AU635747B2 - Pesticidal compositions - Google Patents

Description

PESTICIDAL COMPOSITIONS

The present invention relates to novel compositions, their preparation, formulations containing them and to their use for the control of insect pests.

Insecticides have been increasingly used in agriculture over the past thirty years to control insect pests, thereby increasing the yield per acre that land under cultivation can provide. However, with increasing use of a particular insecticide, the insect population modifies its susceptibility to the insecticide and resistance to that insecticide may occur. Thus, by 1980, resistance to the organochlorine and organophosphorous insecticides was common and, by 1988, resistance to the pyrethroids in certain insect species was becoming widespread. Thus, for example, pyrethroid resistance in heliothis species in Australia, Thailand, Turkey and the Americas is becoming a major problem in the cotton growing industry in these countries.

There are a number of ways of countering increasing resistance of insect species to insecticides. One way is to develop new series of insecticides which have a different mode of action to existing insecticides and are not cross-resistant with these. However, this is time-consuming and expensive and there is no guarantee of success. A further possibility is to increase the activity of existing series of insecticides so that resistant insects become susceptible to the insecticides. This can be done by developing more active analogues of existing insecticides or by increasing the activity of existing insecticides by combining them with a substance which increases their activity (a "potentiator") or formulating them in a manner which enables them to overcome or by-pass the insects' resistance mechanism.

Piperonyl butoxide is a potentiator that has been commonly used to potentiate the activity of the pyrethrins and the pyrethroids against susceptible and resistant insect species. Piperonyl butoxide (5-[2-(2-butoxyethoxy)ethoxymethyl]-6-propyl-l,3-benxodioxole) acts by inhibiting enzymes, mixed function oxidases, which are present in susceptible and more so in pyrethrin/pyrethroid and some carbamate resistant insects and degrades these insecticides.

n-Propyl- allate is an antioxidant that is commonly used in the food industry as a preservative. It has also been used in insecticide formulations, for example, Hungarian Patent Application No 34100 discloses insecticidal compositions containing inter alia permethrin, piperonyl butoxide and an antioxidant such as n-propyl gallate. We have discovered that BHT and BHA can potentiate the activity of insecticides, such as the pyrethrins, the pyrethroids and the organophosphorus series of insecticides, against susceptible and resistant insect species including Musca domestica and heliothis spp. In addition, we have found that the potentiating effect of piperonyl butoxide appears to be adversely effected by light, i.e. piperonyl butoxide is photosensitive; the addition of gallic acid esters to piperonyl butoxide protects piperonyl butoxide against light induced degradation.

Accordingly, in a first aspect, the present invention provides a composition which comprises piperonyl butoxide a gallic acid ester in a ratio of 3:1 to 1:10 by weight. Suitable gallic acid esters include alkyl esters, most suitably those formed from straight chain alkyl esters where the alkyl substituent contains up to 12 carbon atoms, in particular propyl, octyl and dodecyl gallate esters. Preferably the gallic acid ester is n-propyl gallate.

In a further aspect, the present invention provides an insecticidal composition which comprises an insecticide, piperonyl butoxide and n-propyl gallate, wherein piperonyl butoxide and n-propyl gallate are in a ratio of 3:1 to 1:10 by weight, suitably in a ratio of 2.5:1 to 1:7 and are preferably in a ratio of 2:1 to 1:5 by weight. Suitable insecticides include organophosphorous, pyrethroid, pyrethrin and lipid amide pesticides. Suitable organophosphorous insecticides include:-

0,0-diethyl-0-(3-chloro-4-methyl-7-coumarinyl)phosphorothioate (coumaphos) ;

0,0-diethyl-0-(2,5-dichloro-4-bromophenyl) phosphorothiate (bromophos- ethyl) ;

0,0-diethyl-0-(2-isopropyl-6-methyl-pyrimidin-4-yl)phosphorothioate (diazinon) ;

2,3-p-dioxanedithiol S.S-bis. 0,0-diethyl phosphorodithioate (diox- athion) ;

0,0-diethyl-0-(3,5,6-trichloro-2-pyrid l)phosphorothioate (chlorpyrifos) ;

0,0,0' ,0' -tetraethyl, S,S' -methylenediphosphorodithioate (ethion) ; 3-(Dimethoxyphosphinyloxy)-N-dimethyl-cis-crotonamide (dicrotophos) ; S-(1,2-dicarbethoxy ethyl)-0,0-dimethylphosphorodithioate (malathion) ; cis-l-methyl-2-(l-phenylethoxycarbonyl)vinylphosphate (crotoxyphos) ; 0-ethyl-0-(quinol-8-yl)phenylphosphorothioate (oxinothiophos) ; (S-(5,7-dichlorobenzoxazol-2-yl-methyl}-0,0-diethyl phosphorodithio¬ ate) (benoxanphos) ;

S-f{4-chlorophenyl)-thio]-methyl)-0,0-diethyl phosphorodithioate (carbo phenothion) ;

S-{l,3-dihydro-l,3-dioxo-2H-isoindol-2-yl)-methyl)-0,0-dimethyl phosphorodithioate (phosmet) ;

2-Chloro-l-(2,4-dichlorophenyl)vinyldiethylphosphate (chlorofenvin- phos) ;

0,0-diethyl -cyanobenzylideneamino-oxyphosphonothioate (phoxim) ; 0,0-dimethyl cis-1-methyl-2-methylcarbamoylvinyl-phosphate (monocroto- phos) ;

(E)-0-2-isopropoxycarbonyl-l-meth lvinyl 0-methyl ethylphosphoramid- othioate (propetampho) ;

0-2-diethylamino-6-methylpyrimidin-4-yl 0,0-dimethyl phosphorothioate (pirimiphos methyl) ;

0-2-diethylamino-6-meth lpyrimidin-4-yl 0,0-diethyl phosphorothioate (pirimiphos ethyl) 0-4-dimethylsulphamoylphenyl-O,0-dimethylphosphorothioate (famphur) . Suitable pyrethroid insecticides include those of the formula (I)

where

or

and n is 0 or 1,

1 2 1

R is halo, CF„ or CHF^O, R is hydrogen or halo, and Z and Z are each independently selected from halo, CF_ and methyl, X is halo, and

X¹ is H, CN or OCH

Preferred pyrethroids for inclusion within the present invention include: -

3-phenoxybenzyl-(IRS)-cis.trans-3-(2,2-dichlorovinyl-2,2-dimethyl- cyclopropane-1-carboxylate (permethrin) ,

(RS)-α-cyano-3-phenoxybenzyl-(IRS)-cis.trans-3-(2,2-dichlorovinyl)- 2,2-dimethylcyclopropane-l-carboxylate (cypermethrin) and its indivi¬ dual isomers such as the (IRS) cis isomer (alphamethrin) (S)-α-cyano-3-phenoxybenzyl-(IR)-cjLs.-3-(2,2-dibromovinyl)-2,2-dimethyl cyclopropane- 1-carboxylate (deltamethrin)

(RS)-α-cyano-3-phenoxybenzyl-(Z)-(IRS)-cjLs-3-(2-chloro-3,3,3-trifluoro propenyl)-2,2-dimethylcyclopropanecarboxylate (cyhalothrin) and a mixture of its (S)(Z)-(IR)-cis and (R)(Z)-(IS)-cis-isomers. (RS)-α-cyano-3-phenoxybenzyl (RS)-2-(4-chlorophenyl)-3-methylbutyrate (fenvalerate) and the single (S) , (S) isomer (esfenvalerate) (RS)-α-cyano-3-phenoxybenzyl (S)-2-(4-difluoromethoxyphenyl)-3-methyl butyrate (flucythinate)

(RS) -a -cyano-3-phenoxybenzyl N(2-chloro- ,α, -trifluoro-p-tolyl)-D- valinate (fluvalinate)

(RS) -a-cyano-4-fluoro-3-phenoxybenzyl(IRS)-cis-trans-3-(2,2-dichloro- vinyl) -2,2-dimethylcyclopropanecarboxy late (cyfluthrin) (RS)-α-cyano-4-fluoro-3-phenoxybenzyl(IRS)-cis-trans-3-(2-chloro-2(4- chlorophenyl)vinyl)-2,2-dimethylcyclopropanecarboxylate (flumethrin) 2-methylbiphenyl-3-ylmethyl(Z)-(IRS,3RS)-3-(2-chloro-3,3,3-trifluoro- prop-1- -enyl)2,2-dimethyl cyclopropoane carboxylate (Bifenthrin) .

Suitable lipid amide pesticides include those described in European Patent Application nos. Ill 105, 164 187, 194764, 209 289, 225 011, 251472, 269457 and 317 188.

The precise amount of insecticide to be applied will depend on the Inherent activity of the insecticide against the insect species to be controlled, the method of application and the nature of the formulation to be applied and whether or not piperonyl butoxide is included In the formulation but in general the following quantities will be applied.

Pyrethroids between 5 and 150 g/hectare

(i.e. 0.0125 and 0.4 lbs/acre) Natural pyrethrin between 2 and 12 ozs/acre

Organophophorous insecticides between 50 and 100 g/hectare (0.125 and 2.5 lbs/acre)

Lipid amides between 5 and 150 g hectare (0.0125 and 0.4 libs/acre) .

Piperonyl butoxide between 100 and 1200 g/hectare (0.25 and 3.0 lbs/acre) . n-Propyl gallate between 33 and 6000 g/hectare (0.08 - 15 lbs/acre) .

The formulation for agrochemical use which comprises n-propyl gallate and piperonyl butoxide and/or one or more insecticides from the organophosphorous, pyrethroid, pyrethrin or lipid amide classes of insecticides may contain a suitable carrier. The carrier may be liquid, solid or gaseous or comprise a mixture of such substances, and the composition of the present invention may be present in a concentration of from 0.025 to 99% w/v depending upon whether the formulation requires further dilution.

Dusts, powders and granules and other solid formulations comprise the compositions of the present invention in intimate admixture with a powdered solid inert carrier for example suitable clays, kaolin, bentonite, attapulgite, absorbent carbon black, talc, mica, chalk, gypsum, tricalcium phosphate, powdered cork, magnesium siliate, vegetable carriers, starch and diatomaceous earths. Such solid formulations are generally prepared by impregnating the solid diluents with solutions of the combinations of the present invention in volatile solvents, evaporating the solvents and, if desired grinding the products so as to obtain powders and, if desired, granulating, compacting or encapsulating the products.

Sprays of the compositions of the present invention may comprise a solution in an organic solvent (e.g. those listed below) or an emulsion in water (dip wash or spray wash) prepared in the field from an emulsifiable concentrate (otherwise known as a water miscible oil) which may also be used for dipping purposes. The concentrate preferably comprises a mixture of the active ingredients, with or without an organic solvent and one or more emulsifiers. Solvents may be present within wide limits but preferably in an amount of from 0 to 90% w/v of the composition and may be selected from kerosene, ketones, alcohols, xylene, aromatic naphtha, and other solvents known in the formulating art. The concentration of emulsifiers may be varied within wide limits but is preferably in the range of 5 to 25% w/v and the emulsifiers are conveniently non-ionic surface active agents including polyoxyalkylene esters of alkyl phenols and polyoxyethylene derivatives of hexitol anhydrides and anionic surface active agents including Na lauryl sulphate, fatty alcohol ether sulphates, Na and Ca salts of alkyl aryl sulphonates and alkyl sulphosuccinates, soaps, leuthrins, hydrolysed glues, etc. Cationic emulsifiers include benzalkonium chloride and quaternary ammonium ethosulphates. Amphoteric emulsifiers include carboxymethylated oleic imidazoline and alkyl dimethyl betain.

Wettable powders comprise an inert solid carrier(s) , one or more surface active agents, and optionally stabilisers and/or anti-oxidants.

Emulsifiable concentrates comprise emulsifying agents, and often an organic solvent, such as kerosene, ketones, alcohols, xylenes, aromatic naphtha, and other solvents known in the art.

Wettable powders and emulsifiable concentrates will normally contain from 5 to 95% by weight of the active ingredient, and are diluted, for example with water, before use.

Aqueous suspensions of a compound of Formula (I) may comprise a suspension in water together with suspending, stabilising or other agents. The suspensions or solution may be applied per se or in a diluted form in known fashion.

Aerosol sprays may be prepared as a simple solution or suspension of the active ingredient in the aerosol propellant and co-solvent such as halogenated alkanes and the solvents referred to above, respectively. Pour-on formulations may be made as a solution or suspension of a combination of the present invention in a liquid medium. Suitably-moulded, shaped plastics articles impregnated with a combination of the present invention including impregnated collars, tags, bands, sheets and strips are also useful formulations. Suitably the plastics material is a polyvinyl chloride (PVC) .

The composition of the present invention may be used to control insect and acarine pests.

Thus the present invention provides a method for the control of arthropods and which comprises administering to the arthropod or to its environment an arthropodically effective amount of an insecticidal composition of the present invention. The present invention also provides a method for the control and/or eradication of arthropod infestations of animals and/or of plants, (including trees), and/or stored products which comprises administering to the animal or locus an effective amount of an insecticidal composition of the present invention. The present invention further provides for the insecticidal compositions of the present invention for use in human and veterinary medicine, in public health control and in agriculture for the control of arthropod and/or helminth pests.

The insecticidal compositions of the present invention are of particular value in the protection of field, forage, plantation, glasshouse, orchard and vineyard crops, of ornamentals and of plantation and forest trees, for example, cereals (such as maize, wheat, rice, sorghum), cotton, tobacco, vegetables and salads (such as beans, cole crops, curcurbits, lettuce, onions, tomatoes and peppers), field crops (such as potato, sugar beet, ground nuts, soyabean, oil seed rape), sugar cane, grassland and forage (such as maize, sorghum, lucerne), plantations (such as of tea, coffee, cocoa, banana, oil palm, coconut, rubber, spices), orchards and groves (such as of stone and pip fruit, citrus, kiwifruit, avocado, mango, olives and walnuts), vineyards, ornamental plants, flowers and shrubs under glass and in gardens and parks, forest trees (both deciduous and evergreen) in forests, plantations and nurseries.

They are also valuable in the protection of timber (standing, felled, converted, stored or structural) from attack by sawflies (e.g. Urocerus) or beetles (e.g. scolytids, platypodids, lyctids, bostrychids, cerambycids, anobiids) .

They have applications in the protection of stored products such as grains, fruits, nuts, spices and tobacco, whether whole, milled or compounded into products, from moth, beetle and mite attack. Also protected are stored animal products such as skins, hair, wool and feathers in natural or converted form (e.g. as carpets or textiles) from moth and beetle attack; also stored meat and fish from beetle, mite and fly attack.

The insecticidal compositions of the present invention are thus useful in the control of arthropods e.g. insects and acarines in any environment where these constitute pests, e.g. in agriculture, in animal husbandry, in public health control and in domestic situations.

Insect pests include members of the orders Coleoptera (e.g. Anobium. Geutorhynchus. Rhynchophorus. Cosmopolites. Lissorhoptrus. Meligethes. Hvpothenemus. Hylesinus. Acalvmma. Lema. Psylliodes. Leptinotarsa. Gonocephalum. Agriotes., Dermolepida. Heteronvchus. Phaedon. Triboliuπt. Sitophilus. Diabrotica. Anthonomus or Anthrenus spp.), Lepidoptera (e.g. Ephestia. Mamestra, Earias. Pectinophora. Ostrinia, Trichoplusia. Pieris. Laphvpm . Agrotis. Amathes. Wiseana. Tryporysa. Diatraea. Sporganothis. Cvdia. Archips. Plutella. Chilo. Heliothis. Spodoptera or Tineola spp.), Diptera (e.g. Musca. Aedes. Anopheles. Cule . Glossina. Simuliu . Sto oxys. Haematobia. Tabanus. Hydrotaea. Lucilia. Chrvsomia. Callitroga. Dermatobia. Gasterophilus. Hypoderma. Hylemvia. Atherigona. Chlorops. Phvtomvza. Ceratitis. Liriomvza and Melophagus spp.), Phthiraptera (Malophaga e.g. Damalina spp. and Anoplura e.g. Lino n thus and Haematoninus spp.), Hemiptera (e.g. Aphis. Bemisia, Phorodon. Aeneola ia. Empoasca. Parkinsiella. Pyrilla. Aonidiella. Coccus, Pseudococus. Helopeltis. Lveus. Dysdercus. Oxycarenus. Nezara. Aleurodes. Triatoma. Psylla. Mysus. M oura. Phylloxera. Adelves. Niloparvata. Nephrotetix or Cimex spp.), Orthoptera (e.g. Locusta. Gryllus. Schistocerca or Acheta spp.), Dictyoptera (e.g. Blattella. Periplaneta or Blatta spp.), Hymenoptera (e.g. Athalia. Cephus. Atta. Solenopsis or Monomorium spp.), Isoptera (e.g. Odontoter es and Re iculitermes spp.), Siphonaptera (e.g. Ctencephalides or Pulex spp.), Thysanura (e.g. Lepisma spp.), Dermaptera (e.g. Forficula spp.), Pscoptera (e.g. Peripsocus spp.) and Thysanoptera (e.g. Thrips tabaci) .. Acarine pests include ticks, e.g. members of the genera Boophilus. Ornithodorus. Rhipicephalus. Amblyomma. Hvalomma. Ixodes. Haemaphvsalis. Dermacentor and Anocentor. and mites and manges such as Ac rus. Tetranychus. Psoroptes. Notoednes. Sarcoptes. Psorergates. Chorioptes. Eutro bicula. Demodex. Panonychus. Brvobia. Eriophves. Blaniulus. Polyphagotarsonemus. Scutigerella. and Oniscus spp.

The following Examples are provided by way of illustration of the present invention and should not be construed as constituting a limitation thereof in any way.

Example 1

General Purpose compositions for insecticidal formulations

% w/w

Piperonyl butoxide 68.3 60.7 n-propyl gallate 22.7 30.3 Emulsifiers 9.0 9.0

ratio piperonyl butoxide: 3:1 2:1 n-propyl gallate

Example 2

General Purpose compositions for insecticidal formulations

% w/w

Piperonyl butoxide 56.25 50 10 n-propyl gallate 18.75 25 50

Emulsifiers 9 9 9

Solvesso-200 8 8 15.5 propan-2-ol 8 8 l-methyl-2-pyrrolidone 15.5

ratio piperonyl butoxide: 3:1 2:1 1:5 n-propyl gallate Example 3

General Purpose composition for insecticidal formulations

% w/w

Piperonyl butoxide 56.25 50.0 12.5 n-propyl gallate 18.75 25.0 62.5 ρropan-2-ol 6.5 6.5 6.5 Solvesso-200 6.5 6.5 6.5 Emulsifiers 12.0 12.0 12.0

ratio piperonyl butoxide: 3:1 2:1 1:5 n-propyl gallate

Example 4

Half life data showing increased stability of compositions

The half life of compositions were measured using standard methods.

The compositions were applied as a thin film onto glass plates at a

2 2 rraattee ooff 5500mmgg ppiippeerroonnyyll bbuuttooxxiiddee ppeerr mm aanncd maintained under lighting conditions equivalent to tropical sunlight.

Composition Ratio of piperonyl T 1/2 butoxide : n-propyl (Half life in gallate minutes)

Piperonyl butoxide alone - 30

Piperonyl butoxide and 9:1 70 n-propyl gallate 3:1 117

2:1 173

1:5 260 Example 5

Field Trial Data

Heliothis on cotton

Cotton plants were sprayed according to the three treatments below. Insects (Heliothis arπάgra) were caged onto the foliage at intervals up to 6 days after spraying and the % control results were as follows:

Trial 1

Treatment % Control of H.armigra

Days after spraying 0.25 2 days 5 days

1) Alphacypermethrin 43 33 30

(40g/ha)

2) Alphacypermethrin 93 83 37

(40g/ha) + technical piperonyl butoxide (200g/ha)

3) Alphacypermethrin

+ propyl gallate stabilised piperonyl butoxide * 100 100 50

(200g/ha)

* ratio propyl gallate: piperonyl butoxide 1:2 Trial 2

1) Alphacypermethrin 80 26.6 20 13.3 6.6

(40g/ha)

2) Alphacypermethrin 100 60 40 26.6 3.0

(40g/ha) + piperonyl butoxide stabilised with BHT (200g/ha)

3) Alphacypermethrin 100 66.6 46.6 30 6.6

(40g/ha) + piperonyl butoxide stabilised with propyl gallate (200g/ha)

Colorado Beetle on Potatoes

Potato plants were treated as indicated and the number of insects present per ive plants recorded at intervals as follows:

No. of insects/5 plants

Treatment lb active Date: 29 Jun 5th Jul 10th Jul Season ingredient/ Average acre

Untreated - 44.5 157.8 133.0 111.8

Permethrin 0.006 26.5 98.3 124.0 82.9

(PRM) PRM + 0.006 + 0.25 17.3 60.5 68.8 48.9 piperonyl butoxide (PB)

PRM + PB 0.006 + 0.25 15.3 36.8 64.5 38.9 (propyl gallate stabilised)

PRM 0.012 33.8 87.0 104.8 75.9

PRM + PB 0.006 + 0.50 14.8 38.3 33.8 29.0

PRM + PB + 0.006 + 0.50 10.5 24.5 26.5 20.5 propyl gallate

Claims (1)

1. 1) An insecticidal composition which comprises an organophosphorous, pyrethroid, pyrethrin and/or lipid amide insecticide in combination with piperonyl butoxide and a gallic acid ester in a ratio of 3:1 to 1:10.

   2) A combination of piperonyl butoxide with a gallic ester in a ratio of 3:1 to 1:10.

   3) A combination of piperonyl butoxide with a gallic acid ester in a ratio of 1:5.

   4) A composition for agrochemical use which comprises piperonyl butoxide, a gallic acid ester and/or one or more insecticides from the organophosphorous, pyrethroid, pyrethrin or lipid amide classes of insecticide and an agrochemically acceptable carrier.

   5) A composition or combination according to claims 1, 2, 3 or 4 wherein the gallic acid ester is n-propyl gallate.

   6) A method for the control of arthropods which comprises administering to the arthropod or to its environment an arthropodically effective amount of a composition according to any of the preceding claims.

   7) A method for the control and/or eradication of arthropod infestations of animals and/or of plants and/or stored products which comprises administering to the animal or locus an effective amount of a composition according to any of the preceding claims.

   8) A method for the control and/or eradication of heliothis on cotton which comprises administering to the cotton plant an effective amount of a composition according to any of the preceding claims. 9) A method for the control of beetles on potato which comprises administering to the potato plant an effective amount of a composition according to any of the preceding claims.

   10) A method for the control of arthropods on soyabean which comprises administering to the soyabean plant an effective amount of a composition according to any of the preceding claims.

   11) A process for preparing an insecticidal composition which comprises the combination of an organophosphorous, pyrethroid, pyrethrin and/or lipid amide insecticide with piperonyl butoxide and a gallic acid ester in a ratio of 3:1 to 1:10.