WO2021162854A1

WO2021162854A1 - Nutrient composition for improving productivity and yield of hydroponically grown plants

Info

Publication number: WO2021162854A1
Application number: PCT/US2021/015173
Authority: WO
Inventors: Jonnie R. Williams
Original assignee: Mymd Pharmaceuticals, Inc.
Priority date: 2020-02-10
Filing date: 2021-01-27
Publication date: 2021-08-19

Abstract

In some aspects, a plant nutrient composition comprises water; at least one nutrient selected from the group consisting of ammonium molybdate, boric acid, calcium chelate, calcium chloride, calcium nitrate, copper chelate, copper sulfate, di-ammonium phosphate, iron sulfate, iron chelate, manganese chelate, magnesium sulfate, mono-ammonium phosphate, mono-potassium phosphate, potassium chloride, potassium sulfate, zinc chelate, zinc sulfate, and combinations thereof; and isomyosmine. The composition may contain other components, such as pH buffering agent(s). By inhibiting oxidoreductase activity, it is believed that isomyosmine may reduce oxidative stress, which in turn may promote plant health and increase productivity and yield, particularly for plants grown hydroponically.

Description

NUTRIENT COMPOSITION FOR IMPROVING PRODUCTIVITY AND YIEUD OF HYDROPONICALLY GROWN PLANTS

BACKGROUND

[01] Hydroponics, the cultivation of plants without soil, has been used to grow plants faster while reducing instances of disease. In a soilless culture, plants are cultivated using a liquid solution of water and nutrients. The pH used for the hydroponic culture is usually between 5.5 and 5.8 because overall availability of nutrients is optimized at a slightly acid pH. The availabilities of manganese (Mn), copper (Cu), zinc (Zn) and especially iron (Fe) are reduced at higher pH, and there is a small decrease in availability of phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) at lower pH.

[02] Most hydroponic reservoirs are built of plastic, but a variety of other materials have been used including concrete, glass, metal, vegetable solids, and wood. The containers should exclude light to prevent algae and fungal growth in the nutrient solution. In a static solution culture, plants are grown in containers of nutrient solution, such as glass Mason jars, pots, buckets, tubs, or tanks. The solution usually is gently aerated but may be un aerated. If un-aerated, the solution level is kept low enough that enough roots are above the solution so they get adequate oxygen. A hole usually is cut (or drilled) in the top of the reservoir for each plant. If it ajar or tub, it may be its lid, but otherwise, cardboard, foil, paper, wood or metal may be put on top. A single reservoir can be dedicated to a single plant, or to various plants. Reservoir size can be increased as plant size increases. A homemade system may be constructed from food containers or glass canning jars with aeration provided by an aquarium pump, aquarium airline tubing and aquarium valves. Clear containers are covered with aluminum foil, butcher paper, black plastic, or other material to exclude light, thus helping to eliminate the formation of algae. The nutrient solution may be changed either on a schedule, such as once per week, or when the concentration drops below a certain level as determined with an electrical conductivity meter. Whenever the solution is depleted below a certain level, either water or fresh nutrient solution is added. A float valve may be used to automatically maintain the solution level. In a raft solution culture, plants are placed in a sheet of buoyant plastic that is floated on the surface of the nutrient solution to prevent the solution level from dropping below the roots. [03] In a continuous-flow solution culture, the nutrient solution constantly flows past the roots. It is much easier to automate than a static solution culture because sampling and adjustments to the temperature and nutrient concentrations may be made in a large storage tank that has potential to serve thousands of plants. A popular variation is the nutrient film technique or NFT, whereby a very shallow stream of water containing all the dissolved nutrients required for plant growth is recirculated past the bare roots of plants in a watertight thick root mat, which develops in the bottom of the channel and has an upper surface that, although moist, is in the air. Subsequent to this, an abundant supply of oxygen is provided to the roots of the plants. A properly designed NFT system is based on selecting appropriate channel slope, flowrate, and channel length. The main advantage of the NFT system over other forms of hydroponics is that the plant roots are exposed to adequate supplies of water, oxygen, and nutrients. In all other forms of production, there is a conflict between the supply of these requirements, since excessive or deficient amounts of one results in an imbalance of one or both of the others. NFT, because of its design, provides a system where all three requirements for healthy plant growth can be met at the same time. The result of these advantages is that higher yields of high-quality produce are obtained over an extended period of cropping. A downside of NFT is that it has very little buffering against interruptions in the flow, such as power outages.

[04] Passive sub-irrigation (also referred to as passive hydroponics, semi-hydroponics, or hydroculture), is a method in which plants are grown in an inert porous medium that transports water and fertilizer to the roots by capillary action from a separate reservoir as necessary, reducing labor and providing a constant supply of water to the roots. In the simplest method, a pot sits in a shallow solution of fertilizer and water or on a capillary mat saturated with nutrient solution. The various hydroponic media available, such as expanded clay and coconut husk, contain more air space than more traditional potting mixes, delivering increased oxygen to the roots, which is important in epiphytic plants such as orchids and bromeliads, whose roots are exposed to the air in nature. Additional advantages of passive hydroponics are the reduction of root rot and the additional ambient humidity provided through evaporations.

[05] A variety of other techniques also have been used for growing plants hydroponically, including ebb and flow (flood and drain) sub-irrigation, run-to-waste systems, deep water culture technique, top-fed deep water culture, and rotary hydroponic cultivation, the details of which will be apparent to persons skilled in the art.

[06] The formulation of hydroponic solutions is an application of plant nutrition, with nutrient deficiency symptoms mirroring those found in traditional soil based agriculture. However, the underlying chemistry of hydroponic solutions can differ from soil chemistry in many significant ways. For example, unlike soil, hydroponic nutrient solutions do not have cation-exchange capacity (CEC) from clay particles or organic matter. The absence of CEC means the pH and nutrient concentrations can change much more rapidly in hydroponic setups than are possible in soil.

[07] Selective absorption of nutrients by plants often imbalances the amount of counterions in solution. This imbalance can rapidly affect solution pH and the ability of plants to absorb nutrients of similar ionic charge. For instance, nitrate anions are often consumed rapidly by plants to form proteins, leaving an excess of cations in solution. This cation imbalance may lead to deficiency symptoms in other cation based nutrients (e.g., Mg²⁺) even when an ideal quantity of those nutrients are dissolved in the solution.

[08] Depending on the pH and/or on the presence of water contaminants, nutrients such as iron can precipitate from the solution and become unavailable to plants. Routine adjustments to pH, buffering the solution, and/or the use of chelating agents is often necessary. As in conventional agriculture, nutrients should be adjusted to satisfy Liebig’s law of the minimum for each specific plant variety. Nevertheless, generally acceptable concentrations for nutrient solutions exist, with minimum and maximum concentration ranges for most plants being somewhat similar. Most nutrient solutions are mixed to have concentrations between 1,000 and 2,500 ppm. For essential nutrients, concentrations below these ranges often lead to nutrient deficiencies while exceeding these ranges can lead to nutrient toxicity. Optimum nutrition concentrations for plant varieties are found empirically by experience and/or by plant tissue tests.

[09] Organic fertilizers may be used to supplement or entirely replace the inorganic compounds used in conventional hydroponic solutions. However, using organic fertilizers introduces a number of challenges that are not easily resolved. For example, organic fertili ers are highly variable in their nutritional compositions. Even similar materials can differ significantly based on their source. For example, the quality of manure may vary widely based on an animal’s diet. Organic fertilizers are often sourced from animal byproducts, making disease transmission a concern for plants grown for human consumption or animal forage. Organic fertilizers are often particulate and may clog substrates or other growing equipment. Sieving and/or milling the organic materials to fine dusts often is necessary. Some organic materials, particularly manures and offal, can further degrade to emit foul odors.

[10] It would be desirable to develop alternative nutrient compositions for growing plants hydroponically, particularly compositions that may improve health, productivity, and/or yield of plants grown hydroponically.

SUMMARY

[11] In some aspects, a plant nutrient composition comprises water; at least one nutrient selected from the group consisting of ammonium molybdate, boric acid, calcium chelate, calcium chloride, calcium nitrate, copper chelate, copper sulfate, di-ammonium phosphate, iron sulfate, iron chelate, manganese chelate, magnesium sulfate, mono ammonium phosphate, mono-potassium phosphate, potassium chloride, potassium sulfate, zinc chelate, zinc sulfate, and combinations thereof; and isomyosmine. The composition may contain other components, such as pH buffering agent(s). By inhibiting oxidoreductase activity, it is believed that isomyosmine may reduce oxidative stress, which in turn may increase health, productivity, and/or yield, particularly for plants grown hydroponically.

[12] In another aspect, a method of growing a plant hydroponically comprises contacting the plant or a portion thereof with a plant nutrient composition comprising water; at least one nutrient selected from the group consisting of ammonium molybdate, boric acid, calcium chelate, calcium chloride, calcium nitrate, copper chelate, copper sulfate, di ammonium phosphate, iron sulfate, iron chelate, manganese chelate, magnesium sulfate, mono-ammonium phosphate, mono-potassium phosphate, potassium chloride, potassium sulfate, zinc chelate, zinc sulfate, and combinations thereof; and isomyosmine.

[13] In yet another aspect, a method of growing a plant in soil comprises contacting the plant or a portion thereof with a plant nutrient composition comprising isomyosmine. In some examples, the plant nutrient composition may be combined with water used to feed the plant. In other examples, the plant nutrient composition may be introduced into soil in the vicinity of the plant.

BRIEF DESCRIPTION OF THE DRAWINGS

[14] A more complete understanding of the present invention and certain advantages thereof may be acquired by referring to the following detailed description in consideration with the accompanying drawings, in which:

[15] FIG. 1 shows a schematic plan view of a conventional system for the hydroponic cultivation of plants;

[16] FIG. 2 shows a schematic enlarged scale view of the system of FIG. 1; and

[17] FIG. 3 shows a schematic sectional side elevation of the enlarged view of FIG. 2.

DET AIDED DESCRIPTION

[18] Aspects of the present specification disclose, in part, a plant nutrient composition (herein sometimes “composition”) comprising water, one or more nutrients selected from the group consisting of ammonium molybdate, boric acid, calcium chelate, calcium chloride, calcium nitrate, copper chelate, copper sulfate, di-ammonium phosphate, iron sulfate, iron chelate, manganese chelate, magnesium sulfate, mono-ammonium phosphate, mono-potassium phosphate, potassium chloride, potassium sulfate, zinc chelate, zinc sulfate, and combinations thereof, and isomyosmine. The composition may contain other components, such as pH buffering agent(s).

[19] As used herein, “nutrients” refers to atoms and molecules in an available form necessary for plant growth in addition to oxygen, hydrogen, and water including, but not limited to, calcium, magnesium, sodium, potassium, nitrogen, phosphorus, sulfur, chlorine, iron, manganese, copper, zinc, boron, and molybdenum. Nutrient formulations and recipes are known in the art (see, for example, Resh H. M (2001) Hydroponic Food Production, Sixth Addition, Woodbridge Press Publishing Company, Santa Barbara, Calif., USA). As used herein, “grow” and “bloom” nutrients are complete sets of nutrients for vegetative and blooming/fruiting stages of plant development. Bloom nutrients are also useful for plants growing better with more nitrogen, magnesium, sulfate, and calcium, such as herbs, particularly basil.

[20] Isomyosmine (3-(3,4-dihydro-2H-pyrrol-2-yl)-pyridine) is a nicotine-related alkaloid present in solanecea plants containing nicotine. Isomyosmine may be prepared synthetically using known techniques, and also is commercially available from several chemical suppliers. Isomyosmine has two optical isomers (+/-) owing to an asymmetric carbon atom within its pyrrole ring that joins to the pyridine ring. Unless otherwise clear from context, the term “isomyosmine,” as used herein, is inclusive of enantiomeric mixtures (+/-) including racemic mixtures, as well as isolated forms of one or the other enantiomer.

[21] Unless otherwise clear from context, “isomyosmine” as used herein refers to both salt and non-salt forms of isomyosmine. Non-limiting examples of possible salts are described in P. H. Stahl et al., Handbook of Pharmaceutical Salts: Properties, Selection and Use, Weinheim/Zurich:Wiley-VCH/VHCA, 2002, including salts of l-hydroxy-2- naphthoic acid, 2,2-dichloroacetic acid, 2-hydroxyethanesulfonic acid, 2-oxoglutaric acid, 4-acetamidobenzoic acid, 4-aminosalicylic acid, acetic acid, adipic acid, ascorbic acid (L), aspartic acid (L), benzenesulfonic acid, benzoic acid, camphoric acid (+), camphor- 10-sulfonic acid (+), capric acid (decanoic acid), caproic acid (hexanoic acid), caprylic acid (octanoic acid), carbonic acid, cinnamic acid, citric acid, cyclamic acid, dodecylsulfuric acid, ethane- 1 ,2-disulfonic acid, ethanesulfonic acid, formic acid, fumaric acid, galactaric acid, gentisic acid, glucoheptonic acid (D), gluconic acid (D), glucuronic acid (D), glutamic acid, glutaric acid, glycerophosphoric acid, glycolic acid, hippuric acid, hydrobromic acid, hydrochloric acid, isobutyric acid, lactic acid (DL), lactobionic acid, lauric acid, maleic acid, malic acid (- L), malonic acid, mandelic acid (DL), methanesulfonic acid, naphthalene- 1,5-disulfonic acid, naphthalene-2-sulfonic acid, nicotinic acid, nitric acid, oleic acid, oxalic acid, palmitic acid, pamoic acid, phosphoric acid, proprionic acid, pyroglutamic acid (- L), salicylic acid, sebacic acid, stearic acid, succinic acid, sulfuric acid, tartaric acid (+ L), thiocyanic acid, toluenesulfonic acid (p), and undecylenic acid.

[22] As an alternative to preparing isomyosmine synthetically, isomyosmine may be obtained by extraction from tobacco or other sources in which it occurs naturally. For example, a tobacco extract may be prepared from cured tobacco stems, lamina, or both. In the extraction process, cured tobacco material is extracted with a solvent, typically water, ethanol, steam, or carbon dioxide. The resulting solution contains the soluble components of the tobacco, including isomyosmine. Isomyosmine may be purified from the other components of the tobacco using suitable techniques such as liquid chromatography.

[23] While not wanting to be bound by theory, it is postulated that isomyosmine functions as an oxidoreductase inhibitor. Oxidoreductases are a class of enzymes that catalyze the transfer of electrons from reductants (electron donors) to oxidants (electron acceptors). This type of reaction is also known as an oxidoreduction reaction. The reaction generally follows the following scheme where A is the reductant and B is the oxidant:

A + B A + B

Oxidoreductases can be oxidases or dehydrogenases. Oxidases are enzymes involved when molecular oxygen acts as an acceptor of hydrogen or electrons. Dehydrogenases are enzymes that oxidize a substrate by transferring hydrogen to an acceptor that is either NAD⁺/NADP⁺ or a flavin enzyme. Other oxidoreductases include peroxidases, hydroxylases, oxygenases, and reductases. Peroxidases are localized in peroxisomes, and catalyzes the reduction of hydrogen peroxide. Hydroxylases add hydroxyl groups to its substrates. Oxygenases incorporate oxygen from molecular oxygen into organic substrates. Reductases catalyze reductions, in most cases reductases can act like an oxidases.

[24] Oxidoreductase enzymes play an important role in both aerobic and anaerobic metabolism. They can be found in glycolysis, TCA cycle, oxidative phosphorylation, and in amino acid metabolism. In glycolysis, the enzyme glyceraldehydes- 3 -phosphate dehydrogenase catalyzes the reduction of NAD⁺ to NADH. In order to maintain the re dox state of the cell, this NADH must be re-oxidized to NAD⁺, which occurs in the oxidative phosphorylation pathway. Additional NADH molecules are generated in the TCA cycle. The product of glycolysis, pyruvate enters the TCA cycle in the form of acetyl-CoA. During anaerobic glycolysis, the oxidation of NADH occurs through the reduction of pyruvate to lactate. The lactate is then oxidized to pyruvate in muscle and liver cells, and the pyruvate is further oxidized in the TCA cycle. All twenty of the amino acids, except leucine and lysine, can be degraded to TCA cycle intermediates. This allows the carbon skeletons of the amino acids to be converted into oxaloacetate and subsequently into pyruvate. The gluconeogenic pathway can then utilize the pyruvate formed.

[25] By inhibiting oxidoreductase activity, isomyosmine may reduce oxidative stress, which in turn may promote plant health and increase productivity and yield, particularly for plants grown hydroponically. An effective amount of isomyosmine may be appropriately selected depending on such factors as the variety of the plant being cultivated and the type and amount of other nutrient(s) present in the composition. By way of example, the concentration of isomyosmine may be in a range of about 0.0001 mg/mL to about 1,000 mg/mL, about 0.001 mg/mL to about 800 mg/mL, about 0.01 mg/mL to about 750 mg/mL, about 0.05 mg/mL to about 500 mg/mL, about 0.1 mg/mL to about 400 mg/mL, about 0.2 mg/mL to about 300 mg/mL, about 0.3 mg/mL to about 250 mg/mL, about 0.4 mg/mL to about 200 mg/mL, about 0.5 mg/mL to about 150 mg/mL, about 0.6 mg/mL to about 100 mg/mL, about 0.7 mg/mL to about 90 mg/mL, about 0.8 mg/mL to about 80 mg/mL, about 0.9 mg/mL to about 70 mg/mL, about 1 mg/mL to about 60 mg/mL, about 1.5 mg/mL to about 50 mg/mL, about 2 mg/mL to about 40 mg/mL, about 2.5 mg/mL to about 30 mg/mL, about 3 mg/mL to about 25 mg/mL, about 4 mg/mL to about 20 mg/mL, about 5 mg/mL to about 15 mg/mL, or about 7.5 mg/mL to about 10 mg/mL.

[26] The composition may also include a pH buffering agent. In some examples, the pH buffering agent may be selected from the group consisting of phosphate buffers, aquarium buffers, 2-[N-morpholino]ethanesulfonic acid (MES), and mixtures thereof. The pH buffering agent may comprise a sodium phosphate buffer or a potassium phosphate buffer, such as monopotassium phosphate and/or dipotassium phosphate.

[27] The composition may be supplied in any suitable form such as liquid, gel, solid powder, tablet, capsule, pellet, or granule, using methods well known in the art. A pH buffered plant nutrient composition may include sufficient nutrient and pH buffering means for growing a plant and buffering pH during growing for a time period, for example, between about 1 day and about 1 month, between about 1 week and about 3 weeks, or about 2 weeks. Usually the pH buffer maintains a water solution containing the composition within a pH range of about 3.5 to about 7.5, from about 4 to about 7, from about 5 to about 6.5, or from about 5.5 to about pH 5.8.

[28] The pH buffering agent may include a buffer selected from phosphate buffers, aquarium buffers, 2-[N-morpholino]ethanesulfonic acid (MES), or mixtures thereof. Non-limiting examples of buffers include sodium phosphate, monopotassium phosphate, and dipotassium phosphate. The concentration of the pH buffer in the nutrient solution usually ranges from about 0.1% to about 15%, from about 0.6% to about 12%, or from about 3% to about 10% based on the total weight of the nutrient solution.

[29] All waters that remain between a pH of 4 and 7 using the compositions as described herein, and do not otherwise contain any components that in the amounts used are toxic to plants, may be used. Most often, the source of water is selected from the group consisting of distilled water, deionized water, filtered or purified water, and municipal tap water.

[30] Ingredients useful for making plant nutrients are known in the art and include, but are not limited to: ammonium molybdate, boric acid, calcium chelate, calcium chloride, calcium nitrate, copper chelate, copper sulfate, di-ammonium phosphate, iron sulfate, iron chelate, manganese chelate, magnesium sulfate, mono-ammonium phosphate, mono-potassium phosphate, potassium chloride, potassium sulfate, zinc chelate, zinc sulfate, and combinations thereof.

[31] The plant nutrient composition may be packaged for a selected hydroponics system for growing a selected plant variety, whereby the amount of active ingredients is included for a selected time period when growing the selected variety in the selected hydroponics system, thereby requiring addition of only one package or one set of packages per time period. Active ingredients may include, for example, plant nutrients and pH buffering agents. For example, one package with grow nutrients suitable for seedlings of most crops or low nutrient-requiring plants grown only for vegetative tissue such as lettuce, may include plant nutrients and pH buffering agents sufficient for two weeks of growth. As another example, one set of packages for bloom nutrients suitable for herbs and flowering tomatoes, may include, in a first package, plant nutrients and pH buffering agents, and in a second package, calcium nitrate, and in a third package, magnesium sulfate, together suitable for two weeks of growth. The pH buffering agent may be combined with one or more or the plant nutrients, calcium nitrate, or magnesium sulfate.

[32] The compositions of this invention may be used for cultivating a wide variety of plants, non-limiting examples of which include flowers, lettuce, tomatoes, peppers, cucumbers, watercress, celery, strawberries, tobacco, and marijuana. Suitable systems for growing plants hydroponically are well known to persons of ordinary skill and form no part of the present invention. One such example of a suitable system is illustrated in FIGS. 1- 3 and discussed below.

[33] FIG. 1 schematically illustrates a system 10 for hydroponic cultivation of plants as disclosed in Dick U.S. Patent 6,502,350 Bl. A cultivation area of about 0.5 hectares (Ha) in size may be elongate rectangular in outline and may have a width of about 50 m and a length of about 96 m. The system 10 may include a reservoir in the form of a tank 12 having a high level inlet provided with a makeup or refill water supply line 14 provided with a gate valve 16 and a float valve 18. The tank 12 may have a low level outlet 20 feeding into a flow line 22 provided with a water circulation pump 24. Downstream of the pump 24, which is shown adjacent the outlet 20 and separated therefrom by a gate valve 26, the flow line 22 may have a further gate valve 28 downstream of the pump 24 and a filter 30 downstream of the valve 28. A branch line 32 having a gate valve 34 may branch from line 22 between the pump 24 and drain to waste; and a return- or recycle flow line 36, provided with a gate valve 38, may branch from the line 22 between the branch line 32 and the valve 28, and feed back to the tank 12 at 40. A drainage line 42 may drain into the tank 12 at a low level.

[34] The flow line 22 may feed into an elevated water feed network including, for example, seventeen water flow conduits in the form of a grid of irrigation pipes 44 spaced parallel from one another in series at a high level in a grid arrangement, having opposite ends connected respectively to an elevated manifold pipe 46 at the ends of the pipes 44 adjacent the tank 12 and to an elevated manifold pipe 48 at the ends of the pipes 44 remote from the tank 12. The manifold pipe 48 is optional and may be omitted, the pipes 44 in which case being blind at their ends remote from the pipe 46. Each pipe 44 may carry a series of sixty-two water flow conduits in the form of water feed manifolds, suspended and downwardly depending therefrom, having closed lower ends resting on the ground, the water feed manifolds not being shown in FIG. 1 but being as described below with reference to FIGS. 2 and 3.

[35] The drainage line 42 may drain into the tank 12 from a water drainage network including a plurality of water drainage conduits in the form of a grid of seventeen low level drainage pipes 50 resting on the ground, spaced apart from one another in series in a grid arrangement corresponding to that of the pipes 44. The pipes 50 may extend from a manifold pipe 52, below the manifold pipe 46 and at the ends of the pipes 50 adjacent the tank 12, to a manifold pipe 54 below the manifold pipe 48 and at the ends of the pipes 50 remote from the tank 12. Similarly to the manifold pipe 48, the manifold pipe 54 is optional and may be omitted, in which case the ends of the pipes 50 remote from the manifold pipe 52 may be blind ends. The pipes 50, 52 and 54 rest on the ground. The pipes 50 each may carry a series of sixty-two plant support stmctures in the form of elongate plant support columns comprising rooting compartments and projecting upwardly from the pipes 50. The columns are not shown in FIG. 1 but are described hereunder with reference to FIGS. 2 and 3 and the columns of each pipe 50 are spaced in series along the length of the pipe 50. Each pipe 50 may be below, and corresponds with, one of the pipes 44; and each column corresponds with and extends alongside one of the feed manifolds, being in flow communication therewith, as described below with reference to FIGS. 1 and 2. The water drainage conduits of the water drainage network may lead from the rooting compartments of the columns to the reservoir tank 12.

[36] The horizontal spacing between adjacent parallel pipes 44 may be the same as the horizontal spacing between adjacent parallel pipes 50, such as 6 m. The spacing between adjacent feed manifolds may be the same as the spacing between adjacent plant support columns, such as 800 mm. The feed manifolds at the opposite ends of each series thereof may be spaced about 200 mm from the ends of the associated pipe 44 respectively, e.g., from the pipes 46 and 48. Similarly, the columns at the opposite ends of each series thereof may be spaced about 200 mm from the ends of the associated pipe 50 respectively, e.g., about 200 mm from the pipes 52 and 54. The pipes 44 are of 25 mm outer diameter and the pipes 46 and 48 are of 40 mm outer diameter, being polyethylene pipes with a wall thickness sufficient to contain an internal pressure of at least about 6 atmospheres, being pipes with a wall thickness of about 1.5 mm or more. The pipes 50, 52 and 54 likewise may be constructed of polyethylene, and all may be about 50 mm outer diameter and able to contain at least about 6 atmospheres pressure and being of a 1.5 mm wall thickness or more. Alternatively, the pipes 50, 52 and 54 may be of polyvinyl chloride (PVC), e.g., of about 63 mm outer diameter; and the pipes 44, 46 and 48 may also be of PVC.

[37] The pipes 50, 52, and 54 may rest on bare soil, with the system 10 uncovered and open to the elements and ambient atmosphere. Alternatively, the pipes 50, 52 and 54 may rest on a layer of sand or gravel, or on a concrete or cement apron and may be covered by one or more translucent or transparent plastics plant growth tunnels to protect the plants from the elements. The floor of each tunnel may be covered, for example, by a white, light-reflective sheet material, for reflecting light upwardly onto plants being cultivated in the tunnel.

[38] Each pipe 44 may be approximately directly above the associated pipe 50, and the manifold pipes 46 and 48 may be approximately directly above the manifold pipes 52 and 54 respectively. For ease of illustration, the upper pipes 44, 46 and 48 are shown in FIG. 1 to be somewhat offset from the corresponding lower pipes 50, 52 and 54. The grid of pipes 44 is a high level grid at or slightly above the elevation or level of the tops or upper extremities of the plant support columns, the grid of pipes 50 being a low level grid at or slightly below the elevation or level of the bottoms or lower extremities of the plant support columns.

[39] The grid of pipes 44, 46 and 48 may be positioned at a high level as shown in FIG. 1 or, alternatively, at a lower level, such as at ground level, e.g., approximately at or slightly below the lower extremities of the support columns, with the pipes 44, 46 and 48 being located alongside the pipes 50, 52 and 54 respectively. An advantage of having the grid of pipes 44, 46 and 48 resting on the ground, is that a less robust trellis structure may be needed to support the plant support columns and the associated water feed manifolds 56 and 58, respectively, in FIGS. 2 and 3. In this case, the water feed manifolds 58 may project upwardly from the pipes 44, alongside the columns 56, instead of depending downwardly as shown in FIG. 3.

[40] FIGS. 2 and 3 show details of the system 10 not illustrated in FIG. 1, primarily the plant support columns and the water feed manifolds. Part of one of the drainage pipes 50 is shown, supporting two vertically extending plant support columns, each generally designated 56 and each associated with one of the water feed manifolds, generally designated 58.

[41] The centers of the columns 56 may be spaced apart by a spacing along the length of the drainage pipe 50, e.g., by a spacing of about 800 mm. Each column may be supported in the central leg of a T-piece 60, the T-piece 60 being inserted into and forming part of the pipe 50. There may be sixty-two T-pieces in each pipe 50 and the pipe 50 being formed from sixty-three portions 62. Each pipe portion 62 may be about 0.75 m in length and have its ends connected to the T-pieces 60 received spigot/socket fashion, as spigots in sockets constituted by the arms of the associated T-pieces, being glued in position. The T-pieces may be of similar polyethylene or PVC construction, diameter and wall thickness, to the pipes 50.

[42] Each column 56 may be formed, essentially, of a water drainage manifold in the form of a PVC or polyethylene pipe 64, and of a sleeve 66 of 200 mm diameter, 100 pm thickness flexible water-impervious polyethylene sheet material containing plant rooting medium 68 of compacted particulate organic material such as peat, although synthetic particulate material may be used instead. The PVC sheet material may have a white surface and a black surface. Thus, the sleeve 66 may be formed to have a white outer surface to reflect incidental ambient light on to plant foliage, and a black inner surface to discourage growth of algae thereon, inside the sleeve 66. Each column 56 may be divided by a series of waist-like constrictions 70 spaced along its length, into a series of rooting compartments 72 extending along its length. Each constriction 70 may be formed by a PVC or like plastics cable tie 74 of the type usually used for tying together electrical cables. Each tie 74 may be tied under tension circumferentially around the sleeve 66 to form one of the constrictions 70. Each tie 74 may be tied tightly enough to form a constriction 70 which holds the rooting medium 68 in place in the compartment 72 above that tie 74, and tightly enough to support that compartment 72 on a shoulder 76 on the pipe 64. The pipe 64 may extend along the interiors of the series of rooting compartments 72 of the associated column 56, inside the sleeve 66.

[43] Each pipe 64 may be a water drainage conduit forming part of the water drainage network and is provided, standing proud of its outer surface, with a series of protrusions spaced along its length in the form of circumferentially extending radially outwardly projecting ribs or shoulders 76. The pipe 64 may be of about 50 mm outer diameter and about 1.5 mm wall thickness. The shoulders 76 may be formed integrally on the outer surface of the pipe 64 by injection molding and may be about 10 mm wide, in the radial direction and about 4 mm in the longitudinal (in-use vertical) direction. Adjacent shoulders 76 may be spaced apart from each other by spacings of about 200 mm, except for the uppermost pair and the lowermost pair of shoulders 76, which shoulders 76 may be spaced apart by about 160 mm. The tie 74 of each constriction 70 may be tied sufficiently tightly for that constriction 70 to be securely supported on an associated one of the shoulders 76. The uppermost and lowermost compartments 72 may be about 160 mm high, the remainder being about 200 mm high, each 200 mm high compartment being about 5 L in volume.

[44] A plurality of PVC or polyethylene pipe lengths may fit together end-to-end in a spigot/socket engagement to form the pipe 64. Each pipe length may be about 50 mm outer diameter, about 240 mm overall length (e.g., about 190 mm effective length when fitted together) and about 2 mm wall thickness, with each pipe length carrying one of the 10 mm wide and 4 mm thick shoulders described above, integrally molded therewith adjacent one end thereof, and having two appropriately located rings of drainage openings (see 84 as described below with reference to FIG. 3) respectively adjacent opposite ends thereof. The lengths may be releasably locked together by means of a locking mechanism forming part of each pipe length. In use, a plurality of lengths may be locked together, end-to-end, in spigot/socket engagement. The lengths each may have a spigot portion at one end and a socket portion at the other, in which the drainage openings are provided, the shoulder being at the end of the length provided with the spigot portion, and, at each spigot/socket connection, the drainage openings of the spigot portion registering with the drainage openings of the associated socket portion. There may be one pipe length associated with each compartment, e.g., ten pipe lengths for ten compartments, all the compartments thus typically being the same height and size.

[45] The upper end of each pipe 64 may be closed off by a plastics cap 78, e.g., adhesively secured thereto; and the lower end of each pipe may have a releasable (unglued) friction fit in the central leg of the associated T-piece, with the leg of the T-piece being designated 80 and its arms being designated 82. Two longitudinally spaced rings of circumferentially spaced drainage openings 84 may be provided, adjacent and closely spaced above each shoulder 76, except for the uppermost shoulder, the lower ring being 20 mm above the adjacent shoulder 76 and the upper ring being 20 mm above the lower ring and 40 mm above said shoulder. The openings 84 may be at a level below the midpoint, in the vertical direction, of the associated compartment 72 and lead into the interior of the pipe 64.

[46] Each feed manifold 58 may be in the form of a 15 mm outside diameter polyethylene pipe having an upper end mechanically and releasably connected to an opening therefor in the associated pipe 44 and depend downwardly from the pipe 44. The manifold 58 may have a closed lower end closed by a cap 86 which rests on the ground 88. The columns 56 and the associated manifolds 58 and grid of pipes 44, 46 and 48 may be supported by a suitable trellis structure (not illustrated), e.g., made up of wire and support posts. A water flow conduit formed by an irrigation connection including an irrigation nozzle in the form of a tube 90 may project into each compartment 72 of each column 56, from the associated manifold 58. Each tube 90 may have an upstream end provided with an external circumferential rib or shoulder (not illustrated) received and mechanically secured and held in an opening therefor in the wall of the pipe 58, and a downstream end projecting into an associated one of the rooting compartments 72, through an opening or slit therefor, formed in the sleeve 66. The downstream end of the tube 90 may be held fictionally in position by the rooting medium 68, into which it protrudes at a high level, above the midpoint, in the vertical direction, of the associated rooting compartment 72, the rings of openings 84 being below that midpoint. Each tube 90 may be connected to the pipe 58 by a self-regulating flow regulator, in the form of a drip irrigation fitting or nozzle of conventional construction (not illustrated).

[47] During normal use of the system 10, irrigation water having dissolved therein the plant nutrient components as described herein may be intermittently pumped by the pump 24 from the tank 12, with the valves 16, 26, 28 and 38 open, and the valve 34 closed. The pump 24 may pump the composition through the tank outlet 20 and along lines 22 and 36, the valves 28 and 38 having their apertures adjusted so that about two-thirds of the output of the pump 24 passes along the line 22 from the valve 28 to the filter 30, the remaining third of this output may be recycled along line 36 to re-enter the tank 12 at 40. [48] Water flowing along line 22 downstream of the filter 30 may enter manifold pipe 46 and flow in parallel along irrigation pipes 44 to manifold pipe 48. From each pipe 44 water may flow down the associated water feed manifolds 58 to the associated tubes 90, along which tubes 90 the water flows in parallel to the associated rooting compartments 72 where it enters the rooting medium 68 from the downstream ends of the tubes 90. Water entering the compartments 72 may saturate the rooting medium 68 therein, the water draining downwardly under gravity through the rooting medium 68 until it reaches the rings of drainage openings 84, through which it drains into the associated drainage manifold 64. Thus, water may drain downwardly under gravity in the manifolds 64 into the drainage pipes 50. From the pipes 50, the water may drain into the manifold pipe 52, and then into the drainage line 42 along which it drains into the tank 12. Thus, in essence, the pump 24 may circulate water along a water circulation network constituted by the reservoir or tank 12, by the plant support structures or columns 56, by the water feed network of pipes 22, 44, 46 and 48 and manifolds 58 and tubes 90, and by the water drainage network of pipes 42, 50, 52, 54 and 64.

[49] During normal use of the installation 10, a plurality of plants may be rooted in the rooting medium 68 of each rooting compartment 72. The stems of the plants may protrude out of the rooting compartment 72 via a plurality of openings in the form of holes or slits (one of which is shown at 92 in FIG. 2) through the wall of the compartment 72 constituted by the material of the sleeve 66. These holes or slits may be equally circumferentially spaced from one another in series, e.g., at a spacing of 90° apart when seen from above, around each compartment 72, being located at a level above the midpoint of the compartment 72, to resist loss of water by unintended drainage of water outwardly through the holes or slits to the exterior of the sleeve 66, there being a total of four holes or slits in each compartment, each about 25 mm in diameter or length respectively, for rooting four plants in each compartment.

[50] From time to time, as and when necessary, the pumping may be interrupted, for example by an automatic timer switch, to allow the rooting medium to drain and dry out as fully as possible, and to become aerated/oxygenated, before pumping is resumed. As a consequence of water transpiration by the plants, water may be conducted by the plants from the rooting medium 68 into the ambient atmosphere outside the sleeve 66, where it is lost by evaporation. Accordingly, automatically and from time to time as required, water in tank 12 may be replenished via supply line 14 and float valve 18, the gate valve 16 remaining open during normal operation. Furthermore, as dissolved nutrients in the water are consumed by the plants, their concentrations may be measured in the water in the tank 12, the nutrients being replenished by addition thereof to the water in the tank as necessary.

[51] Heating and cooling of plants may be effected, for example, by circulating warm or cold air along the circuit of the installation, along the interiors of the columns 56. This not only aerates and oxygenates the rooting medium 68, but also remove gaseous respiration by-products therefrom. If desired, carbon dioxide may be circulated through the rooting compartments 72, to regulate or stimulate plant growth.

[52] Gases may be injected into the compartments 72 in the reverse direction to irrigation water, blown up the pipes 64 of the columns 56 and through the holes 84 into the compartments 72, and out of the slits into the ambient air. Temperatures in the compartments may be regulated, as desired, both to promote growth and to promote flowering and fruiting, e.g., by maintaining temperatures of about 10-18°C. Heating and/or cooling may be of the roots of the plants in the compartments 72 and/or of the plant foliage outside the compartments 72. If desired, an electrical resistance heating cable may be wrapped around the tubes 64 in the compartments 72, for electrical resistance heating of the rooting medium 68.

[53] Irrigation may be carried out at a rate such that unacceptable build-up of salts in the rooting medium 68 is resisted, without any substantial water loss. Purified water, for example, may be used for this purpose.

[54] While particular embodiments have been described and illustrated, it should be understood that the invention is not limited thereto since modifications may be made by persons skilled in the art. The present application contemplates any and all modifications that fall within the spirit and scope of the underlying invention disclosed and claimed herein.

Claims

WHAT IS CLAIMED IS:

1. A plant nutrient composition comprising: water; at least one plant nutrient selected from the group consisting of ammonium molybdate, boric acid, calcium chelate, calcium chloride, calcium nitrate, copper chelate, copper sulfate, di-ammonium phosphate, iron sulfate, iron chelate, manganese chelate, magnesium sulfate, mono-ammonium phosphate, mono-potassium phosphate, potassium chloride, potassium sulfate, zinc chelate, zinc sulfate, and combinations thereof; and isomyosmine.

2. The plant nutrient composition of claim 1 further comprising at least one pH buffering agent.

3. The plant nutrient composition of claim 2 wherein the pH buffering agent is selected from the group consisting of 2-[N-morpholino]ethanesulfonic acid (MES), sodium phosphate, potassium phosphate, monopotassium phosphate, dipotassium phosphate, and combinations thereof.

4. The plant nutrient composition of claim 1 wherein a concentration of isomyosmine is about 0.0001 mg/mL to about 1,000 mg/mL.

5. The plant nutrient composition of claim 1 wherein a concentration of isomyosmine is about 0.001 mg/mL to about 800 mg/mL.

6. The plant nutrient composition of claim 1 wherein a concentration of isomyosmine is about 0.01 mg/mL to about 750 mg/mL.

7. The plant nutrient composition of claim 1 wherein a concentration of isomyosmine is about 0.05 mg/mL to about 500 mg/mL.

8. The plant nutrient composition of claim 1 wherein a concentration of isomyosmine is about 0.1 mg/mL to about 400 mg/mL.

9. The plant nutrient composition of claim 1 wherein a concentration of isomyosmine is about 0.2 mg/mL to about 300 mg/mL.

10. The plant nutrient composition of claim 1 wherein a concentration of isomyosmine is about 0.3 mg/mL to about 250 mg/mL.

11. The plant nutrient composition of claim 1 wherein a concentration of isomyosmine is about 0.4 mg/mL to about 200 mg/mL.

12. The plant nutrient composition of claim 1 wherein a concentration of isomyosmine is about 0.5 mg/mL to about 50 mg/mL.

13. A method of growing a plant hydroponically comprising contacting the plant or a portion thereof with the plant nutrient composition of claim 1.

14. A method of growing a plant in soil comprising contacting the plant or a portion thereof with the plant nutrient composition of claim 1.

15. A method of growing a plant in soil comprising contacting the plant or a portion thereof with a plant nutrient composition comprising isomyosmine.

16. The method of claim 15, wherein the plant nutrient composition is introduced into soil in the vicinity of the plant.

17. The method of claim 15, wherein the plant nutrient composition further comprises water and the plant nutrient composition is contacted with the plant or portion thereof as feed water for the plant.

18. The method of claim 17, wherein a concentration of isomyosmine is about 0.01 mg/mL to about 750 mg/mL.

19. The method of claim 17, wherein a concentration of isomyosmine is about 0.05 mg/mL to about 500 mg/mL.

20. The method of claim 17, wherein a concentration of isomyosmine is about 0.5 mg/mL to about 50 mg/mL.