AU2004205304B2 - Improvements in and relating to humic compositions - Google Patents

Description

P/00/011 Regulation 3.2

AUSTRALIA

PATENTS ACT 1990 Original Complete Specification Standard Patent Invention Title: IMPROVEMENTS IN AND RELATING TO HUMIC COMPOSTIONS The following statement is a full description of this invention, including the best method of performing known to me:

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WO 00134413 PCT/NZ99D0208 IMPROVEMENTS IN AND RELATING TO HUMIC COMPOSITIONS TECHNICAL FIELD The present invention is directed primarily to agriculture and horticulture.

It is directed primarily to compositions facilitating the presence of humus in substrates such as soil.

BACKGROUND ART Humus is an important component of productive soils. Soils throughout the world lose fertility by the humus being destroyed or eroded. This loss may be caused by many reasons, including over cultivation where the loss occurs by removal of crops year after year without replacement of organic material such as humus. Farmers often force crop yields by the over use of nitrogenous fertiliser or use fertilising agents which upset nature's recycling of materials by bacterial and fumgal action, and soil based animal life such as earthworms. Quite often these useful organisms are destroyed in large numbers, which significantly affects soil characteristics.

Other factors include the removal of trees in favour of cropping. Weather conditions which then remove top soil through water and wind erosion remove significant quantities of humus which, if left unattended over a period of time, produces non-productive land or deserts.

It is well known that the formation of humus by nature often takes a considerable period of time. Accordingly nature often struggles to keep pace with humus loss caused by man's interaction with the environment.

This is one problem which the present invention seeks to address.

Humus is usually formed in nature by the decomposition of plant and 1 WO 00134413 WO 0034413PCT/N Z99/00208 animal material in the soil by various organisms and micro-organisms present. The general analysis of humus shows a typical composition of around 70 90% water, 2 5% of minerals, and the remainder being organic materials. A good proportion of humus is cellulose, protein, amino acids, polypeptides, enzymes, nucleic acids, as well as other forms of carbohydrates, fats, oils, and minerals.

Apart from its importance as a soil nutrient, humus also provides structural texture to soil, allows water to be held, nutriments to be stored without leaching, and is an ideal medium to support bacteria, ftungi, and other organisms important to the soil.

Successfully re-introducing humus into the soil or other substrates is not easy. Agricultural methods often rely on the return of organic matter, such as composts, rendered animal materials, animal manures, etc. However, returning organic material to the soil is not always practicable for some environments, and when applied still only represents a pre-cursor to the formation of humus in the soil i.e. in most cases the organic materials provided represent little more than an ingredient for humus formation.

Nature and time must then take over to produce the humus which is desired for conditioning the soil. It would be of significant use and value if a method existed for accelerating or otherwise promoting the formation of humus in soils and other substrates.

It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.

Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

WO 00/34413 PCT/NZ99/00208 DISCLOSURE OF INVENTION According to one aspect of the present invention there is provided a humic composition which includes a clathratic substantially water soluble cellulose component, or any synthetic or natural polymers and which is substantially free of polyvalent cations, the composition characterised such that when dissolved in water it remains substantially free of any gelforming but when polyvalent cations are introduced it begins thickening.

For example, sodium salts of carboxymethyl cellalose, when dissolved in water, becomes viscous without the presence of polyvalent cations.

Further, the gel is formed with polyvalent cations if added.

According to another aspect of the present invention there is provided a humic composition, substantially as described above, which includes, as a clathratic substantially water soluble cellulose product, at least one carboxyalkyl cellulose compound or a salt thereof.

According to another aspect of the present invention there is provided a humic composition, substantially as described above, wherein said clathratic substantial water soluble cellulose product further includes a combination of one or more polymeric soil conditioners.

For example, the combination of one or more polymeric soil conditioners may be natural polyuronic acids, mannuronic acid salts, polysacharides or insoluble linear hydrolysed polyacrylonitrile.

According to another aspect of the present invention there is provided a humic composition, substantially as described above, in which a carboxyalkyl cellulose is produced by the reaction of cellulose with the halogenated alkali salt of a carboxy acid and a monobasic alkali.

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WO 00/3 4413 PCTINZ99100208 According to another aspect of the present invention there is provided a humic composition, substantially as described above, which includes one or more soluble components selected from the following list, providing they are substantially free of polyvalent cations promoting gel formation: carbohydrates, humic acids, soluble extracts derived from plant matter, soluble extracts derived from animal matter, soluble plant nutrients, enzymes and in particular enzymes associated with soil activity or degradation of soil material, proteins and proteinaceous material, amino acids and amino acid salts and derivatives, peptides and polypeptides, nucleic acids and nucleoprotamines, non-phytotoxic amines and amides, vitamins and plant essential elements and minerals.

According to another aspect of the present invention there is provided a humic composition, substantially as described above, which includes one or more insoluble components in a substantially fine form.

According to another aspect of the present invention there is provided a humic composition, substantially as described above, in which insoluble components are sufficiently fine to form substantially a suspension when the composition is dispersed in a carrner.

According to another aspect of the present invention there Jig provided a huinic composition, substantially as described above, which includes insoluble components from the following list, providing they are substantially free of polyvalent cations promoting gel formation: plant derived material, animal derived material, material derived from the decay or partial decay of substantially organic matter, carbohydrates, plant nutrients, enzymes and in particular enzymes associated with soil activity or degradation of soil material, proteins and proteinaceous material, amino acids and amino acid salts and derivatives, peptides and polypeptides, 4 WO 00134413 WO 0034413PCTINZ99/O0208 nucleic acids and nucleoprotamines, non-phytotoxic amines. and amides, and plant essential elements and minerals.

According to another aspect of the present invention there is provided a humic composition, substantially as described above, which includes components from the following list: biological organisms, bacteria, algae 1 protozoa, fauna, and f'ungal material including reproductive material, micro-organisms including reproductive material therefor, and especially of fungi or micro-organisms exhibiting soil activity or activity towards the degradation of soil material.

According to another aspect of the present invention there is provided a humic composition, substantially as described above, which includes polyvalent -cations in a- chelated or complexed -form such that they are substantially unable to promote gel formation in the composition.

According to another aspect of the present invention there is provided a humic composition, substantially as described above, which is farther characterised that when applied to a substrate, reacts with polyvalent cations present in the substrate to begin thickening.

According to another aspect of the present invention there is provided a huinic composition, substantially as described above, whose action when applied to soil is to stabilise applied components to the substrate in a manner resisting their leaching.

According to another aspect of the present invention there is provided a humic composition, substantially as described above, wherein said action, when applied to soil, has the further affect of preventing interaction with polyvalent cations in the soil with the complexes or chelates made from polyvalent cations that have had the positive charges reduced to zero.

rrtrr. rz~ WO 00/34413 PCTINZ99/00208 According to another aspect of the present invention there is provided a huinic composition, substantially as described above, which increases humus forming reactions within the substrate.

According to another aspect of the present invention there is provided a huinic composition, substantially as described above, which includes an amnide and a hydrolysing enzyme such that, once applied to a substrate or in favourable conditions, react to release ammonia.

According to another aspect of the present invention there is provided a humic composition, substantially as described above, which includes an ester and a carboxylesterase, the combination characterised by being of a type which releases urea after application to a substrate or in favourable conditions.

According to another aspect of the present invention there is provided a humic composition, substantially as described above, which includes a substituted amine derivative of urea and the enzyme carboxylesterase, the combination being of the type such as to produce urea and an amine after application to a substrate or in favourable conditions..

According to another aspect of the present invention there is provided a huinic composition, substantially as described above, which includes an organic phosphate ester and a phosphorylase enzyme, the combination being of the type such as to produce a soluble phosphate or phosphorus acid after application to a substrate or in favourable conditions.

According to another aspect of the present invention there is provided a huinic composition, substantially as described above, including an enzyme which also includes a chelated form or copper and/or iron.

6 *nrfl~ WO 001344 13 PCT1NZ99100208 According to another aspect of the present invention there is provided a humic composition, substantially as described above, which is in a substantially dry form for subsequent dilution in a carrier.

According to a fturther aspect of the present invention there is provided a huinic composition, substantially as described above, when applied to soil or another substrate.

According to a further aspect of the present invention there is provided a hamic composition, substantially as described above, when applied to soil or another substrate in conjunction with the application of one or more other compositions which contain substances promoting thickening of the humic composition.

In the broadest sense the present invention can be defined as including compositions which in turn include a clathratic substantially water soluble cellulose component. More specifically, this water soluble cellulose product is characterised such that the composition, when dissolved in water, remains substantially free of any gel forming reactions. However, under certain ci.rcunxstances,- such as the presence of polyvalent cations, it begins to thicken and form a gel.

In practice, the compositions may eist in a dry or wet form. Whatever form the compositions may be stored in their bulk state, they would typically be introduced to a carrier before application to soil or other substrates acting as growth media. Usually this catrer will be water, as for most agricultural compositions and chemicals. In this diluted state the composition will also be substantially free of any thickening reactions, though it is envisaged that over time certain thickening reactions may occur. However, in the presence of polyvalent cations, thickening will WO 00/34413 WO 0034413PCT/NZ99/00208 commence. Typically this will transform the diluted composition into a gel like consistency though this will of course depend upon the dilution ratio.

In practice, such polyvalent cations are present in most soils and substrates representing growth media. Accordingly, a relatively stable composition (with respect to thickening) can be prepared and applied to the various substrates. Once polyvalent cations within the substrate are encountered, thickening reactions will commence which will tend to form areas of gel which trap localised components. These localised components may be substances and components already present in the substrate, though may also include other components introduced along with, or in coapplication with, the humic composition being described. This can help resist leaching of the various products from the substrate, This assists in the formation of humus. For instance, by gelling and locking nutrients and various components into a particular area, it can help to establish a localised environment amenable to many soil and substrate related reactions and activities. These include processes favouaring the formation of humus.

As can be appreciated, the production of humus can be further accelerated by the introduction of other components, with the basic humic composition, which are known to promote the formation of humus, either directly or indirectly. Some of these components will be discussed later within this specification.

Returning to the broadest aspect of the present invention, a preferred clathratic substantially water soluble cellulose product comprises a water soluble carboxyalkyl cellulose for example sodium methyl carboxycellulose. Typically, these types of products can be prepared WO 00134413 PCTNZ99OO2OS by the reaction of cellulose with a monobasic alkali, such as ammonium or alkali metal alkalis, in the presence of a halogenated alkali salt of a carboxyacid for example sodium chioroacetic acid.

For instance, cellulose consists of glucose molecules linked together by beta linkage through the 1,4 position into very long chains having typical molecular weights of 100,000 500,000 this corresponds to typically 600 3,000 units of glucose per molecule. If we represent cellulose by the general formula R-OH, for simplicity, then the preferred reaction becomes: R-OH CICH 2 COONa NaOH R-O-CH 2 000Na NaCl H 2 0 Typically the product is soluble in both hot and cold water and is crystallised out and dried.

Humus in the soil comprises a significant proportion of organic material if the high water content is disregarded. Of this organic material, a significant proportion comprises cellulose, typically from decaying plant and other organic matter. The present invention helps to increase level's of humus by introducing further cellulose into the substrate.

Combinations with cellulose with synthetic polymers will enhance the thickening and gel like formation which has calthratic properties.

The mere addition of cellulose will also eventually increase humus levels though its generally insoluble nature means that it can be some time before it enters successfully into the soil processes which ultimately yield humus. By providing cellulose in a more reactive and soluble form, various processes can be initiated and completed much more quickly and thus nature is given something of a head start or helping hand. Further, the availability of more readily accessible forms of cellulose can increase

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WO 00/34413 PCT/NZ99/00208 substrate populations of beneficial organisms involved in the production of humus and conditioning of soil. This too can augment existing processes dealing with cellulose and organic matter already in the soil. Accordingly, use of the present invention can in favourable circumstances provide more advantage than the mere introduction of further cellulose material into the soil for humus production.

While the broadest aspect of the present invention can provide benefit for many substrates, it is also considered that beneficial effects can be further enhanced and augmented by the inclusion of additional materials with compositions according to the present invention. Typically these include materials which can provide further raw materials for humus production, and in combination with the clathratic soluble cellulose, become entrained in various pockets of thickened material within the substrate to produce a localised concentration favouring certain beneficial processes.

In addition, it has also been considered that introducing further bulk organic material can be of further benefit by increasing the quantity of cellulose and useful organic materials in the soil. Any increase in local populations of active and beneficial organisms due to other effects of the present invention will quickly expand to encompass other organic material also introduced, and to further accelerate and accentuate the total amount of humus in the substrate. In addition, use can be made of many other components which may undergo further reactions (see later) to release further substances within the substrate.

By way of example of the preceding, additional components which may be introduced into various compositions include organic materials useful for humus production and/or supporting or establishing populations of beneficial micro-organisms. These components may include (though WO 00/34413 PCTINZ99/00208 preferably will be substantially free of polyvalent cations promoting gel formation) the following: carbohydrates, soluble extracts derived from plant matter, soluble extracts derived from animal matter, protein and proteinaceous material, amino acids and amino acid salts and derivatives, peptides and polypeptides, nucleic acids and nucleoprotamines, various non.-phytotoxic amines and amides, vitamins etc. The foregoing may be present in a soluble form. However, these and other components (including marine, plant, and animal derived matter) may also be present in a substantially insoluble form. When insoluble components are added, it is desirable that either they are of a form so that they can be readily dispersed in a liquid composition, or in effect act as a carrier for the other components.

In the former case, easy dispersion typically means a situation where the components can be substantially homogenously dispersed throughout a liquid composition and will remain relatively evenly dispersed until application has been made. Ideally suspensions of the insoluble components are preferred.

In the latter situation, we have bulk solid material acting as a carrier. In this case, the base composition may be applied substantially uniformly throughout the solid material. It is possible that it may exist as substantially a surface coating. An example, would be medium to dry shredded plant material (for instance of the consistency of many commercial potting or compost mixes) through which has been distributed other components including the clathratic soluble cellulose.

As can be appreciated there are a number of different ways in which the present invention can be put into effect. However, for simplicity, the remainder of the description will refer (unless otherwise stated) to WO 00/34413 WO 00/44 13PCT/NZ99/00208 embodiments intended for the formation of liquid compositions for application to the substrate.

The problem when powdered soluble components along with the monovalent cation salt of carboxymethy cellulose is in high concentration with the other ingredients is that it clumps together in big lumps. By making pills the size of confectionery or "hundreds and thousands" it dissolves quickly without forming lumps.

Other components which may be included are fungi, micro-organisms, and reproductive material for either or both. Preferably these will represent fungi and organisms which are beneficial to the soil and preferably which are shown or known to be active in soil processes involving the formation of humus or in processes favourable (either directly or indirectly) to same.

Such organisms and fungi are well known and will not be recited herein.

Further components which may be considered for inclusion within the present invention include plant available nutrients, both soluble and insoluble, including either or both plant essential elements and minerals.

This includes the main NPKS elements. Once again, as for other components, care should be taken to exclude any polyvalent cations which promote a thickening reaction in the clathratic cellulose component.

Examples of some compounds which may be includes comprise: salts of Na t IC', and NH 4 4 e.g. potassium dihydrogen phosphate, sodium nitrate, ammoniumn sulphate, potassium amino acetate, dipotassiurn hydrogen phosphate, and urea etc.

A number of plant essential nutrients comprise metals having polyvalent cations. These may be included in various compositions, providing they are not in a free state where they are able to promote thickening of the WO 00/34413 WO 0034413PCT/NZ99/O0208 clathratic cellulose component. For inclusion into preferred embodiments of the present invention, it is desirable that elements having polyvalent cations are chelated or otherwise in a stable complexed form where they are substantially inactivated with respect to thickening of the clathratic components.

Elements having polyvalent ions which may be incorporated in various composition include: boron, magnesium, calcium, cobalt, copper, iron, zinc, manganese, molybdenum, selenium, chromium etc. This list is not intended to be exhaustive.

It is also noted that binding the polyvalent cations, when present, in stable complexes helps also to avoid other undesirable interactions when in solution or suspended. It is noted that unwanted reactions still have the potential to occur, though it is considered that it would be within the ability of a skilled addressee of the art to perform minor experimentation to arrive at many useful combinations of various chelated compounds for use in various embodiments of the present invention.

Other components which may be used in various components of the present invention include various enzymes. A number of enzymes are known to assist in the degradation and decomposition of various types of material and thus may be considered for inclusion within the present invention.

Many enzymic reactions produce heat, useful in promoting early germination, plant growth and root activity.

In other instances enzymes may be included because of a reaction with other components to yield materials which are of use in soil processes.

For instance, there may be included an amide and a hydrolysing enzyme, the combination characterised such that once applied to a substrate or WO 00134413 WO 0034413PCTINZ99/O0208 placed in favourable conditions, they react so as to release ammonia. The role and usefulness of ammonia, particularly as a source of nitrogen, is well known in soil and plant processes.

Another example would be a combination of a substituted amine derivative of urea with a carboxylesterase enzyme, with the combination characterised so as to produce urea and an amine after application to a substrate or when placed in otherwise favourable conditions. Again ureas.

and amines can represent very useful nitrogen sources and may be directly involved in various plant and soil processes.

Another use of enzymes is to slowly liberate bound active groups. For example pyrethrumn can be bound to a suitable substrate group. Enzyme action to liberate this active component makes it available for controlling root attaching insects. This delay could be adjusted (by concentrations and selection) to coincide with (for example) early root growth after germination of seeds i.e. there is a delay comparable to a sowing and germination period. As can be appreciated other active components, and delays, can be considered. Use of synergistic or co-agents can be considered. For the above example this may include bound ethers of pinene and piperonyl derivatives and methylene dioxyphenyl groups.

A further possible combination includes the inclusion of an organic phosphate ester and a phosphorylase enzyme, the combination being characterised so as to produce a soluble phosphate and/or a phosphorus acid after application to a substrate or in favourable conditions. Again the role of phosphorus and phosphorus compounds in soil and plant processes are well documented.

WO 00134413 WO 00/44 13PCTINZ99OOIOS A further point for consideration is that a number of enzymes require the presence of copper and/or iron to work effectively. Accordingly, it may be of benefit to include copper and/or iron in various embodiments, though in a chelated or complexed form inactivating them against thickening of the clathratic components.

The various combinations proposed thus far, and it is considered that components may be included from any one or more of the various groups and categories discussed previously, have been directed to processes improving or involving soil processes and/or humus. However, being an agricultural chemical it is also envisaged that, like many other agricultural chemicals, other components may be included which need to be applied to the same application area. Accordingly, it is also envisaged that various embodiments of the present invention may include herbicides, insecticides, fungicides etc.

Care, however, should be given to ensure that other included components don't actively prevent what the present invention attempts to achieve.

Accordingly, the use of fungicides should be controlled judiciously to ensure that beneficial fungi or biological organisms are not overly suppressed unless there is a particular reason for doing so. On the contrary, the inclusion of the present invention with herbicides may be of advantage when clearing areas for future cultivation. The humus enhancing properties of the various compositions can assist in the decay and entry into the soil of plant matter affected by the herbicide. This may be of significant advantage to many farming and cultivation techniques.

The method of application of the present invention may also vary. As has been mentioned previously, the preferred embodiments are those which can be subsequently diluted in a carrier, such as water, and applied to a WO 00/34413 WO 0034413PCT[NZ99/00208 substrate. This may be by conventional methods for liquid application in agriculture and horticulture.

Other embodiments may comprise the application of the present invention over a solid material. In many instances this may be the application of a diluted embodiment of the present invention onto a suitable substrate material. This substrate material may be shredded plant or animal matter, such as compost, potting mixes, fertilising materials etc. In some instances the properties of the present invention may accelerate composting of the bulk substrate material, and this is one possible main use of the present invention. However, it may also be an intermediate step with the bulk solid material being used as the carrier for the present invention for subsequent distribution where needed.

Seed coating is another example. The use of enzymes to delay the release of useful components is an option, and has been discussed earlier.

In practice, liquid compositions will be applied to a soil or substrate. At this point mucilagenous reactions commence due to the polyvalent cations normally present. Their soil concentration, along with the carboxyalkyl.

cellulose salt concentration, will have an effect on the rate of thickening but will typically be of suflk-ient time to permeate into the soil along with carried components.

Adjustments can be made to alter the rate of thickening. This may be by the separate or co-administration of polyvallent cations to the sail or substrate. Altering the concentration of the carboxyalkyl cellulose salt is another option, as is the combination of carboxyalkyl cellulose with synthetic polymers or natural polymeric soil conditioners.

BEST MODES FOR CARRYING OUT THE INVENTION WO 00134413 PCTINZ99/00208 Examiple 1 A basic embodiment of the present invention comprises a water soluble carboxyalkyl cellulose, preferably in a dried form.

This can be prepared through the reaction of cellulose with sodium chloroacetic acid and in the presence of sodium hydroxide. This yields a sodium salt of methylcarboxy cellulose as well as sodium chloride and water. The cellulose product should be separated from the salt during the crystallisation process.

Typically the resulting monobasic salt of carboxyalkyl cellulose will form a viscous solution in water. This viscosity at least partially depends on the length of the chain of beta-glucose 1,4 linkages and the concentration of the salt. At this stage no mucilagenous reaction has occurred. This viscosity is useful for helping suspend or resist settling of dispersed solid material (such as in the ensuing examples) until mucilagenous reactions are initiated. To render the blended solid material into solution without large lumps forming very small pills are made, which are about the size of confectionery "hundreds and thousands". The large surface area per unit volume exposed to the water prevents clumping into lumps.

The resulting carboxyalkyl cellulose salt has the property of forming mucilagenous material with clathratic properties when coming into contact with cations having a valency higher than 1. Examples of cations likely to be encountered in various substrates include Ca 2 Mg' Mn 2 Fe' Fe' AhI', Zn 2 Co" Co' B' Co 2 Mo etc.

In use, the above material is a blended mixture that has water added for subsequent application in a liquid form to soil or other substrates.

Dilution ratios may be calculated on the basis of the quantity of included M. WO 00/34413 PCT/NZ99/00208 components one wished to add. However, the quality and nature of the land, and whether repeat applications are intended, will all have a bearing on the diluation ratios and quantity applied per area.

Example 2 To a base type embodiment such as that of Example 1, are included a number of plant essential elements. This may include nitrogenous soluble components, providing they are not compounds having polyvalent cations Ca(NO, 3 2 Also included may be potassium salts, various soluble phosphorus compounds (once again ensuring that there are no free polyvalent cations present when in solution) and sources of sulphur (the same comments on polyvalent cations apply).

There may also be included various other trace elements. However as these typically comprise elements capable of forming polyvalent ions, it is desirable that these elements are bound in a complexed or chelated form.

Preferred elements for use in the present invention (apart from the NPKS elements) include magnesium, boron, cobalt, manganese, zinc, selenium, copper, molybdenum, and iron. This list is not intended to be exhaustive.

The proportions of these added components will typically resemble those of many fertilising mixes though a degree of user choice and preference is available here. If particular deficiencies are diagnosed in a particular substrate, then compensation may be made for that deficiency in the various embodiments of this example.

Example 3 These examples include various enzymes.

11-11- 1.11-1-1 WO 00/34413 PCT/NZ99/00208 Example 3a Here, to an embodiment such as described in Example 1, a carboxylesterase and/or hydrolase enzyme is included. Preferably enzymes of these groups are of the type which break down cellulose, including the clathratic water soluble cellulose product present in the invention. These processes can release energy in the form of heat which can assist in the germination of seeds, the production of more bacteria, acceleration of the growth of fungi and other organisms, as well as accelerating certain soil processes. In cold climates this may provide some significant advantage though the degree of the effect will depend to a certain extent on a number of variables, including the quantity of various cellulose materials present and the distribution of the enzyme.

Example 3b Included with an embodiment such as described in Example 1, is both an amide and a hydrolising enzyme, hydrolase. Given favourable conditions, such as application to the substrate, ammonia gas can be generated according to the following general formula:

R-CONH

2 R-COOH NH 8 Example 3c Similar to Example 3b, this embodiment hydrolises esters with carboxylesterases. The result is the release of urea which is a rich source of nitrogen. As a variation, if a substituted amine derivative of urea is used e.g. R-NH-C(=NH)(NH 2 then the result of hydrolysis will also produce an amine according to the following general reaction: R-NH-C(=NH)(NH,) R-NH 2 NH1-C(=O)(NH).

19 WO 00134413 WO 00/44 13PCT/NZ99/00208 Example 3d In this variation there is present an organic phosphate ester (R-O-P0 3

H

2 along with a phosphorylase enzyme: R-O-P0 3

H

2 R-OH 1 P0 4 Example 4 When humus has been destroyed or last in soils, the moisture generally cannot be held. As a consequence the soil loses nutrient holding capacity and is subjected to leaching and fixation when solid conventional fertilisers, are applied. By replacing the humus back into the soil the situation is usually reversed. The sooner that this can be achieved, the sooner the problems can be addressed.

Embodiments such as described previously can be implemented by application as a liquid composition to soil or growth substrates.

One preferred method of utilising the present invention is to apply the carbonates and/or oxides of calcium and magnesium to the growth substrate or soil and rotary hoe them in. An alternative is to apply these compounds while ploughing so that they are buried at a preferred depth.

The liquid compositions of the present invention are then applied and react to form a mucilagenous gel due to the presence of the calcium and magnesium ions introduced into the soil, though other ions already present in the soil will also have an effect.

In the first instance where the calcium and magnesium compounds were rotary hoed into the growing substrate, the gels which result from the application of the present invention are distributed from the top of the soil downward. This is useful for sowing seeds by broadcasting or in WO 00/34413 WO 0034413PCT/NZ99/0020S attempting to increase humus levels in the upper layers of the soil. In the second method, the gels tend to form at a lower level which tends to benefit craps having a deeper root system. Root craps in particular can benefit from this second method.

However, it should be appreciated that other methods of applying the present invention may also be considered, and to a large extent will also be influenced by what is intended to be achieved. This may include improvements in crops sown at the same time or shortly thereafter, or generally increasing the quality of the soil.

Example As a further variation, various embodiments of the present invention may include the various micro-organisms, fungi (or biological inhabitants of the soil), as well as the reproductive material for either or both. Preferably these will be soil useftil organisms or fimgi (or biological organisms).

Various texts identifying these organisms and fungi (or biological organisms) are available. Reproductive material is generally widely available and may be included in various embodiments of the present invention.

A substrate which has little nutrients and humus present can be seen in arable land that has water available by irrigation but is close to becoming a desert: for example large broad acre areas in Australia. One formulation to adapt this land for wheat growing includes: A. 15 -35% soluble carboxyalkylcellulose B. 0 -40% minerals, trace elements, NPKS sources C. 5 -20% organic material D. 0 -0.01% enzymes WO 00/344 13 PCT/NZ99/00208 E. 0 hormones, insecticides,herbicides, etc.

F. 0 bound and protected groups to be released by enzyme or chemical action G. remainder various insoluble finely ground materials To a total of 100% by weight.

In a preferred formulation of the above general formulation is used: Sodium carboxymethylcellulose (4000) 25 Kg.

4000 is the viscosity grade indicating 4000 units in the chain of beta 1,4 glucose links. Dilution, with the other ingredients added in a 1 in 10 ratio (that is 1 Kg of product to 10 litres of water), is suitable for suspending 29.5 Kg of finely ground (200 microns) bark compost (ingredient 0).

Component B is best determined by soil tests to determine the levels of macro nutrients present and then producing a prescription to correct the levels to a medium range. The minor trace elements are added at a maintenance level required (in this example) for wheat growing, and may also be at least partially determined from the analysis of wheat. These components are preferable complexes or chelates of the polyvalent nutrients so that when combined with the other components will be less likely to react with ono another. More importantly it will prevent component A from forming a mucilage-gel in solution prior to substrate capplication. One formulation giving the macro nutrients as percentages is: N P K S Na (ingredients obLained from monovalent 27.5 12.2 1 1.4 0.2 compounds).

The trace elements as parts per million WO 00/34413 PCT/NZ99/00208 Ca B Co Cu Fe Mg Mn Mo Zn 500 100 0 200 50 500 50 50 200 of this blend is included in the formulation.

Components C (organic material) These may include the following compounds, or compositions rich in same.

1 Kg Arginine 1 Kg Histidine 1 Kg Leucine 1 Kg Isoleucine 1 Kg Lysine 1 Kg Methionine 1 Kg Phenylalanine (cyclic phenyl group) 1 Kg Threonine 1 Kg Tryptophane (cyclic phenyl group) 1 Kg Valine S Componens D (Enzymes) Vitamins which are essential include vitamins A and D, B, C, E, and folic acid, and vitamin B complex.

Carboxylesterase a simple esterase used to begin the catalytic action of breaking down the large chain of beta, 1,4 glucose linked sodium carboxymethyl cellulose into smaller units. Since the catalytic action of the enzyme's rate of action is proportional not only to the concentration of enzyme, but also the concentration of carboxyester, temperature, pH and cofactors (moisture and co-enzymes) the addition of enzyme can be kept relatively low. Heat will be released and will continue over a long period WO 00/34413 PCT/NZ99/00208 depending upon the concentration of substrate it works upon. Ingredients C include amino acids which are hydrolysed to release heat energy and ammonia as well as urea. Sulphate and phosphate is released from the embodied ingredients F, with the enzyme sulphatase and phosphoralase respectively.

Esterase 1 Gram Phenolsulphatase 1 Gram Glucosulphatase 1 Gram Acid Phosphatase 1 Gram Hexosemonophosphatase 1 Gram Components F (Special Organic Compounds) Glucose 1 Phosphate 2.75 Kg Glucose sulphate ester 1.75 Kg Phenyl sulphate ester 1.00 Kg The above ingredients combined with the enzymes in D slowly release phosphate and sulphate which have been protected by the carboxyalkylcellulose mucilage gel to become available to the root systemof the wheat as it grows.

Component G may comprise fine organic material, such as bark, compost etc.

100 Kg of the blend described above is diluted with 1000 litres of water and applied with the seed on planting. This should be enough to cover 4 hectares.

24 trtty~ ivtfl-ri- WO 00/344 13 PCTINZ99/00208 The present invention has a number of uses. It is envisaged that the main use will be to improve and maintain the condition of arable land. However, in situations where the land is untenable as a growing media, use of the present invention can be used to accelerate its conversion into arable land.

This may necessitate the inclusion of additional organic matter, though it is certainly envisaged that use of the present invention will accelerate the conversion of this land into areas showing suitability for cultivation and plant growth.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof as defined in the appended claims.

Claims (15)

1. A humic composition which includes a clathratic component in the form of at least one of a substantially water soluble cellulose component, a synthetic polymer and a natural polymer, the humic composition being substantially free of polyvalent cations and remaining substantially free of any gel-forming when dissolved in water, the clathratic component being characterised in that the clathratic component undergoes gel formation in the presence of polyvalent cations, thereby imparting thickening to the humic composition.

2. A humic composition as claimed in claim I which includes, as a clathratic substantially water soluble cellulose product, at least one carboxyalkyl cellulose compound or a salt thereof.

3. A humic composition as claimed in claim I or 2 in which the carboxyalkyl cellulose compound is produced by a reaction of cellulose with a halogenated alkali salt of a carboxyl acid and a monobasic alkali.

4. A humic composition as claimed in any one of claims 1 to 3 which includes one or more soluble components selected from the following list, providing they are substantially free of polyvalent cations promoting gel formation: carbohydrates, humic acids, soluble extracts derived from plant matter, soluble extracts derived from animal matter, soluble plant nutrients, enzymes and in particular enzymes associated with soil activity or degradation of soil material, proteins and proteinaceous material, amino acids and amino acid salts and derivatives, peptides and polypeptides, nucleic acids and nucleoprotamines, non-phytotoxic amines and amides and plant essential elements and minerals. A humic composition as claimed in any one of the above claims which includes one or more insoluble components from the following list, providing they are substantially free of polyvalent cations promoting gel formation: plant derived material, animal derived materia!, material derived from the decay or partial decay of substantially organic matter, carbohydrates, plant nutrients, enzymes and in particular enzymes associated with soil activity or degradation of soil material, proteins and proteinaceous material, amino acids and amino acid salts and derivatives, peptides and polypeptides, Snucleic acids and nucleoprotamines, non-phytotoxic amines and amides, and plant Sessential elements and minerals, herbicides, fungicides and/or insecticides.

6. A humic composition as claimed in any one of the above claims which includes one or more components from the following list: biological organisms, bacteria, algae, protozoa, fauna, and fungal material including reproductive material, micro-organisms including reproductive material therefor, and especially of fungi or micro-organisms exhibiting soil activity or activity towards the degradation of soil material.

7. A humic composition as claimed in any one of the above claims which includes an amide and a hydrolysing enzyme.

8. A humic composition as claimed in any one of the above claims which includes an ester and a carboxylesterase.

9. A humic composition as claimed in any one of the above claims which includes a substituted amine derivative of urea and the enzyme carboxylesterase. A humic composition as claimed in any one of the above claims which includes an organic phosphate ester and a phosphorylase enzyme. I1. A humic composition as claimed in any one of the above claims when applied to soil or another substrate.

12. A humic composition as claimed in any one of the above claims when applied to soil or another substrate in conjunction with the application of one or more other compositions which contain substances promoting thickening of the humic composition. t S 13. A method of applying a humic composition as claimed in any one of the preceding claims, the method including the steps of: mixing a predetermined quantity of the composition to a carrier to form a Smixture; and applying the mixture to a substrate.

14. A method of increasing humus in a substrate, the method including the step of applying a composition as claimed in any one of the preceding claims to said substrate.

15. A method as claimed in claim 14, which includes the step of mixing at least one component which is known to promote the formation of humus, either directly or indirectly, with the composition.

16. A method as claimed in claim 15 which includes the step of mixing at least one of the following components, either directly or indirectly, with the composition: carbohydrates, soluble extracts derived from plant matter, soluble extracts derived from animal matter, protein and proteinaceous material, amino acids and amino acid salts and derivatives, peptides and polypeptides, nucleic acids and nucleoprotamines, various non-phytotoxic amines and amides.

17. A humic composition substantially as herein described and with respect to any example thereof.

18. A method of applying a humic composition substantially as herein described and with respect to any example thereof.

19. A method of increasing humus in a substrate substantially as herein described and with respect to any example thereof.