WO2023042225A1

WO2023042225A1 - Fungicide composition comprising pyridine carboxamide, strobilurin and dithiocarbamate

Info

Publication number: WO2023042225A1
Application number: PCT/IN2022/050831
Authority: WO
Inventors: Aminul Islam; Balram BHAVANI; Kiran Pawar; Nikumbhe SAGAR DEVIDAS; Jaison JOYAL DSOUZA; Rajul EDOLIYA; Rajan KUMAR TRIVEDI; Ramakant PATIL
Original assignee: Coromandel International Limited
Priority date: 2021-09-17
Filing date: 2022-09-16
Publication date: 2023-03-23

Abstract

The present invention relates to novel fungicidal composition for protecting crops against fungal diseases, and the corresponding methods of protection by application of the said composition. Particularly, the present invention relates to fungicidal composition comprising pyridine carboxamide, strobilurin and dithiocarbamate. More, particularly the fungicidal composition relates to Boscalid, Azoxystrobin and Mancozeb.

Description

FUNGICIDE COMPOSITION COMPRISING PYRIDINE CARBOXAMIDE, STROBILURIN AND DITHIOCARBAMATE

FIELD OF THE INVENTION [001] The present invention relates to novel fungicidal compositions for protecting crops against fungal diseases, and the corresponding methods of protection by application of the said compositions. Particularly, the present invention relates to fungicidal compositions comprising pyridine carboxamide, strobilurin and dithiocarbamate. More, particularly the fungicidal composition relates to Boscalid, Azoxystrobin and Mancozeb.

BACKGROUND OF THE INVENTION

[002] Diseases are a common occurrence on plants, often having a significant economic impact on yield and quality, thus managing diseases is an essential component of production for most crops. Broadly, there are three main reasons that fungicides are used: (a) to control a disease during the establishment and development of a crop, (b) to increase productivity of a crop and to reduce blemishes, (c) to improve the storage life and quality of harvested plants and its products. Fungi often spoil (render unusable) stored fruits, vegetables, tubers, and seeds. Attempts have been made to control the fungal attack on plants by using different fungicides.

[003] 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. In fact, some crops cannot be grown usefully without the use of fungicides. Using fungicides allows a grower to increase the yield and the quality of the crop, and consequently, increase the value of the crop. In most situations, the increase in value of the crop is worth at least three times the cost of the use of the fungicide.

[004] Various compositions have been developed to control fungi and in practice have been used as a single or a mixed agent. Practical agricultural experience has shown that the repeated and exclusive application of an individual active compound in the control of harmful fungi leads in many cases to a rapid selection of those fungus strains which have developed natural or adapted resistance against the active compound in question. Effective control of these fungi with the active compound in question is very difficult in such cases. Active compounds having different mechanisms of action are combined to delay the generation of resistance and reduce the application amount and prevention and treatment costs. Consequently, research is being conducted to produce fungicides and combinations of fungicides that are safer, that have better performance, that require lower dosages, that are easier to use, and that cost less. [005] The present invention aims to provide one such combination of fungicides Boscalid, Azoxystrobin and Mancozeb providing broader control spectrum at lower dosages.

SUMMARY OF THE INVENTION

[006] The present invention provides a novel fungicidal composition comprising: a pyridine carboxamide fungicide; a strobilurin fungicide; a dithiocarbamate fungicide in effective amounts, along with suitable adjuvants.

[007] In an embodiment of the present invention, a novel fungicidal composition is provided comprising Boscalid, a pyridine carboxamide; Azoxystrobin, a strobilurin; and Mancozeb, a dithiocarbamate and adjuvants. [008] In an embodiment of the present invention, Boscalid is present in a range from 10% to 20% w/w, Azoxystrobin is present in a range from 12% to 20% w/w and Mancozeb is in a range from 45% to 49% w/w.

[009] In an embodiment of the present invention adjuvants are selected from the group comprising wetting agent, dispersing agent, adjuvant and filler. [010] In an embodiment of the present invention the wetting agent is selected from the group comprising naphthalene alkyl aryl sulphonate, dioctyl sulfosuccinate, sodium lauryl sulfate, non-ionic ethoxylated polyarylphenol phosphate ester, sodium alkyl naphthalene sulfonate, dialkyl naphthalene sulphonate sodium salt, alkylnaphthalene sulfonate (ANS) condensate blend, linear alcohol derivative and polyethylene glycol nonyl phenyl ether ammonium sulfate or a combination thereof present in an amount of 1 to 3% (w/w).

[Oil] In an embodiment of the present invention the dispersing agent is selected from the group comprising Sodium salt of methyl naphthalene sulfonate, Sodium ligno sulphonate, acrylate copolymer, phenol sulfonic acid-formaldehyde- polycondensation as sodium salt, sodium polycarboxylate, sodium methyl oleoyl taurate and sodium lauryl sulphate present in a range from 1% to 9% w/w.

[012] In an embodiment of the present invention the adjuvant is selected from the group comprising of amino acids (preferably 1-glutamate), trisiloxane ethoxylate, polyoxyethylene sorbitol ester, poly alkyleneoxide modified heptamethyl trisiloxane, and microfibrillated cellulose or a combination thereof present in an amount of 3% to 11% w/w.

[013] In an embodiment of the present invention the filler is selected from the group comprising aluminium silicate, com starch, lactose monohydrate, calcium carbonate, present in a range from 12% to 19% w/w.

[014] In an embodiment of the present invention the composition is formulated as Wettable powder.

DESCRIPTION OF THE INVENTION [015] The following detailed description is presented to enable any person skilled in the art to make and use the invention. For purposes of explanation, specific nomenclature is set forth to provide a thorough understanding of the present application. However, it will be apparent to one skilled in the art that these specific details are not required to practice the invention. Descriptions of specific applications are provided only as representative examples. The present application is not intended to be limited to the embodiments shown but is to be accorded the widest possible scope consistent with the principles and features disclosed herein.

[016] It is to be noted that, as used in the specification, 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.

[017] Similarly, the words "comprise," "comprises," and "comprising" are to be interpreted inclusively rather than exclusively. Likewise, the terms "include," "including" and "or" should all be construed to be inclusive, unless such a construction is clearly prohibited from the context. However, the embodiments provided by the present disclosure may lack any element that is not specifically disclosed herein. Thus, a disclosure of an embodiment defined using the term "comprising" is also a disclosure of embodiments "consisting essentially of’ and "consisting of’ the disclosed components. Where used herein, the term "example," particularly when followed by a listing of terms, is merely exemplary and illustrative, and should not be deemed to be exclusive or comprehensive. Any embodiment disclosed herein can be combined with any other embodiment disclosed herein unless explicitly indicated otherwise. [018] 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.

[019] The term “active ingredient” (a.i.) or “active agent” used herein refers to that component of the composition responsible for control of fungal diseases in plants and vegetation.

[020] As used herein, the term "effective amount" means the amount of the active substances in the compositions to achieve an observable effect on growth, including the effects of necrosis, death, retardation, prevention, and removal, destruction, or otherwise diminishing the occurrence and activity of the target organism. An effective amount of the compositions will also vary according to the prevailing conditions such as desired pesticidal effect and duration, weather, target species, locus, mode of application, and the like.

[021] This invention relates to a novel fungicidal composition comprising boscalid, azoxystrobin and mancozeb. The present invention also relates to use of such compositions in preventing fungal diseases in plants. [022] Boscalid (2-chloro-/V-(4'-chloro[l, 1 '-biphenyl]-2-yl)-3-pyridine carboxamide) is a member of the fungicide group succinate dehydrogenase inhibitors (SDHI) and is used worldwide in several crops for the control of a broad range of important pathogens. Boscalid is active against different fungal stages both on the plant surface and in the plant tissue. After application to the plant, the active ingredient is taken up via the leaf and then translocated via the transpiration flow. Due its mobility, it shows local systemic and translaminar activity. By that, it can control fungal stages, which have already become established in deeper tissue layers. As a result, Boscalid has preventative and curative activity. [023] Boscalid is active against different fungal stages on and in the plant. When applied protectively, boscalid inhibits spore germination and further development of germinated fungal spores. Boscalid is a pyridine carboxamide fungicide which is effective under preventative and curative conditions. Boscalid mode of action at the molecular level is the inhibition of the enzyme succinate dehydrogenase (SDH), also known as complex II in the mitochondrial electron transport chain. The structural formula of Boscalid is

[024] Azoxy strobin (methyl (E)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-a-

(methoxymethylene)benzeneacetate) is derived from naturally occurring strobilurins, highly effective phytotoxic compounds produced by two species of mushrooms found naturally in Czech forests. Azoxy strobin can be applied as a foliar spray or a soil-treatment prior to planting, as it has a residual effect. It acts as a systemic fungicide which has curative, translaminar and preventative action. The mode of action of azoxy strobin is to prevent the respiration of fungi due to the disruption of electron transport chain, preventing ATP synthesis (this occurs as the azoxystrobin binds to the Q_o site of Complex III within the mitochondrion). Azoxystrobin has the broadest spectrum of any antifungal treatment, and it is effective against all 4 major groups of fungi - the Ascomycota, Deuteromycota, Basidiomycota and the Oomycota. It is therefore able to prevent or cure powdery mildew, downy mildew, rust and rice blast diseases. Azoxystrobin is sold in the formulation of water dispersible granules and as a suspension concentrate in several concentrations. It is mostly used alone, although azoxystrobin can be combined with chlorothalonil, fenpropimorph, cyproconazole and propiconazole. The structural formula of Azoxystrobin is

[025] Mancozeb ([[l,2-ethanediylbis[carbamodithioato]](2-)]manganese mixture with [[l,2-ethanediylbis[carbamodithioato]](2-)]zinc) belongs to the dithiocarbamate grouping of fungicides and more specifically to the class of compounds known as ethylene bisdithiocarbamates (EBDCs). Mancozeb itself is not fungicidal and can effectively be considered a profungicide which, when exposed to water, breaks down to release ethylene bisisothiocyanate sulfide (EBIS), which is then converted via the action of UV light into ethylene bisisothiocyanate (EBI). Both EBIS and EBI are believed to be the active toxicants and are thought to interfere with enzymes containing sulphydryl groups. This fatal disruption of core enzymatic processes is postulated to inhibit or interfere with at least six different biochemical processes within the fungal cell cytoplasm and mitochondria. [026] The direct effect of mancozeb upon core biochemical processes within the fungus results in inhibition of spore germination. Mancozeb displays the characteristics of a typical multi-site protectant-only fungicide, in that following application onto the target plant, the compound remains on the leaf surface and does not penetrate through the cuticle to where systemic redistribution can occur. The structural formula of mancozeb is

[027] Compositions comprising a single fungicidally active component suffer from numerous drawbacks such as development of resistant fungal species, requirement of high amount and concentration of the active ingredient, environmental damage, seepage of the active component into ground water, phytotoxicity and harmful effects on the health of animals and humans. [028] One embodiment of the present invention provides a novel fungicidal composition comprising: a pyridine carboxamide fungicide; a strobilurin fungicide; a dithiocarbamate fungicide in effective amounts, along with suitable adjuvants.

[029] According to the present embodiment, the pyridine carboxamide fungicide is boscalid, strobilurin fungicide is selected from azoxystrobin, picoxystrobin, pyraclostrobin, trifloxystrobin and dithiocarbamate fungicide is selected from mancozeb, propineb, maneb, metiram, thiram, and ziram. [030] Another embodiment of the present invention provides a novel fungicidal composition comprising:

Boscalid,

Azoxystrobin,

Mancozeb, in effective amounts and - suitable adjuvants.

[031] In an embodiment of the present invention, the novel fungicidal composition comprises of

- Boscalid in a range from 10% to 20% w/w; - Azoxystrobin in a range from 12% to 20% w/w;

- Mancozeb in a range from 45% to 49% w/w; and

- suitable adjuvants.

[032] The novel fungicidal composition of the present invention may be formulated as Capsule suspension (CS), Dispersible concentrate (DC), Dustable powder (DP), Powder for dry seed treatment (DS), Emulsifiable concentrate (EC), Emulsifiable granule (EG), Emulsion water-in-oil (EO), Emulsifiable powder (EP), Emulsion for seed treatment (ES), Emulsion oil-in-water (EW), Flowable concentrate for seed treatment (FS), Granules (GR), Micro-emulsion (ME), Oil- dispersion (OD), Oil miscible flowable concentrate (OF), Oil miscible liquid (OL), Oil dispersible powder (OP), Suspension concentrate (SC), Suspension concentrate for direct application (SD), Suspo-emulsion (SE), Water soluble granule (SG), Soluble concentrate (SL), Spreading oil (SO), Water soluble powder (SP), Water soluble tablet (ST), Ultra-low volume (ULV) suspension, Tablet (TB), Ultra-low volume (ULV) liquid, Water dispersible granules (WG), Wettable powder (WP), Water dispersible powder for slurry seed treatment (WS), Water dispersible tablet (WT), a mixed formulation of CS and SC (ZC), a mixed formulation of CS and SE (ZE), a mixed formulation of CS and EW (ZW). Preferably, the composition of the present invention is formulated as wettable powder (WP). [033] The active compounds within the composition according to the invention have potent microbicide activity and can be employed for controlling undesired micro-organisms, such as fungi, in crop protection or in the protection of materials.

[034] Suitable adjuvants may be a solid or liquid and are generally a substance commonly used in formulation processing process, for example, natural or regenerated minerals, solvents, dispersing agents, wetting agents, adhesives, thickeners, binders or fertilizers.

[035] The compositions preferably contain a wetting agent, dispersing agent, adjuvant and filler. During application, a common adjuvant can be mixed with the composition. [036] Wetting is the first stage of dispersion, in which air surrounding the granular composition is substituted with water. Wetting of the 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 composition to facilitate the process of dispersion of the granules in the liquid. The wetting agent is selected from the group comprising of naphthalene alkyl aryl sulphonate, dioctyl sulfosuccinate, sodium lauryl sulfate, non-ionic ethoxylated polyarylphenol phosphate ester, sodium alkyl naphthalene sulfonate or a combination thereof. Preferably, the wetting agent suitable for use in the present invention are dialkyl naphthalene sulphonate sodium salt, alkylnaphthalene sulfonate (ANS) condensate blend, linear alcohol derivative and polyethylene glycol nonyl phenyl ether ammonium sulfate. Wetting agent is present in a range from 1% to 3% w/w.

[037] It is generally observed that solid particles in a liquid undergo spontaneous aggregation to form lumps. Hence it is recommended to add a dispersing agent which prevents agglomeration of solid particles and keep them suspended in fluid. Accordingly, the composition of the present invention contains dispersing agents such as amine salt of phosphate tristyryl phenol ethoxylated, acrylic copolymer, naphthalene sulphonate of formaldehyde condensate, lignin based sulphonate. One or more dispersing agents may be used in the synergistic composition of the present invention. The dispersing agent suitable for use in the present invention are Sodium salt of methyl naphthalene sulfonate, sodium ligno sulphonate, acrylate copolymer, phenol sulfonic acid-formaldehyde-polycondensation as sodium salt, sodium polycarboxylate, sodium methyl oleoyl taurate and sodium lauryl sulphate or combination thereof. Dispersing agent is present in arange from 1% to 9% w/w.

[038] Adjuvants play an essential role in increasing the biological efficacy of agrochemicals. The role of adjuvants in fungicide formulations is relatively easy to understand since fungicides must always penetrate the targeted organism to have an effect. Physiochemical factors (such as spray adhesion, spray retention, wetting and spreading) and systemic factors (such as uptake of the active ingredient) determine the efficacy of a fungicide. Suitable adjuvants for the purpose of the present invention are amino acids (preferable L-glutamate), trisiloxane ethoxylate polyoxyethylene sorbitol ester, polyalkyleneoxide modified heptamethyl trisiloxane, and micro fibrillated cellulose. Adjuvant is present in a range from 3% to 11% w/w.

[039] With fungicides, the situation is more complicated. The fungicide can be active against the fungal spores on the leafs surface, as well as active inside the leafs cells. Using an adjuvant introduces another factor in the interaction between the fungus, fungicide, and host plant. The selection of an adjuvant can enhance the uptake and transport of the fungicide spray solution into the cell wall of the fungus. It is this fungicide-adjuvant interaction that makes selection of an adjuvant specific for a particular fungicide and fungus disease. The adjuvants balance the two driving factors of formulation stability and fungicide efficacy. Adjuvant suitable for use in the present invention is amino acids.

[040] As used herein, the term “filler” refers to solid chemicals that are added to a fungicide formulation to aid in the delivery of the active ingredient.

[041] Filler is selected from the group comprising of, but not limited to, natural minerals such as corn starch, lactose monohydrate, quartz, talc, kaolin, pyrophyllite, montmorillonite, attapulgite, bentonite clay, china clay, kieselguhr, chalk, zeolite, calcite, sericite, acid clay, diatomaceous earth, natural rock, Fuller’s earth, meerschaum, gibbsite, dolomite or pumice; synthetic minerals such as precipitated silica, fumed silica, sodium silicate, alumina, aluminium silicate, aluminium hydroxide; inorganic salts such as calcium carbonate, ammonium sulfate or other ammonium salts, sodium sulfate, potassium chloride. The filler may be used alone or in combination thereof. Preferably, the filler suitable for use in the present invention are aluminium silicate, com starch, lactose monohydrate, and calcium carbonate. Filler is present in a range from 12% to 19% w/w. [042] A method for applying the composition of the present invention includes applying the composition of the present invention on the seed, bulbs, roots of transplants, and other propagative organs and aboveground part of plants, especially the leaves or foliage. The frequency of application and application amount depend on the biological characteristics and the climate survival conditions of the fungal pathogen. A liquid formulation containing the composition may be used to wet the plant growing place such as rice field, or the composition may be applied in the soil in the solid form, such as in the granular form (soil application), so that the composition can get into the plant body (systemic action) through the plant roots from the soil.

[043] These compositions may merely contain the active components in effective amount and be applied, and may also be mixed with additives for use, so the composition of the present invention may be formulated into various formulations, for example, wettable powder. According to the properties of these compositions and the purpose to be achieved by applying the composition as well as the environmental conditions, the method for applying the composition may be selected to be spraying, atomizing, dusting, scattering or pouring and the like.

[044] It has been surprisingly found that the novel fungicidal composition of the present invention delays the appearance of the resistant strains of fungi and achieves effective and economical control of undesired fungicide infection. The composition achieves improved biological activity by enhancing overall control of diseases caused by fungi over a shorter period of time. Additional benefits of using the fungicidal composition of the present invention includes reduced risk of occupational hazard, lower cost of application, better cost: benefit ratio to the end user, reduced fuel and labour cost, saving in applicator’s time and loss caused by mechanical damage to the crop and soil. [045] The present invention is further illustrated by the following examples which are provided merely to be exemplary of the inventions and is not intended to limit the scope of the invention. Certain modifications and equivalents will be apparent to those skilled in the art and are intended to be included within the scope of the present invention. Examples:

[046] Example 1: Preparation of composition of Boscalid, Azoxystrobin and Mancozeb in wettable powder form

The composition of Boscalid, Azoxystrobin and Mancozeb in wettable powder form is prepared by following steps as below: Step 1.0: weighing the raw materials like actives Boscalid, Azoxystrobin and Mancozeb and adjuvants according to the batch size. For the purpose of illustration, the raw materials are as follows

Aluminium silicate L-glutamate

Sodium ligno Sulphonate

Dialkyl naphthalene sulphonate sodium salt

Sodium salt of methyl naphthalene sulfonate

Boscalid Azoxystrobin

Mancozeb

Step 2.0: Pre-mixing the sample for 1 hour in a pre-blender.

Step 3.0: Milling the sample through air jet machine at inlet pressure 2-3 kg/cm2, grinding pressure 6 -6.5 kg/cm2 to get desired particle size, Step 4.0: Collecting the milled material, and checking for the particle size < 15 micron,

Step 5.0: Post blending the sample for Ihr in a post blender.

Step 6.0: Sending the sample for all physico-chemical analysis.

Step 7.0: Pack the formulated material in a suitable packet.

[047] Example 2: Compositions of the present invention

The illustrative embodiments show the composition of Boscalid, Azoxystrobin and Mancozeb in wettable powder form in different amount as follows: Table 1: Boscalid 10% + Azoxystrobin 12% + Mancozeb 45% WP

Table 2: Boscalid 12% + Azoxystrobin 14% + Mancozeb 47% WP

Table-3: Boscalid 14% + Azoxystrobin 16% + Mancozeb 49% WP

Table-4: Boscalid 16% + Azoxystrobin 18% + Mancozeb 46.5% WP

Table-5: Boscalid 20% + Azoxystrobin 20% + Mancozeb 47% WP

[048] Example 3: Efficacy study for combination of Boscalid 10% + Azoxystrobin 12% + Mancozeb 45% WP in Grape downy mildew

Field Bio-efficacy trials: Grape downy mildew.

Trial 1: Bio-efficacy against grapes downy mildew

[049] The Downy mildew is caused by the Oomycete group of fungal pathogens Plasmopara viticola. This is potentially devasting disease that can infect grapes foliage and berries at any stage of crop development. The pathogen overwinters as thick-walled spores (oospores) in leaf debris from the previous growing season on

10 the soil surface under vines. Oospores at or near the soil surface will germinate in spring by producing sporangia that are rain-splashed or wind-blown to susceptible grape tissues. Sporangia release swimming zoospores in a film of water (rain or dew) which infect the leaves by penetrating the leaf stomata within several hours. Light green or yellow lesions, called “oil spots,” on leaves appear within 5 to 17 days after

15 infection, depending on the temperature.

[050] Disease development required cool, moist weather under the favourable condition foliar symptoms appear as yellow circular spot with an oily appearance (oily spots). Young oily spots on young leaves surrounded by a brownish yellow halo. The halo fades as the oil spots matures. Under favourable weather conditions, large numbers

20 of oil spots may develop and coalesce to cover most of leaf surface. [051] The field trial was conducted to evaluate the efficacy of innovative mixtures of Azoxystrobin, Boscalid and Mancozeb against grapes downy mildew. Trial was conducted with randomized block design with net plot size of 5m x 10m. Grape crop was raised with all standard agronomic practices. Spraying was done with manual

5 operated backpack knapsack sprayer with 1000 L of water spray volume per hectare at 8 to 10 days after pruning.

[052] The visual observations were recorded for % disease control from ten plants per plot. The observations were recorded at before spraying, 5 DAA (Days after application) and 10 DAA (Days after application).

10 Table 6: Downy mildew disease control in grapes:

WP — Wettable powder and DAA - Days after application.

[053] The trial results in table 6 show excellent efficacy of Boscalid 10% + Azoxystrobin 12% + Mancozeb 45% WP combinations against downy mildew 15 disease of grape. The solo application of three active ingredients tested here, were also not able to provide satisfactory control of downy mildew disease. The combination of Boscalid 10% + Azoxystrobin 12% + Mancozeb 45% WP is found very promising against grapes downy mildew in terms of efficacy as well as residual control.

20

[054] SYNERGY STUDIES: [055] After calculating % disease control, the synergism was calculated by below formula:

[056] The synergistic pesticidal action of the inventive mixtures calculated by Colby’s formula as follows:

[057] Appropriate analysis of plant response to pesticide combination is critical in determining the type of activity observed. The most widely used model is one Gowing* derived and Colby** modified. Gowing described a mathematical formula for calculating the predicting response values for pesticide mixtures. He suggested the expected (E) percent inhibition of growth induced by pesticide A plus pesticide B and plus pesticide C is as follows, *(Jerry Flint et al, 1988)*** If Al = the percent inhibition of growth by pesticide A at given rate B 1 = the percent inhibition of growth by pesticide B at given rate then, ABC

Expected ( -

10000

Where,

A = observed efficacy of active ingredient A at the same concentration as used in the mixture.

B = observed efficacy of active ingredient B at the same concentration as used in the mixture.

C = observed efficacy of active ingredient C at the same concentration as used in the mixture.

[058] When the percentage of pesticidal control observed for the combination is greater than the expected percentage, there is a synergistic effect. (Ratio of O/E > 1, means synergism observed.)

Reference:

*Gowing, D. P. 1960. Comments on tests of herbicide mixtures. Weeds 8:379—391. **Colby, S. R. 1967. Calculating synergistic and antagonistic responses of herbicide combinations. Weeds 15:20-22

Table 7: Percent downy mildew disease control at 10 DAA

[059] The results in table 7 clearly demonstrates synergy between Boscalid, Azoxystrobin and Mancozeb in controlling grapes downy mildew disease. The large difference between the observed and the expected efficacy clearly demonstrates the synergistic effect of the combination.

[060] Example 4: Efficacy study for combination of Boscalid 10% + Azoxystrobin 12% + Mancozeb 45% WP in Tomato Early and Late blight. Field Bio-efficacy trials: Tomato Early and Late blight.

Trial 1: Bio-efficacy against Tomato Early blight -

[061] The early blight is caused by the fungal pathogen Alternaria solani. This is potentially devasting disease. Warm, humid (24-29°C/ 75-84°F) environmental conditions are conducive to infection. Its major threat to many vegetable and fruit crops and can also affect the crop stand and yield. The first symptoms of early blight appear as small, circular, or irregular, dark brown to black spots on the older (lower) leaves. These spots enlarge up to 3/8 inch in diameter and gradually may become angular- shaped. These first lesions appear about two to three days after infection, with further sporulation on the surface of these lesions occurring three to five days later. Early blight lesions can be diagnosed in the field easily due to the dark concentric rings alternating with bands of light-tan tissue, giving them a distinctive target spot appearance. Multiple lesions on the same leaf also may coalesce, or grow together, to form one mass. As lesions coalesce, chlorosis (yellowing of plant tissue) may be visible due to clusters of infection. Elongated, brown to black lesions also may develop on stems and petioles of infected plants.

[062] The field trial was conducted to evaluate the efficacy of innovative mixtures of Boscalid, Azoxystrobin and Mancozeb against Alternaria solani fungus in

Tomato crop. Trial was conducted with randomized block design with net plot size of 5m x 6m. Tomato crop was raised with all standard agronomic practices.

Spraying was done with manual operated backpack knapsack sprayer with 500 L of water spray volume per hectare at 45 days after planting. [063] The visual observations were recorded for % disease control from ten plants per plot. The observations were recorded at before spraying, 7 DAA (Days after application) and 14 DAA (Days after application).

Table 8: Early blight disease control in Tomato:

WP — Wettable powder and DAA - Days after application. [064] The trial results in table 8 show excellent efficacy of Boscalid 10% + Azoxystrobin 12% + Mancozeb 45% WP combinations against Early blight disease of Tomato. The solo application of three active ingredients tested here, were also not able to provide satisfactory control of Early blight disease. The combination of

5 Boscalid 10% + Azoxystrobin 12% + Mancozeb 45% WP found very promising against Tomato Early blight in terms of efficacy as well as residual control.

Table 9: Percent Early blight disease control at 14 DAA

1 065] The results in table 9 clearly demonstrates synergy between Boscalid, Azoxystrobin and Mancozeb in controlling Tomato Early blight disease. The large difference between the observed and the expected efficacy clearly demonstrates the synergistic effect of the combination.

15[066] Trial 2: Bio-efficacy against Tomato Late blight

[067] The late blight is caused by the Oomycete group of fungal pathogen Phytophthora infestans. This is potentially devasting disease can infect tomato foliage and fruit at any stage of crop development. The first symptoms of late blight in the field are small, light to dark green, circular to irregular- shaped water-soaked 20 spots. These lesions usually appear first on the lower leaves. Lesions often begin to develop near the leaf tips or edges, where dew is retained the longest. During cool, moist weather, these lesions expand rapidly into large, dark brown or black lesions, often appearing greasy. The lesions are not limited by leaf veins, and as new infections occur and existing infections coalesce, entire leaves can become blighted and killed within just a few days. The lesions also may be present on petioles and stems of the plant. Maximum and minimum temperatures in the range of 16-20°C and 1-6°C were found favourable for Tomato blight disease. Similarly, relative humidity, rainfall, and wind speed in the range of 63-71%, 1.5-3.75 mm and 1-5.5 Km/h, respectively, were conducive for PLB disease which are helpful in disease development. [068] The field trial was conducted to evaluate the efficacy of innovative mixtures of Boscalid, Azoxystrobin and Mancozeb against Phytophthora infestans fungus in tomato crop. Trial was conducted with randomized block design with net plot size of 5m x 6m. Tomato crop was raised with all standard agronomic practices. Spraying was done with manual operated backpack knapsack sprayer with 500 L of water spray volume per hectare at 45 days after planting.

[069] The visual observations were recorded for % disease control from ten plants per plot. The observations were recorded at before spraying, 7 DAA (Days after application) and 14 DAA (Days after application). Table 10: Late blight disease control in Tomato:

WP - Wettable Powder and DAA - Days after application. [070] The trial results in table 10 show excellent efficacy of Boscalid 10% + Azoxystrobin 12% + Mancozeb 45% WP combinations against late blight disease of Tomato. The solo application of two active ingredients tested here, were also not able to provide satisfactory control of late blight disease. The combination of Boscalid 10% + Azoxystrobin 12% + Mancozeb 45% WP found very promising against Tomato late blight in terms of efficacy as well as residual control.

Table 11: Percent late blight disease control at 14 DAA:

[071] The results in table 11 clearly demonstrates synergy between Boscalid, Azoxystrobin and Mancozeb in controlling late blight disease in Tomato. The large difference between the observed and the expected efficacy clearly demonstrates the synergistic effect of the combination.

[072] Although the present invention has been described and illustrated with respect to preferred embodiments and a preferred user thereof, it is not to be so limited since modifications and changes can be made therein which are within the full scope of the invention.

Claims

We Claim:

1. A fungicidal composition comprising: a pyridine carboxamide fungicide; a strobilurin fungicide; a dithiocarbamate fungicide in effective amounts, and adjuvants.

2. The fungicidal composition as claimed in claiml comprising

Boscalid, a pyridine carboxamide;

Azoxystrobin, a strobilurin;

Mancozeb, a dithiocarbamate and adjuvants.

3. The fungicidal composition as claimed in claim 2, wherein Boscalid is in a range from 10% to 20% w/w, Azoxystrobin is in a range from 12% to 20% w/w and Mancozeb is in a range from 45% to 49% w/w.

4. The fungicidal composition as claimed in claim 2, wherein adjuvants are selected from the group comprising wetting agent, dispersing agent, adjuvant and filler.

5. The fungicidal composition as claimed in claim 4, wherein the wetting agent is selected from the group comprising naphthalene alkyl aryl sulphonate, dioctyl sulfosuccinate, sodium lauryl sulfate, non-ionic ethoxylated polyarylphenol phosphate ester, sodium alkyl naphthalene sulfonate, dialkyl naphthalene sulphonate sodium salt, alkylnaphthalene sulfonate (ANS) condensate blend, linear alcohol derivative and polyethylene glycol nonyl phenyl ether ammonium sulfate or a combination thereof, present in an amount of 1 to 3% (w/w).

6. The fungicidal composition as claimed in claim 4, wherein the dispersing agent is selected from the group comprising sodium salt of methyl naphthalene sulfonate, sodium ligno sulphonate, acrylate copolymer, phenol sulfonic acid-formaldehyde- polycondensation as sodium salt, sodium polycarboxylate, sodium methyl oleoyl taurate and sodium lauryl sulphate, or a combination thereof present in a range from 1% to 9% w/w.

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7. The fungicidal composition as claimed in claim 4, wherein the adjuvant is selected from the group comprising of amino acids, trisiloxane ethoxylate, polyoxyethylene sorbitol ester, polyalkyleneoxide modified heptamethyl trisiloxane, and micro fibrillated cellulose, present in an amount of 3% to 11% w/w.

8. The fungicidal composition as claimed in claim 4, wherein the filler is selected from the group comprising aluminium silicate, com starch, lactose monohydrate, and calcium carbonate, present in a range from 12% to 19% w/w.

9. The fungicidal composition as claimed in claim 2, wherein the composition is formulated as wettable powder.