The invention relates to a fungicidal composition. More particularly, the invention
relates to a synergistic fungicidal composition comprising Difenoconazole and
Propineb.
BACKGROUND OF THE INVENTION
Most crop and ornamental plants are subject to attack by several fungi. Plant
disease damage to ornamental, vegetable, field, cereal and fruit crops can cause
significant reduction in productivity and thereby result in increased costs to the
consumer. In addition to often being highly destructive, plant diseases can be
difficult to control and may develop resistance to commercial fungicides. The
diversity of these organisms and their potential for inciting serious disorders in
combination or singly has resulted in the need for broad-spectrum disease control.
Although there are available numerous chemical compounds (fungicides), which
aid in preventing diseases of plants, each of these have practical deficiencies,
which restrict its use. Combinations of fungicides are often used to facilitate
disease control, to broaden spectrum of control and to retard resistance
development. Accordingly new advantageous combinations are needed to provide
a variety of options to best satisfy particular plant disease control needs.
Furthermore, certain rare combinations of fungicides demonstrate a greater-thanadditive
(i.e. synergistic) effect to provide commercially important levels of plant
disease control.
When two or more substances in combination demonstrate unexpectedly high
biological activity, for example fungicidal activity, the resultant phenomenon may
be referred to as synergism. The reason or mechanism for the synergy may not be
always known, and may differ with different combinations, but the effect can
always be observed experimentally. The term ‘synergism’ or ‘synergy’ hereinafter
refers to a cooperative action encountered in a combination of two or more
biologically active components in which the combined activity of the two or more
components exceeds the sum of the activity of each component alone.
1011/PAT APPLN/10
3
US 4474805 discloses a synergistic mixture of fungicides consisting of N-2-6-
dimethyl phenyl)-N-(l-methoxycarbonyl-ethyl)-phenyl-acetamide and a
dithiocarbamate selected from the group consisting of Zineb and Mancozeb. US
patent 6172094 discloses a synergistic mixture of Carbamate and a
dithiocarbamate selected from the group consisting of manganese ethylene
(dithiocarbamate) (Zinc complex), (mancozeb) manganese ethylene
bis(dithiocarbamate), (Maneb) zinc ammoniate ethylene bis (dithiocarbamate) and
zinc ethylene bis(dithiocarbamate) (Zineb) where in the weight ratio of the
dithiocarbamate to the carbamate is 200:1 to 0.1:1. US 4937261 discloses a
synergistic mixture of propyl 3-(dimethylamino) propyl carbamate or an acid
addition salt thereof, and a compound selected from the group consisting of
Propineb , Maneb, Metiram and zinc (Zineb) where in the weight ratio of the
Component A to component B is from about 1:0.1 to 3. However, above prior art
does not mention the combination of dithiocarbamate with a Triazole fungicide.
Fungicidal compositions containing Triazoles as active ingredients are known and
have been found be effective against fungal diseases such as scab, blast, sheath
blight, powdery mildew, tikka, leaf spot, fruit spot, etc. in economically important
crops such as apple, grape, groundnut, peas, mango etc. Triazole fungicides such
as Hexaconazole, Tebuconazole, Propiconazole and Difenoconazole are available
commercially in the form of wettable powder (WP), water dispersible granules
(WDG), emulsifiable concentrate (EC) and suspension concentrate (SC)
formulations. Considering the importance of effective control of a broad spectrum
of fungal diseases such as scab, blast, blight, mildew, tikka, leaf spot, fruit spot
etc. in economically important crops such as mango, tobacco, coconut, turmeric,
tea potato, etc. the need for a fungicidal composition which is stable, ready to use
and less expensive was felt.
Further, it has been observed that whenever two individual fungicides such as a
dithiocarbamate and a Triazole are used in combination, there is a better control of
fungal diseases than when they are used individually due to synergistic action. In
view of the above, obtaining an fungicidal combination which demonstrates no
cross-resistance to the existing fungicidal agents, no toxicity problems and little
1011/PAT APPLN/10
4
negative impact on the environment is extremely difficult. Thus, it is an objective
of this invention to provide a synergistic fungicidal combination which
demonstrate a high controlling effect along with reduced crop protection cost and
reduced environmental load. Accordingly, the present invention provides a
synergistic fungicidal combination comprising Difenoconazole and Propineb.
Difenoconazole, CAS-Number: 119446-68-3, (cis, trans-3-chloro-4-[4-methyl-2-
(1H-1,2,4-triazol-1-ylmethyl)-1,3-dioxolan-2-yl]phenyl 4-chlorophenyl ether) is a
fungicide, having the following chemical structure:
Difenoconazole is effective against a number of diseases caused by ascomycetes,
basidiomycetes and deuteromycetes including Alternaria, Ascochyta, Cercospora,
Cercosporidium, Colletotrichum, Guignardia, Mycosphaerella, Phoma,
Ramularia, Rhizoctonia, Septoria, Erysiphe, and Venturia spp., Erysiphaceae,
Uredinales and several seed borne diseases. Difenoconazole is described in "The
Pesticide Manual" [The Pesticide Manual - A World Compendium; Fifteenth
Edition, Editor: C. D. S. Tomlin, BCPC] at entry no. 266 on page no. 354.
Difenoconazole is one of the widely used broad-spectrum fungicide for disease
control in grapes, pome fruits, stone fruits, potatoes, sugar beet, oilseed rape,
bananas, cereals, rice, soybean, ornaments and vegetable crops. It has preventive
and curative action. In general, Difenoconazole is available as 25 percent
emulsifiable concentrate.
Difenoconazole is absorbed by the leaves with acropetal and strong translaminar
translocation. It acts by inhibition of sterol demethylation during cell membrane
ergosterol biosynthesis thereby stopping development of fungus. Despite being a
1011/PAT APPLN/10
5
broad spectrum fungicide its phytotoxic effects or phytotoxicity are reported in
literature. For example, F. Montfort et al., Pesticide Science 46(4), 1996, 315-322,
report that the use of azole fungicides, such as triticonazole, for the treatment of
seed and crop plants may have an adverse effect on plant growth.
WO2008/155416 describes use of gibberellins for reducing or preventing the
phytotoxic effect of azole fungicides or of azole fungicides used in combination
with anilide fungicides, primarily for seed treatment.
Dithiocarbamide fungicide is selected from group consisting of amobam, asomate,
azithiram, carbamorph, cufraneb, cuprobam, disulfiram, ferbam, metam, nabam,
tecoram, thiram, urbacide, ziram, dazomet, etem, milneb, mancopper, mancozeb,
maneb, metiram, polycarbamate, propineb and zineb.
Propineb (polymeric zinc propylenebis (dithiocarbamate)) is a chemical
compound selected from the group of the zinc compounds and dithiocarbamates ,
which is used as a fungicide. It is the propylene - analogue of zineb. Propineb is a
flammable, yellow solid which is slightly soluble in water and decomposes in
moist, acidic and alkaline media. It was first reported by H. Goeldner (pflanz.-
Nachr. Bayer (Engl. Ed.), 1963, 16, 49). Propineb can be described by the
following formula (I)
Propineb is a protectant foliar-applied fungicide with long residual activity and
belongs to the dithiocarbamate group of compounds. It is used as a protective
treatment on several crops for the control of various fungi, especially Oomycetes,
Ascomycetes, Basidiomycetes and Fungi imperfecti. Propineb controls blight on
potatoes and tomatoes, downy mildew on hops and vines, apple scab, blue mould
on tobacco and Sigatoka disease of bananas. It can also be used on gooseberries,
1011/PAT APPLN/10
6
black currants, celery and cereals. Propineb is applied as a Water dispersible
granule (WG or WDG) or Wettable powder (WP) formulation, mainly as a spray.
The standard composition of Propineb available in the art is 70 percent wettable
powder. Notably, Propineb is also useful as bird repellent and for the
physiological curative treatment under zinc deficiency. EP 2421371 A1 describes
its use as a bird repellent and WO 2011107443 A1 discloses use of Propineb for
physiological curative treatment under zinc deficiency.
Fungicidal combinations offer significant advantages over individual applications
including improved and extended fungal control, reduced fungicide application
rates and costs, shorter contact times for improved results, less stringent use
restrictions, improved selectivity, improved spectrum of fungi controlled, reduced
cost and reduced residue problems. However, identifying appropriate fungicide
application rates and ratio of the combinations is essential to achieve efficacious
disease control. Hitherto, there have been no studies to determine the mostefficacious
and synergistic ratios of Difenoconazole and Propienb, at which these
fungicides synergistically complement each other's fungicidal properties not seen
at other ratios. Thus there exists a need in the art for a composition comprising
Difenoconazole and Propineb at a ratio which shows superior and effective
control on fungal infections.
SUMMARY OF THE INVENTION
The present invention relates to synergistic fungicidal compositions for control of
fungi, delaying the appearance of the resistant strains of the fungal pathogens,
minimizing the risk of development of resistance and achieving effective and
economical control of undesired fungal pathogens.
In accordance with an embodiment of the invention, there is provided a
synergistic fungicidal composition, comprising: (a) Difenoconazole; and (b)
Propineb.
In the synergistic fungicidal composition of the present invention, Difenoconazole
and Propineb are present in a mass ratio in the range from 1:6.4 to 1:43.
1011/PAT APPLN/10
7
The synergistic fungicidal composition comprises Difenoconazole and Propineb
preferably in a ratio of 1:16.
In accordance with another embodiment of the invention, the synergistic
fungicidal composition comprises Propineb in an amount in the range from 32 to
64% and Difenoconazole in an amount of 1.5 to 5%.
The synergistic fungicidal composition, further comprising excipients, may be in
the form of an emulsion concentrate (EC), a suspo-emulsion (SE), a microemulsion
(ME), an oil-dispersion (OD), a capsulated suspension (CS), a water
dispersible granule (WG or WDG), or a suspension concentrate (SC).
The synergistic fungicidal composition of the present invention comprises,
excipients selected from the group consisting of an emulsifier cum dispersant, a
dispersing agent, a wetting agent, a defoamer, a rheology modifier, a
disintegration agent, a filler and combinations thereof, and wherein the
composition may preferably be in the form of an oil dispersion (OD) or a water
dispersible granule (WDG or WG).
In accordance with still another embodiment of the invention, the emulsifier cum
dispersant or the dispersing agent is present in an amount in the range from 1 to
20%, the wetting agent is present in an amount of 0 to 15%, the defoamer is
present in an amount of 0.01 to 0.50%, the rheology modifier is present in an
amount in the range from 0.10 to 3.00%, the disintegration agent is present in an
amount in the range from 0.10-5.00%.
In accordance with yet another embodiment of the invention, the composition is
non-phytotoxic and has good stability, wettability, suspensibility and
dispersibility.
In accordance with a further embodiment of the invention, there is provided a
method for effectively controlling pathogenic fungi at a locus, said method
comprising treating a locus with a composition comprising Propineb and
1011/PAT APPLN/10
8
Difenconazole in a fungicidally effective amount; wherein Propineb and
Difenconazole are present in a ratio of about 16:1.
DETAILED DESCRIPTION OF THE INVENTION
Discussed below are some representative embodiments of the present invention.
The invention in its broader aspects is not limited to the specific details and
representative methods. The illustrative examples are described in this section in
connection with the embodiments and methods provided. The invention according
to its various aspects is particularly pointed out and distinctly claimed in the
appended claims read in view of this specification and appropriate equivalents.
It is to be noted that, as used in the specification and the appended claims, the
singular forms "a", "an" and "the" include plural referents unless the context
clearly dictates otherwise. Thus, for example, reference to a composition
containing “a compound” includes a mixture of two or more compounds. It should
also be noted that the term “or” is generally employed in its sense including
“and/or” unless the content clearly dictates otherwise.
The expression of various quantities in terms of “% w/w” or “%” means the
percentage by weight, relative to the weight of the total solution or composition
unless otherwise specified.
The term "fungicidally effective amount" is that quantity of active agent or active
ingredient, applied in any amount which will provide the required control of fungi
and diseases. The particular amount is dependent upon many factors including, for
example, the crop, pest and disease sought 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. Further the term “active
ingredient” (A.I.) or “active agent” used herein refers to that component of the
composition responsible for control of fungal pathogens.
Compositions comprising a single fungicidally active component suffer from
numerous drawbacks such as development of resistant species, requirement of
high amount and concentration of the active ingredient, environmental damage,
1011/PAT APPLN/10
9
seepage of the active component into ground water, phyto-toxicity and harmful
effects on the health of animals and humans.
Accordingly, the inventors of the present invention have formulated a synergistic
insecticidal composition, comprising: (a) Difenoconazole; and (b) Propineb;
wherein Difenoconazole and Propineb are present in a mass ratio in the range
from 1:6.4 to 1:43.
The synergistic fungicidal composition of the present invention, further
comprising excipients, may be formulated as an emulsion concentrate (EC), a
suspo-emulsion (SE), a micro-emulsion (ME), an oil-dispersion (OD), a
capsulated suspension (CS), a water dispersible granule (WG or WDG), or a
suspension concentrate (SC).
Preferably, the synergistic fungicidal composition is in the form of an oil
dispersion (OD) or a water dispersible granule (WDG or WG) and the excipients
are selected from the group consisting of an emulsifier cum dispersant, a
dispersing agent, a wetting agent, a defoamer, a rheology modifier, a
disintegration agent, a filler and combinations thereof. The term “Oil dispersion
(OD)” used herein refers to stable suspensions of active ingredients in a waterimmiscible
fluid which may contain other dissolved active ingredients and is
intended for dilution with water before use. Further, the term “Water dispersible
granules” refers to granules that are obtained by blending and agglomerating a
ground solid active ingredient together with excipients.
The synergistic fungicidal composition preferably contains Propineb in an amount
in the range from 32 to 64% and Difenoconazole in an amount in the range from
1.5 to 5%.
It is generally observed that solid particles in a liquid undergo spontaneous
aggregation to form lumps. Hence it is recommended to add a dispersant or a
dispersing agent which prevents aggregation of solid particles and keeps them
suspended in the fluid. Accordingly, the composition of the present invention
preferably contains an emulsifier cum dispersant or a dispersing agent such as
1011/PAT APPLN/10
10
ethoxylated polyarylphenol phosphate ester or a mixture of sodium salt of
naphthalene sulfonate condensate and sodium lignosulfonate in an amount in the
range from 1 to 20%.
Wetting is the first stage of dispersion, in which the air surrounding the granular
composition is substituted with water. Wetting of the fungicidal composition with
water cannot occur if the surface tension of the liquid is very high. Hence, it is
recommended to add a wetting agent to the fungicidal composition to facilitate the
process of dispersion of the granules in the liquid. Accordingly, the composition
of the present invention preferably contains a wetting agent such as sodium lauryl
sulfate or a sodium alkyl naphthalene sulfonate blend in an amount in the range
from 0 to 15%.
A defoamer is usually added to a fungicidal composition, as foaming prevents
effective utilization of the tank in which said composition is diluted with water.
Hence, the fungicidal composition preferably contains dimethyl polysiloxane
emulsion as a defoamer in an amount in the range from 0.01 to 0.50%.
Rheology modifiers, commonly referred to as thickeners or viscosifiers, are
important constituents of agricultural composition. They serve the purpose of not
just altering the viscosity of the formulation but also that of providing specific
functionality to the product. In the present invention, they reduce the tendency of
the fungicidal composition to disperse when sprayed and decrease the likelihood
of it being rinsed off the crops. Hence, the composition of the present invention
contains rheology modifiers, preferably in an amount in the range from 0.10 to
3.00%.
The disintegration and dissolution of the water dispersible granules (WG or
WDG) can be further improved by adding effervescent components, i.e., citric
acid (an acid) and sodium bicarbonate (an alkali). Hence, these components are
preferably present in an amount in the range from 0.10-5.00%.
A filler is yet another important component of fungicidal compositions, which
improves handling and storage characteristics of said composition. Fillers also add
1011/PAT APPLN/10
11
mass and/or volume to the active ingredient in order to facilitate precise
measurement of the doses. Suitable carriers that can be used in the present
invention include, but not limited to, mineral oil, vegetable oil, china clay and so
forth.
The synergistic fungicidal composition of the present invention was found to be
non-phytotoxic and has good stability, wettability, suspensibility and
dispersibility.
It has been surprisingly found that the synergistic insecticidal composition of the
present invention provides a wide spectrum control of fungal pathogens, delaying
the appearance of the resistant strains of fungi, and achieving effective and
economical control of undesired fungi. Accordingly, there is provided a method
for controlling fungi, comprising contacting crops or their environment with a
fungicidally effective amount of the composition of the present invention, wherein
Propineb and Difenconazole are present in a ratio of about 16:1.
The present invention is more particularly described in the following examples
that are intended as illustrations only, since numerous modifications and
variations within the scope of the present invention will be apparent to those of
skill in the art. Unless otherwise noted, all parts, percentages, and ratios reported
in the following examples are on a weight basis and all reagents used in the
example were obtained or are available from the chemical suppliers.
EXAMPLES
The following examples illustrate embodiments of the proposed invention that are
presently best known. However, other embodiments can be practiced that are also
within the scope of the present invention. All of the agrochemical formulations,
according to the scope of the present invention and exemplified below had
excellent storage stability properties.
1011/PAT APPLN/10
12
Examples 1-6:
Synergistic fungicidal compositions
The unit of each value below is “% w/w” i. e. the percentage by weight, relative to
the weight of the total solution or composition unless otherwise specified. The
compositions contemplated by each of the Examples 1-3 that are tabulated in
Table 1 are formulated as Oil dispersions (OD).
Table 1: Examples of synergistic fungicidal composition as Oil-Dispersion
(OD)
S. No. Component Function
Example
1 2 3
1 Propineb A.I. 32.00 32.00 32.00
2 Difenoconazole A.I. 1.50 2.00 2.50
3
Ethoxylated Polyarylphenol
Phosphate Ester
Emulsifiers
cum
Dispersant
5.00-20.00
4
Sodium alkyl naphthalene
sulfonate blend
Wetting
Agent
0.00-15.00
5 Dimethyl Polysiloxane emulsion Defoamer 0.01-0.50
6 Rheology Modifier
Rheology
Modifier
0.10-3.00
7 Mineral/Vegetable Oil Filler Q.S.
A.I.= Active Ingredient
Q.S.= Quantity Sufficient
1011/PAT APPLN/10
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The unit of each value below is “% w/w” i. e. the percentage by weight, relative to
the weight of the total solution or composition unless otherwise specified. The
compositions contemplated by each of the Examples 4-6 that are tabulated in
Table 2 are formulated as Water dispersible granules (WDG or WG).
Table 2: Example of synergistic fungicidal combination as water dispersible
granules (WG or WDG)
S. No. Component Function
Example
4 5 6
1 Propineb A.I. 64.00 64.00 64.00
2 Difenoconazole A.I. 3.00 4.00 5.00
3
Mix. of sodium salt of
naphthalene sulfonate
condensate and sodium
lignosulfonate
Dispersing
Agent
1.00-15.00
4 Sodium Lauryl sulphate Wetting Agent 1.00-10.00
5 Dimethyl Polysiloxane Defoamer 0.01-0.50
6
Mix of Citric acid and Sodium
Bicarbonate
Disintegration
agent
0.10-5.00
7 China Clay Filler Q.S.
A.I.= Active Ingredient
Q.S. = Quantity sufficient
1011/PAT APPLN/10
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Process of Manufacturing of synergistic fungicidal composition:
The synergistic fungicidal composition(s) of Examples 1-3 are prepared by the
process (Process 1) described herein below. The raw materials required for
preparing Examples 1, 2 and 3 are illustrated in table 3 under the column headings
1, 2 and 3 respectively. Entries for Difenoconazole and Propineb in table 3 differ
from those in table 1 as entries in table 1 are for 100% pure compounds, whereas
those in table 3 are for technical ones, i.e. the ones containing a certain percentage
of impurities.
The amounts of active ingredients presented in table 3 may be greater than the
values calculated taking into account the percentage purity of the active
ingredients, to compensate for losses of said ingredients during the manufacturing
process. It was observed that following said procedure on industrial scale the final
yield of A.I. will be similar or same as to standardized values.
The process of manufacture for 100 kg batch size of fungicidal composition in the
form of an Oil dispersion (OD) comprising Propineb and Difenoconazole is as
follows.
Process 1:
a) The dispersing cum wetting agent and emulsifier are first diluted in oil and
solubilized by high shear mixing. Then, Difenoconazole technical, Propineb
Technical, and defoamer are added and mixed to form a homogeneous mass.
b) The above homogenous mass is ground in a Bead Mill until a mean particle
size of 3-5 (D-90) μ is obtained.
c) After the grinding, Rheology Modifier is added under low stirring to form a
final homogenous mass.
d) The final homogenous mass was tested for conformance to the laid out
specifications.
1011/PAT APPLN/10
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Table 3: Quantities of TGAI* and raw materials charged
S. No. Component Function Quantities of raw material
charged (kg/100 kg batch)
1 2 3
1
Propineb 85% w/w
min.
TGAI*
37.80 37.80 37.80
2
Difenoconazole 95%
w/w min.
TGAI*
1.60 2.12 2.63
3
Ethoxylated
Polyarylphenol
Phosphate Ester
Emulsifiers
cum
Dispersant
5.00 5.00 5.00
4
Sodium alkyl
naphthalene
sulfonate blend
Wetting Agent
2.00 2.00 2.00
5
Dimethyl
Polysiloxane
emulsion
Defoamer
0.20 0.20 0.20
6 Rheology Modifier
Rheology
Modifier
0.10 0.10 0.10
7
Mineral/Vegetable
Oil
Filler
53.30 52.78 52.25
* TGAI: Technical Grade Active Ingredient
The synergistic fungicidal composition(s) of Examples 4-6 are prepared by the
process (Process 2) described herein below. The raw materials required for
1011/PAT APPLN/10
16
preparing Examples 4, 5 and 6 are illustrated in table 4 under the column headings
4, 5 and 6 respectively. Entries for Difenoconazole and Propineb in table 4 differ
from those in table 2 as entries in table 2 are for 100% pure compounds, whereas
those in table 4 are for technical ones, i.e. the ones containing a certain percentage
of impurities.
The amounts of active ingredients presented in table 4 may be greater than the
values calculated taking into account the percentage purity of the active
ingredients, to compensate for losses of said ingredients during the manufacturing
process. It was observed that following said procedure on industrial scale the final
yield of A.I. will be similar or same as to standardized values.
The process of manufacture for 100 kg batch size of fungicidal composition in the
form of Water dispersible granules (WDG or WG) comprising Propineb and
Difenoconazole is as follows.
Process 2:
The required amounts of raw materials i.e. wetting agent, dispersing agent, fillers
and technicals (Table 4) were transferred in a mixing vessel.
The above mass was mixed in a blender along with sufficient quantity of water to
form a slurry. The slurry was ground in a Bead mill until a mean particle size of
below 10 (D-90) μ was obtained. After grinding, mix homogeneous slurry in
spray dryer by hot air and prepare granules and check for quality parameter.
Table 4: Quantities of TGAI*and raw materials charged
S. No. Component Function Quantities of raw material
charged (Kg/100 kg batch)
4 5 6
1
Propineb 85% w/w
min.
TGAI*
75.50 75.50 75.50
1011/PAT APPLN/10
17
2
Difenoconazole 95%
w/w min.
TGAI*
3.17 4.24 5.30
3
Mix. of sodium salt
of naphthalene
sulfonate condensate
and sodium
lignosulfonate
Dispersing
Agent
12.00 12.00 12.00
4
Sodium Lauryl
Sulphate
Wetting Agent
2.00 2.00 2.00
5
Dimethyl
Polysiloxane
Defoamer
0.20 0.20 0.20
6
Mix of Citric acid
and Sodium
Bicarbonate
Disintegration
agent
1.00 1.00 1.00
7 China Clay Filler 6.13 5.06 4.00
* TGAI: Technical Grade Active Ingredient
Comparative Evaluation of various ratios of the synergistic fungicidal
combination of Propineb and Difenoconazole against Powdery Mildew and
Downey Mildew in grape vines
Method & Time of Application
Field tests of the compositions according to the present invention were conducted
at various controlled trial sites. The performance of the fungicidal composition
prepared according to the present invention was compared against the known
compositions of Propineb and Difenoconazole, which were evaluated against
Powdery Mildew and Downey Mildew diseases in grape vines and also the
1011/PAT APPLN/10
18
vigour/yield of the crop was tested. The grape vines were pruned in October. The
required amount of fungicides were weighed and diluted with water to get the
stated concentration of the active compound and application was made using
backpack type sprayer fitted with pressure regulator and a vertical bar with one
hollow cone nozzle using a spray fluid of 200 L/acre. The spraying schedule was
initiated at the onset of visible disease incidence. Total of three treatments/sprays
were applied with an interval of fourteen (14) days. Experimental design was in
randomized blocks with five replications and each plot measured an area of 100
m2 (15 vines each plot). The intensity for disease severity was analysed at 7 and
14 days after each spray. Per cent disease index (PDI) was calculated by using
formula adopted by Horsfall and Heuberger, 1942* as follows:
The per cent disease index (PDI) was calculated by using the following formula,
PDI = Sum of all disease Ratings ____________________ x 100
Total no of leaves or fruits assessed x Maximum Disease rating
The per cent disease control (PDC) was calculated by the following formula
PDC= PDI in control – PDI in treatment______ x 100
PDI in Control
* Horsfall. J.G and J.W. Henberger. 1942. Measuring magnitude of defoliation
disease of tomatoes. Phytopath., 32: 226-232.
Table 5 Treatment details for evaluation of bio-efficacy of novel fungicidal
composition against fungal diseases in grape vines
Particular Treatment
A.I.
Percentage
Dose
(A.I
g/acre)
Dose (
formulation/
Acre)
T1 Propineb + Difenoconazole
OD
1.5 + 32 18 +
384
1200 ml
1011/PAT APPLN/10
19
T2 Propineb + Difenoconazole
OD
2 + 32 24 +
384
1200 ml
T3 Propineb + Difenoconazole
OD
2.5 + 32 30 +
384
1200 ml
T4 Propineb + Difenoconazole
WDG
3 + 64 18 +
384
600 gm
T5 Propineb + Difenoconazole
WDG
4 + 64 24 +
384
600 gm
T6 Propineb + Difenoconazole
WDG
5 + 64 30 +
384
600 gm
T7 Propineb 70% WP 70 420 600 gm
T8 Difenoconazole 25% EC 25 25 100 ml
T9 Untreated Control (Water
Spray)
- - -
A.I. = Active ingredient
The effectiveness of the individual and the combined treatment for control of
disease spectrum in Grape vines to demonstrate synergistic impact of Propienb
and Difenoconazole combinations @ different doses is given in Table 6 and 7.
1011/PAT APPLN/10
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Table 6: Effect of different combinations of Propienb and Difenoconazole on
Percent disease index (PDI) of Powdery Mildew and Downey Mildew diseases
in Grape vines
Treatments
Powdery Mildew on leaves (PDI)*
(Mean of 7 & 14 days after spray)
Downey Mildew on leaves (PDI)*
(Mean of 7 & 14 days after spray)
PTO
I spray
II spray
III spray
PTO
I spray
II spray
III spray T1 3.47
6.47
(14.73)b
10.23
(18.65)b
16.23
(23.75)c
11.32
9.20
(17.65)c
12.36
(20.58)b
17.52
(24.74)c
T2 3.57
4.37
(12.06)a
8.23
(16.67)a
11.37
(19.70)a
9.92
8.27
(16.71)c
11.80
(20.08)b
16.15
(23.69)b
T3 3.93
5.07
(13.01)ab
9.27
(17.72)ab
12.27
(20.50)a
b
10.06
8.39
(16.83)ab
11.03
(19.39)a
b
16.26
(23.77)b
T4 3.67 5.27
(13.27)b
9.72
(18.16)b
12.59
(20.78)b
9.74 8.65
(17.10)b
11.23
(19.57)a
16.20
(23.73)b
T5 3.85
3.22
(10.33)a
8.01
(16.44)a
9.20
(17.65)a
10.34
7.32
(15.69)a
10.13
(18.55)a
14.78
(22.60)a
T6 3.89
4.00
(11.53)a
8.27
(16.71)a
10.00
(18.43)a
10.29
7.56
(15.95)a
10.37
(18.78)a
15.48
(23.16)a
b
T7 3.90
13.35
(21.39)c
19.31
(26.06)c
23.98
(29.32)c
10.13
11.23
(19.57)ab
14.78
(22.60)a
23.67
(29.11)d
T8 3.78
7.56
(15.95)c
11.07
(19.43)c
15.23
(22.97)c
10.65
18.60
(25.54)c
30.69
(33.64)c
39.43
(38.89)c
T9 3.92
24.36
(29.57)d
29.77
(33.06)c
32.13
(34.53)c
10.09
28.23
(32.09)c
35.27
(36.43)c
47.50
(43.56)g
PTO- Pre Treatment Observation, PDI- Per cent Disease Index
* Mean of four replications
1011/PAT APPLN/10
21
Values in parentheses are arcsine-transformed values
In a column, means followed by a common letter are not significantly different at
the 5% level by DMRT.
Table 7: Effect of different combinations of Propienb and Difenoconazole on
Percent disease Control (PDC) of Powdery Mildew and Downey Mildew
diseases and Yield in Grape Vines
S. No
Treatments
Powdery Mildew
(PDC) (Mean of 7 &
14 days after spray)
Downey Mildew (PDC)
(Mean of 7 & 14 days
after spray)
Fruit
Yield*
(t acre-1)
I
spray
II
spray
III
spray
I
spray
II
spray
III
spray
1 T1 73.44 65.64 49.48 67.41 64.95 63.11 8.36
2 T2 82.06 72.35 64.61 70.27 68.72 65.76 9.24
3 T3 79.18 68.86 61.81 70.70 66.54 66.00 9.16
4 T4 78.36 67.34 60.81 69.35 68.15 65.89 8.96
5 T5 86.78 73.09 71.36 74.07 71.27 68.88 9.84
6 T6 83.57 72.22 68.87 73.21 70.59 67.41 9.78
7 T7 45.19 35.13 25.36 60.21 58.09 50.16 6.75
8 T8 68.96 62.81 52.59 34.11 12.98 16.98 7.10
9 T9 0.00 0.00 0.00 0.00 0.00 0.00 4.80
PDC: Percent disease control
t acre-1: tonnes per acre
It was surprisingly found that the Propienb and Difenoconazole WDG at 16:1 ratio
(T5) was significantly superior over other ratios at the same dose and also shows
much better control against major diseases when compared against commercial
formulations available in the market i.e. Propineb 70% WP and Difenoconazole
25% EC at recommended dose when applied three times at 14 days interval along
with significant increase in yield/hectare.
1011/PAT APPLN/10
22
At fourteen days after third spray the maximum disease incidence for powdery
mildew was observed in control i.e. 32.13 PDI and least in Propienb and
Difenoconazole WDG at a ratio of 16:1 i.e. 9.20 PDI with over 71.36% control.
Similarly, the maximum disease incidence for downy mildew was recorded in
control with 47.50 PDI against 14.78 PDI in Propienb and Difenoconazole WDG
at a ratio of 16:1 after third round of spraying with over 68% control.
Highest Grape fruit yield of 9.84 t/acre, recorded for treatment with Propienb and
Difenoconazole WDG at a ratio of 16:1, was significantly better than all other
treatments.
Thus it was concluded that Propienb and Difenoconazole WDG at a ratio of 16:1
ratio was found to be the best combination ratio over other tested combinations
and their commercial formulations at recommended doses to control Powdery
mildew and Downey mildew disease in Grape vines and to maximize the yield
potential.
The phytotoxic effect of different treatment schedules were also observed in ten
randomly selected plants from each plot on 0-10 scale (table 8) for yellowing,
stunting, necrosis, epinasty, hyponasty, etc. Observations were recorded on 1, 3, 7,
& 14 days after application and their mean values are presented in Table 9.
Table 8: Phytotoxicity visual scoring 0-10
Description of
crop
Rating Remarks
Description of
crop
Rating Remarks
No injury,
normal
0 Immune Severe injury,
no recovery
possible
6 Moderately
tolerant
Slight injury /
discoloration
1 Resistant Sever injury,
stand loss
7 Susceptible
1011/PAT APPLN/10
23
Some stand
crop, stunning /
discoloration
2 Moderately Almost
destroyed, a few
plants surviving
8 Susceptible
Injury more
pronounced but
not persistent
3 Tolerant Very few plants
alive
9 Highly
susceptible
Moderate
injury, recovery
possible
4 Tolerant Complete
destruction
10 Highly
susceptible
Injury more
persistent,
recovery more
doubtful
5 Moderately
tolerant
Table 9: Phytotoxic Effect of Different Treatments on Grape Vines
Treatments
Phytotoxicity ratings*
Leaf injury Wilting Vein clearing
R1 R2 R3 R1 R2 R3 R1 R2 R3
T1 0 0 0 0 0 0 0 0 0
T2 0 0 0 0 0 0 0 0 0
T3 0 0 0 0 0 0 0 0 0
T4 0 0 0 0 0 0 0 0 0
T5 (Propineb and
Difenoconazole WDG)
0 0 0 0 0 0 0 0 0
T6 0 0 0 0 0 0 0 0 0
T7 0 0 0 0 0 0 0 0 0
T8 0 0 0 0 0 0 0 0 0
1011/PAT APPLN/10
24
T9 0 0 0 0 0 0 0 0 0
*Observed on 1, 3, 7, & 14 days after spraying and the mean values are presented
R = Replications
From the foregoing it will be observed that numerous modifications and variations
can be effectuated without departing from the true spirit and scope of the novel
concepts of the present investigation. It is to be understood that no limitations with
respect to the specific embodiment illustrated is intended or should be inferred. It
should be understood that all such modifications and improvements have been
deleted herein for the sake of conciseness and readability but are properly within
the scope of the following claims.
1011/PAT APPLN/10
25

We Claim
1. A synergistic fungicidal composition, comprising Difenoconazole and
Propineb.
2. The synergistic fungicidal composition, as claimed in claim 1, wherein
Difenoconazole and Propineb are present in a mass ratio in the range from
1:6.4 to 1:43.
3. The synergistic fungicidal composition, as claimed in claim 2, wherein the
mass ratio of Difenoconazole to Propineb is preferably 1:16.
4. The synergistic fungicidal composition, as claimed in claims 1 to 3,
wherein Propineb is present in an amount in the range from 32 to 64% and
Difenoconazole is present in an amount in the range from 1.5 to 5%.
5. The synergistic fungicidal composition, as claimed in claims 1 to 4, further
comprising excipients; wherein the composition is in the form of an
emulsion concentrate (EC), a suspo-emulsion (SE), a micro-emulsion
(ME), an oil-dispersion (OD), a capsulated suspension (CS), a water
dispersible granule (WG or WDG), or a suspension concentrate (SC).
6. The synergistic fungicidal composition, as claimed in claim 5, wherein the
excipients are selected from the group consisting of an emulsifier cum
dispersant, a dispersing agent, a wetting agent, a defoamer, a rheology
modifier, a disintegration agent, a filler and combinations thereof, and
wherein the composition may be in the form of an oil dispersion (OD) or a
water dispersible granule (WDG or WG).
7. The synergistic fungicidal composition as claimed in claim 6, wherein the
emulsifier cum dispersant or dispersing agent is preferably ethoxylated
polyarylphenol phosphate ester, or a mixture of sodium salt of naphthalene
sulfonate condensate and sodium lignosulfonate and present in an amount
in the range from 1 to 20%.
8. The synergistic fungicidal composition as claimed in claim 6, wherein the
wetting agent is preferably sodium lauryl sulfate or a sodium alkyl
naphthalene sulfonate blend and present in an amount in the range from 0
to 15%.
1011/PAT APPLN/10
26
9. The synergistic fungicidal composition as claimed in claim 6, wherein the
defoamer is preferably dimethyl polysiloxane emulsion and present in an
amount in the range from 0.01 to 0.50%.
10. The synergistic fungicidal composition as claimed in claim 6, wherein the
rheology modifier is present in an amount in the range from 0.10 to 3.00%.
11. The synergistic fungicidal composition as claimed in claim 6, wherein the
disintegration agent is preferably a mixture of citric acid and sodium
bicarbonate, and present in an amount in the range from 0.10-5.00%.
12. The synergistic fungicidal composition, as claimed in any of the claims 1
to 11, wherein the composition is non-phytotoxic and has good stability,
wettability, suspensibility and dispersibility.