A small-scale delivery system of a nutrient solution for increasing inflorescences and cannabinoid yield, and a method for increasing the inflorescences and cannabinoid yield of cannabis plants

Abstract

The invention relates to a small-scale delivery system of a nutrient solution for increasing inflorescences and cannabinoid yield of cannabis plants and a method thereof, wherein the nutrient solution is a water solution of saccharides in their preferred amounts, while other nutrients can be optionally present. The delivery system comprises at least one container filled with the nutrient solution, a dosing device and infusion means. The dosing device pushes the solution out of the container and into the cannabis plant through the infusion means over a determined time period. The method according to the invention uses plant stem infusion for delivery of the nutrient solution into cannabis plants via a defined flow regime. The cannabinoid yield in the cannabis plant increased up to 34 wt.% compared control plants.

Description

[0001] A small-scale delivery system of a nutrient solution for increasing inflorescences and cannabinoid yield, and a method for increasing the inflorescences and cannabinoid yield of cannabis plants

[0002] The first aspect of the invention is a small-scale delivery system of a nutrient solution for increasing inflorescences and cannabinoid yield of cannabis plants. The delivery system comprises at least one container filled with a nutrient solution for increasing inflorescences and cannabinoid yield, a dosing device and infusion means. The dosing device pushes the solution out of the container and into the cannabis plant through the infusion means over a period of multiple days, which increases the inflorescences and cannabinoid yield in the cannabis plant, when the product is harvested.

[0003] The second aspect of the invention is a method for increasing the inflorescences and cannabinoid yield of cannabis plants, wherein the solution is delivered into cannabis plants via plant stem infusion over determined time period via a defined flow regime.

[0004] The third aspect of the invention is the use of the solution for increasing the inflorescences and cannabinoid yield of cannabis plants according to the proposed method.

[0005] The cannabinoid yield in the cannabis plant increased up to 34 wt.% using the delivery system with the solution, and the method according to the invention, compared to non-infused control plants.

[0006] The demand for high-quality cannabis has surged in both the medicinal and recreational markets. Maximizing yield and enhancing the quality of cannabis plants, particularly by increasing the content of secondary metabolites such as cannabinoids involves several challenges. Traditional methods of nutrient delivery, such as drenching, fertigation, and foliar feeding, even when paired with plant-growth- promoting rhizobacteria, often fall short in maximizing plant production potential due to limitations in nutrient absorption and distribution.

[0007] One of the methods to deliver different compounds into plants (e.g., nutrients, pesticides, vitamins, hormones, etc.) is plant stem infusion. Several unsolved challenges are associated with the plant stem infusion method. Although it is more effective than foliar feeding (Zhou 1996), the efficiency of infusion, measured by the total volume of the injected infusion solution, heavily depends on applied pressure, solution content (concentration, osmolarity, and pH), number of injection sites, and salt stress (Khan 2016; Zhou 1996, 1997, 1999; Abdin 1998; Boyle 1991). These challenges are not well understood and are poorly researched.

[0008] Sucrose was already used as a nutrient in different studies of plant stem infusion, to enhance plant growth in various crops, including maize (Boyle 1991 ; Zhou 1996, 1999), barley and wheat (Ma 1995), soybean (Abdin 1998), sweet potato (Tsubone 2000; Kadowaki 2001), chickpea (Khan 2016), and bonsai trees (Zhang 2023). To the best of the applicant’s knowledge, the stem infusion method has not been used with cannabis plants nor was a dedicated delivery system developed. The optimal conditions for increasing inflorescences and cannabinoid yield of cannabis plants are not known and are difficult to assess. Furthermore, sufficient flow rate of the nutrient solution into the cannabis plant should be assured, while blockage, leakage or damage to the cannabis plant should be avoided or minimized. A delivery system, composition of the nutrient solution and a method of infusion of such solution, which would provide a positive effect on inflorescence and on the yield of desired products needs to be carefully designed. Also, no routine set of experiments is known for such design. The position, angle, depth and diameter of injection means, e.g. a hollow needle, which is inserted into the cannabis plant should also be addressed. Another important aspect to consider is choosing the targeted tonicity and / or osmolarity of the nutrient solution in order to be adsorbed by the plant efficiently and to avoid osmotic stress in the cannabis plant. While the exact tonicity of Cannabis phloem is unknown a typical plant osmolarity between 0.2 and 0.5 Osm / L can be assumed.

[0009] The delivery system of a nutrient solution, the method for increasing the inflorescences and cannabinoid yield of cannabis plants and the use of the nutrient solution according to this invention provide a novel approach for increasing the inflorescences and cannabinoid yield of cannabis plants and overcomes the mentioned challenges, identified for other plants. The cannabis plant differs from already tested plants where the plant stem infusion was used, in that the stem composition, thickness, and vascular system are distinct. For example, the quantity and direction of fibres, the position of phloem and xylem in the stem, nutrient needs and their adsorption, osmolarity, growth rate, stem thickening rate, stem hardness and flexibility, capillary action all differ compared to other plants tested so far. The delivery system of a nutrient solution and the method of the invention are therefore specifically designed for cannabis plants and, offer controlled dosing of the nutrient solution during a prolonged time frame, i.e. multiple days, weeks or months. The delivery system is particularly suitable for small-scale use at home or in a small setting. Alternatively, multiple such delivery systems can be used in a larger setting or for industrial use. Depending on the embodiment, the delivery system can simultaneously deliver the solution into a plurality of cannabis plants, providing further automation and ease of use for the user of such systems. It is designed for growing up to nine cannabis plants per delivery system. The solution according to the invention is a water solution of saccharides, preferably sucrose. Preferably, the solution with a saccharide content between 1 wt.% to 50 wt.% is infused at a flow rate between 0.02 mL / day to 7,74 mL / day into the stem of the cannabis plant, resulting in a substantial increase in the cannabinoid yield at the time of harvest.

[0010] In the context of this application the terms “nutrient solution” and “solution” are used interchangeably and referring to an aqueous solution, comprising any saccharide, suitable for delivery into the cannabis plant and increases the inflorescences and cannabinoid yield. The concentration is defined as a mass fraction of saccharide / saccharides in the water in per cent, unless defined otherwise. Further metabolites, including micro and macronutrients, growth factors, hormones, enzymes, fertilizers, pesticides, and other metabolically active compounds can be present in the solution.

[0011] The invention is described in more detail below and presented in the figures showing:

[0012] Fig. 1 Schematical representation of one embodiment of the delivery system with one container

[0013] Fig. 2 Schematical representation of one embodiment of the dosing device, comprising a holder for three containers and a release button.

[0014] Fig. 3 Cumulative injected volume overtime at infusion conditions, grouped by applied pressure

[0015] Fig. 4 Average cannabinoid yield per plant at different flow rates and saccharide concentrations

[0016] Fig. 5 Cannabinoid yield, dry flower mass and dry plant mass per plant at different applied pressures and saccharide concentrations

[0017] The delivery system

[0018] The delivery system according to the invention comprises at least one container 1 filled with a solution 1.1 for increasing the inflorescences and cannabinoid yield of cannabis plants, a dosing device 2 and an infusion means 3, wherein the dosing device 2 is adapted to hold at least one container 1 , and the infusion means 3 is connectable to the container 1 at its first end and is inserted into the stem of the cannabis plant at its second end, enabling the flow of the solution T .1 into the cannabis plant. One of the embodiments of the delivery system is shown in figure 1 .

[0019] The solution and the container

[0020] The solution 1.1 for increasing the inflorescences and cannabinoid yield of cannabis plants according to the invention is a water solution of at least one type of saccharide or combination of different types of saccharides, wherein the concentration of the solution 1.1 is such as to assure osmolarity of 1.5 Osm / L at maximum, enabling efficient saccharide adsorption and avoiding excessive osmotic stress. For example, the osmolarity of approximately 1.5 Osm / L corresponds to a solution 1.1 containing approximately 50 wt.% of sucrose. No minimum osmolarity is necessary, as pure water was also found to have a positive effect on the yields at low flow rates. Preferably the osmolarity of the solution 1.1 is between 0.2 Osm / L and 0.9 Osm / L, which corresponds to the concentration between 7.5 wt.% and 30 wt.% for sucrose. Any saccharide or a combination thereof, which is soluble in water at room temperature, provides appropriate osmolarity, and can be metabolized by the cannabis plant is suitable for use. Preferably, monosaccharides or disaccharides, e.g. sucrose, fructose, glucose, ribose, lactose or maltose, are used. More complex saccharides, e.g. amylose, amylopectin, cellulose, galactogen, inulin or maltodextrin, can also be used, if the requirements regarding solubility, osmolarity and metabolism are met. The solution 1.1 is preferably stored in a container 1 to avoid contamination and is ready to use within the delivery system. The container comprises a barrel 1 .2 to hold the solution 1 .1 , a plunger 1 .3 to push the solution 1.1 out and a hub 1.4 to allow the solution 1.1 to flow out of the container. The container 1 is preferably a syringe.

[0021] In some embodiments, the solution 1.1 can additionally contain other plant nutrients, preferably in the form of water-soluble salts, which are commonly present in fertilizers, plant growth regulators, amino acids or plant hormones, Preferably, water-soluble salts, containing potassium, nitrogen and / or phosphorus can be used.

[0022] In a preferred embodiment, the added nutrients or their equivalent salts, are chosen from the list in Table 1 , preferably below the provided concentration limits, to provide a positive effect.

[0023] Table 1. List of preferable nutrients, which can be added to the solution 1.1 and their maximum concentration limits.

[0024] The benefit of using plant nutrients in the solution 1 .1 is the avoidance of classical fertilization methods, which provide nutrients through the root system of the plant, whereby nutrient losses are further minimized, and additional ease of use is provided.

[0025] The dosing device

[0026] The dosing device 2 comprises fluid promotion means 2.1 , e.g. a mechanical motor or pump, a housing 2.2, a holder 2.3 for holding at least one container, a power supply, e.g. a section for inserting batteries or an electrical cable, and a controller 2.4 for controlling the flow rate. Preferably, the dosing device 2 is a syringe pump, wherein the container 1 to be used with the dosing device 2 is a syringe.

[0027] The fluid promotion means 2.1 is configured to ensure fluid flow rate in the range 0.02 to 7,74 mL / day, preferably in the range between 0,06 to 5,23 mL / day, more preferably in the range between 0.2 to 2 mL / day into individual cannabis plant. In a preferred embodiment, shown on figure 2, a stepper motor 2.1.1 , connected to a pusher block 2.1.2 via a pushing means 2.1.3, e.g. a gear mechanism connected to a rotating rod, is used as fluid promotion means 2.1 for enabling such a flow rate. The stepper motor 2.1 .1 is adapted to push the pusher block 2.1 .2 at a preferred rate, which further pushes the plunger 1 .3 of each container 1 , when in operation. The holder 2.3 can hold at least one container 1 . In some embodiments the holder 2.3 can hold up to nine containers 1 , preferably between two and six containers 1. In such cases, the fluid promotion means 2.1 pushes the plungers 1.3 of all containers 1 simultaneously, e.g. by using a pusher block 2.1.2, enabling essentially the same flow rate from all containers 1 , all else being equal. The housing 2.2 is preferably designed to protect the electrical parts of the device from liquids, e.g. by covering the mechanical motor. The holder 2.3 is adapted to hold the barrel 1 .2 of each container 1 fixed to the dosing device 2.

[0028] In a preferred embodiment shown on figure 2, the dosing device 2 additionally comprises a manual release button 2.5 for releasing and resetting the pusher block 2.1.2 so it can be manually repositioned to insert full containers 1 after removing the depleted containers 1. In one embodiment, where the pusher block 2.1.2 is pushed by a motor via a rotating rod with a spiral groove, the release button 2.5 pushes the pusher block 2.1.2 at one end out of the groove, so it can be manually repositioned. After repositioning, the pusher block 2.1.2 is re-inserted into the groove. The controller 2.4 is preferably preprogramed to specified flow rates.

[0029] The infusion means

[0030] The infusion means 3 of each individual container 1 is comprised of a tube 3.1 and injection means 3.2. The tube 3.1 is at one end adapted to be attached to the hub of the container 1. At the other end, the tube 3.1 is attached to injection means 3.2. The injection means 3.2 is preferably in the form of a cannula or a hollow needle, e.g. a hypodermic needle, and configured for inserting into the stem of the cannabis plant, the stem diameter being in the range between 3 mm and 10 mm. To avoid blocking the flow rate and to avoid making extensive damage to the stem, the injection means 3.2 should have a suitable gauge number, preferably between G14 and G26. The most suitable gauge number is between G18 and G23. The cannula is particularly suitable for injection of the solution 1.1 into cannabis plant, having a blunt tip and infusing the solution 1.1 from the side wall of the cannula into the cannabis plant, lowering the probability of plant damage and blockage. The injection means 3.2 can optionally be in the form of a microneedle patch.

[0031] Method

[0032] The method according to the invention uses plant stem infusion for delivery of the solution 1.1 for increasing the cannabinoid yield into the stem of the cannabis plant or plurality thereof, following a prescribed flow regime. Preferably, but not limited to, the delivery system according to the invention is used. The method comprises dosing of a solution 1.1 according to the invention into the stem of at least one cannabis plant through the infusion means 3, when the stem diameter is at least 3mm. The solution 1.1 is a water solution 1.1 of at least one type of saccharide or combination of different types of saccharides with osmolarity of 1.5 Osm / L at maximum. No minimum osmolarity is necessary, as water was also found to have some positive effect on the yields. This is probably due to the use of the plant stem infusion in comparison to obtaining water through the roots. Preferably, the concentration of saccharides is in the range between 1 wt.% and 50 wt.%. Most preferably, the concentration of saccharides is in the range between 7.5 wt.% and 30 wt.%.

[0033] The effect of infused saccharides into plants is not widely researched and not well known. One of the possible explanations of the infusion of the solution with saccharides into a cannabis plant is that the addition of saccharides lowers the overall photosynthetic activity. This is reasonable, considering that photosynthesis is the process of producing saccharide molecules, which can be abundant in this case. Consequently, the overall growth of the plant can be faster, the stem can grow wider, and the flowers - inflorescences can grow bigger. The cannabinoid yield was also observed to increase significantly, depending on the flow rate regime used. Infused saccharides can have a twofold effect on the plant. They can act as an energy source but also as a signalling molecule.

[0034] Flow rates into individual cannabis plants in the range 0.02 to 7,74 mL / day, preferably in the range between 0,06 to 5,23 mL / day, more preferably in the range between 0.2 to 2.0 mL / day are used.

[0035] In one embodiment the solution is infused with a constant flow rate regime over the infusion time. The constant flow rate during the total infusion time is preferably in the range between 0.06 mL / day to 2.85 mL / day.

[0036] In another embodiment the solution is infused with a variable flow rate regime over the infusion time, for example the flow rate is initially high and is lowered sequentially or vice versa.

[0037] Alternatively, pressure can be used to regulate the flow rates. The pressure applied to the solution 1.1 was found to be suitable in the range between 0.5 bar and 2 bar, preferably in the range between 0.5 and 1 bar. However, different applied pressures, e.g. between 0.1 and 10 bar, can be applied to the solution 1.1 , depending on the delivery system, e.g. the inner diameter of the infusion means 3 or if multiple injection sites are used at any one plant, which alters the corresponding flow rates into each cannabis plant.

[0038] The infusion time is at least 24 hours.

[0039] In one embodiment of the method, the delivery system according to the invention is used, wherein the method involves the following steps:

[0040] • the injection means 3.2 is inserted into the stem of the cannabis plant, preferably into the node at an angle of 10° to 30° according to the stem, from above, when the stem diameter is at least 3mm;

[0041] • at least one container 1 is inserted into the holder 2.3 of the dosing device 2;

[0042] • the infusion means 3 is connected to at least one container 1 ;

[0043] • the dosing device 2 pushes the solution 1.1 into the cannabis plant at a predetermined flow rate, preferably in the range between 0.02 mL / day and 7,74 mL / day or applied pressure in the range between 0.5 and 2 bar.

[0044] In one of the embodiments, the solution 1 .1 is infused at an average flow rate between 0.06 mL / day and 2.85 mL / day into individual cannabis plant through infusion means 3. Preferably, the solution 1.1 is infused for at least 2 days or until the cannabis plant is ready for harvest. More preferably, the solution 1 .1 is infused for at least 14 days.

[0045] In one of the embodiments, the solution 1 .1 is infused at an average flow rate between 0.20 mL / day and 2.00 mL / day into individual cannabis plant through infusion means 3. Preferably, the solution 1.1 is infused for at least two days or until the cannabis plant is ready for harvest. More preferably, the solution 1 .1 is infused for at least two weeks.

[0046] In one of the embodiments, the solution 1.1 is infused at a flow rate between 0.66 mL / day and

[0047] 2.85 mL / day in the first 24 hours after injection.

[0048] In one of the embodiments, the solution 1.1 is infused at a flow rate between 0.53 mL / day and

[0049] 1 .86 mL / day in the first 48 hours after injection.

[0050] In one of the embodiments, the solution 1.1 is infused in two consecutive flow regimes, wherein in the first 24 hours, the solution 1.1 is infused at a flow higher flow rate up to 2.86 mL / day and is gradually decreased at least in the following two days to a flow rate below 1 .0 mL / day.

[0051] In one of the embodiments, the solution 1.1 is infused in two consecutive flow regimes, wherein in the first 48 hours, the solution 1.1 is infused a flow rate between 0.53 mL / day and 1.86 mL / day, followed by a flow rate between 0.06 mL / day and 0.20 mL / day for at least the following two weeks.

[0052] In one of the embodiments, the solution 1 .1 is infused in a ramp-up flow regime, starting with lower flow rate in the first 24 hours, and is gradually increased at least in the following two days up to 2 mL / day.

[0053] Experiments

[0054] Experimental results of plant stem infusion into cannabis plants are provided below, to support the benefits of the mentioned operating conditions and the composition of the solution. The results further suggest that the operating conditions could have a fatal effect on the plant, if the dosing of the solution is not controlled within the fluid flow rate range between 0.02 to 7.74 mL / day. An experimental delivery system was used to control and measure operating parameters, e.g. applied pressure and flow rate among others. The delivery system according to the invention was designed based on these results and offers controlled dosing into each plant at operating conditions, which were found optimal.

[0055] Various water solutions of sucrose, containing 0%, 7.5%, 15%, and 30% by weight were infused into multiple cannabis plants at applied pressure on the liquid surface between 0.5 bar and 2 bar, to provide a targeted flow rate between 0.02 to 7,74 mL / day or an average flow rate between 0.06 mL / day to 2.85 mL / day over multiple days. Additionally, a negative control group of plants without infusion was included.

[0056] One genotype of the variety Charlotte’s Angel®, a chemical phenotype (chemotype) III was used in the study. Mother plants were cultivated under common growth conditions. Plants were irrigated according to the Aptus nutrient schedule for vegetative growth. After the plants reached a stem width of at least 3 mm, i.e. on day 70 and roughly when the flowering phase started, each of the test plants was injected with a standard hypodermic needle (20G, 0.9 mm external diameter), which was connected to the corresponding containers 1 of the experimental delivery system via tubing. The needle was injected diagonally in the bottom-most node of each test plant. The diagonal injection at an angle between 10° and 30° according to the stem provides an additional benefit for dosing into the plant. A pressure of 0.5 bar, 1 bar, or 2 bar was applied to the solution in containers 1 and maintained over multiple days, to provide the targeted flow rates of the solution into the corresponding cannabis plants. The volume of the solution in the containers 1 was periodically measured to calculate injected volumes. The growth was terminated on day 133 and plants were harvested for further analysis.

[0057] For cannabinoid analysis, the main top inflorescence from each plant was used for high-performance liquid chromatography (HPLC) sample preparation. After drying and homogenization, samples were processed using methanol solvent and cannabinoids eluded by vortexing for 2 minutes. Each sample was then filtered using 0.22 pm PTFE syringe filters, and then 5 pL of it was injected into an HPLC system (Knauer Smartline) with a CORTECS Shield RP18 column (p / n: 186008685). Mobile phase and column conditions were as per the manufacturer’s instructions. Final concentrations were calculated based on standard curves for 16 cannabinoids using a combination of two standard solutions of 9 neutral cannabinoid forms and 7 acidic forms (Restek Cannabinoids Neutrals 9 Standard Catalog No.34132, and Restek Cannabinoids Acids 7 Standard Catalog No. 34144).

[0058] Experimental results - flow rates

[0059] According to the experimental result, shown on Figure 3, the flow rates corelate with the applied pressure. Please see table 2 for comparison of flow rates averaged over different time periods in relation to applied pressure. The day of injection, when the dosing started, is counted as day 0 and the harvest occurred after 63 days of dosing.

[0060] Table 2. Applied pressure and flow rates during the dosing period. The provided times are counted from the day of injection, i.e. day 0, forward.

[0061] Maximum and minimum flow rates grouped by applied pressure or sucrose concentration at different time periods are shown in tables 3 and 4. Table 3. Maximum and minimum flow rates observed at different applied pressures. The provided times are counted from the day of injection, i.e. day 0, forward.

[0062] Table 4. Maximum and minimum flow rates observed at different sucrose concentrations. The provided times are counted from the day of injection, i.e. day 0, forward.

[0063] Furthermore, the highest flow rates were achieved in the first 24 hours of dosing, gradually decreasing and reaching essentially a constant average flow rate after approximately 4 days or more, depending on individual plants. The applied pressure had the most significant impact on the total injected volume, with higher applied pressures resulting in greater injected volumes.

[0064] As seen from tables 2-4, the flow rate can vary depending on the chosen time intervals between 0.02 mL / day to 7.74 mL / day. This flow rate is considered suitable for infusion into the cannabis plant as seen from favorable results regarding the cannabinoid yield and flower mass, as described later and shown on Figures 3 and 4.

[0065] Experimental results - cannabinoid yield analysis

[0066] The cannabinoid yield is defined as the total mass of cannabinoids obtained per plant. The cannabinoid yield analysis showed that the cannabinoid yield was significantly higher, when using the sucrose solution at appropriate flow rates or applied pressures. The cannabinoid yields also generally increased at higher sucrose concentrations, which is evident from the tests at 0.5 bar and 1 bar. This can be seen from Figure 4, showing average cannabinoid yield per plant at different dosing conditions, including applied pressure and sucrose concentration variations. On the figure, the labels P1 , P2 and P3 correspond to applied pressures of 0.5 bar, 1 .0 bar and 2 bar. The labels CO, C1 , C2 and C3 correspond to concentrations of sucrose O wt.%, 7.5 wt.%, 15 wt.%, and 30 wt.%. For example, the P1C2 labelled column corresponds to applied pressure of 0.5 bar and 7.5 wt.% of sucrose concentration The control was conducted without any injections. The columns contain the data of different cannabinoids contents, including the level of cannabidiol (CBD), cannabidiolic acid (CBDA), d9-tetrahydrocannabinol (Delta 9 THC), tetrahydrocannabinolic Acid (THCA) and others. The experiments at applied pressure 2 bar were found to provide mixed results, as some of the plants were adversely affected, as seen from the measurements of plant dry mass, flower dry mass, and a decrease in the cannabinoid yield. The measured plant dry mass, flower dry mass and cannabinoid yield at various applied pressures and sucrose concentrations is shown on Figure 5.

[0067] By comparing the flow rates and the cannabinoid yields, sucrose was found to have a crucial role in regulating secondary metabolism in plants, acting not only as an energy source but also as a signalling molecule, which has the most effect in the first few days of dosing. The infusion of the solution with saccharides into a cannabis plant was found to lower the overall photosynthetic activity, stimulate the overall growth of the plant, make the stem grow wider and the flowers bigger. The cannabinoid yield was also observed to increase substantially, depending on the conditions used.

[0068] According to the results, the plant stem infusion of the solution into cannabis plants increases the flower mass and cannabinoid yields significantly, if appropriate saccharide content and flow rates are used. However, due to the twofold effect of the sucrose, which can act as an energy source but also as a signalling molecule, a two-stage or multiple-stage infusion regime might be preferred, with varying flow rates overtime.

[0069] At an applied pressure of 0.5 bar, the cannabinoid yield per plant increased with the increase of sucrose concentrations. A similar trend was observed at applied pressure of 1 bar. At applied pressure of 2 bar, cannabinoid yields were positive or close to neutral in comparison to the control group of cannabis plants, while the flower mass and plant dry mass was adversely affected only at sucrose concentration of 15 wt.% or more.

[0070] References

[0071] 1. Zhou XM, Smith DL. A New Technique for Continous Injection Into Stems of Field-Grown Corn Plants. Crop Sci. 1996;36(2):452-6. doi:10.2135 / cropsci1996.0011183X003600020038x.

[0072] 2. Khan HA, Siddique KHM, Colmer TD. Vegetative and reproductive growth of salt-stressed chickpea are carbon-limited: sucrose infusion at the reproductive stage improves salt tolerance. J Exp Bot. 2016;68(8):2001 -11 . doi: 10.1093 / jxb / erw177.

[0073] 3. Abdin OA, Zhou X, Coulman BE, Cloutier D, Faris MA, Smith DL. Effect of sucrose supplementation by stem injection on the development of soybean plants. J Exp Bot. 1998;49(329):2013-8. doi: 10.1093 / jxb / 49.329.2013.

[0074] 4. Boyle MG, Boyer JS, Morgan PW. Stem Infusion of Maize Plants. Crop Sci. 1991 ;31 (5):1241 -5. doi: 10.2135 / cropsci1991.0011183X003100050032x.

[0075] 5. Zhou XM, Dutilleul P, MacKenzie AF, Madramootoo CA, Smith DL. Effects of Stem-injected Sucrose on Grain Production, Dry Matter Distribution, and Chlorophyll Fluorescence of Field- grown Corn Plants. J Agron Crop Sci. 1997;178(2):65-71 . doi:10.1111 / j.1439- 037X.1997.tb00352.x.

[0076] 6. Zhou XM, MacKenzie AF, Madramootoo CA, Smith DL. Effects of Stem-Injected Plant Growth Regulators, with or without Sucrose, on Grain Production, Biomass and Photosynthetic Activity of Field-Grown Corn Plants. J Agron Crop Sci. 1999; 183(2): 103-10. doi: 10.1046 / j.1439- 037x.1999.00331.x.

[0077] 7. Ma BL, Dwyer LM, Leibovitch S, Smith DL. Effect of peduncle-perfused nitrogen, sucrose, and growth regulators on barley and wheat amino acid composition. Commun Soil Sci Plant Anal. 1995;26(7-8):969-82. doi : 10.1080 / 00103629509369349.

[0078] 8. Kadowaki M, Kubota F, Saitou K. Effects of Exogenous Injection of Different Sugars on Leaf Photosynthesis, Dry Matter Production and Adenosine 5'-Diphosphate Glucose Pyrophosphorylase (AGPase) Activity in Sweet Potato, Ipomoea batatas (Lam.). J Agron Crop Sci. 2001 ;186(1):37-41. doi:10.1046 / j.1439-037x.2001 ,00451.x.

[0079] 9. Tsubone M, Kubota F, Saitou K, Kadowaki M. Enhancement of Tuberous Root Production and Adenosine 5'-Diphosphate Pyrophosphorylase (AGPase) Activity in Sweet Potato (Ipomoea batatas Lam.) by Exogenous Injection of Sucrose Solution. J Agron Crop Sci. 2000;184(3):181 - 6. doi:10.1046 / j.1439-037x.2000.00396.x.

[0080] 10. Zhang Y-L, Yang Y, Saurer M, Schaub M, Gessler A, Lehmann MM, et al. Sugar infusion into trees: A novel method to study tree carbon relations and its regulations. Front Plant Sci. 2023;14. doi:10.3389 / fpls.2023.1142595.

Claims

CLAIMS1. A small-scale delivery system of a nutrient solution (1.1) for increasing inflorescences and cannabinoid yield of cannabis plants, said delivery system comprising at least one container (1), a dosing device (2) and infusion means (3), wherein the dosing device (2) is adapted to hold at least one container (1), and the infusion means (3) is connectable to the container (1) at its first end, characterized in that• the container (1) is filled with a solution (1.1) for increasing the inflorescences and cannabinoid yield of cannabis plants and comprises a barrel (1.2) to hold the solution (1.1), a plunger (1.3) to push the solution (1.1) out and a hub (1.4) to allow the solution (1.1) to flow out of the container, wherein the solution (1 .1) is a water solution of at least one type of saccharide or combination of different types of saccharides, wherein the concentration of the solution is such as to assure osmolarity of 1 .5 Osm / L at maximum, wherein any saccharide or a combination thereof, which is soluble in water at room temperature, provides appropriate osmolarity, and can be metabolized by the cannabis plant is suitable, wherein• the dosing device (2) comprises fluid promotion means (2.1), a housing (2.2), a holder (2.3) for holding at least one container, a power supply and a controller (2.4) for controlling the flow rate, wherein the fluid promotion means (2.1) is configured to ensure fluid flow rate in the range between 0.02 to 7,74 mL / day into individual cannabis plant, wherein• the infusion means (3) of each individual container (1) is comprised of a tube (3.1) and injection means (3.2), wherein the tube (3.1) is at one end adapted to be attached to the hub of the container (1), and is at the other end attached to injection means (3.2), configured for inserting into stem of the cannabis plant, the stem diameter being in the range between 3 mm and 10 mm.

2. The delivery system according to claim 1 , characterized in that the fluid promotion means (2.1) is configured to ensure fluid flow rate in the range between 0,06 to 5,23 mL / day.

3. The delivery system according to claim 1 or 2, characterized in that the fluid promotion means (2.1) comprises a stepper motor (2.1 .1), connected to a pusher block (2.1.2) via a pushing means (2.1.3), e.g. a gear mechanism connected to a rotating rod, for enabling a specified flow rate, wherein the the stepper motor (2.1.1) is adapted to push the pusher block (2.1.2) at a preferred rate, which further pushes the plunger (1.3) of each container (1), when in operation, wherein the dosing device (2) additionally comprises a manual release button (2.5) for releasing and resetting the pusher block (2.1 .2), so it can be manually repositioned to insert full containers (1) after removing the depleted containers (1).

4. The delivery system according to any of the claims 1 to 3, wherein the holder (2.3) can hold upto nine containers (1), preferably between two and six containers (1), wherein the fluid promotion means (2.1) pushes the plungers (1.3) of all containers (1).

5. A container (1) for use within the delivery system according to any of the claims 1 to 4, characterized in that the container (1) is filled with a solution (1.1) for increasing the inflorescences and cannabinoid yield of cannabis plants and comprises a barrel (1.2) to hold the solution (1.1), a plunger (1.3) to push the solution (1.1) out and a hub (1.4) to allow the solution (1.1) to flow out of the container, wherein the solution (1.1) is a water solution of at least one type of saccharide or combination of different types of saccharides, wherein the concentration of the solution is such as to assure osmolarity of 1 .5 Osm / L at maximum, wherein any saccharide or a combination thereof, which is soluble in water at room temperature, provides appropriate osmolarity, and can be metabolized by the cannabis plant is suitable.

6. The container (1) according to claim 5, characterized in that the osmolarity of the solution (1 .1) is between 0.2 Osm / L and 0.9 Osm / L.

7. The container (1) according to claim 5 or 6, characterized in that the used saccharides are monosaccharides or disaccharides, e.g. sucrose, fructose, glucose, ribose, lactose or maltose, or complex saccharides, e.g. amylose, amylopectin, cellulose, galactogen, inulin or maltodextrin.

8. The container (1) according to any of the claims 5 to 7, characterized in that the solution (1.1) additionally contains other plant nutrients, preferably in the form of water-soluble salts, which are commonly present in fertilizers, plant growth regulators, amino acids or plant hormones.

9. A method for increasing the inflorescences and cannabinoid yield of cannabis plants, the method comprising dosing of a nutrient solution (1.1) into a stem of at least one cannabis plant using plant stem infusion through infusion means (3, over an infusion time,• wherein the nutrient solution (1.1) is a water solution of at least one type of saccharides or combination of different types of saccharides with osmolarity of 1 .5 Osm / L at maximum,• wherein the nutrient solution is infused at the predetermined flow rate in the range between 0.02 to 7,74 mL / day, or at a predetermined applied pressure in the range between 0.1 and 10 bar,• wherein the infusion is performed when a diameter of the stem of the cannabis plant is at least 3 mm,• wherein the infusion time is at least 24 h and• wherein the nutrient solution is infused with a constant flow rate regime over the infusion time, or the nutrient solution is infused with a variable flow rate regime over the infusion time.

10. Method according to claim 9, wherein the osmolarity of the solution (1.1) is between 0.2 Osm / L and 0.9 Osm / L.

11. Method according to claim 9 or 10, wherein the flow rates into individual cannabis plants is in the range between 0,06 to 5,23 mL / day, more preferably in the range between 0.2 to 2.0 mL / day.

12. Method according to claims 9 or 10, wherein the solution (1.1) is infused in two consecutive flow regimes, wherein in the first 24 hours, the solution (1.1) is infused at a higher flow rate up to 2.86 mL / day and is gradually decreased at least in the following two days to a flow rate below 1 .0 mL / day.

13. Method according to claims 9 or 10, wherein the solution (1.1) is infused in a ramp-up flow regime, starting with lower flow rate in the first 24 hours, and is gradually increased at least in the following two days up to 2 mL / day.

14. Method according to any of the claims 10 to 13, wherein the delivery system according to claim 1 is used for infusion of the nutrient solution (1.1), wherein the method involves the following steps:• the injection means (3.2) is inserted into the stem of the cannabis plant, preferably into a node at an angle of 10° to 30° according to the stem, from above, when the stem diameter is at least 3 mm;• at least one container (1) is inserted into the holder (2.3) of the dosing device (2);• the infusion means (3) is connected to at least one container (1);• the dosing device (2) pushes the solution (1.1) into the cannabis plant at a predetermined flow rate in the range between 0.02 mL / day and 7,74 mL / day or applied pressure in the range between 0.5 and 2 bar.

15. Use of the solution (1.1) for increasing the inflorescences and cannabinoid yield of cannabis plants, wherein the solution is used with the method according to any of the claims 10 to 15, wherein the solution (1.1) is a water solution of at least one type of saccharide or combination of different types of saccharides, wherein the concentration of the solution is such as to assure osmolarity of 1.5 Osm / L at maximum, wherein any saccharide or a combination thereof, which is soluble in water at room temperature, provides appropriate osmolarity, and can be metabolized by the cannabis plant is suitable.

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