LV10707B

LV10707B - Micronutrient fertilizer composition

Info

Publication number: LV10707B
Application number: LVP-93-95A
Authority: LV
Inventors: Danneskiold-Samsoe Otto
Original assignee: Danneskiold Samsoe Otto
Priority date: 1990-01-04
Filing date: 1993-02-03
Publication date: 1995-12-20
Also published as: WO1991009818A1; LT3610B; EP0509030A1; LV10707A; HUT63594A; HU9202223D0; CA2072372A1; NZ236673A; AU7060791A; LTIP795A; AU642201B2; DK1890D0

Description

1 LV 10707

MICRONUTRIENT FERTILIZER COMPOSITION

FIELD OF THE INVENTION

The present invention relates to a solid micronutrient fertilizer composition cotnprising micronutrients in the form of mētai salts together with at least one water-soluble nitrate, to a method for preparing the micronutrient fertilizer composition, and to a method for fertilizing crops using the micronutrient fertilizer composition.

BACKCROUND OF THE INVENTION

It is well-known in the field of agriculture that the optimum devel-opment of plants is dependent upon the plants being provided with the proper balance of ali of the various essential nutrients. The lack of just a single essential nutrient, which perhaps is only necessary for proper growth in extremely small quantities, can lead to poor growth, deficiency symptoms and a drastic reduction in crop yield. Even though ali of the other essential nutrients may be present in optimum quantities, the one nutrient which is present in a sub-optimum quan-tity may thus become the limiting factor, thereby seriously retarding the development of the plants.

On the other hand, less is knovm about how the various micronutrients are to be provided so as to be available to the plants in suitable amounts, thereby securing optimum growth, while at the same time being in a form which allovs them to be applied in a practical and economical manner. Thus, the lack of a practical and economical way of applying readily available micronutrients to, for example, field crops may result in the crops receiving a sub-optimum amount of certain essential micronutrients.

Standard macronutrient fertilizers, e.g. nitrogenous fertilizers or N-P-K fertilizers, often lack a nuraber of the essential micronutrients, although this may not present any acute, readily apparent 2 problem, since most soils contain a certain reserve of these micro-nucrients. Hovever, if the soil is not replenished with these micro-nutrients, the result in the long run will be a depletion of the micronutrients and there'fore a reduced yield. It is therefore neces-sary to provide the essential micronutrients on a regular basis in order to sustain optimum plant grovth and maximum yields. T’nis often presents a problem in practice, hovever, since it often proves dif-ficult to apply fertilizer compositions in a form which is readily available to the plants and which also satisfies the requiremenc that the micronutrients must be relatively inexpensive and convenient to apply·

Thus, a micronutrient fertilizer composition should fulfill the following criteria in order to secure the best effect and optimum plant growth: 1) it should contain a number of the essential micronutrients, and preferably ali. of the essential micronutrients which are not readily available from the soil; 2) it should be formulated and applied so as to ensure the best possible absorption of the micronutrients by the plant; 3) it should be applied at the proper time in relation to the growth of the plant, i.e. especially at the beginning of the plant's growth cycle and when the soil temperature is at least about 5®C; and M it is desirable that it can be applied together with Standard commercial nitrogenous or N-P-K fertilizers, and that it is relatively inexpensive.

It has now been found that crop plants can easily and inexpensively be provided with a suitable balance of the essential micronutrients in a readily available form by means of a novel solid micronutrient fertilizer composition comprising the micronutrients in the form of mētai salts together with at least one water-soluble nitrate. 3 LV 10707

BRIEF DESCRIPTION OF THE INVENTION

One aspecc of the invention relaces to a micronutrient fertilizer composition in the form of dry aggregate bodies, the fertilizer composition being adapted to be mixed with a macronutrient fertilizer composition, each aggregate body comprising salts of at least 2 metāls selected from the group consisting of Cu in an amount of 300-15,000 g per 100 kg of the composition, exclusive of any binder, Mn in an amount of 150-8000 g per 100 kg of the composition, exclusive of any binder, Zn in an amount of 50-4000 g per 100 kg of the composition, exclusive of any binder, Co in an amount of 1-200 g per 100 kg of the composition, exclusive of any binder, and Mo in an amount of 5-500 g per 100 kg of the composition, exclusive of any binder, as well as at least one water-soluble nitrate vrhich is not in the form of a salt of the above-mentioned metāls, the ratio betveen micronutrients and macronutrients in the micronutrient fertilizer composition being substantially above the ratio in which the micro-nutrients and macronutrients in question are required by crop plants. A second aspect of the present invention relates to a method for preparing a micronutrient fertilizer composition in the form of dry aggregate bodies which are adapted to be mixed with a macronutrient fertilizer composition, the method comprising dry mixing vithout any substantial addition of water salts of at least 2 metāls selected from the group consisting of Cu, Mn, Zn, Co and Mo as well as at least one water-soluble nitrate which is not in the form of a salt of said metāls, said salts and said nitrate being in the form of pow-ders, the ratio betveen said micronutrients and said macronutrients being substantially above the ratio in vhich said micronutrients and said macronutrients are required by crop plants, to obtain an in-timately mixed micronutrient mixture, and mixing the resulting micronutrient mixture with a binder to obtain said micronutrient fertilizer composition in the form of dry aggregate bodies. A third aspect of the invention relates to a solid fertilizer mixture comprising, as a first component, the above solid micronutrient 4 fercilizer composition, and as a second component, a solid macro-nutrienc fercilizer composicion comprising at leasc N, P and/or K. A fourch aspecC of che invencion relates to a method for fertilizing crops, the mechod comprising applying to the crops or to the soil the above fertilizer mixture or the above micronutrient fercilizer com-position.

The micronutrient fertilizer composition according to the invention fulfills ali of the above-menti,oned criteria, i.e. it contains sever-al or °f c^e essential micronutrients in a form which ensures effective absorption by che plants, it is easily applied at the desired time cogether vith, e.g., Standard commercial nitrogenous or h-P-K fertilizers, and it is formulated from micronutrient-containing compounds which are relatively inexpensive. Furthermore, as shown below in the Examples, the value of the novel micronutrient fercilizer composition has been proven by significantly increased yields in field trials over several years.

DETAILED DISCLOSURE OF THE INVENTION

The terms "micronutrient fertilizer composition" and "fertilizer composition of the invention" refer to the above-mentioned composition comprising micronutrienes in the form of mētai salts together with at least one water-soluble nitrate. It is clear that the composition will also contain nitrogen, and it vill typically also contain a certain amount of various maeronutrients, but the ratio of micro-nutrients to maeronutrients in the fertilizer composition vill be substantially higher than the ratio in vhich the nutrients in ques-tion are required by crop plants. The micronutrient fertilizer composition of the invention is, in other words, not designed to be used alone as the sole fertilizer for a crop, but rather together vith, e.g., a commercial maeronutrient fertilizer. While the amounts of the various micronutrients required by different plants may vary, micro-nutrients are by definition those nutrients vhich are required in only very small amounts, and these amounts lie vithin certain ranges vhich are knovn by persons skilled in the art. For field crops, the 5 LV 10707 folloving macro- and micronutrienes are typicallv required in che folloving amounts (per heetare per year) :

Macronutrienes Micronucrienes N 40-250 kg Fe 100-10,000 P 8-40 kg B 5-500 g K 25-220 kg Cu 10-75 g s 4-80 kg Mn 20-600 g Mg 5-100 kē Zn 10-500 g Ca 10-180 kg Co 1*10 g Mo 0.5-10 g Na *2-40 kg

Wich reference to the above amounts of nutrients typically required in field crops, the term "the ratio between micronutrients and maero-nutrients in the micronutrient fertilizer composition being substan-tially above the ratio in which the micronutrients and maeronutrients in question are required by crop plants" refers to the fact that the ratio between the micronutrients and maeronutrients in the composition is typically at least twice the ratio in which the micronutrients and maeronutrients in question are required by che plants, more typically at least 10 times this ratio, more typically at least 20 times this ratio, more typically at least 50 times this ratio. such as at least 100 times this ratio, as will be evident from the above amounts and from that which is deseribed herein with reference to the individual micronutrients as well as from the examples. VJhile the fertilizer composition in certain cases may be applied alone, it is particularly adapted to be used as a supplement to Standard maeronutrient fertilizers, for example N-P-K fertilizers or nitrogenous fertilizers, since these fertilizers typically are not designed to provide essential micronutrients.

The term "maeronutrient fertilizer composition" refers to a Standard fertilizer composition adapted mainly for providing one or more of the important maeronutrients, in particular N, P and/or K. Such fertilizers, for example coramercial N-P-K fertilizers or nitrogenous 6 fertilizers, are applied in relatively large amounts to crop plants or soil in order to satisfy the plants' requirements for the maior nutrients. However, as explained above, these fertilizers often lack a number of the essencial micronutrienes, or the micronutrients mav be present in a form which does not allow absorption in sufficient quantities by the plants.

The expression "water-soluble nitrate" refers to a nitrate which is readily soluble in water. The water-soluble nitrates used in the context of the present invention will furthermore be those which are agriculturally acceptable. In particular, the water-soluble nitrate may be an alkali or alkaline earth mētai nitrate, e.g. sodium ni-trate, potassium nitrate or calcium nitrate, or ammonium nitrate.

The fertilizer composition of the invention may of course contain two or more of such vater-soluble nitrates as well as vater-soluble nitrates other than the above-mentioned, for example calcium ammonium nitrate .

As mentioned above, the fertilizer composition of the invention comprises salts of at least 2 metāls selected from the group consist-ing of Cu, Mn, Zn, Co and Mo. Hovever, since ali of these metāls belong to the group of essential micronutrients, the fertilizer composition will typically comprise salts of at least 3 of the metāls, more typically salts of at least 4 of the metāls. A particular-ly preferred fertilizer composition is one which comprises salts of ali 5 metāls.

In addition to the above-mentioned micronutrients, it may be desir-able to incorporate certain other important micronutrients into the fertilizer composition of the invention. These inelude B, Fe, C1,

Na, and I, and perhaps Se, Rb, Ag, Ti and V. In particular, it may be desirable to inelude a boron-eontaining salt and/or an iron salt in the fertilizer composition, as both of these elements are essential micronutrients which may be lacking in certain cases. It may further be of interest to incorporate into the fertilizer composition certain elements which are not believed to be essential micronutrients for the majority of plant species, but which are essential for humāns and animals, e.g. selenium. 7 LV 10707

It will be understood by a person skilled in the art that the precisc-content of the various micronutrients in the micronutrient fertilizer composition may vary considerably according to such factors as the type of soil, the crop being grovn, the climate and the particular niixture of micronutrients desired based on these and other factors. Therefore, it is difficult to provide general guidelines as to speci-fic amounts of different nutrients which will be present in the fertilizer composition in ali cases. Hovever, the folloving amounts (calculated on the basis of the weight of the nutrient element (atorr) in question) are provided as a general non-limiting guideline as to amounts which are believed to be suitable for a vide variety of soils, crops and climates. The specific amounts of the various micronutrients to be used in each particular case vill able to be deter-mined by a person skilled in the art, for example on the basis of the results of an analysis of the nutrient status of the soil and/or plants, taking into consideration the other factors mentioned above.

Vhen a copper compound is present in the fertilizer composition of the invention, the amount of Cu vill typically be about 300-15,000 g. more typically about 1000-8000 g, such as about 2000-5000 g, per 100 kg of the micronutrient fertilizer composition, exclusive of anv binder. When a manganese compound is present in the fertilizer com-position of the invention, the amount of Mn vill typically be about 150-8000 g, more typically about 500-3000 g, such as about 1000-2000 g, per 100 kg of the micronutrient fertilizer composition, exclusive of any binder. When a zinc compound is present in the fertilizer composition of the invention. the amount of Zn vill typi-cally be about 50-4000 g, more typically about 150-2500 g, such as about 300-1500 g, per 100 kg of the micronutrient fertilizer composition, exclusive of any binder. When a molybdenum compound is present in the fertilizer composition of the invention, the amount of Mo vill typically be about 5-500 g, more typically about 10-300 g, such as about 20-150 g, per 100 kg of the micronutrient fertilizer composition, exclusive of any binder. Vhen a cobalt compound is present in the fertilizer composition of the invention, the amount of Co vill typically be about 1-200 g, more typically about 5-100 g, such as 8 about 10-50 g, per 100 kg of the micronutrient fertilizer composi-tion, exclusive of any binder.

Furthermore, vhen a boron-containing compound is present in the fertilizer composition of the invention, the atnount of B will typi-cally be about 100-7000 g, more typically about 500-4000 g, such as about 1000-2000 g, per 100 kg of the micronutrient fertilizer compo-sition, exclusive of any binder. When an iron compound is present in the fertilizer composition of the invention, the amount of Fe will typically be about 100-6000 g, more typically about 500-3500 g, such as about 750-1750 g, per 100 kg of the micronutrient fertilizer composition, exclusive of any binder.

Similarly, it is difficult to provide general guidelines as to speci-fic amounts of the vater-soluble nitrate to be used, again due to the variables mentioned above. Hovever, it is believed that in most cases, a suitable amount of N (calculated as pure N) in the form of one or more v/ater soluble nitrates will be about 500-25,000 g, typi-cally about 1000-15,000 g, such as about 2000-10,000 g, per 100 kg of the micronutrient fertilizer composition, exclusive of any binder,

In connection with the amounts of the various micronutrients and NO3-N mentioned above, it will be clear to a person skilled in the art that the amount of the micronutrient fertilizer composition to be applied to the soil or to the plants must be chosen according to the quantities of the various nutrients in the fertilizer composition, taking into consideration that vhile the micronutrients are essential in small quantities for optimum growth, they may also be damaging or even toxic to the plants if applied in excessive amounts.

As mentioned above, the micronutrient fertilizer composition will in addition to a number of micronutrients also contain certain macro-nutrients. One of these is obviously N, since the fertilizer composition comprises at least one vater-soluble nitrate. In addition, the fertilizer composition will typically contain one or more of the macronutrients S, P, Mg, Ca and K, for example in the form of diam-monium phosphate, potassium phosphate, potassium chloride, potassium sulfate and/or magnesium sulfate. 9 LV 10707

The mētai salts of the fertilizer composition of the invention will typically comprise sulfates, nitrates and/or oxides. The mētai salts may also be in the form of halogenides (e.g. chlorides), hydrogen sulfates, carbonates and/or hydrogen carbonates. In addition, copper 5 may be present in the fertilizer composition in the form of, e.g., copper oxychloride, and molybdenum may be present in the form of, e.g., ammonium molybdate or sodium molybdate.

In particular, one or more of the mētai salts will often be a sul-fate, since sulfate salts of a number of the above-mentioned metāls 10 are relatively inexpensive, and since it has been sh'ovm that the desired results may be achieved by the use of such sulfates.

Thus, a preferred fertilizer composition according to the present invention comprises at least copper sulfate or copper oxychloride. manganese sulfate and zinc sulfate. 15 The fertilizer composition of the invention furthermore advantageous-ly comprises at least one compound selected from the group consisting of iron (II) sulfate, Solubor® (soluble sodium borate,

Na2BgOi3 - borax, ammonium molybdate, sodium molybdate and cobalt sulfate. 20 As mentioned above, micronutrient fertilizer compositions according to the invention may be prepared by a method comprising dry mixing without any substantial addition of water salts of at least 2 metāls selected from the group consisting of Cu, Hn, Zn, Co and Mo as veli as at least one v/ater-soluble nitrate which is not in the form of a 25 salt of said metāls, said salts and said nitrate being in the form of povders, the ratio between said micronutrients and said macronutri-ents being substantially above the ratio in which said micronutrients and said macronutrients are required by crop plants, to obtain a micronutrient mixture, and mixing the resulting micronutrient mixture 30 vith a binder to obtain said micronutrient fertilizer composition in the form of dry aggregate bodies. 10

The term "mixing vithout any substantial addicion of vater" refers to the fact the mixing of the mētai salts and the nitrate is carried out using a dry procesi;. Thus , while it in certain cases may be desirabli to use a certain amount of water in the production process, this amount will generally be quite limited, so that the mētai salts and nitrate will not be processed as, e.g., Solutions or pastes.

The term "povders" refers to the fact that the mētai salts and the nitrate are substantially in the form of powders containing discrete fine dry pārticies of the materiāls in question. This term is also meant to include, e.g., materiāls having a somewhat grainy consisten- cy.

While it is possible to mix the powdery micronutrient mixture with the binder immediately after the powdery mixture is obtained, it is preferred that the micronutrient mixture having a powdery consistencv is allowed to stand, prior to mixing with the binder. until its consistency has changed from a dry, powdery consistencv to a moist, sandy consistency and until the individual pārticies of said mixture have acquired a crystalline or crystai-1ike appearance, It has thus been found that the beneficial effect of the micronutrient fertilizer composition is improved if the powdery mixture is alloved to stand for a period of time prior to mixing with the binder. This time period is preferablv at least about 2 veeks. more preferablv at least about 4 veeks, most preferably at least about 6 veeks. During this "aging" period, the hygroscopic salts of the mixture absorb moisture from the air, vherebv the mixture acquires the above-mentioned moist. sandy consistency and crystalline appearance, thereby making it easier to process than a povdery mixture. It has been found that after a period of about 6 veeks or more at ambient temperature and humidity, the micronutrient mixture, vhich vas originally in the form of a povder, generally has acquired the desired crystalline appearance and a consiscency resembling that of slightly moist sand.

While not being a preferred method, it is contemplated that the micronutrient mixture having a povdery consistency, in addition to or as an alternative to being alloved to stand prior to mixing vith the binder, may be moistened vith vater and subsequently mixed so as to 11 LV 10707 distribute the water uniformly throughout the mixcure, thereby achieving che desired moist consistency.

It will be clear to a person skilled in the art that the salts and nitrate used for preparing the micronutrient mixture will typically be sieved and/or ground as necessary before mixing and/or afcer mixing.

While noc vishing to be bound by any particular theory, it is believed that the beneficial effect of the micronutrient fertilizer composition of the invention is obtained as explained in the follow-ing.

It is well-known that in order to obtain the benefit of micronutri-ents which are applied to crop plants or to the soil, it is necessary for the micronutrients to be in a form which is easily absorbed by the plants. This in turn means that the micronutrients must be readi-ly soluble in water. This may seem to be relatively straightforward in principle, but in practice difficulties are presented by, among other things, the fact that the desired readily soluble mētai salts are hygroscopic and therefore are difficult to formulate in a form which is easily applied to the plants or soil. On the other hand, formulations of the micronutrients which are easily applied, e.g. using lime, may suffer from the disadvantage of being less soluble and therefore less available to the plants.

The novel micronutrient fertilizer composition of the invention is at the same time both easy to apply and readily soluble in water and therefore readily absorbed by plants. The formulation of the mētai salts and the water*soluble nitrate together with a binder allows the fertilizer composition to be brought into the form of aggregate bodies, e.g. pellets or granules, which are easily applied together with Standard commercial fertilizers. As to the micronutrients in the fertilizer composition being readily soluble, it is believed that this results from the fact that in each individual aggregate body, the mētai salts are intimately mixed wich or in close proximity to the water-soluble nitrate. Thus, in the presence of vater, e.g. in the soil or from direct precipitation, che micronutrient ions vill be 12 dissolved along vith the nitrate ions, and the soil vater will there-fore contain a relatively homogeneous mixcure of, among ocher things, the micronutrient ions and nitrate ions. It is believed that the presence of the nitrate ions results in the micronutrients being in a 5 form vhich is more readily accessible to the plants, perhaps by virtue of a reduced tendency to be adsorbed by soil pārticies, there· by ensuring a better absorption of the micronutrients. It is vell-knovn that nitrate ions are readily absorbed by plants, and it has been shown during the testing of the fertilizer composition of the 10 invention that the use of a greater amount of the water-soluble nitrate in the composition results in an increased yield.

As mentioned above, the formulation of the mētai salts and the vater-soluble nitrate together with a binder allows the fertilizer composition to be brought into a form vhich is easily applied together vith 15 Standard commercial fertilizers and which also is readily soluble in water. Any agriculturally acceptable material vhich is capable of binding the mētai salts and the vater-soluble nitrate together and vhich allovs the mētai salts and nitrate to be dissolved in vater may be employed. Thus, the binder is preferably an agriculturally accep-20 table vater-soluble organic binder, e.g. a plant product or a natūrai, semi-synthetic or synthetic polynjer. Examples of suitable binders are those selected from the group consisting of plant Products such as vheat bran, vheat flour or savdust; polysaccharides and polysaccharide derivatives such as starches, starch derivatives 25 (e.g. Sta-Rx® 1500, Emdex® and Explotab®), celluloses, microcrystal - line cellulose, cellulose derivatives, alginates, lactose, mannitol or sorbitol; proteīns such as gelatins; gums such as acacia; and synthetic polymers such as polyethylene glycols (e.g. polyethylene glycol 4000 or 6000) or polyvinyl pyrrolidone. Another possible 30 binder is calcium monohydrogen phosphate. It may furthermore be advantageous in certain cases to use a combination of binders.

The ratio betveen the amount of binder and the amount of the nutrient compounds (i.e. the mētai salts and vater-soluble nitrate(s) as veli as any other nutrient compounds present) in the fertilizer composi-35 tion of the invention vill of course vary according to the nature of the particular binder used, e.g. according to such factors as its 13 LV 10707 binding ability and specific gravity, but it will generally be desir-able that the amount of the binder is ķept to a minimum so as to keep the weight and bulk of the fertilizer composition to a minimum.

The term "aggregate bodies" refers to the fact that the fertilizer composition is in the form of individual units, each of which com-prises the mētai salts mixed with or in contact with the vater-solu-ble nitrate. The aggregate bodies may, for example, be in the form of pellets, granules and/or beads, or they may be in prilled form. The mētai salts and the water-soluble nitrate are according to the pres-ent invention preferably intimately mixed vithin each individual aggregate body. whereby each aggregate body comprises a substantiallv homogeneous mixture containing pārticies of the mētai salts and pārticies of the water-soluble nitrate(s). The term "pārticies" refers to pārticies which may have various sizes and shapes, for example, but not limited to, crystalline pārticies, granular pārticies, powder or dust pārticies, etc. The individual aggregate bodies in vhich the mētai salts and the water-soluble nitrate are intimately mixed may also be coated with any desired substance.

Typically, substantially ali of che aggregate bodies will have at least one dimension of at least about 0.5 mm, and substantially ali of the aggregate bodies will often have at least one dimension of at least about 1 mm. When che fertilizer composition of the invention is in the form of, e.g., pellets, substantially ali of the aggregate bodies will typically have at least one dimension of at least about 3 mm.

The choice of the form and size of the individual aggregate bodies will depend upon such factors as the particular nutrient compounds and binders used as veli as the form and size of the individual units of the macronutrient fertilizer with vhich the micronutrient fertilizer composition of the invention is to be applied. It vill be obvious to a person skilled in the art that the size, shape and specific gravity of the aggregate bodies raust be chosen so that the aggregate bodies of the micronutrient fertilizer composition are compatible vith the individual units of any macronutrient fertilizer composition it is to be applied vith, in order to ensure that a iu relatively homogeneous distribution of Che micro- and macronutrienc fertilizer composicions, respeccively, may be obtained.

The aggregace bodies of che micronutrient fercilizer composicion may be prepared using mechods knovm in che arc for che preparacion of fertilizer compositions. For example, for che preparation of pellecs, che composicion may be prepared by first thoroughly mixing ali of the micronutrient compounds and the uater-soluble nitrate. The micro-nucrient-concaining mixture is then mixed wich the binder and, if necessary, with a limited amount of water or another liquid. Pellets may then formed from this raixture, e.g. using a Standard pelleting machine for feed pellecs. Essentially the same propecfure may be followed for the preparacion of, e.g., granules, with the exception that a machine for the preparation of granules is used instead of a pelleting machine. Similarly, other types of aggregate bodies, for example coated aggregate bodies, may be prepared by methods knovn in the art.

As mentioned above, another aspect of the invention relates co a solid fertilizer mixture comprising, as a firsc component, the above solid micronutrient fertilizer composicion, and as a second component, a solid macronutrient fercilizer composition comprising at leasc N, P and/or K.

The macronutrient fertilizer component of the fertilizer mixture will typically be a Standard commercial fertilizer, in particular ε nitro-genous or N-P-K fertilizer. Such fertilizers cypically comprise nitrogen in che form of urea, nicrate and/or ammonium, as well as varying amounts of P, K, Ca, Mg and/or S.

The macronutrient fertilizer component of che fertilizer mixture mav also be an organic fertilizer.

As explained above, one of the advantages of the micronutrient fercilizer composicion of the invention is that it may be applied to the soil or crops together with, e.g., Standard commercial nitrogenous or N-P-K fertilizers, Therefore, it is desirable that the fertilizer mixture comprising the micronutrient fertilizer component and the 15 LV 10707 macronutrient fertilizer component be formulated so as to allow for a uniform distribution of the micronutrient - containing component and the macronutrient-containing component upon application of the ferti-lizer to a crop or soil. This is achieved in practice by ensuring Chat the two components have a physical form, i.e. shape, size and specific gravity, which is compacible with each other. The individual units of the two components need not necessarily have exactly the same shape, size or specific gravity, but they should be formulated so that an approximately equal distribution of the two components of the mixture in the field may be achieved. The individual units of the components of the fertilizer mixture will therefore typically be in the form of pellets, granules and/or beads and/or in prilled form.

As mentioned above, the micronutrient fertilizer composition of the invention may in certain cases be applied alone, but will typically be applied together with a macronutrient fertilizer, i.e. in the form of the above fertilizer mixture.

In a further aspect, the present invention thus relates to a method for fertilizing crops using the above fertilizer mixture or the above micronutrient fertilizer composition.

As explained above, the amount of the micronutrient fertilizer component in the fertilizer mixture, or the amount of the micronutrient fertilizer composition, in the case of the micronutrient fertilizer composition being applied alone, which is to be applied to the soil in which crops are growing or are to be grovm or which is to be applied to the plants must be chosen according to the quantities of the various nutrients in the fertilizer composition. The proper amount to be applied will be able to be determined in each particular case by a person skilled in the art. It is preferred that the micro-nutrient-containing fertilizer composition or the micronutrient fertilizer composition is applied relatively early in relation to the crop in question, as this has been shovm to provide the best result.

Due to variations in soils, etc., it is difficult to provide precise amounts of the micronutrient fertilizer component in the fertilizer mixture or of the micronutrient fertilizer composition to be applied 16

However, in most cases, the micronutrient fertilizer component in che fertilizer mixture, or the micronutrient fertilizer composition, will be applied to the crops or to the soil in an amount of about 1-100 kg/ha, exclusive of any binder. Typically, the micronutrient fertilizer component in the fertilizer mixture, or the micronutrient fertilizer composition, is applied to the crops or to the soil in an amount of about 5-60 kg/ha, more typically in an amount of about 10· *0 kg/ha, exclusive of any binder. In a loam soil. it has been found that good results were obtained using an amount of about 10-35 kg/ha, and in particular in an amount of about 15-30 kg/ha.

The invention will be further illustrated by the following non-limi-ting examples . EXAMPLE 1 A micronutrient fertilizer composition in the form of pellets com-prising the folloving components was prepared: kg

Diammonium phosphate 1.304

Potassium sulfate 1.304

Magnesium sulfate 7.391

Calcium nitrate 2.609

Sodium nitrate 1.304

Iron (II) sulfate 1.304

Copper sulfate 0.870

Copper oxychloride 0.870

Manganese sulfate 1.261

Solubor® 1.304

Zinc sulfate 0.435

Ammonium molybdate 0.044

Total 20.000

The composition was prepared by first thoroughly mixing ali of the above ingredients manually using a shovel, after which the mixture, 17 LV 10707 which had a dry, powdery consistency, was alloved to stand at ambient temperature and relative huniidity for a period of about 1 1/2 months. The micronutrient-containing mixture, which then had a moist, sandy consistency, with the individual pārticies having a crystalline appearance (as seen under a raagnifying glass), was then mixed with about 2 parts (by weight) wheat bran as a binder to about 13 parcs (by veight) of the niixture. Pellets were then formed from this mix-ture using a Standard pelleting machine for feed pellets. Steam was used during pressing in order to ensure the cohesiveness of the components of the pellets. The resulting pellets’had a diameter of about 3.5 mm and a typical length of about 5-10 mm. EXAMPLE 2 A micronutrient fertilizer composition was prepared as in Example 1. The composition comprised the folloving components:

Diammonium phosphate Potassium sulfate Magnesium sulfate Calcium nitrate Sodium nitrate Iron (II) sulfate Copper sulfate Copper oxychloride Manganese sulfate Solubor® Zinc sulfate Ammonium molybdate Cobalt sulfate kg 1.303 1.303 7.383 2.606 1.303 1.303 0.869 0.869 1.260 1.303 0.434 0.04 U 0.022

Total 20.000

The nutrient content of the composition was as follows:

N

P 917 g 300 g 18 K 534 8 Mg 728 g Ca 606 g Na 352 g S 1653 g Fe 260 g Cu 652 g Mn 340 g B 271 g Zn 95 g Mo 21 g Co 7' g EXAMPLE 3 A micronuerient fertilizer composition was prepared as in Example 1. The composition comprised the folloving components: kg

Diammonium phosphate 1.235

Potassium sulfate 1.235

Magnesium sulfate 6.996

Calcium nitrate 2.^69

Sodium nitrate 1.235

Iron (II) sulfate 1.235

Copper sulfate 0.823

Copper oxychloride 0.823

Manganese sulfate 1.193

Borax 2.284

Zinc sulfate 0.412

Ammonium molybdate 0.041

Cobalt sulfate 0.021

Total 20.002

The nutrient content of the composition vas as follovs: N 866 g 19 LV 10707

P 284 g K 506 g Mg 689 g Ca 574 g Na 608 g S 1636 g Fe 247 g Cu 616 g Mn 322 g B • 251 g Zn 90 g Mo 19 g Co 7 S EXAMPLE 4 A micronutrient fertilizer composition may be prepared as in Example 1 using the following components : kS Ammonium nitrace 2.000 Diammonium phosphate 1.235 Potassium nitrate 0.660 Potassium sulfate 0.610 Magnesium sulfate 7.000 CalciujTi nitrate 2.470 Sodium nitrate 2.000 Iron (II) sulfate 1.235 Copper sulfate 0.823 Copper oxychloride 0.823 Manganese sulfate 1.193 Borax 2.284 Solubor^ 0.400 Zinc sulfate 1.235 Anunonium molybdate 0.041 Cobalt sulfate 0.021 20

Total 2^.030

Such a composition comprises the folloving nutrients in the folloving amounts: N 1771 g P 288 & K 501 & Mg 690 6 Ca 568 g Na 859 ē S 1608 g Fe 247 g Cu 616 g Mn 322 g B 334 g Zn 272 g Mo 5 g Co 4 g C1 135 g EXAMPLE 5

The effect of che micronutrient fercilizer compositions of the above examples on yields of vinter wheat was determined.

The micronutrient fertilizer compositions were applied for several seasons in varying amounts to vheat grovn in 100 m^ tēst plots (4x25 m) in a loam soil. The compositions applied were those of Example 2 ( 1987) and Example 3 (.1988, 1989, and 1990). They were applied in amounts of 10, 15, 20, 25, 30, 35 and 40 kg/ha (exclusive of the binder).

The micronutrient fertilizer compositions uere applied along with Standard fercilizer compositions containing N, P, K and Mg as de-scribed below, with plots fertilized vich the Standard fertilizer 21 LV 10707 compositions but without the micronutrienc fertilizer composicions serving as concrol plots.

In 1987 and 1988, nitrogenous fertilizer was applied in an amount of 300 kg N per hectare, 270 kg in the form of urea (46X N) and 30 kg as calcium ammonium nitrace (27.62 N). In 1989, nitrogenous fertilizer was applied in the form of urea (270 kg N per hectare) and calcium nitrate (152 N, 30 kg/ha). The relatively large amount of nitrogen was applied in order to ensure that nitrogen was not the limiting factor for the growth of the plants.

The nitrogenous fertilizers were typically applied in > portions in February, May and June, respectively, with the calcium ammonium nitrate or calcium nitrate being applied in June. The micronutrient fertilizer composicions were applied in February together with the first portion of urea.

In 1990, 60 kg N/ha was applied in February as a mixture of diam-monium phosphate and calcium ammonium nitrate, together with the micronutrient fertilizer composition of Example 3. In April, 175 kg N/ha was applied as calcium ammonium nitrace.

In ali 4 years, the crops were furtherraore fertilized with 9 kg P/ha, 27 kg K/ha and 4 kg Mg/ha, the P, K and Mg being applied in February along with the micronutrient fertilizer composition and the first portion of nitrogen.

The time required for application of the micronutrient fertilizer composition together with the first portion of nitrogenous fertilizer was not significantly increased as compared to application of the nitrogenous fertilizer alone, since the micronutrient fertilizer composition in the form of pellets could be readily mixed and distri-buted with the nitrogenous fertilizer.

The folloving results (expressed as yield increase compared to the control plots, each number being an average for 4 plots, except for 1990) were obtained: 22

Micronutrient-containing fercilizer composicion applied (kg/ha) 10 15 20 25 30 35 40 Year Yield increase (hkg/ha) 1987 0.56 1.06 2.24 4.36 6.47 - 0.69 1988 0.42 2.34 4.26 2.99 1 . 72 2.62 3.51 1989 6.04 9.68 6.37 11.2 5.34 2.79 5.64 1990* 3.70 1.67 6.03 3.11 1.82 - - Average 2.68 3.69 4.73 5.41 3.84 2.70 3.21 (* The numbers for 1990 are averages for che follouing number of plocs: concrol, 3; 10 kg/ha, . 7; 15 kg/ha, 8; 20 kg/h a, 6; 25 kg/h 6; 30 kg/ha, 7)

The average yield in che concrol plots was 96.09 hkg/ha. 97.06 hkg/ha, 103.22 hkg/ha and 111.32 hkg/ha, respectively, for 1987, 1988, 1989 and 1990, which gives an average of 101.62 hkg/ha for che four years. 1c may be seen from che above table Chat che applicacion of che micronucrienc fercilizer compositions of che invencion in an amounc of from 10 co 40 kg/ha resulcs in an increase in yield which is of a significanc size compared Co the average yield of the concrol plocs.

Wheac samples from che plocs which had received che micronucrienc fercilizer composicions were analyzed for, among ocher chings, ash concenc. Ic was found chac che vheac had a relacively high ash con-cenc in che dry maccer (1.55Χ), indicaCing a high mineral concenc as a resulc of che absorpcion of che micronuCrienes in Che micronucrienc fercilizer composicion of che invencion. 23 LV 10707 EXAMPLE 6

ANALVSIS OF UHEAT FERTILIZED WITH THE MICRONUTRIENT FERTILIZER COMPOSITION OF THE INVENTION

Winter wheac fercilized with the micronutrient fertilizer composition 5 of Example 3 was analyzed for its concent of a number of different nutrients. The resulcs were corapared with Chose of winter wheat which was grown under the same conditions, but which were not fertilized with the micronutrient fertilizer composition.

The wheat crop was fertilized with 230 kg N/ha, of which about 60 0 kg/ha was applied in February (i.e. at the beginning of the growth season) along with 9 kg P/ha, 27 kg K/ha and 20 kg/ha of the micronutrient fertilizer composition, the remainder of the N being applied the end of April.

The results of nutrient analyses with and without the micronutrient fertilizer composition of the invention are shovn in the following (in which "+ micro" represents the vheat to which the micronutrient fertilizer composition was applied and micro" represents a control crop fertilized as above but vithout the micronutrient fertilizer composition): 24

Calculated nutrienc content in che crop (pr. ha)

Nucrient + micro - micro N 341 kg 307 kg K 367 kg 356 kg P 47 kg 32 kg s 28 kg 24 kg Ca 65 kg 38 kg Mg 17 kg 13 kg Fe 2687 g 3152 g B 53 g 60 g Mn 292 g 238 g Zn 244 g 193 g Cu 65 g 74 g Na 874 g 1313 g Si 32 kg 20 kg

Ic may be seen that che wheat which was fertilized wich the micro-nucrient fertilizer composition of che invencion contained an in-creased amounc of a number of different nutrients. In particular, a substancially increased amount of nicrogen was absorbed as compared to che control crop. In addition to che improvement provided to che crop icself, chis is an advantage from an environmental point of view, since che increased absorption of nitrogen will tend to reduce the amount of nitrate which may be leached out of the soil, thereby helping to reduce nitrate pollution of the ground water. 25 LV 10707 EXAMPLE 7

FIELD TRIALS COMPARING THE MICRONUTRIENT FERTILIZER COMPOSITION OF THE INVENTION WITH OTHER MICRONUTRIENT-CONTAINING FERTILIZERS

The advantageous effect of the micronutrient fertilizer composition of the invention as compared to certain other commercial micronutri-ent-containing fertilizers was shovm in field trials using vinter wheat.

The folloving micronutrient fertilizer treatments vere employed Amount used Name Nutrients in fertilizer (kg/ha) A: "Excello 2,65% Cu" Cu, Zn, Mg, Fe, Mo, Na, B 20 B: "Excello 5X ig Mg" Cu, Zn, Mg 20 C: "Mangandynger Jost" Mn, Fe, Zn, Cu 25 D: "Ollingsee Mikro"* N. P, K. Mg, Ca. Na, S. Cu, Μη, B, Zn, Mo, Co Fe, 40 E: Copper sulfate Cu, S 20 F: Desulphurizing product S. Ca, Mg, N 100 G: Control (no micronutrients) - * Micronutrient fertilizer composition according to the invention, corresponding to the composition of Example 3

The results of the field trials are given in the folloving table (the numbers being an average for 4 plots pr. treacment): 26 26 Relative yield

Yield increase compared to untreated Treatment (hkg/ha)

5 A 2 B 1 C 1 D 3 E ‘ 1 10 F 1 G 2 , 102 2 101 2 101 7 104 8 102 8 102 - 100 (LSD95 " 3·6>

The average yield for the untreated plots was 94.8 hkg/ha.

It may be seen from the above table that the micronutrient fertilizer 15 composition according to the invention provided a substantial yield increase not only compared to the untreated control, but also compared to the other micronutrient fertilizers tested. The micronutri-ent fertilizer composition of the invention ("Ollingsoe Mikro") was the only micronutrient fertilizer tested which gavē a statistically 20 significant yield increase (95Χ Ievel) compared to the control treat ment . 27 LV 10707

CLAIMS 1. A micronutrient fertilizer composition in the form of dry aggregate bodies, the fertilizer composition being adapted to be mixed with a macronutrient fertilizer composition, each aggregate body comprising salts of the metāls Cu, Mn and Zn, Cu being present in an amount of 1000-8000 g per 100 kg of the composition, exclusive gf any binder, Mn being present in an amount of 500-3000 g per 100 kg of the composition, exclusive of any binder, and Zn being present in an amount of 150-2500 g per 100 kg of the composition, exclusive of any binder, as well as at least one water-soluble nitrate which is not in the form of a salt of the above-mentioned metāls, each aggregate body comprising a substantially homogenous mixture of pārticies of the mētai salts and pārticies of the water-soluble nitrate. 2. A micronutrient fertilizer composition according to claim 1 wherein each aggregate body further contains a salt of Co and/or Mo in an amount of 5-100 g Co per 100 kg of the composition, exclusive of any binder, and/or 10-300 g Mo per 100 kg of the composition, exclusive of any binder. 3. A micronutrient fertilizer composition according to any one of claims 1-2 wherein each aggregate body further comprises at least one binder. 4. A micronutrient fertilizer composition according to claim 1 which contains Cu in an amount of 2000-5000 g per 100 kg of the composition, exclusive of any binder, Mn in an amount of 1000-2000 g per 100 kg of the composition, exclusive of any binder, Zn in an amount of 300-1500 g per 100 kg of the composition, exclusive of any binder, Co in an amount of 10-50 g per 100 kg of the composition, exclusive of any binder, and Mo in an amount of 20-150 g per 100 kg of the composition, exclusive of any binder. 28 5. A micronutrient fertilizer composition according to any one of claims 1-4 which comprises at least copper sulfate or copper oxychloride, manganese sulfate and zinc sulfate, and which comprises at least one compound selected from the group consisting of iron sulfate, Solubor® (soluble sodium borate, Na2BsOi3·4H20), borax, ammonium molybdate, sodium molybdate, cobalt sulfate, diamonium phosphate, potassium phosphate, potassium chloride, potassium sulfate and magnesium sulfate. 6. A solid fertilizer mixture comprising, as a first component, a solid micronutrient fertilizer composition according to any one of claims 1-5, and as a second component, a solid macronutrient fertilizer composition comprising at least N, P and/or K. 7. A method for fertilizing crops, the method comprising applying to the crops or to the soil a micronutrient fertilizer composition according to any one of claims 1-5 or a fertilizer mixture according to claim 6. 8. A method for preparing a micronutrient fertilizer composition in the form of dry aggregate bodies which are adapted to be mixed with a macronutrient fertilizer composition, the method comprising dry mixing without any substantial addition of water salts of the metāls Cu, Mn and Zn, as well as at least one water-soluble nitrate which is not in the form of a salt of said metāls, said salts and said nitrate being in the form of powders, to obtain an intimately mixed micronutrient mixture, and mixing the resulting micronutrient mixture with a binder to obtain said micronutrient fertilizer composition in the form of dry aggregate bodies in which each aggregate body comprises a substantially homogenous mixture of pārticies of the mētai salts and pārticies of the water-soluble nitrate, the amount of Cu being 1000-8000 g per 100 kg of the composition, exclusive of any binder, the amount of Mn being 500-3000 g per 100 kg of the composition, exclusive of any binder, and the amount of Zn being 150-2500 g per 100 kg of the composition, exclusive of any binder. 29 LV 10707 9. A method according to claim 8 wherein the micronutrient fertilizer mixture further contains a salt of Co and/or Mo in an amount of 5-100 g Co per 100 kg of the composition, exclusive of any binder, and/or 10-300 g Mo per 100 kg of the composition, exclusive of any binder. 10. A method according to claim 8 wherein the micronutrient fertilizer composition contains Cu in an amount of 2000-5000 g per 100 kg of the composition, exclusive of any binder, Mn in an amount of 1000-2000 g per 100 kg of the composition, exclusive of any binder, Zn in an amount of 300-1500 g per 100 kg of the composition, exclusive of any binder, Co in an amount of 10-50 g per 100 kg of the composition, exclusive of any binder, and Mo in an amount of 20-150 g per 100 kg of the composition, exclusive of any binder. 11. A method according to any one of claims 8-10 wherein the micronutrient fertilizer composition is prepared using at least copper sulfate or copper oxychloride, manganese sulfate and zinc sulfate, and which is prepared using at least one compound selected from the group consisting of iron sulfate, Solubor® (soluble sodium borate, Na2BaOi3·4H20), borax, ammonium molybdate, sodium molybdate, cobalt sulfate, diammonium phosphate, potassium phosphate, potassium chloride, potassium sulfate and magnesium sulfate.

Claims

EN 10707 COMPOSITION OF MICROMOSTIC INGREDIENTS PATENT FORMULA 1. The composition of the micro-fertilizer in the form of dry matter mass, suitable for mixing with the macromechanical composition, where each particle contains salts of metals Cu, Mn and Zn, with a Cu content of 1000 to 8000 g per 100 kg. containing no binder, the content of Mn is in the range 500 - 3000 g per 100 kg, excluding any binder, and the content of Zn is in the range of 150 - 2500 g per 100 kg, excluding any binder, as well as at least one water-soluble nitrate. not in the form of the aforesaid metal salt, wherein each particle contains substantially a homogeneous mixture of metal salt particles and water-soluble nitrate particles.

2. The composition of the micro fertilizer according to claim 1, wherein each particle of mass in addition contains Co and / or Mo salt in an amount of 5 -100 g Co per 100 kg, excluding any binder, and / or 10 - 300 g Mo per 100 kg composition without counting any binder.

A micro fertilizer composition according to any one of claims 1 to 2, wherein each particle in the mass further comprises at least one binder.

4. The composition of the micro fertilizer according to claim 1, comprising Cu in an amount of 2000 to 5000 g per 100 kg, excluding any binder, Mn in an amount of 1000 to 2000 g per 100 kg, excluding any binder, Zn in an amount of 300 to 1500 g per 100 kg, excluding any binder, Co in an amount of 10 to 50 g per 100 kg, excluding any binder, and Mo in a quantity of 20 to 150 g per 100 kg, excluding any binder.

5. The micro-fertilizer composition according to any one of claims 1 to 4, comprising at least copper sulphate or copper oxychloride, manganese sulphate and zinc sulphate, comprising at least one compound selected from the group consisting of iron sulphate, solubor (soluble) sodium borate, Na2B8013-4H20), borax, ammonium molybdate, sodium molybdate, cobalt 2 sulphate, diammonium phosphate, potassium phosphate, potassium chloride, potassium sulphate and magnesium sulphate.

6. A solid fertilizer mixture containing, as a first component, a solid microfiltration composition according to any one of claims 1 to 5 and containing as a second component a solid macromechanical composition comprising at least N, P and / or K.

7 / A method for fertilizing agricultural crops comprising the use of a micro fertilizer composition according to any one of claims 1 to 5 or a fertilizer mixture according to claim 6 for agricultural crops or soil.

8. A method for the preparation of a micro-fertilizer composition in the form of a dry paste suitable for blending with a macromate composition comprising essentially a mixture of salts of substantially non-aqueous metals Cu, Mn and Zn, and at least one water-soluble nitrate, other than the salts of said metals, in the dry state; wherein said salts and nitrate are in the form of powders to form a well-mixed microplastics mixture, and mixing of the resulting microfiltrate mixture with a binder to obtain said microplate composition in the form of a dry particulate mass containing substantially homogeneous particles of metal salts and water-soluble nitrate particles. a quantity of Cu 1000 - 8000 g per 100 kg, excluding any binder, the Mn content is 500 * 3000 g per 100 kg, excluding any binder, and the amount of Zn is 150 - 2500 g per 100 kg without counting no binder.

9. The method of claim 8, wherein the microfibre mixture further comprises Co and / or Mo salt in an amount of 5 to 100 g Co per 100 kg, excluding any binder, and / or 10 to 300 g Mo per 100 kg composition excluding no binder.

10. The method of claim 8, wherein the micro fertilizer composition comprises Cu in an amount of 2000 to 5000 g per 100 kg, excluding any binder, Mn in an amount of 1000 to 2000 g per 100 kg, excluding any binder, Zn in an amount of 300 to 1500 g per 100 kg, 3 LV 10707 not counting any binder, Co in an amount of 10 - 50 g per 100 kg, excluding any binder, and Mo in an amount of 20 - 150 g per 100 kg, excluding any binder.

11. A method according to any one of claims 8 to 10, wherein the microproposition composition is made using at least copper sulfate or copper oxychloride, manganese sulphate and zinc sulphate, and is produced using at least one compound selected from the group consisting of iron. sulfate, Solubor (soluble sodium borate, 10 Na2B8013-4H20), borax, ammonium molybdate, sodium molybdate, cobalt sulphate, diammonium phosphate, potassium phosphate, potassium chloride, potassium sulphate and magnesium sulphate.