Use of flufenacil amide for reducing or preventing bacterial propagation

Abstract

The present invention relates to the use of Tinoxamid for reducing or preventing the propagation of bacteria from an insect vector to a plant, and to methods for reducing or preventing the propagation of bacteria from an insect vector to a plant by applying Tinoxamid.

Description

[0001] manual

[0002] The present invention relates to the use of methoprene for reducing or preventing the transmission of bacteria from insect vectors to plants and protecting plants from bacterial diseases.

[0003] 1-[(1RS)-1,2-dimethylpropyl]-N-ethyl-5-methyl-N-pyridazin-4-yl-1H-pyrazole-4-carboxamide having formula I:

[0004]

[0005] Known from WO 2012 / 143317, this compound is mentioned as being useful against a wide variety of invertebrate pests. It is known by the common name methipridax.

[0006] Vectors are organisms that can introduce pathogens (such as viruses or bacteria) into plants through feeding, causing infection. Such insect vectors include, for example, Hemiptera, Thysanoptera, and Acarina species such as aphids, whiteflies, leafhoppers, planthoppers, treehoppers, thrips, mites, scale insects, mealybugs, mites, plant lice, and psyllids, which can also cause direct feeding damage to plants. The transmission of diseases from vectors to plants is a common cause of plant damage, for which there are few effective control measures.

[0007] Until now, the only effective means of reducing vector-borne bacterial infections has been to control the vectors, for example through the use of insecticides, to prevent infections before they occur. The use of antibiotics in agriculture is not universally accepted due to their selective activity against certain bacteria, their curative nature, and their potential to cure only when the disease is already present, with significant implications for human health and antibiotic resistance.

[0008] Insecticides, used alone or in combination with other known pesticides, are known to be useful in reducing infections spread by vectors (insects). However, the effectiveness of these insecticides or insecticide mixtures in reducing the spread of diseases from insect vectors to plants is not always satisfactory.

[0009] This is because insect vectors are often able to transmit diseases before insecticides can kill them. It is important to note that by the time insect vectors, such as Hemiptera (e.g., aphids, whiteflies, leafhoppers (particularly Cicadellidae) and planthoppers (particularly Cixiidae)), pass through a plant and briefly probe, by the time the insects receive a lethal dose of the insecticide, pathogen transmission is often complete and damage has already occurred. Therefore, there is a need for insecticides that not only kill the insect vectors, but primarily, quickly stop the insect vectors from feeding, which can reduce or stop the vectors' ability to acquire and transmit pathogens before the plant becomes infected. This rapid stopping of the insect vectors from feeding by appropriate insecticides not only helps reduce the severity of the disease on the affected plants, but also helps reduce the spread of the disease to other plants in the field. Therefore, there is a need for insecticides that can effectively reduce or stop the ability of insect vectors to transmit disease-causing pathogens.

[0010] We have found that this need is met by applying methoprene to the plants.

[0011] Furthermore, some insecticides have been observed to unsettle insects and stimulate them to move and feed more, leading to increased bacterial proliferation. Therefore, there is a need for insecticides that inhibit the movement and / or feeding of insect vectors before killing them. We have discovered that applying methiprad to crops satisfies this need.

[0012] There is a general need to reduce the dosage rate of insecticides, and this is also relevant for combating insect vectors. Therefore, there is also a need for insecticides that can be applied at lower dosages than conventional insecticides. We have found that this need can be met by applying methoxam to crops.

[0013] It is therefore an object of the present invention to provide an insecticide that satisfies any of the above needs. Surprisingly, it has been found that methoxazole is suitable for reducing or preventing the transmission of bacteria from insect vectors to plants. Methoxazole controls insect vectors at all developmental stages, in particular whiteflies, aphids, leafhoppers and planthoppers (e.g., Cicadidae such as Pentastirius sp.).

[0014] Thus, the present invention relates to the use of methoxam or its stereoisomers, tautomers, salts or N-oxides for reducing or preventing the spread of bacteria from insect vectors to plants. The present invention further relates to a method for reducing or preventing the spread of bacteria from insect vectors to plants, the method comprising the steps of contacting a plant, part thereof, its propagation material, insects, its food supply, habitat or breeding ground with a pesticidal effective amount of methoxam or its stereoisomers, tautomers, salts or N-oxides. All embodiments and preferences described throughout this document are valid for the purposes and methods of use of the present invention.

[0015] The comments made about preferred embodiments of the use or method according to the invention are to be understood as being preferred both individually and preferably in combination with one another.

[0016] As used herein, the term "pathogen" includes bacteria, such as phytoplasmas.

[0017] As used herein, the term "bacterial transmission from insect vectors to plants" refers to the introduction of pathogens into plants, leading to infection. Such transmission is typically characterized by acquisition time (i.e., the time required for an insect vector to acquire the pathogen), inoculation time (i.e., the time required for an infective insect vector to infect a plant), incubation period (i.e., the shortest time between acquisition of the pathogen and the insect vector being able to transmit the pathogen), and retention time (i.e., the time during which the insect vector is still able to transmit the bacteria after acquisition). Due to the reduction in bacterial transmission from insect vectors to plants, insect-mediated bacterial infection of field plants can be reduced. The primary spread of pathogens (i.e., the first spread of pathogens into the field by infective insect vectors from sources other than the field) and / or the secondary spread of pathogens (i.e., the spread of pathogens in the field by insect vectors from pathogen sources in the field, and the spread of pathogens by these subsequent infective insect vectors) can be reduced.

[0018] As used herein, the term "bacterial infection" or "bacterial infection" in relation to plants means that the plant has been infected with bacteria. As outlined above, bacterial infection is typically caused by inoculation of an infectious insect vector. Transmission of bacteria from an insect vector to a plant typically results in a bacterial infection.

[0019] The term "plant" refers to multicellular photosynthetic eukaryotic life forms belonging to the kingdom Plantae, including crop plants.

[0020] The term "crop" refers to plants grown for food or other commercial purposes. Applying thiophanate-methyl to a crop is a preferred embodiment of the present invention. Applying thiophanate-methyl to a sugar beet or potato crop is a particularly preferred embodiment of the present invention. In one embodiment, the crop is a sugar beet crop.

[0021] As used herein, the term "infectious insect vector" refers to an insect vector that has acquired the bacteria and can transmit the bacteria, meaning that the incubation period has ended, but the retention period has not.

[0022] The insect vectors in the present invention are preferably of the suborder Cephalochordata (such as the suborder Fulgoromorpha and the suborder Cicadomorpha, in particular the family Cicadidae and the family Cicadidae), and more preferably of the genera Amarasca, Apartus, Circulifer, Cixius, Dalbulus, Empoasca, Hyalesthes, Myndus, Reptalus, Scaphoideus, Tachycixius and Trigonocranus.

[0023] As used herein, the term "uninfected" with respect to plants means that the plants are healthy, i.e., not infected by bacteria. "Uninfected plants" may also be referred to as "bacteria-free plants." Mefenoxam is preferably used in fields containing only uninfected plants, focusing on reducing or preventing the primary spread of bacteria, or in fields containing both infected and uninfected plants, focusing on reducing or preventing the secondary spread of bacteria.

[0024] As used herein, the term "non-infectious" in relation to an insect vector means that the insect vector is not able to transmit the bacteria, and preferably, the insect vector does not even acquire the bacteria.

[0025] The term "contact" includes direct contact (applying the compound / composition directly to the animal pest or plant - typically to the foliage, stems or roots of the plant) and indirect contact (applying the compound / composition to the locus of the animal pest or plant, i.e., the habitat, breeding ground, plant, seed, soil, area, material or environment where the pest is growing or may grow). Maximum contact involves the combined application of methiprad to the pest and the plant.

[0026] "Pesticidally effective amount" means the amount of active ingredient required to achieve an observable effect on growth, including necrosis, feeding cessation, mortality, retardation, prevention, and effects that eliminate, destroy, or otherwise reduce the presence and activity of the target organism. The pesticidally effective amount of the composition will also vary depending on prevailing conditions, such as the desired pesticidal effect and duration, climate, target species, location, and mode of application.

[0027] By "reducing the spread of bacteria" is meant that the number of infected plants is reduced by at least 50%, or 65%, preferably 80%, especially 90%, or 95% compared to untreated controls.

[0028] "Prevention of the spread of bacteria" means that the number of infected plants is reduced by at least 90%, preferably at least 95%, more preferably at least 99%, especially preferably 100% compared to untreated controls.

[0029] While it is known that methoprene by itself and in combination with other insecticides has shown activity against insect pests, it is not known whether it can solve problems caused by bacteria in plants, especially sugar beets, potatoes, strawberry plants and olive trees as mentioned above.

[0030] The salt of thiophanate-methyl is preferably an agriculturally and veterinarily acceptable salt. Such salts and their preparation are generally known from WO 2012 / 143317. thiophanate-methyl can be used in the form of its N-oxide. Its N-oxide is generally known from WO 2012 / 143317.

[0031] Methimazole can be amorphous or can exist in one or more different crystalline states (polymorphs) that may have different macroscopic properties such as stability or show different biological properties such as activity. The present invention includes the use of amorphous and crystalline compounds, enantiomers or diastereomers thereof, mixtures of different crystalline states of methimazole, enantiomers or diastereomers thereof, and amorphous or crystalline salts thereof. In one embodiment, methimazole is in the crystalline form described and claimed in WO 2020144308, especially as disclosed in Examples 1-4.

[0032] Methifopamide is suitable for reducing or preventing the spread of pathogens from insect vectors to plants. Methifopamide is particularly suitable for effectively controlling and preventing the spread of pathogens by vectors of the suborder Cephalochorhynchidae. Cephalochorhynchidae and vector-borne bacterial diseases can cause serious damage to different crop cultures (such as sugar beet, potato, strawberry plants, vegetables, grapes and olive trees, especially sugar beet and potato). Methifopamide treatment is particularly useful for the families Cicadidae and Cicadidae.

[0033] Planthoppers (Ciliidae) are a family of insects in the order Hemiptera (the stink bugs). They belong to the suborder Cephalochorhynchidae, along with smaller springtails such as leafhoppers (Cicadidae) and hoppers or puffers (Cicadoidea).

[0034] The suborder Cephalochorhynchus includes the suborders Cicadae and Cicadae. Examples of insect vectors in the suborder Cephalochorhynchus include the genera Apa, Ambracidae, Ambracidae, Ambracidae, Ambracidae, Ambracidae, and Ambracidae. In one embodiment, the insect vector is an insect of the suborder Cicadae. In another embodiment, the insect vector is an insect of the superorder Membracoidea. In another embodiment, the insect vector is an insect of the family Cicadidae. In another embodiment, the insect vector is an insect of the genus Ambracidae. In one embodiment, the insect vector is an insect of the suborder Cicadae. In another embodiment, the insect vector is an insect of the family Cicadidae. In another embodiment, the insect vector is an insect of the genus Pentastiridius. In a preferred embodiment, the insect vector is the reed Ambracidae (Pentastiridius leporinus). In another embodiment, the insect vector is the Apa leafhopper (Apartus michalki). In another embodiment, the insect vector is the alpine leafhopper (Cixius alpestris). In another embodiment, the insect vector is Cixius beieri. In another embodiment, the insect vector is Cixius cambricus. In another embodiment, the insect vector is Cixius cunicularius. In another embodiment, the insect vector is Cixius distinguendus. In another embodiment, the insect vector is Cixius dubius. In another embodiment, the insect vector is Cixius heydenii. In another embodiment, the insect vector is Cixius nervosus. In another embodiment, the insect vector is Cixius similis. In another embodiment, the insect vector is Cixius simplex. In another embodiment, the insect vector is Cixius sticticus. In another embodiment, the insect vector is Cixius stigmaticus. In another embodiment, the insect vector is Cixius wagneri. In another embodiment, the insect vector is the yellow-legged clearwing leafhopper (Hyalesthes luteipes). In another embodiment, the insect vector is the hidden clearwing leafhopper (Hyalesthes obsoletus). In another embodiment, the insect vector is the philesakis clearwing leafhopper (Hyalesthes philesakis). In another embodiment, the insect vector is the variegated waxhopper (Myndus musivus).In another embodiment, the insect vector is Pentastiridius beieri. In another embodiment, the insect vector is Reptalus cuspidatus. In another embodiment, the insect vector is Reptalus panzeri. In another embodiment, the insect vector is Reptalus quinquecostatus. In another embodiment, the insect vector is Tachycixius pilosus. In another embodiment, the insect vector is Tachycixius venustulus. In another embodiment, the insect vector is Trigonocranus emmeae. In another embodiment, the insect vector is Homalodisca vitripennis. In another embodiment, the insect vector is Dalbulus maidis. In another embodiment, the insect vector is Amrasca biguttula. In another embodiment, the insect vector is Emporasca sp. In another embodiment, the insect vector is Scapohideus titanus.

[0035] Methifopamide has been found to be suitable for reducing or preventing the spread of bacteria from insect vectors to a number of crops, including but not limited to potatoes, sugar beets, grapes, and strawberry plants. Methifopamide controls vectors of the suborder Cephalochorhynchidae at all developmental stages, particularly the suborder Cephalochorhynchidae (such as Cyperus rabbitii and Cyperus welchii), as well as the suborder Cicadae (such as the glassy-winged leafhopper).

[0036] In one embodiment, the insect vectors are selected from aphids, whiteflies, leafhoppers, thrips, psyllids, scale insects, mealybugs, planthoppers (e.g., Cicadidae) and mites, and are preferably selected from the group consisting of aphids, whiteflies, leafhoppers, planthoppers (e.g., Cicadidae) and thrips, more preferably selected from the group consisting of aphids, whiteflies, Cicadidae and thrips, and in particular selected from the group consisting of Cicadidae, aphids and whiteflies, e.g., Cicadidae spp.

[0037] In another embodiment, the insect vector is selected from the family of Cicadidae and leafhoppers, and is preferably selected from the group consisting of Apa, Cicadidae, Transparent-winged, Mancicadidae, Pentathocera, Ruiji Cicadidae, Velocicadidae and Triangle-headed Cicadidae, more preferably from species of the genus Pentathocera, and in particular the rabbit Pentathocera.

[0038] In particular, the bacteria can be transmitted by the suborder Cephalochorhynchus, such as one or more of the following: Cyperus raptorus (Cercidiidae), Circulifer tenullus, and Agallianopsis agallianaensigera.

[0039] Plants exhibiting cephalopod or aphid damage may have symptoms such as reduced growth rate, leaf mottling, sooty mold growth due to secondary infection caused by honeydew production, yellowing, stunted growth, leaf curling, browning, wilting, poor yield, and death.

[0040] The loss of sap can lead to a lack of plant vigor. Additionally, cephalochordates often transmit pathogenic organisms such as bacteria to their hosts through feeding.

[0041] Similarly, whiteflies and cicadidae nymphs and adults feed by inserting their proboscises into leaves, penetrating the phloem and extracting sap. It is during this feeding process that plant pathogens are acquired and transmitted. In particular, adult whiteflies and cicadidae can disperse and transmit bacteria to new plants while feeding. Whiteflies are representatives of bacterial vectors and include whiteflies of the genera Bemisia and Trialeurodes. Particularly important species of the genus Bemisia include the whitefly (B. tabaci). Important species of the genus Aleyrod include the greenhouse whitefly (T. vaporariorum), the whitefly (T. abutilonea) and the whitefly (T. ricini). Whiteflies (Bemisia tabaci). Whiteflies frequently infest tomatoes, eggplants, tobacco, beans and peppers, while cicadidae and cicadidae frequently infest potatoes and sugar beets. In another particularly preferred embodiment of the present invention, the whitefly insect vector is selected from the group consisting of Bemisia tabaci, Whitefly (Trialeurodes vulgaris), Whitefly (Trialeurodes striata) and Whitefly (Trialeurodes ricinus), in particular, the whitefly insect vector is Bemisia tabaci. In another particularly preferred embodiment of the present invention, the vector is Cyperus raptorus.

[0042] The bacteria can also be spread by psyllids such as the Asian citrus psyllid (Diaphorina citri), which primarily causes a bacterial disease called citrus greening disease, or Huanglongbing (HLB).

[0043] The corn leafhopper (Cyprinus zeae) is primarily responsible for bacterial diseases (Spiroplasma zeae (CSS) and Maize Bushy Dwarf Phytoplasma (MBSP)).

[0044] Grape leafhoppers spread grape yellows phytoplasma (FDp), causing FD grapevines or grapevine yellows (GY); rabbit five-breasted waxhoppers spread low sugar syndrome (SBR); beet leafhoppers can spread phytoplasma / citrus stubborn disease spiroplasma (spiroplasma citri), causing curled top disease.

[0045] The reed-winged rabbit, the five-breasted wax cicada, primarily causes the bacterial disease Sugar Low Bacteria Syndrome (SBR) of sugar beet (Beta vulgaris subsp. vulgaris). Sugar beet plants exhibiting SBR may have various symptoms, such as widespread yellowing of leaves, lanceolate shaped young leaves, and necrotic discoloration visible in the vascular ring area.

[0046] SBR diseases are caused by the bacteria Candidatus Arsenophonus phytopathogenicus and stolbur phytoplasma (also known as Candidatus Phytoplasma solani (solanium stolbur)), which are transmitted to sugar beets by the reed vine, the five-breasted wax cicada. The first symptoms of sugar beets are visible at the end of summer. Older leaves show yellowing between the veins. Newly sprouted leaves are very light to faded and lanceolate in color. In most SBR-infected sugar beets, the beet body shows browning of the vascular bundles and glassy and translucent parenchyma tissue. A serious consequence of the disease is that the sugar content of the beet is significantly reduced, and the extraction of sugar leaves also deteriorates. Therefore, in one embodiment, the bacterium is Stolbur phytoplasma solani.

[0047] The reed cleaver, Cyperus quinquefasciatus, also causes the bacterial disease SBR of potato, characterized by lateral shoot sprouting, wilting, and rubbery tubers.

[0048] Strawberry marginal chlorosis is caused by a gammaproteobacterium in the Andrococcus clade. The causative agent is the tentative species Candidatus Phlomobacter fragariae, transmitted by the planthopper Candidatus fragariae of the family Candidae. Symptoms include leaflets, hyperplasia, fruit deformities, and chlorotic leaf margins.

[0049] Meadow Foliar Glasswing leafhopper (Homalodisca vitripennis) primarily targets olive trees and causes Olive Quick Decline Syndrome (OQDS). OQDS is olive tree A wasting disease that causes damage to leaves, twigs, and branches dead So that the olive trees no longer produce olives crops. The main cause of disease is bacteria Xylella fastidiosastrains, which are transmitted by plant-feeding insects such as grassland Cicada )spread. bacteria Restricted within the tree sap Symptoms include Leaf scorch and twig and branch dryness, starting in the upper crown and spreading to the rest of the tree, giving it a charred appearance.

[0050] Similarly, methoprene can be used to prevent or reduce the spread of bacteria by the following insect vectors: pea aphid (Acyrthosiphum pisum), apple aphid (Aphis citricola), bean aphid (Aphis craccivora), broad bean aphid (Aphis fabae), charcoal buckthorn aphid (Aphis frangulae), soybean aphid (Aphis glycines), cotton aphid (Aphis gossypii), buckthorn potato aphid (Aphis nasturtii), apple aphid (Aphis pomi), spiraea aphid (Aphis spiraecola), eggplant aphid (Aulacorthum solani), plum short-tailed aphid (Brachycaudus helichrysi), cabbage aphid (Brevicoryne brassicae), wheat two-tailed aphid (Diuraphis noxia), rose leaf roller aphid (Dysaphis devecta), plantain round-tailed aphid (Dysaphis plantaginea), apple woolly aphid (Eriosoma lanigerum), Hyalopterus pruni, Lipaphis erysimi, Macrosiphum avenae, Macrosiphum euphorbiae, Macrosiphum rosae, Myzus cerasi, Myzus nicotianae, Myzus persicae, Nasonovia ribis nigri, Pemphigus bursarius, Phorodon humuli, Rhopalosiphum insertum Wa, Rhopalosiphum maidis, Rhopalosiphum padi, Schizaphis graminum, Sitobion avenae, Toxoptera aurantii), citrus black aphid (Toxoptera citricola), grape phylloxera (Phylloxera vitifoliae), Bemisia tabaci, brown planthopper (Nilaparvata lugens), white-backed planthopper (Sogatellafurcifera), Laodelphax spp., black-tailed leafhopper (Nephotettix spp.), greenhouse whitefly, tobacco thrips (Thrips tabaci), palm thrips (Thrips palmi), potato psyllid (Bactericeracockerelli), corn yellow-winged leafhopper (Dalbulus maidis), comb flower thrips (Frankliniella schultzei), western flower thrips (Frankliniella occidentalis), rabbit five-breasted waxhopper, beet leafhopper, grapevine leafhopper (grape band leafhopper) and citrus psyllid.

[0051] One aspect of the present invention relates to a method for controlling Cephalochorhynchus, preferably Cephalochorhynchus, especially Cephalochorhynchidae and in particular Cephalochorhynchidae, comprising the steps of contacting a plant, part thereof, propagation material thereof, insects, their food supply, habitat or breeding ground with a pesticidally effective amount of methiprad.

[0052] For use in effectively controlling insects in potato, sugar beet, vegetable, grape or strawberry fields, or in olive trees, for example by foliar application, the application rate of the active ingredient of the present invention may be in the range of 0.01 g to 500 g per hectare, for example 1 g to 300 g per hectare or 1 g to 175 g per hectare, ideally 1 g to 100 g per hectare.

[0053] In particular, the application of methoprena has been shown to be effective in reducing or preventing both primary and secondary bacterial spread by insect vectors. On the one hand, it has been found that bacterially infected vectors, when landing on plants treated with methoprena, exhibit a reduced ability to transmit the bacteria. On the other hand, it has been found that uninfected insect vectors, when landing on infected plants treated with methoprena, have a reduced ability to transmit the bacteria to adjacent healthy plants.

[0054] Thus, in one aspect, the present invention relates to the use of methoprenaline for reducing or preventing the transmission of bacteria from insect vectors to plants.

[0055] In another aspect, the present invention relates to a method for reducing or preventing the spread of diseases from insect vectors to plants, the method comprising applying methoxam to the insect vectors, crops, plants, plant propagation materials such as seeds, or the soil or water in which the plants are grown. One embodiment of the present invention relates to the use of methoxam for reducing or preventing secondary spread. In another aspect, the present invention relates to a method for protecting plants from bacterial diseases, the method comprising applying methoxam to uninfected crops, plants, plant propagation materials such as seeds, or the soil or water in which the plants are grown.

[0056] In one embodiment, the present invention relates to a use or method for reducing or preventing the spread of pests from insect vectors to plants, such as sugar beet or potato plants, comprising applying to the plants a pesticidally effective amount of methiprad or a stereoisomer, tautomer, salt or N-oxide thereof.

[0057] In another embodiment, the present invention relates to a use or method for reducing or preventing the spread of pests from insect vectors to strawberry plants or olive trees, comprising applying a pesticidally effective amount of methiprad or its stereoisomers, tautomers, salts or N-oxides to the respective plants.

[0058] In another embodiment, the present invention relates to a use or method for reducing or preventing the spread of pests from insect vectors to corn or citrus plants, comprising applying a pesticidally effective amount of methiprad or its stereoisomers, tautomers, salts or N-oxides to the respective plants.

[0059] In a preferred embodiment of the use or method of the present invention, methipridafloxacin is applied to a field of uninfected plants, i.e. a field comprising only uninfected plants, i.e. a field that does not contain any plants infected by the bacteria. Thus, the initial spread of the bacteria can be reduced or even prevented, since methipridafloxacin will prevent or significantly reduce feeding (spread) by existing and incoming insect vectors.

[0060] In another preferred embodiment of the use or method of the present invention, methoxazole is applied to a field comprising both infected and uninfected plants. This is particularly useful for reducing or preventing the secondary spread of bacteria in the field.

[0061] Most plant pathogens belong to the genera Erwinia, Arsenophonus, Phlomobacter, Serratia marcescens, Pectobacterium, Pantoea, Agrobacterium, Liberibacter, Pseudomonas, Ralstonia, Burkholderia, Acidovorax, Xanthomonas, Clavibacter, Streptomyces, Xylella, Spiroplasma, and Phytoplasma. Xylella, Basilicum, Spiroplasma, and Phytoplasma species contain the most economically important diseases transmitted by Hemiptera vectors in plants (Huang, Weijie PMC December 28, 2020). Preferred embodiments of the use or method according to the invention for reducing or preventing bacterial transmission from insects, particularly those vectored by the suborder Cephalochordae, to sugar beet or potato crops are described herein, comprising applying fenthiocarp.

[0062] Since bacteria are known to be acquired by infected plants in two vasculatures: the phloem and the xylem, it is assumed that most bacterial diseases (e.g., by insect vectors) will be obligate intercellular persistents and semi-persistents, cyclical and non-cyclical, with a minority being non-persistents. It should also be noted that bacterial acquisition within plants may also occur via contaminated soil or seeds, plant damage exposed to infected debris, or airborne spores. Several families that affect plant health also contain genera and / or species that affect human (mammalian) health.

[0063] In one embodiment of the invention, the pathogen is a persistent bacterium. In another embodiment, the bacterium is a non-persistent bacterium. In another embodiment, the bacterium is a semi-persistent bacterium.

[0064] One embodiment of the present invention relates to the use of methoprena to reduce or prevent the spread of non-persistent bacterial species. Another embodiment of the present invention relates to the use of methoprena to reduce or prevent the primary spread of non-persistent bacterial species by rapidly stopping feeding. Another embodiment of the present invention relates to the use of methoprena to reduce or prevent the secondary spread of non-persistent bacterial species.

[0065] One embodiment of the present invention relates to the use of methoprena to reduce or prevent the spread of persistent bacterial types. Another embodiment of the present invention relates to the use of methoprena to reduce or prevent the primary spread of persistent bacterial types by rapidly stopping feeding. Another embodiment of the present invention relates to the use of methoprena to reduce or prevent the secondary spread of persistent bacterial types.

[0066] Another embodiment of the present invention relates to the use of methoprene for reducing or preventing the primary spread of non-persistent and semi-persistent bacterial types. Another embodiment of the present invention relates to the use of methoprene for reducing or preventing the secondary spread of non-persistent and semi-persistent bacterial types.

[0067] To reduce secondary spread, insecticides are needed that effectively kill all insect vectors or rapidly stop the vectors from feeding. However, fast-kill insecticides can negatively impact non-target arthropods and beneficial organisms. Mefenoxam has been found to effectively cause a rapid cessation of insect feeding through its unique mode of action. Thus, mefenoxam controls bacterial spread by preventing infection of plants during feeding.

[0068] In one embodiment, the bacteria are selected from the family Mycoplasmataceae, Acholeplasmataceae, Rhizobiaceae, and preferably from the genera Spiroplasma, C. Phytoplasma, and C. phytoplasma, respectively. In one embodiment, the bacteria are selected from the family Enterobacteriaceae, in the order Enterobacteriales. In another embodiment, the bacteria are selected from the species Spiroplasma.

[0069] The Erwiniaceae family contains the genus Erwinia, which includes over 20 species, the most common of which is probably E. amylovora, or fire blight, which occurs on pome and stone fruits. In addition, there is Erwinia tracheiphila, which causes bacterial wilt in cucurbits and ornamental plants such as orchids. And the subgenus Pantoea contains at least 9 species, some of which are opportunistic and can affect humans. The most common, P. stewartia, causes Stewart's wilt, bacterial leaf blight, rice leaf blight, and jackfruit bronzing disease in corn and other grasses such as sugarcane.

[0070] The Pectobacteriaceae family includes the genera Dickea, Brenneria, and Pectobacterium, each with eight to nine species. Dickea solanani is a common example of a bacterium that affects potatoes and other Solanaceae crops, often known as blackleg or soft rot.

[0071] The Rhizobium family has over 20 genera, including but not limited to Agrobacterium and Drosophila. Agrobacterium is best known for forming gall-like growths in a range of row crops (such as soybean, cotton, maize, etc.) and for use in GMO transformation. Drosophila is best known for its semi-persistent presence, hemolymph, and salivary glands in psyllids, potatoes, and the Asian citrus psyllid, transmitting zebra flake disease in potatoes and Solanaceae crops, and Huanglongbing (HLB), or fruit greening disease, in citrus.

[0072] Pseudomonas is a genus of the Pseudomonadaceae family that expresses a range of plant diseases with common symptoms of rot, gall formation, and necrosis and contains plant growth-promoting saprophytic Pseudomonas pyogenes (PGPP).

[0073] The Burkholderiaceae family comprises two major plant-infecting genera, Ralstonia and Burkholderia, which infect a wide range of Solanaceae crops, such as potato, eggplant, tomato, wild solanum, pepper, as well as soybean, ginger, and a range of ornamental plants, causing bacterial wilt.

[0074] The genus Burkholderia contains 20 or more species, including Burkholderia glumae, which causes grain and seedling rot in rice and blight in solanaceous crops and sesame, among others.

[0075] The Xanthomonadaceae family contains many species of Xanthomonas, nearly 30 species, which affect more than 400 different plant species. Plant responses range from citrus canker (caused by Xanthomonas citri) to bacterial leaf spot and bacterial wilt, such as Xanthomonas oryzae in rice. This family also includes the genus Xylella, which contains species of X. fastidiosa. X. fastidiosa is commonly vectored by leafhoppers (such as the sharpshooter) and other Hemiptera. Many diseases are associated with a variety of crops, including but not limited to bacterial leaf blight in oleander and coffee, alfalfa dwarfing, Pierce's disease in grapes, olive rapid decline syndrome in olive trees, and citrus variegated chlorosis in citrus.

[0076] Corynebacterium species of the Microbacteriaceae cause bacterial canker or ring rot via Clavibacter michiganensis, which affects Solanaceae crops, including tomatoes.

[0077] The genus Streptomyces of the family Streptomycetaceae has at least 10 plant pathogenic species, but over 500 species in this family can cause damage to tuber and root crops (such as Solanaceae crops, potatoes) via S. scabies, but the genus is typically associated with soil-borne pathogens rather than vector-borne pathogens.

[0078] The genus Xylella comprises over 600 species that affect plants. Disease symptoms include leaf chlorosis, wilting, changes in internode growth, changes in fruit size and shedding, and a sticky leaf appearance. For example, Xylella fastidiosa is an aerobic plant pathogen that lurks in xylem tissue and is spread by xylem-feeding insects such as leafhoppers / sharpshooters and spitting insects, causing chlorosis, leaf scorch, and other symptoms. A particular consequence is Pierce's disease (PD) in grapes.

[0079] The genus Spiroplasma, family Spiroplamataceae, and class Mollicutes, includes several pathogens that cause disease in plants but are also capable of infecting mammals and forming symbiotic associations with the same species (i.e., Drosophila), protecting against parasitic nematodes, or acting as drivers of speciation, affecting other arthropods including ladybugs, bees, ants, beetles, and butterflies by killing males. The crop disease focus is on Spiroplasma citrus, which causes citrus stubborn disease, and Spiroplasma kunkelii, which causes maize dwarf disease.

[0080] The genus Phytoplasma also belongs to the class Mollicutes and includes the genus Candidatus, which affects a wide range of crops, including but not limited to tropical fruits (e.g., coconut), drupes, sugarcane, and woody trees, and is most commonly mediated by Hemiptera pests. Phytoplasmas are obligate phloem tissue pathogens that require insect vectors for plant-to-plant transmission. A specific example of economic importance is the tentative species of phytoplasma (Candidatus phytoplasma) mediated by the corn leafhopper, the corn yellow-winged leafhopper, which causes maize bushy dwarf disease. Another example is the tentative species of plant pathogenic male-killing bacteria mediated by the rabbit five-breasted waxhopper (Candidae), which causes low sugar syndrome (SBR). In one embodiment, the bacterium is a tentative species of plant pathogenic male-killing bacteria. In another embodiment, the present invention relates to a use or method for reducing or preventing the spread of bacteria to plants and protecting plants from bacterial diseases, the method or use comprising applying amethoxazole, wherein the bacterium is selected from the group consisting of corn dwarf spiroplasma and tentative species of phytoplasma.

[0081] By the inventive use of methoprena or the method of applying methoprena to plants (both uninfected and infected plants), plant diseases caused by the above-mentioned bacterial genera can be reduced or prevented, or the above-mentioned plants can be protected.

[0082] For some bacteria, certain insect vectors can be identified. For example, if the insect vector is a leafhopper, such as the corn yellow-winged leafhopper, bacteria such as Zea mays (a Mollicutes bacterium) and maize bushy dwarf phytoplasma (MBSP) can be transmitted. HLB (Hemiptera: Hyaluronic acid) is transmitted by the Asian citrus psyllid (Diaphornia citri).

[0083] Flavescence dorée (FD-C and FD-D) is caused by the grape leafhopper.

[0084] In a preferred embodiment of the present invention, the plant is selected from the group consisting of alfalfa, barley, beans, beets, Brassicas, cabbage, carrots, cauliflower, celery, cherries, chickpeas, clover, coriander, courgettes, cucumbers, gourds, eggplants, beans, fodder beets, gherkins, lentils, lettuce, alfalfa, lupines, maize, zucchini, melons, mustard, oats, rapeseed, ornamentals, parsley, parsnips, peas, peppers, potatoes, pumpkins, quinoa, radishes, rapeseed, rice, safflower, soybeans, spinach, squash, sugar beets, tobacco, tomatoes, triticale, turnips, watermelons and wheat. In a particularly preferred embodiment of the present invention, the plant is selected from the group consisting of: tomato, eggplant, potato, tobacco, bean, pepper, rape, Physalis, Brassica, lettuce crops, mustard, chickpea, lupine, lentil, bean, pea, alfalfa, clover, barley, wheat, oats, maize, triticale, rice, sugar beet and fodder beet. In another embodiment, the plant is a sugar beet plant. In another embodiment, the plant is a potato, sugar beet and fodder beet plant.

[0085] In one embodiment, the present invention relates to a use or method for reducing or preventing the spread of bacteria to plants and protecting plants from bacterial diseases, the method or use comprising applying methoprene, wherein the plant belongs to the grass family, preferably maize (also known as corn).

[0086] A single embodiment of the present invention is a method or use for reducing or preventing the transmission of bacteria from an insect vector to a plant, wherein the insect vector, bacteria and plant are as defined in entries 1-1 to 1-9 of Table A.1, the method or use comprising applying methipram to the corresponding crop.

[0087] Table A.1

[0088] A single embodiment of the present invention is a method or use for reducing or preventing the transmission of bacteria from an insect vector to a plant, wherein the bacteria and the plant are as defined in entries AB-1 to AB-4 of Table A.2, the method or use comprising applying methoprene to the plant. A single embodiment of the present invention is a method or use for protecting a plant from a bacterial disease, wherein the bacteria and the plant are as defined in entries AB-1 to AB-4 of Table A.2, the method or use comprising applying methoprene to the plant.

[0089] Table A.2

[0090] serial number bacteria Affected crops AB-1 Zea mays dwarf spiroplasma corn AB-2 Tentative species of phytoplasma corn AB-3 Huanglongbing bacteria species (HLB) Tangerine AB-4 Grape yellowing disease (FDp) Grape

[0091] These bacteria are preferably spread by insects as defined above, for example by one or more leafhopper species like the corn yellow-winged leafhopper and / or the citrus psyllid.

[0092] A single embodiment of the present invention is a method or use for protecting plants from diseases including but not limited to bacterial diseases, wherein the primary affected plants / crops, bacteria, and transmitting insects are as defined in entries C-1 to C-5 of Table C, the method or use comprising applying methoprene to a field comprising uninfected or infected plants. The list is shortened to show economically important bacteria that are also associated with insect-based transmission.

[0093] Table C

[0094]

[0095]

[0096] Particular embodiments of the present invention are methods or uses for protecting corn plants from the spread of bacterial diseases including corn dwarf spiroplasma (CSS) caused by Spiroplasma maydis and maize bushy dwarf phytoplasma (MBSP) caused by the phytoplasma candidatus, the transmitting insect being the corn yellow-winged leafhopper (corn leafhopper), comprising applying methoxam to a field containing uninfected or infected plants.

[0097] Furthermore, it has been found that methoxazole is particularly suitable for the purposes of the present invention if applied in combination with another compound having pesticidal activity. Such combinations and mixtures are known, for example, from WO 2013 / 189801, WO 2016 / 128261, and WO 2018 / 234478.

[0098] The present invention therefore relates to a use or method for reducing or preventing the transmission of bacteria from Cephalochorhynchida vectors to plants, the method or use comprising applying methipridaxil in combination with at least one additional compound having pesticidal activity. Another aspect of the present invention relates to a method for protecting plants from bacterial diseases, the method comprising applying methipridaxil in combination with at least one additional compound having pesticidal activity.

[0099] The oxathiapiprolin used in the present invention can be used in conventional types of agricultural chemical compositions, for example, solutions, emulsions, suspensions, dusts, powders, pastes, granules, compressed formulations, capsules and mixtures thereof. Examples of composition types are suspensions (e.g., SC, OD, FS), emulsifiable concentrates (e.g., EC), emulsions (e.g., EW, EO, ES, ME), capsules (e.g., CS, ZC), pastes, pastilles, wettable powders or dusts (e.g., WP, SP, WS, DP, DS), compressed formulations (e.g., BR, TB, DT), granules (e.g., WG, SG, GR, FG, GG, MG), insecticide preparations (e.g., LN) and gel formulations (e.g., GF) for treating plant propagation materials (e.g., seeds). These and other composition types are known from WO 2012143317.

[0100] Agrochemical compositions generally contain between 0.01% and 95%, preferably between 0.1% and 90%, and most preferably between 0.5% and 75% by weight of active substance. The active substance is used in a purity of from 90% to 100%, preferably from 95% to 100%.

[0101] The user usually applies the composition according to the present invention by a pre-dosing device, a backpack sprayer, a spray can, a spray plane, or an irrigation system. Usually, the agrochemical composition is made into the desired application concentration by water, a buffer and / or another adjuvant, and thereby obtains the ready-to-use spray liquid or agrochemical composition according to the present invention. Usually, 20 to 2000 liters of ready-to-use spray liquid are applied per hectare of agricultural utilization area.

[0102] Application can be carried out before or after the crops, plants or plant propagation materials are infected by insect vectors. Preferably, application is carried out before the crops, plants or plant propagation materials are infected by insect vectors with bacteria.

[0103] Mefenoxam can be applied as such or in the form of compositions comprising them (preferably SL and SC formulations).

[0104] In a preferred embodiment of the use or method of the present invention, methoxazole is preferably applied to the foliage of the plant in an amount of from 20 g to 200 g per hectare, more preferably from 30 g to 150 g per hectare, for example from 90 g to 120 g or from 120 g to 150 g or from 30 g to 120 g per hectare.

[0105] In another embodiment of the use or method of the present invention, methoxazole is preferably applied to the seeds of the plant in an amount of from 1 g to 200 g per 100 kg of seeds, preferably from 5 g to 100 kg per 100 kg of seeds, for example from 10 to 30 g or from 40 to 60 g or from 70 to 90 g per 100 kg of seeds.

[0106] Examples

[0107] The present invention is illustrated in more detail by the following biological examples.

[0108] Examples from both laboratory and field settings show a strong trend toward greater reductions in the overall presence of relevant plant diseases in crop systems when methoprene is used prophylactically prior to natural or artificial infestation by vector insects, or curatively during periods of maximum plant-insect contact, compared to other insecticides. Based on feeding EPGs, honeydew clocks, and associated field trials, it was concluded that methoprene drives reduced feeding both during detection and during salivation or feeding. The relevance of these laboratory results is reflected in the reduction in overall disease presence, as visually noted, which was independent of the observed pest population.

[0109] Mefenamic acid was used as a 120 g / l SL formulation in experiments 1 to 5. The formulation was diluted with water to give a spray liquid for use in the following experiments.

[0110] Imidacloprid was used as a commercial formulation and dilution and application rates were according to its label. All treatments were applied using pressurized backpacks. Example 1: Disease Spread Reduction and Mortality in Control of Corn Yellow-winged Leafhoppers

[0111] As vectors of the two main pathogens that cause maize dwarf in corn (the Mollicutes bacteria Spiroplasma maize dwarf and Phytoplasma maize bushy dwarf), insects can be a major problem for growers because a period of time can pass before insecticides kill the insects, during which time the insects can transmit the disease to healthy plants. The bacterial vector relationship of the corn yellow-winged leafhopper (DALBMA) is a persistent one, meaning the insect can only transmit or acquire the disease if it feeds in the phloem vessels for an extended period. In this case, a good vectoricide needs to kill the insect but also quickly stop feeding activity to prevent disease transmission.

[0112] Maize (ZEAMX) plants of the variety AG 8480PRO3 were planted at normal spacing (row spacing 0.5 m, plant density 4 plants / m). The plot size was 6 x 6 m (36 m 2 ).

[0113] Treatment was carried out via foliar application 5 days after emergence and repeated every 5 days. The total number of applications during the trial period was 7. The spray volume was 120 L / ha and the nozzle used for application was an XR 110.02 with a spacing of 0.5 m between nozzles and a pressure of 2.5 bar. The average application time for the entire study ranged from about 30 to 50 minutes.

[0114] Compared to the commercial standards tested, using methipridax as a 120 g / L SL formulation:

[0115] Thiamethoxam + λ-cyhalothrin: Pleno 141g / L+106g / L SC (Syngenta);

[0116] Imidacloprid + Bifenthrin: 300 g / L SC (ADAMA) in the following proportions.

[0117]

[0118] Application Code describe Extended BBCH scale A 5 days after appearance 11 – The first leaf unfolds B 5 days after administration of A 15–5 leaves unfolded C 5 days after administration of B 19 – 9 or more leaves unfolded D 5 days after administration of C 30 – Stem elongation begins E 5 days after administration of D 35 – 5 nodes can be detected F 5 days after administration of E 39 – 9 nodes can be detected G 5 days after application of F 42–Tassels appear

[0119] Different assessments are conducted throughout the trial period:

[0120] Population: Count of surviving insects in the central 15 plants in a plot.

[0121] Infection: The central 15 plants in a plot were evaluated and rated according to the severity of stunting symptoms.

[0122] Level 1: Plants without symptoms

[0123] Level 2: Plants with less than 25% of leaves showing symptoms (red or yellow leaves)

[0124] Level 3: Plants with symptoms on 25%-50% of leaves

[0125] Level 4: Plants with symptoms on 50%-75% of leaves

[0126] Level 5: Plants with symptoms on more than 75% of leaves

[0127] Level 6: Plants die due to symptoms

[0128] Yield: Harvest yield (kg / ha)

[0129] Code Evaluation time description E05 5 days after administration of E F05 5 days after application of F G05 5 days after administration of G G10 10 days after administration of G G15 15 days after administration of G 099 Harvest

[0130]

[0131] Table 1-1: Results based on replicate means, subsamples per plot: Efficacy (%) control of yellow-winged leafhopper, stunt symptom severity (rating 1-6), and yield (kg / ha)

[0132]

[0133] The results show the effect of thiamethoxam treatment on the spread of bacterial diseases of corn yellow-winged leafhoppers on corn crops. The percentage of efficacy of thiamethoxam at a rate of 108 gai / ha for the control of yellow-winged leafhopper vector populations was shown to be comparable to the efficacy of imidacloprid + bifenthrin at G05 and G10, which were 17.8, 16.7 and 14.6, respectively. From E05 to G10, thiamethoxam at a rate of 120 gai / ha showed a higher efficacy than imidacloprid + bifenthrin and a lower efficacy than thiamethoxam + lambda-cyhalothrin, i.e., 41.5, 14.6 and 88.3, ​​respectively, at G10. The key attributes of thiamethoxam at 108 and 120 gai / ha were observed compared to the commercial standard by lower stunting symptom severity responses and higher yields by weight kg / ha. While thiamethoxam + lambda-cyhalothrin achieved a higher percentage efficacy against yellow-winged leafhopper populations throughout the study, it did not reduce symptom severity or harvested kg / ha to the same levels as methoprene. Compared to the untreated control, methoprene reduced stunt symptom severity by 2.5x at 108 gai / ha and by 3x at 120 gai / ha. The reduction in stunt symptoms correlated directly with the total harvested kernels by weight in the study, with methoprene treatments achieving approximately 1.4x the weight of the untreated control and thiamethoxam + lambda-cyhalothrin-treated plots and approximately 1.3x the weight of the imidacloprid + bifenthrin-treated plots. These results demonstrate the importance of rapid feeding cessation by methoprene in protecting crops and yields from plant disease infection.

[0134] Example 2: Bacterial transmission (EPG study)

[0135] The most powerful technique for studying the feeding behavior and plant penetration activity of sap-sucking insects is the electrosucking graph (EPG) technique (Tjallingii, Entomologia Experimentalis et Applicata [Experimental and Applied Entomology] 24:521-530 (1978); Entomologia Experimentalis et Applicata [Experimental and Applied Entomology] 38, 177-186 (1985)). An EPG is an electrical system in which, once an insect with piercing mouthparts inserts its mouthparts (stylet) into a plant, the insect and the plant become part of an electrical circuit. Voltage fluctuations are generated and can be recorded as waveforms, thereby monitoring the insect's feeding activity and the position of the stylet tip within the plant. These voltage fluctuations are due to changes in resistance (R) or electromotive force (emf) that occur during the stylet penetration process. EPG recordings allow real-time study of the stylet penetration activity of insect vectors and facilitate correlation of insect probing activity with inoculation or acquisition of various plant pathogens (Prado and Tjallingii, Entomologia Experimentalis et Applicata 72: 157-165 (1994); Jiang et al., Annals of the Entomological Society of America 93, 573-579 (2000); Bonani et al., Entomologia Experimentalis et Applicata 134, 35–49 (2010)). It has also been widely used to understand how compounds can affect the feeding behavior of sap-sucking insects (e.g., Harrewijn and Kayser, Pesticide Science 49, 130-140 (1997); Jacobson and Kennedy, Pest Management Science 70(5):836-40 (2014). EPG has also recently been used as a new tool to monitor the early stages of insecticide resistance in aphids (Garzo et al., Pest Management Science 72(4), 707-18 (2016)).

[0136] The experiments were performed using the EPG technique (Tjallingii 1978). EPG was used to show the effects on the feeding behavior of corn leafhoppers (Dalbama zea) on corn plants (Zea mays, ZEAMX) previously treated with the selected active ingredients. For these experiments, Stylet + d software connects an 8-channel DC-EPG (Giga-8dd) (potential sucking graph) divider to an A / D converter card and a personal computer for data acquisition and analysis. Waveform pathways monitored from corn leafhopper feeding output include: C = parenchyma pathway, G = feeding from the xylem, E1 = salivation into the phloem, and E2 = feeding from the phloem. The corn leafhopper vectors bacteria in a persistent manner, meaning the insects can only transmit or acquire the disease if they feed in the phloem vessels for extended periods. In this case, a good vectoricide would need to kill the insects but also halt feeding activity to prevent disease transmission.

[0137] Treatments were applied via foliar application. Each treatment had 10 replicates, with one insect per plant. Plants were sprayed with a gun sprayer at the recommended dosage, and after the plants dried, EPG plant setup was arranged. Corn leafhoppers were fixed under vacuum and on a cold plate, and attached to 17 μm gold wires with the aid of silver conductive paint.

[0138] The insects were then connected to copper electrodes and a DC-EPG setup. Plant electrodes were used to complete the circuit. EPG signals were collected from each insect on different plants, and at least 10 replicates per treatment were recorded, interpreted, and analyzed. All behavioral variables were processed using an in-house developed EPG Excel data worksheet.

[0139] DC-EPG (Giga-8dd) output is performed during continuous 24-hour recording.

[0140] Compared to the commercial standard Thiamethoxam + Lambda-cyhalothrin using methoxam as a 120 g / L SL formulation: Pleno 141g / L+106g / L SC (Syngenta).

[0141] Ratio of test compound:

[0142]

[0143] EPG results

[0144] Table 2-1: Total duration of each waveform (total probe, C, G, E1, and E2) during the 24-hour EPG recording analysis period

[0145]

[0146] Results showed that methoprene and other compounds had a strong effect on the feeding behavior of corn leafhoppers. The phloem is the vessel through which the corn leafhopper transmits dwarf disease to corn. The relationship between Mollicutes bacteria, phytoplasmas, and the vector is a persistent one, meaning the insect can only transmit or acquire the disease if it feeds in the vessel for an extended period. Methiprene had the lowest total detection time (minutes) across all tissues, most notably within the phloem, via salivation and feeding. When compared to the control, significant changes in feeding behavior were observed throughout the 24-hour period, with methoprene reducing the total time spent salivating and feeding in the phloem by 12x, 37x to 57x, and 6.9x, respectively. When compared to thiamethoxam + lambda-cyhalothrin, methoprene numerically reduced phloem salivation (E1) by approximately 2x and phloem feeding (E2) by 3x, confirming its interference with corn leafhopper feeding behavior.

[0147] Example 3: Feeding cessation rate – honeydew clock results for cotton aphid (APHIGO)

[0148] Stopping feeding is a key aspect of reducing disease transmission between plant hosts. Because the impact on insects is based on cooperation, active detection, feeding, and mortality, understanding the results of EPG studies and linking them to the tangible and direct output of feeding is key. Honeydew is a sugary excretion produced by piercing and sucking insects such as aphids and whiteflies and can be collected using water-sensitive paper to reveal active feeding over an isolation period of approximately 24-48 hours. Honeydew production is a direct indication of feeding per hour. Even if the insects persist on the plant and do not fully succumb to the treatment, reducing or inhibiting feeding during this period is crucial to reducing disease transmission.

[0149] To being in growth stage BBCH 12, the cotton plant of about 30-35cm is pre-pruned, to remove all leaves, only remaining one blade.This blade is further pruned, forms rectangular cross section along its middle vein, width is no more than 6-8mm, length is about 24mm, and by support by metal twist band on horizontal plane during experiment.In case finish pruning and support, just infest plant with cotton aphid, cotton aphid is to obtain from the colony of inside setting up via the dicotyledonous plant blade clipping that is infected in advance, and before processing, on plant material, stop about 12-24 hour.Before using, the aphid quantity of the plant / blade through pruning of each strain is evaluated, and in all processing, the aphid quantity of each strain plant is relatively similar.Use and make plant drying about 30 minutes.The treated plant is placed so that once dry, just treated blade is stopped at 2-3mm place above the moisture-sensitive paper strip that is attached to 24 hour rotating clock timer (Intermatic Time-All model TN111C or TN311C). The humidity-sensitive paper was coaxially mounted on the outer edge of a 60 mm petri dish lid using double-sided tape, which was then attached to the front of a 24-hour clock via Velcro. The replicated series was maintained on a seven-outlet power strip, which was clamped to a rectangular steel base for support. The setup was maintained under ambient laboratory conditions.

[0150] Treatments were applied via foliar application, where infested plants were dipped into a solution of a predetermined ratio (ppm ai or gai / ha) prepared by diluting the formulated compound in deionized water. Plant foliage was immersed in the solution for a full 3 seconds, ensuring complete coverage of the plant. The total number of replicates per treatment was 3, with a total number of 180-300 aphids per treatment.

[0151] Test compound: Pymetrozine 50% WG ( Syngenta), spirotetramat 240g / L OD ( Bayer) used methoxazole as a 120 g / LSL formulation.

[0152]

[0153] result

[0154] Table 3-1: Average total number of aphid honeydew droplets over 24-48 hours

[0155] Treatment + ratio gai / ha Average total number of droplets after 48 hours comparison 361.0 Mefenthrin 40 gai / ha 67.3 Pymetrozine 96g ai / ha 135.0 Spirotetramat 79gai / ha 327.0

[0156] Table 3-2: Average number of aphid honeydew droplets per hour measured over a 48-hour period

[0157] Treatment + ratio gai / ha Average number of droplets per hour comparison 22.7d Mefenthrin 40 gai / ha 6.0a Pymetrozine 96g ai / ha 7.7b Spirotetramat 79gai / ha 17.6c

[0158] Model = generalized linear mixed model with negative binomial distribution (log link) and autoregressive 1 covariance structure. P = 0.05.

[0159] Results showed that methoprene had a favorable effect on reducing honeydew production and the duration of honeydew cessation by cotton aphids (Aphis gossypii) on cotton compared to a relevant global commercial insecticide. Methiophanate-methyl demonstrated the lowest number of aphid droplets (67.3) over a 24–48 hour period. When the average number of droplets per hour was evaluated, methoprene-methyl showed a significant reduction, with the lowest number of honeydew droplets noted over the entire test period. The reduction in feeding, measured in terms of either hourly or total honeydew droplets, confirmed that methoprene exhibited feeding activity in a manner that correlated with reduced disease transmission.

[0160] Example 4: Control of Cyperus serratus in sugar beet plants

[0161] Sugar beet plants (BBCH 14) in pots were obtained from the University of Giessen. Plant hoppers were collected from fields in Rhineland-Palatinate, Germany. The plants were sprayed using an automated sprayer (HSSCAPR / DT, nozzle: Lu 120 02, pressure: 3 bar) from the BASF Agricultural Station in Limburgerhof. Treatments were performed according to Table 4-1.

[0162] deal with Application rate in grams of active ingredient per hectare Volume / hectare Control water - 300 Mefenamic acid 150 300

[0163] Table 4-1

[0164] After drying, the plants were placed in acrylic glass cylinders (diameter: 132 mm, height: 350 mm) and then placed on Petri dishes (diameter: 145 mm). The cylinders were covered with plastic mesh. Each plant was infested with 10 insects (mixed males and females). The plants were incubated at 23°C, 50% RH, and an 18-hour day / 6-hour night light cycle. Planthopper mortality was assessed on the first, fourth, and seventh days after infection (DAI). Table 4-2 lists the mortality rates for all application and observation time points:

[0165] comparison Mefenamic acid 1DAI 10 24 4DAI 32 52 7DAI 41 58

[0166] Table 4-2: Mortality of the rabbit-like schizont

[0167] Example 5: Disease spread reduction and mortality of corn yellow-winged leafhopper (Damicornis maydis; DALBMA) compared to methoprena – field study

[0168] The purpose of this experiment was to further understand the effects of methoprena treatment on the disease transmission of the corn yellow-winged leafhopper in corn crops.

[0169] The experiment was conducted at the following locations

[0170]

[0171] Maize plants were planted using normal spacing (row spacing 0.5 m, plant density 4 plants / m) of variety AG 8480PRO3. Plot size was 6 x 6 m (36 m 2 ). Treatment was carried out via foliar application 5 days after emergence and repeated every 5 days. The total number of applications during the test period was 7. The spray volume was 120 L / ha, and the nozzles used for application were XR 110.02, with a spacing of 0.5 m between nozzles and a pressure of 2.5 bar.

[0172]

[0173] Evaluation: Different evaluations are conducted throughout the trial period:

[0174] Population: Count of surviving insects in the central 15 plants in a plot.

[0175] Infection: The central 15 plants on the plot were evaluated and rated according to disease symptom level (severity).

[0176] Level 1: Plants without symptoms

[0177] Level 2: Plants with less than 25% of leaves showing symptoms (red or yellow leaves)

[0178] Level 3: Plants with symptoms on 25%-50% of leaves

[0179] Level 4: Plants with symptoms on 50%-75% of leaves

[0180] Level 5: Plants with symptoms on more than 75% of leaves

[0181] Level 6: Plants die due to symptoms.

[0182] Plant height (cm): Evaluate the plant height (cm) of the central 15 plants

[0183] Yield: Harvest yield (kg / ha)

[0184] Code Evaluation time description A05 05 days after administration of A B05 05 days after administration of B C05 05 days after application of C D05 05 days after administration of D E05 05 days after application of E G15 15 days after administration of G 099 Harvest

[0185]

[0186]

[0187] Ratio of test compound

[0188]

[0189] result:

[0190] Table 4-1 - Data results of field trials on efficacy (%), disease infection (grades 1-6), plant height (cm) and yield (kg / ha).

[0191]

[0192]

[0193] Efficacy (%) was calculated using the Henderson and Tilton formula based on the NUMBER evaluation.

[0194] Statistical analysis was performed using Friedman, Tukey, and Scott-Knott (5%).

[0195] Conclusion: Based on the efficacy data, methoprene was not statistically different from the other tested products. However, methoprene was statistically different from the other tested products (thiamethoxam + lambda-cyhalothrin and imidacloprid + bifenthrin) in infection, plant height, and yield evaluations. Based on the data, methoprene did not cause a strong knockdown effect (mortality), but through its different mode of action, it led to a decrease in feeding activity, thereby reducing disease transmission (the main cause of yield loss) and increasing plant height and ultimate yield.

Claims

1. 1-[(1RS)-1,2-dimethylpropyl]-N-ethyl-5-methyl-N-pyridazin-4-yl-1H-pyrazole-4-carboxamide (commonly known as thiamethoxam) of formula I: or a stereoisomer, tautomer, salt or N-oxide thereof for reducing or preventing the transmission of bacteria from an insect vector to a plant.

2. The use according to claim 1, wherein the insect vector is selected from the suborder Cicadae and the suborder Cicadae.

3. The use according to any one of claims 1 to 2, wherein the insect vector is the rabbit pentathorax.

4. The use according to any one of claims 1 or 2, wherein the insect vector is the corn yellow-winged leafhopper.

5. The use according to any one of claims 1 to 4, wherein the bacteria transmitted are selected from the group consisting of Candidatus phytopathogenic andricide and Phytoplasma solani.

6. Use according to any one of claims 1 to 4, wherein the transmitted bacteria are Spiroplasma species.

7. The use according to any one of claims 1 to 7, wherein methoprenaline is applied to a field without infected plants.

8. The use according to any one of claims 1 to 7, wherein methiprad is applied to a field comprising bacterially infected and non-infected plants.

9. Use according to any one of the preceding claims, wherein methoprenaline is applied to the foliage of the plant.

10. Use according to any one of the preceding claims, wherein methoprenaline is applied in an amount of 20 to 200 g per hectare.

11. Use according to any one of claims 1 to 3, 5 and 7 to 10, wherein the plants are selected from potatoes, sugar beets, and fodder beets.

12. Use according to any one of claims 1 to 2, 4 and 6 to 10, wherein the plants are selected from maize.

13. A method for protecting sugar beet plants from low sugar syndrome disease, the method comprising applying methoprene as defined in any one of claims 1 to 3, 5 and 7 to 10 to a field of uninfected plants.

14. A method for reducing or preventing the transmission of bacteria from insect vectors to plants, the method comprising the step of contacting the plants, parts thereof, propagation material thereof, the insects, their food supply, habitat or breeding ground as defined in any one of claims 1 to 12 with a pesticidally effective amount of methiprad or a stereoisomer, tautomer, salt or N-oxide thereof.

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