DESC:FIELD OF INVENTION
The invention relates to a composition, comprising difenoconazole and a fungicidally active chemical compound and also a method for curatively or preventively controlling the phytopathogenic fungi of plants.
BACKGROUND OF THE INVENTION
The control of plant diseases caused by fungal plant pathogens is extremely important in achieving high crop efficiency. 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.
Fungicides are compounds, of natural or synthetic origin, which act to protect plants against damage caused by fungi. Current methods of agriculture rely heavily on the use of fungicides. Using fungicides may allow a grower to increase the yield and the quality of the crop and consequently, increase the value of the crop. Generally, a single fungicide may not be effective in all situations and repeated usage of a single fungicide may lead to the development of resistance to that specific fungicide and related fungicides. Consequently, research is conducted to produce fungicides and combinations of fungicides that are efficacious, have superior performance, require lower dosages, are easier to use, and cost less.
A combination of mixture of two or more fungicides may yield results unexpectedly superior to that of the individual components. This synergism occurs when the activity of two or more compounds exceeds the activities of the compounds when used alone. The advantages of particular fungicide combinations are recognized in the art to vary, depending on such factors as the particular plant species and plant disease to be treated, and whether the plants are treated before or after infection with the fungal plant pathogen. 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-than-additive (i.e. synergistic) effect to provide commercially important levels of plant disease control.
In view of the above, obtaining a fungicidal combination which demonstrates no cross-resistance to the existing fungicidal agents, no toxicity problems and little negative impact on the environment is extremely difficult.
Difenoconazole (IUPAC name: cis,trans-3-chloro-4-[4-methyl-2-(1H-1,2,4-1-ylmethyl)-1,3-dioxolan-2-yl]phenyl 4-chlorophenyl ether) is a fungicide.
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; The British Crop Protection Council] under the entry number 266. 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, ornamentals and vegetable crops. It has preventive and curative action.
Difenoconazole is absorbed by the leaves with acropetal and strong translaminar translocation and acts by inhibition of sterol demethylation during cell membrane ergosterol biosynthesis thereby stopping development of fungus. Despite being a broad spectrum fungicide its phytotoxic effects or phytotoxicity was reported in literature, e.g., F. Montfort et al., Pesticide Science 46(4), 1996, 315-322, reported 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 gibberellin for reducing or preventing the phytotoxic effect of azole fungicides or of azole fungicides used in combination with anilide fungicides, primarily for seed treatment.
Mancozeb (IUPAC name: manganese ethylenebis(dithiocarbamate) (polymeric) complex with zinc salt) is a dithiocarbamate fungicide developed from two other dithiocarbamates: maneb and zineb and first reported in Fungic. Nematic. Tests, 1961, 17.
Mancozeb has a polymeric structure containing 2.2 percent zinc, in which 6 percent of the units are in the form of a coordination complex. Mancozeb is essentially inert to oxidation by atmospheric oxidation, in contrast to maneb. It is also essentially non- phytotoxic in contrast with maneb, zineb or mixtures of these which are harmful to a number of plants. It is known to act by reacting with and inactivating the sulfhydryl groups of amino acids and enzymes of fungal cell, resulting in disruption of lipid metabolism, respiration and production of adenosine triphosphate (ATP). Mancozeb is a broad spectrum, non-systemic fungicide with protective action. It is widely used for control of many fungal diseases in a wide range of crops, fruits, nuts, vegetables, ornaments for control of early and late blight, downey mildew, scab, rot etc.
The standard composition of mancozeb available in the art is 80 percent wettable powder containing 16% manganese and 2% zinc. However, there are many disadvantages associated with the use of a powder composition. For example, US patent No. 5,001,150 discloses removal of disadvantages associated with powder composition and teaches a non-dusty spray dried Mancozeb water dispersible granules (WDG) and the process for their production.
The use of fungicide combinations is a widespread and documented practice in the agricultural community. 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 most-efficacious and synergistic ratios of difenoconazole and mancozeb, at which ratio these fungicides synergistically complement each other's fungicidal properties not seen at other ratios.

SUMMARY OF THE INVENTION
The invention relates to a composition, comprising Difenoconazole and a fungicidally active chemical compound.
In accordance with an embodiment of the invention, there is provided a synergistic fungicidal composition comprising difenoconazole and mancozeb.
In accordance with another embodiment of the invention, there is provided a synergistic fungicidal composition comprising difenoconazole and mancozeb in a ratio of 1:3 to 1:7.
In accordance with another embodiment of the present invention, the synergistic fungicidal composition may be formulated as dust, powder, granules, pellets, tablets, dry flowable, wettable powder, water dispersible granules or liquid.
According to an embodiment of the present invention, the synergistic fungicidal composition is preferably formulated as Water Dispersible Granules (WDG) and Wettable Powder (WP).
In accordance with another embodiment of the invention, there is provided a synergistic fungicidal composition further comprising at least one dispersing agent, at least one wetting agent, at least one anti-caking agent, and at least one filler to form a wettable powder or a water dispersible granule.
According to another embodiment of the present invention, there is provided a process of preparing a synergistic fungicidal composition, comprising the steps of: (a) admixing wetting agent, dispersing agent, anti-caking agent and filler in a mixing vessel to form a first mixture; (b) homogenizing the first mixture to a powder; (c) admixing said powder, and active ingredients to form a second mixture; (d) extruding the second mixture in the form of granules; and (e) drying the granules to obtain water dispersible granules.
In accordance with yet another embodiment of the invention, there is provided a process for preparing a synergistic fungicidal composition, comprising the steps of: (a) admixing difenoconazole, mancozeb, a wetting agent, a dispersing agent, an anti caking agent and a filler in a mixing vessel to form a mixture, and (b) homogenizing the mixture to a wettable powder.
In accordance with an embodiment of the invention, there is provided a process for controlling pathogenic fungi at a locus comprising treating the locus with the composition comprising difenoconazole and mancozeb.
The synergistic fungicidal combination of the present invention is found to be useful in protecting a wide range of crops against major diseases like late and early blight, powdery and downy mildew, blast, blight, rot etc. The composition achieves improved biological activity by enhancing overall control of fungus over a shorter period of time.
DETAILED DESCRIPTION OF THE INVENTION
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, 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 the terms of “% w/w” means the percentage by weight, relative to the weight of the total composition unless otherwise specified.
As used herein DF formulation, WDG formulation, WP formulation, SC formulation are the international denominations adopted by the FAO (Food and Agriculture Organization of the United Nations) to designate dry flowable, water dispersible granules, wettable powder and suspension concentrate, respectively.
The term "agrochemically effective amount" is that quantity of active agent, applied in any amount which will provide the required control of pest 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.
Many newer and conventional molecules are used for different pest management in chilli, but the indiscriminate use of these chemicals resulted in reduced control due to build-up of the resistance in targeted diseases. There are many reports on resistance of different diseases for different molecules. For example, Jose Luis Henríquez S. et al., Chilean Journal of Agricultural Research, 71(1), 39-44, reported that the use of fenarimol has considerably higher resistant to diseases in chilli among different fungicides. Similarly, B. V. Sallato and B. A. Latorre, in APS Journals (Published by: The American Phytopathological Society), March 2006, Volume 90, Number 3, Page 375 showed resistance of kresoxim-methyl in Venturia inaequalis (Cooke) winter isolates from apple scab.
In view of the above, obtaining a fungicidal combination which demonstrates no cross-resistance to the existing fungicidal agents, no toxicity problems and little negative impact on the environment is extremely difficult. Thus, it is an objective of this invention to provide a synergistic fungicidal composition which demonstrate a high controlling effect along with reduced crop protection cost and reduced environmental load. Accordingly, there is provided a novel synergistic fungicidal composition comprising Difenoconazole and a fungicidally active compound named mancozeb. There is also provided a novel synergistic fungicidal composition, wherein difenoconazole and mancozeb are present in a ratio of 1:3 to 1:7 and more preferably in a ratio of about 1:5. The total weight of difenoconazole and mancozeb together is about 60% by weight of the composition. Thus, a composition of the present invention comprises about 10.00% by weight of difenoconazole and 50.00% by weight of mancozeb. Such a fungicidal composition is useful for effectively controlling early and late blight, powdery and Downey mildew, die back and rot control and also enhances the vigor/yield of the plant. The synergistic fungicidal composition is also non-phytotoxic.
The synergistic fungicidal combination further comprises at least one dispersing agent, at least one wetting agent, at least one anti-caking agent, and at least one filler. The synergistic fungicidal composition may be formulated as dust, powder, granules, pellets, tablets, dry flowable, wettable powder, water dispersible granules or liquid and more preferably as Water Dispersible Granules (WDG) and Wettable Powder (WP). There is also provided a method of preparing Wettable Powder (WP) for a synergistic fungicidal combination comprising the step of admixing difenoconazole, mancozeb, wetting agent, dispersing agent, anti-caking agent and filler.
The synergistic fungicidal combination of the present invention is found to be useful in protecting a wide range of crops like fruits, vegetables, paddy, wheat etc. against major diseases like late and early blight, powdery and downy mildew, blast, blight, rot etc. The composition achieves improved biological activity by enhancing overall control of fungus over a shorter period of time. Additional benefits of using the fungicidal composition of the present investigation include reduced risk of occupational hazard, lower cost of application, better cost:benefit ratio to the end user, reduced fuel and labour cost, savings in applicator’s time and reduced wear of equipment and loss caused by mechanical damage to the crop and soil.
The present invention is more particularly described in the following examples that are intented 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 reagent used in the example were obtained or are available from the chemical suppliers.
Example 1-5:
Synergistic fungicidal composition of Difenoconazole and Mancozeb
The unit of each value below is “% w/w”, i.e., percentage weight by weight, relative to the weight of the composition unless otherwise specified. The compositions tabulated in each of the example 1 – 5 that are tabulated in Table 1 are formulated as wettable powder (WP).
Table 1: Examples of Synergistic fungicidal composition of Difenoconazole and Mancozeb
Component Function Examples (% w/w)
1 2 3 4 5
Difenoconazole A.I. 8.00 9.00 10.00 12.00 15.00
Mancozeb A.I. 56.00 54.00 50.00 48.00 45.00
Condensate of Formaldehyde and naphthalene sulfonic acid sodium salt Wetting Agent 3.00 3.00 3.00 3.00 3.00
Stearyl-benzimidazol disulfonic acid Dispersing Agent 3.00 3.00 3.00 3.00 3.00
Silica Anti-caking Agent 2.20 2.20 2.20 2.20 2.20
Kaolin Filler q.s. q.s. q.s. q.s. q.s.
A.I.= Active Ingredient
q.s.= quantity Suffucient
Example 6
Process of Manufacturing of synergistic fungicidal combination of Difenoconazole and Mancozeb:
The noval fungicide composition of Example 1-5 are prepared by the process described hereinafter. The process of manufacture 100 kg batch size of fungicidal composition comprising Difenoconazole and Mancozeb is provided.
Process 1: Method of preparing Water Dispersible Granule (WDG) for a novel synergistic fungicidal composition comprising Difenoconazole and Mancozeb
The wetting agent, dispersing agent, anti-caking agent and filler (Table 2) were charged in a pre-blender and mixed for 30 minutes. The mixture was milled with an air classifier mill (ACM) to form a fine powder. The powder was collected in a post blender and mixed for 30 minutes and thereafter this powder was transferred to a dough mixer. Required quantities of Difenoconazole and Mancozeb (Table 2) were sprayed onto the powder to get dough. The dough was transferred to basket extruder by maintaining the temperature of extruder below 700C. Start granulation of the dough with an extruder. Dry the granules at 700C. Subsequently, the samples were further tested for quality parameters for confirmation to the laid down specification and packed as per requirement after approval.
Process 2: Method of preparing Wettable Powder (WP) for a novel synergistic fungicidal composition comprising Difenoconazole and Mancozeb
The required amounts of Difenoconazole and Mancozeb (Table 2) are transferred in pre-blender with condensate of formaldehyde and naphthalene sulfonic acid sodium salt (wetting agent), stearyl-benzimidazol disulfonic acid (dispersing agent), silica (anti caking agent), kaolin (filler) as per table 2 below and blended for one hour in a high speed blender. The mixture is homogenized using colloid mill and sieved (1000 micron) to remove course particles. The mixture is transferred to post blender and further blended for one hour. Subsequently, the sample is further tested for quality parameters for confirmation to the laid down specification and packed as per requirement after approval.
Table 2: Quantities of technical and raw materials charged
Component Function Quantities of raw material charged (Kg/100 kg batch)
1 2 3 4 5
Difenoconazole Technical (purity 95% w/w) Active Ingredient 8.45 9.48 10.57 12.68 15.80
Mancozeb Technical (purity 85.% w/w) Active Ingredient 65.90 63.54 58.86 56.53 52.95
Condensate of Formaldehyde and naphthalene sulfonic acid sodium salt Wetting Agent 3.00 3.00 3.00 3.00 3.00
Stearyl-benzimidazol disulfonic acid Dispersing Agent 3.00 3.00 3.00 3.00 3.00
Silica Anti-caking Agent 2.20 2.20 2.20 2.20 2.20
Kaolin Filler 17.45 18.78 22.37 22.59 23.05

Example 7
Comparative Evaluation of various ratios of the synergistic fungicidal combination of Difenoconazole and Mancozeb against Rot (Fruit/Ripe)/Die back (Colletotrichum capsici); and Powdery mildew (Levillula taurica) in Chilli crop
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 compositions prepared as described in example 6 according to the present invention was compared against the known compositions of Mancozeb and Difenoconazole, which were evaluated against Rot (Fruit/Ripe)/Die back (Colletotrichum capsici); and Powdery mildew (Levillula taurica) in Chilli, and the vigor/yield of the crop was determined. The Chilli plants were transplanted in field and harvested after 128 days. 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 a pressure regulator and a vertical bar with one hollow cone nozzle using a spray fluid at the rate of 200 L/acre. Experiments were carried out in randomized blocks with five replicates and each plot measured 120 sq. m. (12 x 10 m). The disease intensity for powdery mildew was analysed at 7 and 14 days after each spray and for fruit rot and die back analysed at harvest. Per cent disease index (PDI) was calculated by using formula adopted by Horsfall and Heuberger, 1942 as follows
PDI = Sum of all disease Ratings _______________x 100
Total no of leaves/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
Table 3 below summarizes the individual and combined treatments for disease spectrum at different concentrations of difenoconazole and mancozeb.
Table 3 Treatment details for evaluation of bio-efficacy of novel fungicidal composition against fungi on chilli crop
Particular Treatment A.I. Percentage Dose (a.i gm/acre) Volume of formulation (gm/ml)
T1 Difenoconazole + Mancozeb (1:7) 8 + 56 20 + 140 250
T2 Difenoconazole + Mancozeb (1:6) 9 + 54 22.5 + 135 250
T3 Difenoconazole + Mancozeb (1:5) 10 + 50 25 + 125 250
T4 Difenoconazole + Mancozeb (1:4) 12 + 48 30 + 120 250
T5 Difenoconazole + Mancozeb (1:3) 15 + 45 37.5 + 112.5 250
T6 Difenoconazole 25% EC 25.00% 25 100
T7 Mancozeb 75% WP 75.00% 600 800
T8 Untreated Control - - -

The effectiveness of the individual and the combined treatment for control of disease spectrum for chilli crop at different combinations of Difenoconazole and Mancozeb to demonstrate synergistic impact of Difenoconazole + Mancozeb combinations @ 250 gm/acre is given in Table 4-6.
Table 4: Effect of different combinations of Difenoconazole and Mancozeb on Percent disease index (PDI) and Percent disease control (PDC) of Powdery mildew in Chilli crop
Treat Treatment Details Dose (gm/ml/ Acre) Powdery Mildew (PDI) (Mean of 7 & 14 days after spray)* Powdery Mildew (PDC) (Mean of 7 & 14 days after spray)
Before 1st Spray After 1st spray After2nd spray After 3rd spray After 1st spray After2nd spray After 3rd spray
T1 Difenoconazole 8% + Mancozeb 56% WP (1:7) 250 09.02 13.33
(21.41) 17.67
(24.86) 19.23
(26.01) 52.95 55.05 67.59
T2 Difenoconazole 9% + Mancozeb 54% WP (1:6) 250 09.45 11.61
(19.92) 14.00
(21.97) 16.62
(24.06) 59.02 64.39 71.99
T3 Difenoconazole 10% + Mancozeb 50% WP (1:5) 250 08.12 8.14
(16.58) 9.00
(17.46) 10.01
(18.44) 71.27 77.11 83.13
T4 Difenoconazole 12% + Mancozeb 48% WP (1:4) 250 09.40 13.00
(21.13) 15.67
(23.32) 17.49
(24.72) 54.11 60.14 70.52
T5 Difenoconazole 15% + Mancozeb 45% WP (1:3) 250 08.45 12.67
(20.85) 14.10
(22.06) 16.00
(23.58) 55.28 64.13 73.03
T6 Difenoconazole 25% EC 100 08.00 13.50
(21.56) 17.89
(25.02) 20.09
(26.63) 52.35 54.49 66.14
T7 Mancozeb 75% WP 800 08.08 17.83
(24.98) 23.39
(28.92) 27.67
(31.74) 37.06 40.50 53.36
T8 Untreated Control - 09.10 28.33
(32.16) 39.31
(38.83) 59.33
(50.38) 0.00 0.00 0.00
S. Em.+ - 0.35 0.25 0.28 - -
CD (P=0.05) NS 1.07 0.74 0.84 - -
* Figures in parenthesis indicate angular transformations.
It was surprisingly found that Difenoconazole + Mancozeb at 1:5 ratio was significantly superior over other ratios i.e. 1:7; 1:6; 1:4; & 1:3 at the same dose and also shows much better control against powdery mildew, rot and die back disease when compared against commercial formulations available in the market for Difenoconazole 25% EC and Mancozeb 75% WP at recommended dose, when applied three times at 15 days interval along with significant increase in fruits/ plant and yield/hectare.
At fifteen days after third spray the maximum disease incidence was observed in control i.e. 59.33 PDI and least in Difenoconazole + Mancozeb at 1:5 ratio i.e. 10.01 PDI with over 83% control.

Table 5: Effect of different combinations of Difenoconazole and Mancozeb on Percent Fruit damage and Percent disease control (PDC) due to Rot and Die Back on Chilli Fruits
Treat Treatment Details Dose (gm/ml/ Acre) Fruit Rot Damage (%) * Percent Control (%)
1st Picking 2nd Picking 1st Picking 2nd Picking
T1 Difenoconazole 8% + Mancozeb 56% WP (1:7) 250 13.23
(21.33) 15.85
(23.46) 68.50 69.12
T2 Difenoconazole 9% + Mancozeb 54% WP (1:6) 250 10.23
(18.65) 12.00
(20.27) 75.64 76.62
T3 Difenoconazole 10% + Mancozeb 50% WP (1:5) 250 7.67
(16.08) 8.00
(16.43) 81.74 84.41
T4 Difenoconazole 12% + Mancozeb 48% WP (1:4) 250 11.23
(19.58) 13.96
(21.94) 73.26 72.80
T5 Difenoconazole 15% + Mancozeb 45% WP (1:3) 250 10.12
(18.55) 13.23
(21.33) 75.90 74.23
T6 Difenoconazole 25% EC 100 13.52
(21.57) 15.5
(23.18) 67.81 69.80
T7 Mancozeb 75% WP 800 18.67
(25.60) 23.23
(28.81) 55.55 54.74
T8 Untreated Control - 42.00
(40.40) 51.33
(45.76) - -
S. Em.+ 0.41 0.30 - -
CD (P=0.05) 1.24 0.92 - -
* Figures in parenthesis indicate angular transformations.
The maximum damaged fruits % due to rot/die back was recorded in control with 42.00% and 51.33% damaged fruits respectively during first and second picking against 7.67% and 8.00% damaged fruits in difenoconazole and mancozeb at 1:5 ratio during first and second picking with over 80% control.
Table 6: Effect of different combinations of Difenoconazole and Mancozeb on Yield attributes on Chilli crop
Treat Treatment Details Dose (gm/ml/ Acre) No. of fruits/plant
(**) Yield (qt/acre)
Increase in yield over control (%)
T1 Difenoconazole 8% + Mancozeb 56% WP (1:7) 250 10.25 28.88 60.12
T2 Difenoconazole 9% + Mancozeb 54% WP (1:6) 250 11.00 29.68 64.58
T3 Difenoconazole 10% + Mancozeb 50% WP (1:5) 250 13.33 33.01 83.03
T4 Difenoconazole 12% + Mancozeb 48% WP (1:4) 250 11.67 30.66 70.04
T5 Difenoconazole 15% + Mancozeb 45% WP (1:3) 250 12.00 31.00 71.88
T6 Difenoconazole 25% EC 100 9.67 28.35 57.17
T7 Mancozeb 75% WP 800 8.19 24.58 36.33
T8 Untreated Control - 6.89 18.03 -
S. Em.+ 0.34 0.49 -
CD (P=0.05) 1.03 1.49 -
Highest chilli fruit yield of 33.01 qt/acre was recorded in treatment of difenoconazole + mancozeb at 1:5 ratio which was significantly better than all other treatments.
Thus it was concluded that Difenoconazole + Mancozeb at 1:5 ratio was found to be the best combination over other tested rations viz., 1:7; 1:6; 1:4; & 1:3 and their commercial formulations at recommended doses to control powdery mildew, rots and die back disease in chilli crop and to maximize the yield potential.
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.

CLAIMS:
1. A synergistic fungicidal composition comprising difenoconazole and mancozeb in a ratio of 1:3 to 1:7.
2. The synergistic fungicidal composition as claimed in claim 1, wherein difenoconazole is present in an amount in the range from 8-15% w/w.
3. The synergistic fungicidal composition as claimed in claim 1, wherein mancozeb is present in an amount in the range from 45-56% w/w.
4. The synergistic fungicidal composition as claimed in claims 1-3, wherein the combined weight of difenoconazole and mancozeb is 60% w/w.
5. The synergistic fungicidal composition as claimed in claims 1-4, wherein the composition is formulated as dust, powder, granules, pellets, tablets, dry flowable, wettable powder, water dispersible granules or liquid.
6. The synergistic fungicidal composition as claimed in claims 1-5, wherein the composition further comprises a wetting agent, a dispersing agent, an anti-caking agent and a filler to form a wettable powder or a water dispersible granule.
7. A method for controlling pathogenic fungi at a locus, said method comprising treating the locus with the composition as claimed in claims 1-6.