Note: Descriptions are shown in the official language in which they were submitted.
W~95/0~23 ~26g ~ ~ ` PCr~N~93/00076
FERTILISERS COMPRISING ~ GAl~ ~HOSPHATE & PHOSPHATE
SOLUBILIS1:NG FUNGUS
TECHNICAL FIELD
The present invention is directed to fertilisers. More specifically, the present invention is
5 directed to enhancing phosphate solubilisation by the action of fungal and/or microbial
action. A preferred embodiment of the invention comprises suitable fungus, ~ucro-
organisms or reproductive materials therefor combined with a mineral substrate.
Typically the rnineral substrate comprises a phosphate material. In many embodiments a
suitable nutrient is included.
10 BAcKGRouND-ART
Phosphorus, one of the main trace elements, is generally added to pasture in the form of
superphosphate, an acidified form of rock phosphate. Compared with normal rock
phosphate, which is generally and predominantly calciurn phosphate, superphosphate is
much more soluble and is available to plants relatively quickly.
15 Rock phosphate is still used in the fertiliser industry for application to pasture,
particularly where the more rapid release of the superphosphate is not required, or where
a long term slow release of plant phosphorus may be preferred. Economics also comes
into play as rock phosphate needs only to be milled whereas superphosphate requires, in
addition, treatment of the raw phosphate material with acid. Over a large area, cost
20 differences can become significant. During lean times many farmers may be faced with a
choice of spreading more expensive superphosphate, c~eaper rock phosphate (which may
not be suitable for the particular application) or not fertilising with a phosphorus
containing material at all. Furthermore, the acidic nature of superphosphate often
requires limung if the norrnal soil pH is to be maintained, this being an additional cost
25 factor.
A growing trend towards the use of naturally occurring fertilisers is also occurring.
There are relatively fe~w natural fertilisers, with the possible exception of fish based
compositions, which are high in phosphoNs. However these may over supply other
elements in addressing a phosphorus deficiency. Rock phosphate, in contrast, lacks the
30 faster release characteristics of superphosphate or the fish based composition.
Further, there are many micro-organisms and fungi, many of which occur naturally in
many soils, which are advantageous to have in pasture as enhancing or encouraging plant
growth. Some of these assist the plant in taking nutrients from the soil while many
others are able to assist the release of nutrients, otherwise bound up, to be available to
35 plant life. While many of these are known, not all are present in all soils and quite oRen
only appear as a result of introduction through stoc~- and agricultural equipment from an
wo gs/06623 2 1~ 8 2 6 9 ~ PCIINZ93J00076 ~ ' ~
infected location. While son~e bene-fi~ lrrfay be gained through the introduction of such
'helpful' life forms, there appèars to be no generally available method allowing the
average farmer to introduce them i.e. it is not simply a case of sprinkling seeds or spores
over a paddoek.
5 One method which has been used is to treat seeds with bacteria inocula prior to planting.
However this is not applicable for existing pasture? and also makes the end userdependent upon the availability of such inoculated seeds. Furthermore, inoculants are
typically localised to the area of the plant's roots where it will not come into contact with
insoluble phosphate materials which may be applied to the top of the soil. Instead, what
10 would be preferable is an agent able to act directly on the phosphate material to enable the
nutrients to leach into the soil for plant use.
Quite clearly there is a need for a product which can address the foregoing problems. It
is therefore an object of the present invention to address these problems or at least to
provide the public with a useful choice.
15 Further aspects and advantages of the present invention will become apparent from the
ensuing description which is given by way of example only.
DISCLOSURE OF INVENTION
Accor&g to one aspect of the present invention there is provided a fertiliser composition
comprising:
20 - a mineral substrate including a phosphate matedal,
- an introduced fungus, rnicro-organism or repro~ctive material therefor, and
- a nutrient for supporting or establishing an introduced fungus, micro-organism or
produc~ive material.
According to another aspect of the present invention there is provided a fertiliser
25 composition, substantially as described above, which includes at least one member or
reproductive material therefor, of a group comprising:
Fusarium oxysporum, Fusarium solani, Aspergillus Niger, Aspergillus candidus,
Aspergillus flavus, Aspergillus ustus, Penicillium janthinellum, Penicillium sp..
Sclerotium rolfsii, Cylindrocladium sp., Trichoderma viride, Glocladium sp.,
30 Verticillum albo-atrum, Penicillum bilaji, Mortierella nana, Mortierella longicollis and
Aspergillus terrens.
According to another aspect of the present invention there is provided a method for the
preparation of a fertiliser composition comprising the introduction of a nutrient, and a
fungus, micro-organism, or reproductive material therefor, to a mineral substrate
35 comprising a phosphate material.
~=,a~! W095/066~3 21l8269 PCI/NZ93/00076
According to another aspect of the present invention there is provided a method for the
preparation of a fertiliser composition substantially as described herein with reference to
the contained examples.
According to another aspect of the present invention there is provided a fertiliser
S composition comprising, by weight to a total of 100%:
- E;tock phosphate or insoluble phosphate 5-99.999
- Introduced fungus, micro-organism or
reproductive material therefor trace - 5%
- Nutnent 0-95%
- Non-phosphate mineral substrate 0-95%
According to another aspect of the present invention there is provided a method for
increasing the solubilisation of phosphate fertiliser materials comprising the introduction
of a nutrient, and phosphate solubilising fungus, micro-organisms or reproductive
- material therefor to said phosphate fertiliser materials prior to their application to soil or
15 pasture.
According to another aspect of the present invention there is provided a method for
increasing the availability of phosphorus for plants comprising the application to soil or
pasture of a composition comprising a phosphate fertiliser material, a phosphate- solubilising fungus, micro-organisms or reproductive material therefor, and a nutrient
20 capable of sustaining, supporting or establishing the growth of same.
Embodiments of the present invention will typically comprise a mineral substrate. The
rnineral substrate serves to act as a base to which biologically active material (i.e. fungus,
rnicro-organism (including microbes) andtor reproductive material therefor) can be
introduced. As typically the action of the biologically active material is to improve
25 phosphate solubilisation and release into the soil, the rnineral substrate will normally
comprise a phosphate material. While virtually any phosphate material may be used, it
will typically comprise an insoluble phosphate in preference to more soluble forms such
as 'super phosphate'. A good example of the insoluble phosphates include the so-called
'rock phosphates', some specific examples of which are the North Caroliha rock
30 phosphates (NCRP), Peruvian rock phosphates (available in New Zealand under the
name SECURAROCK ~), or the Egyptian rock phosphates ~marketed in New Zealand
under the name QUINPHOSTM). However, it should be appreciated that other forms of
rock, and insoluble, phosphates exist which may be used within the present invention,
though it is considered that phosphate materials commercially exploited for fertiliser
35 application will usually be selected. It is also noted that phosphate materials present in
the mineral substrate need not be restricted to the generally less expensive insoluble
forms.
wo ss/06623 ~ 1 g ~ P~ r~zs3/o~n76
The mineral substrate may solely comprise one or more rock or insoluble phosphate
materials. However, in other embodiments, additional constituen~s may be present.
These may be present as discrete particles in a composition or incorporated into more
sophisticated 'pellet' type forrns, to be discussed herein.
5 Typically the rnineral substrate will comprise a solid granule or pellet through may also
c.omprise substan~ially a powdered material. In most cases the average particle size will
not exceed 10mm as larger material is not readily spread by most commercial equipment
and large fragments may be a hindrance to farming. As, to some extent, nutrient and
rnineral release (per weight of binding material) is dependent upon particle size
10 (powdered forms generally having a faster release), particle size can be used to help
govern the release characteristics of the product.
The substrate may comprise many materials though will often be substantially mineral in
nature. The substrate may comprise naturally occurring materials, such as rock
phosphate, broken where necessary to an appropriate size. Alternatively, it may
15 comprise a reconstituted conglomerate or pellet of, substantially, mineral constituents.
However, the various embodiments will almost invariably include a phosphate material
and may, for exarnple, comprise powdered rock phosphate pressed into a pellet form of a
uniforrn size.
By way of exarnple, additional mineral constituents may comprise an aluminosilicate,
20 which te~n wherever used herein shall often refer to an aluminosilicate clay. There are
many such materials known and include, by way of example only, verrniculite, bentonite
(montmorillonite), sepiolite-attapulgite, illite, chlor~te, halloysite and kaolinite. One
preferred aluminosilicate for use in the present invention is bentonite which is readily
available. Bentonite generally refers to a clay comprising more than 70%
25 montmorillonite.
If the process allows, it may be desirable to incorporate alternative or additional mineral
constituents into the pellet. These may be, for example, lime, clays, zeolites or various
minerals. These may act as nutrients for the micro-organisms or fungi, or comprise plant
available nutrients to be eventually released to a plant. They may modify the physical
30 characteristics of the pellet, such as by helping cement the pellet together, or adjusting the
porosity which can affect how well a pellet may be impregnated or how quickly it'releases' its contents after application to pasture.
As can be appreciated, the mineral substrate will generally act as a support for any
biologically active material. Where substantially non-processed materials, such as
35 untreated insoluble phosphate, are used the available options may be limited. However,
there is room for great variation in the nature of a product if one or more constituents are
wo sslo6623 214 8 2~ ~ PCT/I~Z93/00076
broken down and re-combined to form a rnineral substrate. As can be appreciated,parameters such as the porosity9 fertiliser elemental content, particle size and other
variables can be rigidly controlled and almost in~lnitely varied. However it will also be
appreciated that this will increase the number of manufacturing steps and thus, the cost of
5 the end product.
The reconstitution of blended materials can also allow for the introduction of biologically
active material in a substantially dry form and also may more readily allow for its even
distribution throughout the product. The addition of liquid forms may be used to initiate
setting or cementing of particles or pellets.
10 As can be appreciated there are many possible combinations which allow a pellet having a
wide range of physical or practical characteristics to be obtained. It shall be assumed that
a reader skilled in the art will be able to select components suitable for their needs and
combine them into a suitable pellet. Similarly the manufacture of bound or pressed
- pellets is well known and the many possible techniques will not be described herein.
15 Another constituent which may be included in a fertiliser composition, and which may be
present as part of the rnineral substrate or added subsequently, is a hydrating agent.
Some non-reversible hydrating agents have been mentioned already and these include
unslak~d limes, calcium sulphate, gypsum and other cementing type constituents. These
may be included to help cement particles or granules together, or to absorb excess
20 moisture such as from a liquid nutrient (if added) or a fluid media for the introduction of
biologically active material. The effect in this case will absorb the added moisture so that
the end product is still a substantially dry, flowable mat rial.
Other hvdrating agents are known and these may not necessarily be binding or cementing
type materials. For instance, calcium chloride and various silica gels `are among other
25 well known hydrating agents (the term 'hydrating agent' or 'hydrating constituent' being
used to indicate a substance capable of absorbing or adsorbing moisture). Zeolite
matenals may also be used as hydrating agents.
Also of use are what shall be termed as reversible hydrating agents, in which water taken
in is available for use by the biologically active material. Useful in this regard are many
30 gels such as gelàtine and agars though many more are also known. One fish based
fertiliser, suitable for use as a nutrient in the present invention, includes seaweed whose
proportion can be varied during manufacture to alter the viscosity of the resulting
product. This product is available in Australasia from Moana Fertilisers Limited or
Sieber Agricultural Lim~ted of Waiuku, New Zealand.
35 Another substance of use are the newer cross-linked polymers, some of which are
biodegradable (usually after a period of several years). Some of these have been recently
O 95106623 2 1 4 8 2;6 9 PCI`/NZ93/00076
r f
put to use in potting mixes arid the applicant is aware of at least one product available in
Australia under the trade name of AGRosoKETM.
Hydrating agents and constituents may be employed in the present invention to not only
- to absorb excess moisture so that a substantially dry product results or to act as a
5 cementable binder, but also to sustain the life of added biologically active material. This
can then be used to usefully extend the bulk storage life of the fertiliser composition
according to the present invention.
Many embodiments of the present invention will also include a nutrient. Typically this
will be a nutrient useful to the introduced biologically active material. Typically these will
10 also be plant useful nutrients and thus a duai purpose may be provided - there is a
nutrient suitable for sustaining introduced biological material, and there is a means for
altering the NPKS characteristics of the fertiliser which can extend the range of
applicability for the end product as a fertiliser.
A nutrient may comprise materials cornmonly used as plant fertilisers and the invention
15 represents an alternative means of preparing a high phosphorus, multi-elemental fertiliser.
Often these 'normal fertilisers' will also enhance the growth of the contained fungi and
micro-organisms though nutrient blends more specific to the particular targeted or
included organism may be used. In most cases a nutrient acting as a nitrogen source is
suffisient but should not be in such a high or readily available concentration as to
20 adversely affect any targeted or included organisms.
While many nitrogen providing nutrient sources may be used, some preferred
embodiments of the present invention make use of nutrients containing ammonium
compounds or amines. Many ammonium and amine based fertilisers are known and maybe employed. However, it is noted that many fish based fertilisers are also rich in amines
25 and, depending on the production process, a typical ammoniacal smell can often be
detected. Typically the use of ammonium, and arnine containing, nutrients will be
beneficial as recent research by others have suggested that the nitrification of free
arrlmonia may increase the solubility of North Carolina phosphate rock~ This research
(published in Compost Science and Utilisation, Premier Issue, 1993) supports the30 applicant's observations in trials that the use of a fish based fertiliser product on
phosphate rock noticeably increased its solubility and, therefore, availability for plants.
In some instances a significant ammoniacal smell was detected after fungal growth had
been established. The use of nutrients able to be readily converted into free ammonia for
subsequent nitrification processes may be especially useful in some embodiments, and
3c rnay be a means by which the rate of release of phosphorous from the insoluble
phosphate can be varied.
w095/06~23 21~$'~69'~" PcTlNz93/00076
The aforementioned fish based ~ertiliser product, based on the acid and (optionally) base
hydrolysis of marine matter, has been found to be effective in trials. Granular mineral
binding material impregnated with the fish fertiliser was found to support the growth of
fungal and plant matter after a relatively short period though this will depend upon a
S number of factors such as temperature and seasonal variations, the presence of fungus or
micro-organisms in the soil, moisture content and rainfall etc. It is anticipated that
equivalent products may also be successfully used as a nutrient.
Another usefui nutrient, other than those already described, can include the typical liquid
waste from many meat processing plants, which is often rich in animal protein. Animal
10 protein is a useful nutrient source for many biologically active materials which may be
introduced.
To improve the efficiency of ammonia release, if this avenue is to exploited, biological
material readily able to convert available nutrients into free ammonia may be included
- within the composition. Biological material associated with the subsequent nitrification
15 of free ammonia may also be included.
Nutrients may be introduced to the mineral substrate in a variety of manners. For
instance if provided in a dry forrn, they may be dusted or coated onto the mineral
substrate. Where the mineral substrate exists in a substantially powered or granular
form, dry nutrients may merely be blended in to the mixture. In embodiments where
20 pellets are manufactured, rather than relying on natural granules of a substance, it may be
possible to use 'dry' nutrients.
Where the mineral substrate is present in larger lumps ~hough this may also be applied to
other embodiments) it may be easier to apply a liquid based nutrient which can be used to
impregnate the particles. This may comprise making an aqueous solution of the desired
25 nutrients though many nutrients may already come in a liquid form able to be directly
applied. In this case the granule or pellet should be porous to the solvent chosen. A
greater degree of control over porosity is possible for manufactured pellets though most
rock phosphate and other minerals are porous to, and will absorb, ~vater and common
solvents.
30 A nutrient, where provided, can be a useful carrier for introducing biological rnaterial to
the mineral substrate: This may merely comprise dispersing a suitable source of the
active material into the nutrient (preferably a liquid form) prior to its introduction to the
mineral substrate. In some cases, the biological material may even be cultured in the
nutrients prior to its introduction to the mineral substrate.
35 A range of suitable biological materials are available. Preferred amongst the introduced
biological material are those which are phosphate solubilising i.e. are recognised for
'''i
wo 9S/06623 2 14 8 2 ~ L ~ ~ r /~
freeing phosphorous from insoluble phosphate materials. Also preferred are those which
have been previously mentioned. such as those able to liberate free arnmonia from added
nutrients or nutrients present in th~o soil, and those associated with the nitrifica~ion of free
ammonia. These are well known within the field.
5 Both fungus and microbes are considered to be useful in the present invention and it is
possible that a combination of, or more than one of, each group rnay be employed in the
present invention. It is also considered that some of these useful biological materials rnay
already be present in certain nutrients though it is likely that they will be cultured to an
acceptable level before being incorporated into the present invention. It is also possible
10 that growth and reproduction may continue while the product is stored prior to application
and this may be taken into account in the production of a fertiliser composition according
to the present invention. In some instances it may be desirable to store the substantially
completed product for a given period of time in order for certain biological materials
present to establish themselves to a desired level.
15 Useful fungi for use in the present invention include member of the species Aspergillus,
Fusarium and Penicillium. Most members of these fungal groups are useful though in
particular the following may be considered: -
Fusarium Oxysporum, Fusarium Solani, Aspergillus Niger, Aspergillus Candidus,
Aspergillus Flavus, Aspergillus Ustus, Penicillium Janthinellum, Penicillium sp.,
20 Sclerotium Rolfsii, Cylindrocladium sp., Trichoderma viride, Glocladium sp.,
Verticillum albo-atrum, Penicillum bilaji, Mortierella nana, Mor~ierella longicollis and
Aspergillus terrens. 4
Some other micro-organisms of use in the present invention include Bacillus
Megatherium phosphaticum and strains thereof, Gram-positive bacteria and members of
25 the species Pseudomonas.
Aspergillus niger, and Sclerotium rolfsii are considered as more desirable members of the
list, whereas members of the genus Rhizoctonia and Pythium are considered to be only
minimally, if at all, effective. However it is to be noted that the foregoing lists are not
meant to be exhaustive but are provided by way of example only. It is noted that not all
30 members of named species may always be useful in all embodiments and thus some
experimentation for various embodiments may be recommended when implementing
some of the large number of variations possible within the scope of the prescnt invention.
As an alternative for the introduction of the living organisms, reproductive material able
to establish into the desired biological material may also be provided. Fungal spores,
35 where able to be collected, may also be introduced into a fertiliser composition and in
some cases this may be useful for extending the shelf li~e of fertiliser compositions.
~ wo gs/06623 2 1 4 8 2 6 9 ` ~ 7 ' PCT/I~i~g3/~0076
However this is generally dependent upon the conditions of storage being chosen which
is conducive to the existence of the spore or reproductive material, yet will not
prematurely encourage their growth while in storage.
As previously men ioned, the introduction of the nutrient and/or a culture material to the
5 binder material may be by impregnation. While either or both these components may be
incorporated during formation of a pellet, they may also added by allowing the liquid to
soak into the substrate material. The liquid may be applied by spray, dipping or mixin,,
of dry and wet material. However, too high a concentration of nutrients in the liquid
nutrient mixture may best be avoided unless the impregnation method allows for the
lQ relatively even distribution of the liquid rnaterial to the dry.
Various other modifications may be made to a fertiliser composition according to the
present invention. For instance, biological material may be introduced in a coating to the
particles of the composition. This may comprise a gelled layer, which could also include
the nutrient. A thickened seaweed and fish based fertiliser is available upon request from
15 Moana Fertilisers Limited or Sieber Agricultural Lirnited of Waiuku, New Zealand. In
this case an increased proportion of seaweed gels the fish fertiliser.
Alternatively the coating may be nutrient free, and nutrients ~if provided) being
introduced into the particles or mineral substrate.
Alternatively the coating may be free of biological rnaterial, which is introduced into the
20 substrate. The coating may help preserve moisture content and act as a barrier.
The coating may swell when wetted (in the field) or o~therwise 'release' or allow fungus
within the particle (or coating~ to begin to grow. A hydrating cross linking polymer may
be used. In these embodiments the coating may act also as a semi-protective wrapper
signalling when biological growth is to occur.
25 As another example of modifications, the nature of the composition will effect how it may
be used and applied. Typically it is preferred that the end product is a substantially dry
flowable material as this would enable its application by relatively common dry material
spreaders. In many cases the available equipment will still manage a damp product
though it is still generally desirable that the composition is able to flow. The use of
30 hydrating agents and constituents has been described to absorb excess moisture which
may be added during various stages of production. However it is also noted that a
distinction is to be made with hygroscopic and deliquescent materials which could
continue absorbing moisture from the atmosphere and result in a 'wet' product.
Consequently, where possible, the use of hygroscopic or deliquescent materials should
35 be eliminated or reduced.
WO 95/06623 2 1 ~ 8 2 6 9 PCr/NZ93/00076 ~
A modification which may be incorporated into the invention is to coat, impregnate or
o~herwise treat particles with an agent able to promote their free flowing. Many dusting
agents such as talc, various stearates etc could be used in this regard. Some of these may
also be partially water repellent which can be useful in preventing further absorption of
5 water by the particles. In addition it may also help reduce moisture lost by the particles
which can be useful for sustaining biological material present. However a coating agent
which will be readily removed after application o~ the fertiliser cornposition is generally
preferred unless a slow or delayed release product is desired. The use of separate
constituents which reduce moisture loss (and which need not necessarily comprise a free
10 flowing agent) may also be applied.
The particle size is a matter of user choice and will also be influenced by the method of
manufacture. It is envisaged that most embodiments of the present invention will have an
average particle size such that at least 90% will be able to pass though a sieve with a mesh
size of 10rnm by 10rnm. This would be regarded as a coarse embodiment and may not
15 find universal application. Probably more useful is a finer grade in which 90% of the
particles will pass through a sieve with a rectangular mesh of 3mm by 3mrn. In ultra fine
embodiments, the composition may be substantially powdered.
Further aspects and advantages of the invention will become apparent from the ensuing
- examples, which are not intended to be restrictive but to illustrate but some aspects of the
20 present invention.
BEST M~DES F~R CARRYING OUT THE INVENTION
Example 1 '~
A nutrient broth comprising a suitable fungus and micro-organism is prepared andmaintained. This could be, for instance, a fungus of the genus Fusarium though need not
25 be restricted to this alone. Other biological materials have been described previously.
Standard biology techniques for growing and maintaining cultures may be followed.
From this parent broth is drawn off fractions to be used in preparation of a product.
The nutrients present in the broth may be according to that used in standard biological
growth procedures though ~vill most likely comprise a nitrogen source. The broth may
30 also be an aqueous solution of ammonium or another nitrate. Early trials have also
shown some success with aqueous fertiliser compositions derived from fish and marine
matter. The greater range of nutrients here would tend to provide an improved product
for use as a fertiliser.
The substrate in this example is a commercially available rock phosphate broken down to
35 an accep~able size. An average size of 3mm or less is considered to be useful, though
this is a matter of user choice.
~ Wo 9~/06623 2 1 1 8 2 6 9 PCT/I`IZ93100076
To the substrate is added, in an aqueous form, the nutrient/culture mixture which is
absorbed into the rock phosphate to impregnate it. A ribbon blender/mixer may be used
to mix components. The fluid components are typically added slowly or sprayed into the
rnLxing vat.
5 While virtually any ratio of substrate:liquid may be used, it is preiferable to use lower
quantities of liquid if a substantially dry product is to be obta~ned. While slurries or
suspensions of substrate may be used and are within the scope of the present invention, it
is envisaged that these liquid forms are more suitable for application of the invention
rather than as a form which may be stored for some time before application. If
10 necessary, substantially dry folms may be converted into a slurry or liquid form prior to
application.
In trials, less than 25% (by weight) liquid was added to the substrate, with around 10%
being preferred for obtaining a substantially dry product. Once impregnated, the product
may be dried though considerations include the extra time and cost for drying and the
15 effect of excess drying on the included fungus or micro-Qrganism. It is envisaged that in
most, but not all, cases the product will have a free moisture content ~by weight) of less
than 25% and more likely 5-15% inclusive. By free moisture is meant water not present
as waters of crystallisation of various components. The use of components able to
remove excess water through crystallisation, or through a physical (eg. zeolites) or
20 chernical reaction (eg. gypsum, calcium sulphate monohydrate, unslaked lime etc.), may
also be used to create a product having the preferred water content and allow the addition
of more dilute nutrient solutions during impregnation but still provide a substantially dry
product.
Example 2
25 Here the product substrate comprises a manufactured pellet. By way of example it may
contain the following constituents:
Component % by weight [to total of 100%]
gypsum up to 95%
lime j up to 95%
aluminosilicate up to 95%
roek phosphate 5% to 100%
a fertiliser or mixture
containing nitrogen and/or potassium
and/or trace elements up to 90%
rnineral or vegetable or other oil up to 15%
water up to 25%
11
Z14~
W 0 95~0 6 62 3 p CI'INZ93/0007 6 ~
,,, . ~ `, . .. . .
~ . . V
biological material comprising fungus,
micro-organisms and/or reproductive material 0-5% (typical)
Various aluminosilicates may be used and the term includes within its ambit clays such as
kaolinite, bentonite, etc., and zeolites of which many are commercially available.
S The added fertilisers generally comprise inorganic fertilisers generally include m~neral and
synthetic products, including various nitrates, phosphates, sulphates, chlorides etc.
Materials based on organic materials such as plant or animal matter may be used, but
these shall not fall within the terrn 'inorganic'.
The weight of the included biologicaI material is typically only that of the material, not
10 including any culture or growth medium, which may comprise an additional constituent
of the product. A relatively porous pellet is obtained which is impregnated with a
nutrient/culture mixture (if not incorporated into the manufactured substrate) in the sarne
manner as example 1.
Example 3
1$ This comprises a manufactured pellet as described in example 2 but wherein culture
medium (comprising the fungus or micro-organism) is blended substantially
homogeneously with the pellet components before pellet forrnation.
Nutrients, especially if not present in the binder materials, may be incorporated into the
pellets by liquid irnpregnation, if at all.
20 Example 4
As for exarnple 3 but wherein nutrient is blended into tRe pellet prior to its formation and
the culture medium introduced through liquid irnpregnation after pellet forrnation.
Exarnple 5
Here the product comprises either a manufactured pellet or bland of components which
25 may be substantially particulate or powdered in form. The constituents are as follows:
Component % by weight [to total of 100%]
rock or insoluble phosphate 35-80%
bentonite or bentonite predominant
aluminosilieate 20-65%
fungus, micro-organisms andlor
reproductive material trace-5%
liquid nutrients comprising at least one of an
arnmonium and/or arnine containing nutrient, a
fish based composition, and an animal
protein based composition 0-15%
12
~ WO 95/06623 2 1 l 8 2 fi ~ PCr/NZ93/00076
Exarnple 6
A fertiliser composition which comprises, by weight to a total of 100%:
- Rock phosphate or insoluble phosphate 5-99.9g9%
- Introduced fungus, micro-organism or
reproductive material therefor 5%
- Nutrient 0 95%
- Non-phosphate mineral substrate 0-95
Example 7
As for example 5 in which the micro-organism, fungus (or reproductive material
10 therefore) is phosphate solubilising.
- Example 8
As for examples 6 and 7 in which the nutrient chosen is a liquid fish based fertiliser. A
suitable product is that available from Moana Fertilisers Limited or Sieber Agricultural
Limited of Waiuku, New Zealand, or the equivalent thereof. Manufacturer's data and
15 specif~cations are available from the applicants.
Exam~le 9
As for examples S through 8 in which a substantially reversible hydrating constituent is
included. This may comprise the use of a gel such as agar though may also comprise the
use of a seaweed-fish based fertiliser such as that available from Moana Fertilisers
20 Limited or Sieber Agricultural Limited of Waiuku3,New Zealand, or an equivalent
product. Another option is the use of the product AGROSOKErM.
Exarnple 10
This embodiment comprises a coated pellet in which the coating is a gel-like covering
suitable for the rapid establishment and growth of contained biological material.
25 Preferably this embodiment is directed to pelleted type embodiments where'any one
particle substantially comprises a substantially homogeneous blend of components.
However, it could also be applied to non-pelleted rnixtures, in which case it is preferred
that the constituents are sùbstantially non-powdered and preferably also not the larger or
coarser sizes. It is envisaged that particle or pellet sizes which fall predominantly within
30 the average size range of 2-5mm diameter will be most applicable for this particular
embodiment though it is noted that a larger size could be tolerated for substantially
homogeneous pallets.
The method comprises'the application of a suitably viscous coating to particles. These
particles could be any of the products from the previous examples, though with the above
13
WO 9S/06623 2 1 ~8 2~ 9 PCT/NZ93/00076 ~
recommendations in mind. The naturç o~f the coating is typically that of a gel and it is
preferable that a gel which will further harden, perhaps via a setting reaction, or through
the loss of water, is used. Typically the gelled coating will be applied while still in a fluid
or semi-fluid state, though will eventually form a discrete coating on each particle which
S will not clog or bind par~icles together into a sticky mass.
Several methods may be used to achieve this. For instance, many gelling materials such
as agar and gelatine (among other examples), have a setting reaction. Conseguently,
these type of gelling agents may be used for the coating and applied before the setting
reaction has climaxed.
10 As an alternative, moisture absorben't materials or hydrating agents within the particle
could promote the formation of a suitable coating.
As a further modification, a free flow agent could be dusted or applied to the resulting
coated particles to reduce the further possibility of particles sticking or binding to each
- other in the bulk form.
15 The coating may comprise a nutrient, such as the liquid fish based fertilisers available
from Moana Fertiliser Limited. Other liquid nutrients could also be used, or a solution of
solid nu~rients. The use of a thicker seaweed based ~lsh composition from Moana
Fertiliser is also possible though additional gelling agents may be added prior to its
application. If the coating of interest is sufficiently fluid, then rather than a discrete
2û coating on the particle, the outer surface layers may impregnated so that an outer crust
comprising par~ of the intended coating and part of the substrate may be forrned. In some
instances this can be just as effective as a discrete gelle~ coating.
Also likely to be included within the coating are the biologically active material as the
coating is generally intended for use as a support for the rapid establishment of the
25 biological material. However in some embodiments, the biological material may be
applied to the substrate and under the coating. In this case the coating may also act as a
protective layer for the material during storage. Each variation has its own inherent
advantages and disadvantages, which the manufacturer can select as desired.
Application of the coating may be via a number of known methods, including a ribbon
30 blender. However to some extent the method of coating will depend upon the viscosity
and proportions of components.
Exam~21~11
This embodiment comprises rock phosphate material, typically of a size able to pass
through a 10mm screen. Also present is other solid material which may comprise
35 manufactured pellets such as from previous examples acting as a biological base for the
14
WO 9511)66~3 2 1 g 8 2 6 9 PCI/NZ~3/00076
establishment of contained active or reproductive material. The solid material, which may
take the role of a filler or diluent for the phosphate material in the product, can also
include other substantially mineral materials such as previously mentioned (e.g.aluminosilicates, clays, zeolites, gypsum, limes etc.).
5 The resul~ing mixture may be impregnated with a nutrient, which may also introduce
biologically active material, especially if these components are not present in the included
solid material. The rnixture may also be further processed according to techniques
detailed in the preceding exarnples and description.
Nature of product.
10 In most c.ases the product will comprise a pellet or granule with a relatively low moisture
content (25% or less and preferably 5-15%). The average particle size will often be
lOmm or less, and more preferably 3mrn or less. Finely powdered forms may also be
used though typically the products will be granular in size, e.g. similar to coarse sand.
- This makes impregnation and rnixing with liquid components easier.
15 The pellet of most embodiments will comprise essentially a substrate incorporating
nutrients and a culture able to establish a growth of selected fungi and/or micro-
organisms. These will normally remain relatively dormant while the product is in its
preferred, relatively dry state. Some organisms may be better adapted than others for
storage and many may have optimum storage conditions, which information is either
20 known or may be found through relatively simple trial and experimentation.
Typically the product will be porous as many embodiments rely upon liquid impregnation
to introduce some of the components. Porosity also allows the product to be 'activated'
when wetted or rained upon. Porosity also influences how rapidly the product decays or
releases its contents.
25 The product also represents a means of preparing a solid or 'dry' fertilising composition
from a liquid fertiliser. This may in practice provide advantage as many fertilisers are
transported in a dry form and consequently a large amount of equipment is adapted for
dry or solid material. At least one embodiment of a product also represents a high
phosphorus fertiliser which also contains other nutrients, according to the impregnated
30 components. Phosphates are generally applied on their own or with lime - the present
invention represents a means by which additional elements and useful micro-
organisms/fungi can be applied during the same operation and perhaps without thenecessi~f of separate liming.
Also, the nutrients will often tend to be released at a relatively slow rate, at least
35 compared to a liquid fertiliser applied to pasture. This may be advantageous in areas of
high rainfall where many liquid and some readily soluble solid fertilisers would be
16
Wo 95/06623 21~ 8 ~ B 9 ` PCr/r~Zs3l00076
.
quickly washed from the soil. The rate of establishment of the fungus or other preferred
micro-organisrns may further regulate rapid leaching of nutrients frorn the product.
In practice, the product may be also used in many (but not every instance) as a method of
packaging fungus or micro-organisms in a relatively dormant or transportable state.
5 Providing that storage, manufacture and product use are within acceptable lirnits for the
particular organism, the product may be used to initiate the growth of new colonies of the
organism.
While a primary use is as a fertilising composition, where new and useful organisms may
be introduced or supplemented into field and pasture, the invention may find other use.
- 10 For instance it is suitable for the 'package' and transport of laboratory cultures. It may
find use in culture depositories. It may also find use as a pharmaceutical device or
feedstuff for animals. In such cases nutrients may be suited more towards the animal
(e.g. minerals and vitamins) while the culture could be an organism which aids digestion
(for instance by including micro-organisms present in the digestive system or which can
15 improve the digestion of some materials), or which produces a useful enzyme, or which
acts as an antibiotic. It is anticipated that a skilled reader, in light of the description
herein, would be able to readily adapt the present invention for use in these other areas.
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
20 departing from the scope thereof as defined in the appended claims.
16
