Field of the invention:
The present invention relates to an eco-friendly, stable formulation of mineral oil and sulfur
having a superior insecticidal efficacy and low phytotoxicity. More particularly, the present
invention relates to an eco-friendly, stable formulation of mineral oil in combination with a
suspension concentrate of sulfur and processes for preparation thereof.
Background and Prior art:
The challenge involved in developing commercially acceptable products containing
agriculturally active compounds in combination continues to increase due to the rapid
emergence of more complex customer and regulatory requirements. These agricultural
compositions must exhibit excellent chemical stability and must also maintain a high level of
physical stability under a severe range of storage and use conditions especially when used
in combination.
Sulfur is the chemical element with atomic number 16. In the periodic table, it is represented
by the symbol S. It is an abundant, multivalent non-metal. Under normal conditions, sulfur
atoms form cyclic octatomic molecules with chemical formula S8. At room temperature
elemental sulfur is a bright yellow crystalline solid. Chemically, sulfur can react as either an
oxidizing or reducing agent. It oxidizes most metals and several nonmetals, including
carbon, which leads to its negative charge in most organosulfur compounds, but it reduces
several strong oxidants, such as oxygen and fluorine. It is also the lightest element to easily
produce stable exceptions to the octet rule.
Sulfur is one of the oldest pesticides known, also widely used today as a pesticide for the
control of powdery mildews, rusts, leaf blights and fruit rots (Agrios, G. N., Plant Pathology,
4th edition, p. 208). Sulfur disrupts the metabolic processes of fungi and protects plants from
diseases by inhibiting spore germination (Ellis, B. W. and F. Marshall Bradley, eds., Natural
Insect and Disease Control, p. 369). Sulfur is also sometimes used as a miticide. For
example, Kumulus D F, a water dispersible granular fungicide, is an approved pesticide for
use against rust mites. Traditionally some plant diseases were controlled with applications of
elemental sulfur, but this necessitates frequent, high volume applications of an irritating
material. Sulfur causes plant injury in hot and dry weather conditions.
3
However, sulfur is difficult to formulate into a formulation either alone or in combination.
Problems associated with sulfur formulations include formation of unsightly residue on
ornamentals and the tendency of sulfur to settle down when in liquid form (Olkowski, W. et
al, Common Sense Pest Control, p. 109). Some plants are sensitive to sulfur and plant
damage can occur when temperatures during application are greater than 30°C. Sulfur is
available in particulate form. It is difficult to combine a particulate fungicide with an oil based
insecticide or oil itself.
Mineral oil is colorless, odorless, light mixture of alkanes in the C15 to C40 range from a nonvegetable
(mineral) source, particularly a distillate of petroleum. The basic classification as
outlined by Calpouzos(Oils. In Fungicides An Advanced Treatise, ed. DC Torgeson II 367-
93.New York: Academic 742 pp.) are the mineral oil (refined oil), fatty or fixed oils of plant or
animal origin and synthetic oils (for eg: silicone and polybutene oils). Although research
information is available on all these types, the only oils used routinely in agriculture are the
mineral oils. Mineral oils from the commercial refining process are heavy distillates that
contain hundreds of chemical compounds present in different proportions depending on the
origin and lot of the oil. Mineral oils are classified as either paraffinic or napthenic depending
on whether they are composed primarily of long chain, unbranched hydrocarbon, as in the
case for the paraffinic oils or if they are napthenic, whether they are composed of ringed
compounds with short highly branched side chains (Anne Rev. phytopathalology 1978
16:211-37 by P.A. Backman).
The fungicidal, insecticidal and adjuvant properties of oils have been known for many years
but in the last 25 years the economic importance in several crops has been established.
Oils may act as spreader, stickers, carriers or as fungicidal chemicals.
Formulators of oils for agriculture monitor several factors that greatly affect phytotoxicity and
fungicidal performance. The first of these is the unsulfonated residue (UR) which measures
the degree of saturation of the oil. The higher the UR, the greater the amount of saturates
and the lesser the amount of aromatics. Distillation range measures the volatility of oil; in
general, oils with low volatility are used in agriculture. Viscosity is a major characteristic
involved in oil selection and a great body of literature exists relating the SUS value (Saybolt
universal seconds, 37.8°C) to fungicidal efficacy. Further acid value is another value
frequently considered and should be low to reduce the probability of phytotoxicity.
4
Petroleum oils are used in agriculture as carriers or solvents for spraying pesticides
(fungicides, insecticides, ovicides, etc.), herbicides, micronutrients and various types of
chemical adjuvants. They are also used as agricultural spray oils in their own right, i.e.,
without additives, because of their natural pesticidal properties. They control a wide range of
pests, for examples, Sigatoka disease in banana, earworm in sweet corn, Cercospora in
sugar beet, and mites, aphids, scale insects in deciduous fruit trees, citrus and ornamentals.
The main advantage of petroleum spray oils are their relative cheapness, their low health
hazard and the apparent inability of fungi, insects and mites to develop strains resistant to
them.
The fungicidal composition of granular sulfur and mineral oil is known in the art. However,
sulfur in granular form combined with mineral oil tends to show more of a fungicidal activity
other than a desired insecticidal activity as well. Sulfur in low amount of 1 to 35% of the total
formulation will act as fungicide. If a higher amount of sulfur is used, it tends to show other
pesticidal activities. However, developing a formulation with high loading of sulfur in
combination with mineral oil is still a problem unsolved in the art.
DE2414216 discloses granulated sulfur mixture containing granular Sulfur 80-90%, mineral
oil 10-15% and 0.2-5% of a conditioning agent such as Aerosil (fumed silica), which are roll
granulated to form a product of 2-4 mm size. The granules of said patent are bigger in size
which is not easy for application in the field and causes undue phytotoxicity due to residue
formation after application.
Free flowing powdered sulfur is disclosed in US Patent No. 2022796 prepared by melting the
sulfur and incorporating the mineral oil with flash point of about 300 °F in the molten sulfur
followed by cooling and grinding the sulfur. However, this does not disclose sulfur in
suspended form in aqueous medium in combination with paraffinic mineral oil which will
eliminate residue formation and thus phytotoxicity caused by sulfur.
US Patent No. 3431214 discloses process for making non-dusting, free flowing sulfur pellets
by compacting a mixture of sulfur with petrolatum. The said composition suffers from the
problems of residue formation and phytotoxicity associated with it.
5
US Patent No. 6835719 discloses pesticidal liquid suspension composition including a
mixture of sulfur combined with pyrethrins and/or pyrethroids. The composition can be
prepared as concentrated or ready-to-use formulations. However, this does not disclose
sulfur in liquid suspension and hence does not eliminate phytotoxicity due to unwanted
residue formation. Presence of high amount of sulfur in a formulation imparts instability
hence amount of sulfur in a formulation is reduced.
It is apparent from the above that combination of granular sulfur and mineral oil is known in
the art and problems in formulating stable composition of granular sulfur and mineral oil
individually is also known in the art. Further, mineral oil and sulfur are incompatible with each
other and difficult to combine in a single formulation as oil is known to increase the
phytotoxicity of the sulfur in the formulation. Several drawbacks are associated with the
known formulation of sulfur and mineral oil such as high sulfur toxicity, residue formation,
instability and difficulty to employ in the field and increase in phytotoxicity. Particulate sulfur
also settles down in liquid formulation and hence requires a suspension system to be
suspended in liquid. As a result, commercial sulfur labels contain cautions against mixing
sulfur with oil and carry warnings such as: "do not use within 30 days of an oil spray and do
not mix with oil." (US6835719 Parker Diana L et.al)
Hence, there is a need in the art to develop a stable formulation of mineral oil and sulfur that
overcomes the above drawbacks of the known formulations and yet have a superior
insecticidal efficacy.
Object of the invention:
Therefore, it is an object of the present invention to provide a process for preparing a stable
suspension concentrate formulation of sulfur.
It is another object of the present invention to provide an eco-friendly stable suspension
concentrate of mineral oil in combination with sulfur wherein the resultant combination
displays excellent stability, low residue formation, a superior insecticidal efficacy, is easy to
spray and has low phytotoxicity.
Yet another object of the present invention is to provide a process for the preparation of an
eco-friendly stable combination of a suspension concentrate of mineral oil and sulfur.
6
Summary of the invention:
According to one aspect of the present invention there is provided a composition comprising:
(a) a pesticidally effective amount of mineral oil; and
(b) a suspension concentrate comprising particulate sulfur suspended in an aqueous
medium, said aqueous medium additionally comprising at least one wetting agent,
optionally at least one anti-foaming agent and optionally at least one thickener
wherein said particulate sulfur has a particle size diameter distribution of D90 less than
about 10 microns.
According to another aspect of the present invention, there is provided a suspension
concentrate formulation of sulfur comprising particulate sulfur suspended in an aqueous
medium comprising at least one wetting agent wherein said particulate sulfur has a particle
size diameter distribution of D90 less than about 10 microns.
According to yet another aspect of present invention there is provided a process for
preparation of suspension concentrate of sulfur, said process comprising:
(a) mixing a predetermined quantity of water, at least one wetting agent,
optionally at least one anti-foaming agent along with raw sulfur;
(b) grinding the mixture of step (a) and filtering through mesh of a
predetermined size;
(c) mixing a second quantity of water and at least one thickener in another
vessel and obtaining a thickener premix;
(d) mixing the thickener premix of step (c) and ground sulfur of step (b) in
another vessel; and
(e) filtering the mixture of step (d) through a predetermined mesh size.
In another aspect the present invention provides a method of treating a locus, said method
comprising subjecting the locus to a first treatment, at the beginning of an agricultural
season, with a formulation comprising:
(a) an insecticidally effective amount of mineral oil;
7
(b) a suspension concentrate comprising particulate sulfur suspended in an aqueous
medium, said aqueous medium additionally comprising at least one wetting agent,
optionally at least one anti-foaming agent and optionally at least one thickener
wherein said particulate sulfur has a particle size diameter distribution of D90 less
than about 10 microns; and
(c) subjecting said treated locus with at least a second pesticide treatment after a
predetermined time.
Detailed Description of the invention:
The term "pesticidally effective amount" of mineral oil is that quantity of mineral oil which
when applied in that 'amount will provide the required control of insect and pests. The
particular amount is dependent upon many factors including, for example, the crop, pest to
be controlled and environmental conditions. The selection of the proper quantity of active
agent to be applied, however, is within the expertise of one skilled in the art and is not
considered particularly limiting.
Surprisingly, it has been found that an eco-friendly, stable formulation comprising a
suspension concentrate of sulfur in combination with mineral oil exhibited excellent stability,
low residue formation, is easy to spray, displays an unexpected insecticidal efficacy and has
very low phytotoxicity.
Formulators face many challenges while formulating mineral oil and Sulfur into an
agrochemical formulation. It is difficult to develop a synergistic formulation of mineral oil and
sulfur as mineral oil is known to increase the phytotoxicity of the formulation.
The present inventors have developed a suspension concentrate comprising particulate
sulfur having size of about less than 10 microns, preferably less than 3 microns. The lower
particle size aids in suspending the particulate sulfur in the formulation of the present
invention. The sulfur also acts as stabilizer in the present formulation.
Therefore, in this aspect, the present invention provides a suspension concentrate
formulation of sulfur comprising particulate sulfur suspended in an aqueous medium
comprising at least one wetting agent, optionally at least one anti-foaming agent and
8
optionally at least one thickener wherein said particulate sulfur has a particle size diameter
distribution of D90 less than about 10 microns.
In another aspect, the present invention provides a process for preparation of suspension
concentrate of sulfur, said process comprising :
a) mixing a predetermined quantity of water, at least one wetting agent, optionally an
anti-foaming agent along with raw sulfur;
b) grinding the mixture of step (a) and filtering through mesh of a predetermined size;
c) mixing a second quantity of water and at least one thickener in another vessel and
obtaining a thickener premix;
d) mixing the thickener premix of step (c) and ground sulfur of step (b) in another
vessel; and
e) filtering the mixture of step (d) through mesh of 100 µm.
In an embodiment, the predetermined quantity and the second quantity of water are not
particularly limiting and may be selected by a skilled artisan on the basis of the quantities of
remaining ingredients.
In another embodiment, the predetermined mesh size is not particularly limiting and may be
conveniently selected by a skilled artisan. Preferably, the mesh size is 250 µm in an
embodiment.
In an embodiment, the wetting agent is selected from nonionic surfactants such as alcohol
ethoxylates for example of C9 to C15, particularly primary alcohols, which may be linear or
branched, particularly mono-branched, ethoxylates with from 5 to 30 moles of ethylene
oxide; and alkoxylates of such alcohols particularly mixed ethoxylate/propoxylates which
may be block or random mixed alkoxylates, typically containing from 3 to 10 ethylene oxide
residues and from 1 to 5 propylene oxide residues, particularly where the polyalkoxylate
chain is terminated with propylene oxide unit(s); polyoxyethylene/polyoxypropylene
copolymers, particularly block copolymers, such as the Synperonic PE series of copolymers
and Atlas G 5000 available from Uniqema, and alkyl polysaccharides; anionic surfactants
e.g. isethionates, such as sodium cocoyl isethionate, naphthalene sulphonic acids or
sulphosuccinates in an amount of about 0.1% to 5% by weight.
9
In another embodiment, the optional anti-foaming agent included within the formulations of
the present invention may be selected from but are not limited to stearates; silicones;
dimethyl polysiloxanes and ethoxylates. Preferably, the anti- foaming agent is dimethyl
polysiloxanes or a silicone based defoamer. In an embodiment, the anti-foaming agent may
be present within the formulations according to the present invention in an amount of about
0.1% to about 5% by total weight of the formulation.
The present inventors have thus developed an eco-friendly stable formulation which
eliminates all the drawbacks of combining mineral oil and sulfur and obtained a formulation
which exhibits reduced phytotoxicity, low residue formation, is easy to apply and has a
superior insecticidal efficacy. Without wishing to be bound by any theory, the present
invention describes a stable formulation despite a high concentration of sulfur. It has been
long believed that increase in the amount of sulfur affects the stability of the formulation.
However, the present invention is stable and also shows a superior insecticidal efficacy.
Thus, in another aspect, the present invention provides an eco-friendly stable formulation
comprising:
(a) a pesticidally effective amount of mineral oil; and
(b) a suspension concentrate comprising particulate sulfur suspended in an aqueous
medium, said aqueous medium additionally comprising at least one wetting agent,
optionally at least one anti-foaming agent and optionally at least one thickener
wherein said particulate sulfur has a particle size diameter distribution of D90 less
than about 10 microns.
In an embodiment, the present invention describes an eco-friendly stable formulation
comprising mineral oil in combination with a suspension concentrate of particulate sulfur
having excellent stability in accelerated conditions, low residue formation, a superior
insecticidal efficacy, is easy to employ in the field and low phytotoxicity.
In another embodiment, the present invention describes an eco-friendly stable formulation
comprising mineral oil in combination with a suspension concentrate of particulate sulfur
along with optionally selective use of thickener and agrochemically acceptable adjuvants.
10
In an embodiment, the mineral oil component in the formulations according to the present
invention may be selected from paraffinic mineral oil or refined petroleum oil. In an
embodiment, the mineral oil may be present in an amount of about 20-60% by weight and
sulfur is present in an amount of upto 5-15% by weight, however these amounts are not to
be construed as limiting.
Therefore, in another preferred embodiment, the present invention describes combination of
mineral oil and suspension concentrate of sulfur optionally along with a thickener which
enable the sulfur particles to be suspended in the solution and also provides stability to the
formulation.
Thus, in this embodiment, the present invention provides an eco-friendly stable formulation
comprising:
(a) a pesticidally effective amount of mineral oil; and
(b) a suspension concentrate comprising particulate sulfur suspended in an aqueous
medium, said aqueous medium additionally comprising at least one wetting agent,
optionally at least one anti-foaming agent and optionally at least one thickener
wherein said particulate sulfur has a particle size diameter distribution of D90 less
than about 10 microns.
Thus, the preferred formulations according to an embodiment of the present invention
preferably include at least one thickener. The thickener according to the present invention
may be selected from a heteropolysaccharide or a synthetic or natural gum. The gum may
preferably be in the form of a gel of predetermined strengths such as 2 percent. The
thickener may be present in an amount of about 0.1 % to about 5% by total weight of the
formulation.
Suitable adjuvants according to present invention are selected from surfactants, antifoaming
agent, biocide and solvents.
In an embodiment, the surfactant may be selected from salts of naphthalenesulphonic
acid/formaldehyde condensates, salts of condensates of naphthalenesulphonic acid,
phenolsulphonic acid and formaldehyde preferably fatty alcohol ethoxylate, sodium
11
naphthalene formaldehyde condensate. The surfactant may be present in an amount of
about 0.2 to about 5% by total weight of the formulation.
The preferred formulations according to the present invention may further include at least
one anti- foaming agent. The anti-foaming agent included within the formulations of the
present invention may be selected from but are not limited to stearates; silicones; dimethyl
polysiloxanes and ethoxylates. Preferably, the anti- foaming agent is dimethyl polysiloxanes
or a silicone based defoamer. In an embodiment, the anti-foaming agent may be present
within the formulations according to the present invention in an amount of about 0.1% to
about 5% by total weight of the formulation.
Preferably, the formulations of the present invention further include a biocide, which may be
a mixture comprising dipropylene glycol, 1, 2-bezisothiazolin-3-one or sodium hydroxide and
water. However, it should be understood that the present invention is not limited to these
specific biocides and other biocides that are known in the art may also be conveniently used.
The biocide may be present within the formulations according to the present invention in an
amount of about 0.1 to about 0.5% by total weight of the formulation. The formulation of the
present invention also includes solvent such as distilled water.
In another embodiment, the present invention provides a process for preparation of an ecofriendly
stable formulation comprising the steps of:
a) mixing water and at least one surfactant followed by adding (a) a suspension
concentrate comprising particulate sulfur suspended in an aqueous medium, said
aqueous medium additionally comprising at least one wetting agent; (b) an
insecticidally effective amount of mineral oil, (c) optionally at least one thickener and
(d) optionally at least one anti-foaming agent under constant mixing;
b) mixing water and at least one thickener in another vessel and obtaining a thickener
premix;
c) mixing thickener premix of step (c) with mixture of step (a);
d) filtering the mixture of step (c) through mesh of 100 µm.
In another embodiment, the predetermined mesh size in step (d) is not particularly limiting
and may be conveniently selected by a skilled artisan. Preferably, the mesh size is 100 µm
in this embodiment.
12
Sulfur is known to be quite difficult to grind and to get the desired particle size. The speed of
the flow through the ceramic bead mills is adjusted to obtain the desired particle size. The
process is cooled at each step of the grinding (50°C max.). There is no particular problem
with the mixture of suspension concentrate and oil (stirrers at 1500 and 3000 revolutions a
minute). However the sulfur in particulate form in liquid system forms residue or settles
down.
In another embodiment, the preferred formulation of the present invention includes at least
another pesticide.
Thus, in another embodiment, the present invention provides an eco-friendly stable
formulation comprising:
(a) an effective amount of mineral oil;
(b) a suspension concentrate comprising particulate sulfur suspended in an aqueous
medium, said aqueous medium additionally comprising at least one wetting agent,
optionally at least one anti-foaming agent and optionally at least one thickener
wherein said particulate sulfur has a particle size diameter distribution of D90 less
than about 10 microns; and
at least another pesticide.
In a preferred embodiment, the at least another pesticide may be selected from the group
comprising copper and dithiocarbamate compounds such as thiram, ziram, mancozeb.
The formulation of the present invention may be conveniently prepared in concentrated form
or in a ready-to-use form.
The composition of the present invention may be applied in areas that are infected with
insect and mite pests, garden areas, and on or around trees, plants, and shrubs. The
composition of the present invention is eco-friendly composition having low phytotoxicity and
thus may be applied to a variety of plants, flowers, trees, shrubs, and grasses.
Thus, in this embodiment, the present invention describes a method of treating a locus, said
method comprising subjecting the locus to a first treatment, at the beginning of an
13
agricultural season, with a formulation comprising (a) an insecticidally effective amount of
mineral oil; (b) a suspension concentrate comprising particulate sulfur suspended in an
aqueous medium, said aqueous medium additionally comprising at least one wetting agent,
optionally at least one anti-foaming agent and optionally at least one thickener wherein said
particulate sulfur has a particle size diameter distribution of D90 less than about 10 microns.
The composition of the present invention is applied at beginning of the season as the same
act against many pests. The present composition is the perfect application of the concept of
eco-friendly wide spectrum product. The application of the present composition at
beginning of the season is the fundamental against some pest like scales and mite where
all the application during the season do not show good efficacy due to fatal combination of
the pest biological cycle and the limit of the applications on the canopy. The present
composition act against the over wintering stage (eggs and neanid/adult forms) reducing the
damage potential.
In another embodiment, the method according to the present invention comprises subjecting
the locus to at least a second pesticidal treatment. Thus, in this embodiment, the present
invention provides a method of treating a locus, said method comprising:
(a) subjecting the locus to a first treatment, at the beginning of an agricultural season,
with a formulation comprising (a) an insecticidally effective amount of mineral oil; (b)
a suspension concentrate comprising particulate sulfur suspended in an aqueous
medium, said aqueous medium additionally comprising at least one wetting agent,
optionally at least one anti-foaming agent and optionally at least one thickener
wherein said particulate sulfur has a particle size diameter distribution of D90 less
than about 10 microns; and
(b) subjecting said treated locus with at least a second pesticide treatment after a
predetermined time.
The second pesticidal treatment may be carried out after a predetermined time. The
predetermined time varies between a simultaneous application and a time period of about
one week subsequent to the first treatment. Preferably, the second treatment is carried out
after one week from the first treatment.
14
In another embodiment, the locus may be subjected to a third pesticidal treatment after a
predetermined time. The third predetermined time varies between a simultaneous
application with the first and second treatments and a time period of about one week
subsequent to the first treatment. Preferably, the third treatment is carried out about one
week from the second treatment.
Thus, in this embodiment, the present invention provides a method of treating a locus, said
method comprising:
(a) subjecting the locus to a first treatment, at the beginning of an agricultural season,
with a formulation comprising (a) an insecticidally effective amount of mineral oil; (b)
a suspension concentrate comprising particulate sulfur suspended in an aqueous
medium, said aqueous medium additionally comprising at least one wetting agent,
optionally at least one anti-foaming agent and optionally at least one thickener
wherein said particulate sulfur has a particle size diameter distribution of D90 less
than about 10 microns;
(b) subjecting said treated locus to at least a second pesticide treatment after a
predetermined time; and
(c) subjecting said second treated locus to a third pesticide treatment after a
predetermined time.
In an embodiment, the second and third treatments comprise treating the first or second
treated locus respectively with an effective amount of a second pesticide. In this
embodiment, the second or third pesticide may be preferably selected from a herbicide,
fungicide or an insecticide that is known in the art. In a preferred embodiment, another
pesticide is preferably a fungicide or an insecticide.
In an embodiment, the second and third pesticide may be selected from copper and
dithiocarbamate compounds such as thiram, ziram, mancozeb. In this embodiment, the
preferred formulation type, the pesticidally effective amount dosage etc. of the second and
third pesticide is not particularly limiting and may be conveniently selected by a person
skilled in the art.
In an embodiment, the second pesticide treatment comprises subjecting the first treated
locus with an emulsifiable concentrate formulation of mineral oil or a granular formulation of
15
sulfur individually. In this embodiment, the second pesticidal treatment is carried out about a
week subsequent to the first treatment.
In another embodiment, the third pesticide treatment comprises subjecting the second
treated locus with an emulsifiable concentrate formulation of mineral oil or a granular
formulation of sulfur individually. In this embodiment, the third pesticidal treatment is carried
out about a week subsequent to the second treatment.
The formulation of the present invention is effective against a wide range of pests including,
but not limited to, gray scale, eriophids, wooly aphis, pear sucker, White scale, San José
scale, Acarinosis, Powdery mildew (side effect), Black scale, Rust mite, Cornel cherry scale,
FD's Leaf hopper, Hazelnut gall mite, Hazelnut scale, Leaf blister mite.
Trials were conducted to study the wide insecticidal activity spectrum of the present
formulations. The comparative study of formulation of present invention vis-à-vis Tank mix
mineral oil (800g/L) and sulfur 80% WDG or sulfur alone was studied. The Dosage rate was
5L/hl = 2000 g a.i. oil/hl + 480 g a.i. sulfur/hl. The compositions were sprayed just at the
beginning of the growth season on Pome fruits, Stone fruits and grapevine. It was found that
the composition of the present invention was more effective in controlling the wide variety of
pests as compared to the Tank mix of Mineral oil (800g/L) and sulfur 80% WDG or sulfur
alone.
These and other advantages of the invention may become more apparent from the
examples set forth herein below. These examples are provided merely as illustrations of the
invention and are not intended to be construed as a limitation thereof.
Examples:
Although the present invention has been disclosed in full, it will be understood that numerous
additional modifications and variations could be made thereto without departing from the
scope of the invention.
Example 1:
Table 1
Sr. Ingredients
16
No. g/kg or g/L %(w/w)
1. Refined Petroleum oil 400.0 g/L 41.7%
2. Sulfur 95.0 g/L 9.9%
3. Fatty alcohol ethoxylate 48.0 g/L 5.0%
4. Water Up to 1L ≤
425.5g/L
Up to 100% ≤
43.43%
Process:
a) mixing water and Fatty alcohol ethoxylate followed by addition of suspension concentrate
of particulate sulfur suspended in an aqueous medium and
b) adding Refined Petroleum oil to the mixture of step (a) under constant mixing to obtain a
stable composition.
Example 2:
Evaluation of the efficacy of mineral oil in mixture with Sulfur 80% WDG and
formulations according to Example 1 of present invention against Pseudaula
caspispentagona on peach tree.
Table 2
Observation
No.
1 2 3 4 5 6
Pest Code* PSEAPE PSEAPE PSEAPE PSEAPE PSEAPE PSEAPE
Part/Sub
Eval*
INSECT INSECT INSECT INSECT INSECT INSECT
Evaluation
Type*
LIVE DEAD PARASTIM LIVE DEAD PARASTIM
Eval
Unit/Scale*
NUMBER NUMBER NUMBER NUMBER NUMBER NUMBER
Sample Size 1 1 1 1 1 1
Sample Unit* PLOT PLOT PLOT PLOT PLOT PLOT
Subsample
Size
200 200 200 200 200 200
Subsample
Unit*
INSECT INSECT INSECT INSECT INSECT INSECT
Trt-Eval
Interval
0DAAA 0DAAA 0DAAA 112DAAA 112DAAA 112DAAA
UNTREATED 101 21 61 69 108 23
Example 1 12 61 23 24 156 20
Mineral Oil +
Sulfur 80%
WDG
72 36 90 37 69 94
UNTREATED 120 42 96 68 68 64
Example 1 73 57 23 36 96 59
17
Mineral Oil +
Sulfur 80%
WDG
141 33 53 73 53 95
From the above table 2, it is concluded that formulation of Example 1 used at the rate of 5
l/hl has statistically shown in each trial an efficacy of 60.06% to 69.69% higher than the
mixture of Mineral oil at the rate of 2,5 l/hl and Sulfur 80% WDG at 600 g/hl.
Example 3:
Evaluation of the efficacy of mineral oil in mixture with Sulfur 80% WDG and
formulation of Example 1 (2.5 and 5l/hl) against Scale (Targionia vitis) on Grape vine
The mixture of Mineral oil (2.5l/hl) and Sulfur 80% WDG (0.6kg/hl) and formulation of
Example 1 was sprayed on Grape vines using a spray volume of 1000 L/ha. The effect was
assessed after 2 months of the spraying.
Table 3
Sr. No. Product treatment % of efficacy Life form/cm2 killed
1. Untreated -
2. Mineral oil (2.5l/hl)
and sulfur 80% WDG
(0.6kg/hl)
40 % 300 life form/cm2
3. Formulation of
Example 1
80% 600 life form/cm2
Hence, it was concluded that formulations according to Example 1 was 100 % more
efficacious than Mineral oil (2.5l/hl) and Sulfur 80% WDG (0.6kg/hl) in killing Scale
(Targioniavitis) on Grape vine.
Example 4:
Evaluation of the efficacy of mineral oil in mixture with Sulfur 80% WDG and
formulation of Example 1 (5l/hl) against Scale (Parthenolecanium corni) on Grape vine
The mixture of Mineral oil (2.5l/hl) and Sulfur 80% WDG (0.5kg/hl) and formulation of
Example 1 was sprayed on Grape vines.
18
Spray volume: 1000 l/ha; effect was assessed after 2 months of the spraying.
Table 4
Sr. No. Product treatment % of dead Life
form/sprout
1. Untreated *
2. Mineral oil (2.5l/hl) and Sulfur 80%
WDG (0.5kg/hl)
60% life form/cm2
3. formulation of Example 1 90% life form/cm2
Hence it was concluded that formulation of Example 1 showed better activity in comparison
with the extemporary mixture specially in the “green class” where formulation of example 1
was 30 % more efficacious than Mineral oil (2.5l/hl)and Sulfur 80% WDG (0.5kg/hl) mixture
in killing Scale (Parthenolecanium corni) on Grape vine.
Example 5:
Evaluation of the efficacy of Mineral oil in mixture with Sulfur 80% WDG and
formulation of Example 1 (2.5 and 5l/hl) against eriophids (Calepitrimerus vitis) on
Grape vine.
The mixture of Mineral oil (2.5l/hl) and Sulfur 80% WDG (0.6kg/hl) and formulation of
Example 1 (2.5 and 5l/hl) was sprayed on Grape vines. Spray volume: 1000 l/ha; effect was
assessed after 55 days of the spraying. The efficacy was assessed in the form of %
frequency leaves damage prevented.
Table 5
Sr. No. Product treatment % leaves damage
prevented
1. Untreated Less than 10 %
2. Mineral oil (2.5l/hl)
and Sulfur 80% WDG
(0.5kg/hl)
55 % leaves damage
prevented
3. Formulation of
Example 1 (2.5l/hl)
88 % leaves damage
prevented
4. formulation of
Example 1 (5l/hl)
88 % leaves damage
prevented
19
Hence it was concluded that formulation of Example 1 (2.5l.hl and 5l/hl) showed better
activity in comparison with the extemporary mixture where formulation of Example 1 was 30
% more efficacious than Mineral oil (2.5l/hl) and Sulfur 80% WDG (0.6kg/hl) mixture in
killing eriophids (Calepitrimerus vitis) on Grape vine.
Example 6:
Evaluation of the efficacy of Mineral oil in mixture with Sulfur 80% WDG and
formulation of Example 1 (5l/hl) against white scale on Peach.
The mixture of Mineral oil (2.5l/hl) and Sulfur 80% WDG (0.6kg/hl) and formulation of
Example 1 (5l/hl) was sprayed on Grape vines. Spray volume: 1500 l/ha; effect was
assessed after 5 months of the spraying. The efficacy was assessed in the form of number
of alive neanids/200 neanids.
Table 6
Sr. No. Product treatment Plot 1(No of alive
neanids/ 200
neanids)
Plot 2 (No of alive
neanids/ 200
neanids)
1. Untreated 92 alive neanids/
200 neanids
100 alive neanids/
200 neanids
2. Mineral oil (2.5l/hl)
and Sulfur 80%
WDG (0.5kg/hl)
100 alive neanids/
200 neanids
138 alive neanids/
200 neanids
3. formulation of
Example 1
(2.5l/hl)
31 alive neanids/
200 neanids
31 alive neanids/ 200
neanids
After the application of Mineral oil (2.5l/hl) and Sulfur 80% WDG (0.6kg/hl) approximate 69%
of alive neanids/ 200 neanids were observed and after the application of formulation of
Example 1 approximate 15 % of alive neanids/ 200 neanids. Hence it was concluded that
formulation of Example 1 showed better activity in comparison with the extemporary mixture.
Example 7:
Comparative Evaluation of the efficacy of formulations according to Example 1
against l° generation of Cacopsylla pyri on pear tree.
20
Table 7
Treat Active
ingredient
content Form
T1 Mineral oil +
sulfur of example
1
400 + 96 SE
T2 Mineral oil 800 EC
T3 sulfur 825 SC
T4 - - -
Table 8: Application rates
Treat Product Dosage rate
formulated
product (mL
org/hl)
Dosage a.i.
(g/hl)
Timing
T1 Present
formulation
5000 2000 A
T2 Mineral oil 1500 1200 B and C
T3 Sulfur 800 600 B and C
T4 Untreated - - -
A= breaking buds
B= 7days after A
C= 7days after B
The efficacy was evaluated by counting the total number of C. Pyri in 25 shoots randomly
chosen in the central plants of each plot.
A field infested with Cacopsylla Pyri was subjected to a first treatment with the formulation of
example 1. A portion of the plot was subsequently treated with an emulsifiable concentrate
of mineral oil or a granular formulation of sulfur about a week subsequent to the first
treatment. The respective portions were subjected to a third treatment respectively with an
emulsifiable concentrate of mineral oil or a granular formulation of sulfur about a week
subsequent to the second treatment. This study was conducted to qualitatively determine the
results of the subsequent pesticidal treatments on the locus treated with the formulation of
example 1. It was found that formulation of Example 1 was effective in treatment of
21
Cacopsylla pyri. Surprisingly, the efficacy of treatment was found to substantially increase
with the second and third treatments when the first treatment was carried out using the
formulation of example 1 of the present invention. The results of the treatment were
tabulated as hereunder:
Table 9
Treatment Mean Total
“e”
Mean Total
“n”
Mean Total
“N”
Mean Total
“e+n+N”
Treatment
using
formulation of
example 1
870.50 8 0 878.5
Example 1
(t=0) – Mineral
oil EC (t = 1
week) –
Mineral Oil (t=
2 weeks)
787.5 0.25 0 788.0
Example 1
(t=0) – Sulfur
WDG (t=1
week) – Sulfur
WDG (t=2
weeks)
560.50 14 0 574.5
Untreated 908.00 787.5 62.25 1049.0
Transformation NONE ASIN
(SQRT(X/100))
NONE NONE
p-value 0.1970 0.0008 0.0000 0.0300
N=nymphs; n= neanids; e=eggs
It was thus found that combining the first treatment step with the formulation of example 1
followed by second and third pesticide treatments provided greater percentage efficacy.
Advantages of one or more aspects or embodiments of the present invention:
22
The formulation of the present invention has following advantageous properties:
a) Excellent stability inspite of high concentration of sulfur
b) No phytotoxicity
c) A superior insecticidal efficacy compared to standard mineral oil.
d) No residue formation
e) Easy to apply
f) Is Eco friendly
g) Reduces the risk of resistance development
h) Avoids the side effect against fungi (i.e. cleistotecia of grapevine powdery mildew)
The invention has been described above with reference to the specific examples. It should
be noted that the example(s) appended above illustrate rather than limit the invention, and
that those skilled in the art will be able to design many alternative embodiments without
departing from the scope of the appended claims. Other than in the operating examples
provided hereinbefore or where otherwise indicated, all numbers expressing quantities of
ingredients or reaction conditions are to be understood as being modified in all instances by
the term "about".
WE CLAIM:
1. A composition comprising
(a) a pesticidally effective amount of mineral oil; and
(b) a suspension concentrate comprising particulate sulfur suspended in an
aqueous medium comprising at least one wetting agent wherein said
particulate sulfur has a particle size diameter distribution of D90 less than
about 10 microns.
2. The composition as claimed in claim 1, wherein said particulate sulfur has a particle
size less than 3 microns.
3. The composition as claimed in claim 1, wherein said aqueous medium additionally
comprises at least one ingredient selected from at least one anti-foaming agent and
at least one thickener.
4. The composition as claimed in claim 1, wherein said wetting agent is selected from
nonionic surfactants such as alcohol ethoxylates for example of C9 to C15 of
particularly primary alcohols, which may be linear or branched, particularly monobranched,
ethoxylates with from 5 to 30 moles of ethylene oxide; and alkoxylates of
such alcohols particularly mixed ethoxylate/propoxylates which may be block or
random mixed alkoxylates, typically containing from 3 to 10 ethylene oxide residues
and from 1 to 5 propylene oxide residues, particularly where the polyalkoxylate chain
is terminated with propylene oxide unit(s); polyoxyethylene/polyoxypropylene
copolymers, particularly block copolymers, alkyl polysaccharides; anionic surfactants
and isethionates, such as sodium cocoyl isethionate; naphthalene sulphonic acids or
sulphosuccinates.
5. The composition as claimed in claim 1, wherein said wetting agent in present in an
amount of about 0.1% to 5% by weight.
6. The composition as claimed claim 3, wherein said anti-foaming agent is selected
from stearates; silicones; dimethyl polysiloxanes and ethoxylates.
7. The composition as claimed 3, wherein said anti-foaming agent is present in an
amount of about 0.1% to about 5% by total weight of the composition.
8. The composition as claimed in claim 1 comprising upto 10% of particulate sulfur
suspended in an aqueous medium.
24
9. The composition as claimed in any one of the preceding claims wherein the mineral
oil component is selected from paraffinic mineral oil and refined petroleum oil.
10. The composition as claimed in claim 9, wherein said mineral oil component is
present in an amount of 20-60% by weight.
11. The composition as claimed in claim 3, wherein the thickener is selected from a
heteropolysaccharide or a synthetic or natural gum.
12. The composition as claimed in claim 3 comprising at least one thickener in an
amount of about 0.1 % to about 5% by total weight of the composition.
13. The composition as claimed in any one of the preceding claims comprising at least
one surfactant selected from salts of naphthalenesulphonic acid/formaldehyde
condensates, salts of condensates of naphthalenesulphonic acid, phenolsulphonic
acid and formaldehyde preferably fatty alcohol ethoxylate andsodium naphthalene
formaldehyde condensate.
14. The composition as claimed in claim 13, wherein said at least one surfactant is
present in an amount of about 0.2 to about 5% by total weight of the composition.
15. The composition as claimed in any one of the preceding claims comprising at least
one anti-foaming agent selected from stearates; silicones; dimethyl polysiloxanes
and ethoxylates.
16. The composition as claimed in any one of the preceding claims comprising at least
one biocide selected from dipropylene glycol,1,2-bezisothiazolin-3-one and sodium
hydroxide.
17. The composition as claimed in claim 16, where said at least one biocide is present in
an amount of about 0.1 to about 0.5% by total weight of the composition.
18. The composition as claimed in any one of the preceding claims additionally
comprising at least another pesticide.
19. The composition as claimed in claim 16, wherein said at least another pesticide is
selected from copper dithiocarbamate compounds such as thiram, ziram, mancozeb.
20. A suspension concentrate formulation of sulfur comprising particulate sulfur
suspended in an aqueous medium comprising at least one wetting agent wherein
25
said particulate sulfur has a particle size diameter distribution of D90 less than about
10 microns.
21. The suspension concentrate formulation of sulfur as claimed in claim 19, wherein
said particulate sulfur has a particle size is less than 3 microns.
22. The suspension concentrate formulation of sulfur as claimed in claim 19, wherein
said aqueous medium additionally comprises at least one ingredient selected from at
least one anti-foaming agent and at least one thickener.
23. A process for preparation of suspension concentrate of sulfur, said process
comprising :
a) mixing a predetermined quantity of water, at least one wetting agent,
optionally at least one anti-foaming agent along with raw sulfur;
b) grinding the mixture of step (a) and filtering through mesh of a
predetermined size;
c) mixing a second quantity of water and at least one thickener in
another vessel and obtaining a thickener premix;
d) mixing the thickener premix of step (c) and ground sulfur of step (b) in
another vessel; and
e) filtering the mixture of step (d) through a predetermined mesh size.
24. The process as claimed in claim 23, wherein the predetermined mesh size in step (b)
is about 250 µm.
25. The process as claimed in claim 24, wherein the predetermined mesh size in step (e)
is about 100 µm.
26. The process as claimed in claim 23 wherein step (a) comprises additionally mixing an
insecticidally effective amount of mineral oil.
27. A method of treating a locus, said method comprising subjecting the locus to a first
treatment, at the beginning of an agricultural season, with a formulation comprising
(a) an insecticidally effective amount of mineral oil; and (b) a suspension concentrate
comprising particulate sulfur suspended in an aqueous medium, said aqueous
medium additionally comprising at least one excipient selected from at least one
wetting agent, at least one anti-foaming agent and at least one thickener wherein
26
said particulate sulfur has a particle size diameter distribution of D90 less than about
10 microns.
28. The method as claimed in claim 27 comprising subjecting the locus to a second
pesticide treatment.
29. The method as claimed in claim 28, wherein said second treatment is carried out
about one week subsequent to the first treatment.
30. The method as claimed in any of the claims 27-29 comprising subjecting the locus to
a third pesticide treatment.
31. The method as claimed in claim 30, wherein said third treatment is carried out after
one week from the second treatment.
32. The method as claimed in claims 28-31, wherein said second and third treatments
comprise treating the first or second treated locus respectively with an effective
amount of a second or third pesticide.
33. The method as claimed in claim 28, wherein said second pesticide is selected from
an emulsifiable concentrate formulation of mineral oil or a granular formulation of
sulfur.