured amount, an appropriate radiant energy of PAR to the plant per unit of time. Thereafter, depending on the current value of the radiant energy of PAR provided per unit of time, the radiant energy of PAR provided to the plant per unit of time is increased (step 24) or decreased (step 28). If step 24 is performed, then step 26 is performed which comprises decreasing the amount of acetate provided to the plant per unit of time. If step 28 is performed, then step 30 is performed which comprises increasing the amount of acetate provided to the plant per unit of time. Thereafter, step 20 is performed again. In this embodiment, there is a sequential dependence of the amount of acetate on radiant energy, in that there is a one-way or hierarchical relationship between them. Still, this should be understood as that the amount of acetate provided to the plant per unit of time and the radiant energy of photosynthetically active radiation provided to the plant per unit of time are varied in dependence on each other. Further, in this embodiment, the amount of acetate provided to the plant may be understood as being determined based on the measured amount of the compound of interest as measured in step 20.

[0107] Figure 3B is a flow chart illustrating a method growing a plant according to an embodiment. Step 32 comprises measuring a weight and / or height of the plant and step 34 comprises determining, based on the measured weight and / or height, an appropriate amount of acetate to be provided to the plant per unit of time. Then, depending on the current value of the provided amount of acetate per unit of time, the amount of acetate provided per unit of time is increased (step 30) or decreased (step 26). If step 30 is performed, then step 28 is performed which comprises decreasing the radiant energy of PAR provided to the plant per unit of time. If step 26 is performed, then step 24 is performed which comprises increasing the radiant energy of PAR provided to the plant per unit of time. Thereafter, step 32 is performed again. In this embodiment, there is a sequential dependence of radiant energy on the amount of acetate, in that there is a one-way or hierarchical relationship between them. Still, this should be understood as that the amount of acetate provided to the plant per unit of time and the radiant energy of photosynthetically active radiation provided to the plant per unit of time are varied in dependence on each other. Further, in this embodiment, the radiant energy of PAR provided to the plant per unit of time may be understood as being determined based on the measured weight and / or h height as measured in step 32.

[0108] Figure 4 is a flow chart illustrating a method according to an embodiment. Step 40 comprises measuring the amount of the compound of interest in the plant and / or measuring the weight and / or height of the plant. Then, in step 42, an appropriate amount of2024PF80495

[0109] 15

[0110] radiant energy to be provided to the plant per unit of time and an appropriate amount of acetate to be provided to the plant per unit of time are determined. In this step, the dependence between these two parameter values are taken into account. For example, it may be ensured in step 42 that the combination of the provided radiant energy of PAR per unit of time and the amount of acetate provided per unit of time does not cause an excess of acetyl-CoA in the plant. Thereafter, step 44 is performed which comprises actually providing the determined appropriate radiant energy to the plant per unit of time as well as the determined appropriate amount of acetate to the plant per unit of time.

[0111] Figure 5 is a graph illustrating a concrete relation between acetate concentration in the growth medium or irrigation water expressed as millimole per liter, and irradiance expressed as number of pmole photons per m2per second. Acetate uptake by the plant is proportional to the maintained acetate concentration in the growth medium or irrigation water. This means there is a direct proportional relation between acetate concentration and the amount of acetate provided to the plant per unit of time. Hence, the concentration of acetate in irrigation water provided to the plant may be taken as a measure for the amount of acetate provided to the plant per unit of time and varying the amount of acetate provided to the plant per unit of time may be performed by varying the acetate concentration in irrigation water that is provided to the plant. The solid line represents a preferred relation whereas the dark shaded area (between 0 and 70 millimole / liter) indicates the combinations of irradiance value and acetate concentration value that are also acceptable. Generally, as the concentration of acetate increases, the acetate uptake by plants also increases up to a certain point. This is because plants have specific enzymes, such as acetyl-CoA synthetase, that help in the uptake and utilization of acetate. However, if the acetate concentration becomes too high, it leads to an accumulation of acetate within the plant cells, which is detrimental to plant growth and development. This is because excess acetate can disrupt cellular homeostasis and metabolic processes. See {Fu et al.; Failure to Maintain Acetate Homeostasis by Acetate-Activating Enzymes Impacts Plant Development; Plant Physiology, Volume 182, Issue 3, March 2020, Pages 1256-1271}. Hence, too high concentrations are to be avoided. The graph of figure 5, by means of the light grey area, for example indicates that acetate concentrations higher than 70 millimole / liter are preferably avoided.

[0112] Figure 6 schematically illustrates a data processing system 100, also referred to as a computer, according to an embodiment. The data processing system 100 may for example represent a controller and / or a server as described herein.2024PF80495

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[0114] In data processing system 100, a system bus 102 connects the different components of the data processing system 100. In particular, the system bus 102 depicted in figure 6 connects the Central Processing Unit (CPU) 104, memory elements 106, input devices 108, output devices 110 and communication devices 112 with each other so that they can exchange information. The system bus 102 may be understood to serve both as data bus, address bus and control bus known in the art.

[0115] The CPU 104 is configured to perform steps as per the instructions comprised in a computer program. To illustrate, based on such instructions, the CPU may perform any of the computer-implemented methods described herein. Typically, the CPU 104 is embodied as a microprocessor, which can be implemented on a single metal-oxide-semiconductor integrated circuit chip. The CPU 104 comprises a control unit 114, an arithmetic logical unit (ALU) 116 and a plurality of registers 118.

[0116] The control unit 114 is configured to retrieve instructions from a main memory 120. Typically, the control unit 114 comprises a binary decoder to convert the retrieved instructions into timing and control signals that direct the operation of for example the ALU 116. ALU 116 is configured to perform logical operations, such as additions, subtraction, multiplication, division and Boolean operations, that are required for carrying out the instructions. The registers 118 are small memory elements that can be read and written at relatively high speed. A register may for example store an instruction, a storage address, or any other kind of data. In addition, the CPU may contain hardware caches known in the art (not shown). Preferably the CPU has different levels of caches. These hardware caches may be understood as an intermediate state between the faster registers 119 and the slower main memory 120.

[0117] Memory elements 106 comprise a main memory 120. The main memory 120, also referred to as primary storage in the art, has stored data that is directly accessible to the CPU 104. The CPU 104 may continuously read instructions, i.e. read computer programs, stored in the main memory 120 and execute these instructions. The main memory 120 is typically a random access memory (RAM).

[0118] Memory elements 106 further comprise so-called secondary storage 122, which may be embodied as one or more hard disk drives and / or as one or more solid state drives. Typically, these secondary storage is non-volatile. Further, the memory elements may comprise other storage devices 124, such as removable storage devices, e.g. CD, DVD, USB flash drives, floppy disks, et cetera.2024PF80495

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[0120] Input devices 108 may be understood as devices that are used to provide information to the computer 100, in particular to the CPU 104. Non-limiting examples of input devices are a keyboard, a microphone, a joystick, a mouse, a touch sensitive screen, a sensor that is configured an amount of a compound of interest referred to herein, et cetera. Output devices 110 may be understood as devices that output information out of the computer and / or as devices that are controlled by the computer. Non-limiting examples of output devices 110 are a display, a printer, a headphones, loudspeaker, an acetate provisioning system referred to herein, a light source referred to herein, any of the actuators referred to herein, et cetera.

[0121] Communication devices 112 may be understood as devices that allow the computer system to communicate with other computers, such as with a server computer, client computer, or any other type of remote device. Non-limiting examples of communication devices 112 include modems, cable modems, ethernet cards, Bluetooth modules, et cetera.

[0122] The controller 100 may be implemented in a unit separate from the sensor, such as a wall panel, a desktop computer terminal, or even a portable terminal, such as a laptop, a tablet, or a smartphone.

[0123] Alternatively the controller may be incorporated into the same unit as the sensor and / or the same unit as the luminaire. Further, the controller 100 may be implemented in the environment or remote from the environment (for example, on a server of the building or even outside the building at a different geographical site); and the controller 100 may be implemented in a single unit or in the form of distributed functionality distributed amongst multiple separate units (for example, a distributed server comprising multiple server units at one or more geographical sites, or a distributed control function distributed amongst the luminaires or amongst the luminaires and the sensor).

[0124] Furthermore, the controller 100 may be implemented in the form of software stored on a memory (comprising one or more memory devices) and arranged for execution on a processor (comprising one or more processing units), or the controller 100 may be implemented in the form of dedicated hardware circuitry, or configurable or reconfigurable circuitry, such as a PGA or FPGA, or any combination of these.

[0125] Regarding the various communication involved in implementing the functionality discussed below, to enable the controller 100 to receive the sensor readings from the sensor and to control the light output of the luminaire, these may be implemented in by any suitable wired and / or wireless means, for example, by means of a wired network, such2024PF80495

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[0127] as an ethernet network, a DMX network or the Internet, or by means of a wireless network, such as a local (short range) RF network, for example, a Wi-Fi, ZigBee or Bluetooth network, or any combination of these and / or other means.

[0128] While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. The invention is not limited to the disclosed embodiments.

[0129] Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims.

[0130] In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality.

[0131] A single processor or other unit may fulfill the functions of several items recited in the claims.

[0132] The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to obtain an advantage.

[0133] A computer program may be stored / distributed on a suitable medium, such as an optical storage medium or a solid-state medium supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems.

[0134] Any reference signs in the claims should not be construed as limiting the scope.

Claims

2024PF8049519CLAIMS1. A method for growing a plant, the method comprisingproviding acetate to the plant as energy and carbon source for biomass production by the plant, andproviding photosynthetically active radiation to the plant as energy source for biomass production by the plant, whereinan amount of acetate provided to the plant per unit of time and a radiant energy of photosynthetically active radiation provided to the plant per unit of time are varied in dependence on each other.

2. The method according to claim 1, further comprisingreducing or increasing the amount of acetate provided to the plant per unit of time, andbased on reducing or increasing the amount of acetate provided to the plant per unit of time, increasing or, respectively, reducing the radiant energy of photosynthetically active radiation provided to the plant per unit of time.

3. The method according to claim 1 or 2, further comprisingreducing or increasing the radiant energy of photosynthetically active radiation provided to the plant per unit of time, andbased on reducing or increasing the radiant energy of photosynthetically active radiation provided to the plant per unit of time, increasing or, respectively, reducing the amount of acetate provided to the plant per unit of time.

4. The method according to any one of the preceding claims, whereinduring a first time period, the radiant energy of photosynthetically active radiation provided to the plant per unit of time has a first value and the amount of acetate provided to the plant per unit of time has a second value, and whereinduring a second time period not overlapping with the first time period, the radiant energy of photosynthetically active radiation provided to the plant per unit of time has2024PF8049520a third value and the amount of acetate provided to the plant per unit of time has a fourth value, whereinthe third value is greater than the first value and the fourth value is smaller than the second value.

5. The method according to claim 4, whereinat least part of the photosynthetically active radiation provided to the plant during the second time period, is provided by one or more artificial light sources, and whereinno photosynthetically active radiation is provided to the plant by an artificial light source during the first time period.

6. The method according to any one of the preceding claims, further comprising measuring an amount of a compound of interest, such as a nutritional compound, in the plant, andbased on the measured amount of the compound of interest, changing the amount of acetate provided to the plant per unit of time and changing the radiant energy of photosynthetically active radiation provided to the plant per unit of time.

7. The method according to any one of the preceding claims, wherein throughout a vegetative growth phase of the plant, the plant uses a first amount of carbon for biomass production, whereinmore than 50% of the used first amount of carbon is provided by acetate provided to the plant.

8. The method according to claim 7, whereinthroughout a growth phase of the plant that occurs after the vegetative growth phase, such as a budding phase or flowering phase or ripening phase, the plant uses a second amount of carbon for biomass production, whereinmore than 50% of the used second amount of carbon is carbon that has been fixed by photosynthesis.2024PF80495219. The method according to any one of the preceding claims, wherein varying the amount of acetate provided to the plant per unit of time comprises varying a concentration of acetate in irrigation water provided to the plant.

10. A computer-implemented method using a controller for controlling one or more light sources and an acetate provisioning system that is configured to provide an amount of acetate per unit of time to the plant, the method comprising the steps of- controlling, by the controller, one or more light sources that are configured to provide photosynthetically active radiation to a plant, for varying a radiant energy of photosynthetically active radiation provided to the plant per unit of time, and- controlling, by the controller, an acetate provisioning system that is configured to provide acetate to the plant, for varying an amount of acetate provided to the plant per unit of time, whereinthe one or more light sources and the acetate provisioning system are controlled, by the controller, in dependence on each other such that the amount of acetate provided to the plant per unit of time and the radiant energy of photosynthetically active radiation provided to the plant per unit of time are varied in dependence on each other.

11. The computer-implemented method according to claim 10, further comprising obtaining, by the controller, data indicative of an amount of the compound of interest in the plant, e.g. by receiving a signal from a sensor that is configured to measure an amount of a compound of interest in the plant, andbased on the indicated amount, determining, by the controller, an appropriate radiant energy of photosynthetically active radiation per unit of time and an appropriate amount of acetate per unit of time, andcontrolling, by the controller, the one or more light sources to provide the determined, appropriate radiant energy of photosynthetically active radiation to the plant per unit of time and controlling the acetate provisioning system to provide the determined, appropriate amount of acetate per unit of time to the plant.

12. A controller for controlling one or more light sources and an acetate provisioning system that is configured to provide an amount of acetate per unit of time to the plant, the controller comprising a processor configured to perform the computer-implemented method according to claim 10 or 11.2024PF804952213. A system for growing a plant, the system comprisingthe controller according to claim 12, andthe one or more light sources referred to in claim 12, andthe acetate provisioning system referred to in claim 12.

14. The system according to claim 13, further comprisingthe sensor referred to in claim 11, whereinthe processor of the controller is configured to perform the method according to claim 11.

15. A computer program comprising instructions which, when the program is executed by a controller according to claim 12, cause the controller to carry out the computer-implemented method according to claim 10 or 11.

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