MXPA00002697A - Seed treatment fungicides for control of plant diseases - Google Patents

Abstract

A method for combatting plant fungi in a plant, which comprises applying to the seeds or tubers of the plant, an effective amount of a fungicidal composition comprising a fungicidally effective amount of a 2-alkoxyiminoacetamide compound, optionally in admixture with one or both of an alkylene bis-dithiocarbamate complex salt and a thiophanate compound. Fungicidal compositions comprising a fungicidally effective amount of a 2-alkoxyiminoacetamide compound, an alkylene bis-dithiocarbamate complex salt, and a thiophanate compound, are also described.

Description

FUNGICIDES OF TREATMENT OF SEEDS FOR THE CONTROL OF PLANT DISEASES RELATED REQUEST Reference is made and priority of the provisional application of E.U.A is claimed. with serial number 60 / 059,293, filed on September 18, 1997, entitled "SEED TREATMENT FUNGICIDES FOR CONTROL OF PLANT DISEASES "(" FUNGICIDES OF TREATMENT OF SEEDS FOR THE CONTROL OF PLANT DISEASES ").

FIELD OF THE INVENTION This invention relates to a method for controlling diseases caused by fungi in plants by applying to the seed or tuber a fungicidally effective amount of a 2-alkoxyiminoacetamide compound such as cymoxanil, optionally in admixture with one or more than one bis complex salt. -alkylene dithiocarbamate as mancozeb and a thiophanate compound as thiophanate-methyl. This invention also relates to a fungicidal composition comprising, in an added fungicidally effective amount, a 2-alkoxyiminoacetamide compound, a salt of alkylene bis-dithiocarbamate complex, and a thiophanate compound.

BACKGROUND OF THE INVENTION Late blight is a devastating disease that affected the Irish potato harvest 150 years ago. Now, however, the late blight fungus, Phitophthora infestans, is very different from its predecessors. New classes of P. infestans have evolved that are resistant to the fungicide and which are more aggressive with respect to pathogenicity in the potato tuber. As a result, disease can now be introduced into potato fields more efficiently than in the past through infected seed tubers.

It is the purpose of this invention to provide a novel method for combating plant fungi, particularly phytopathogenic fungi such as Phytophthora infestans. It is the purpose of this invention to provide a novel composition for combating plant fungi, particularly phytopathogenic fungi such as Phytophthora infestans.

BRIEF DESCRIPTION OF THE INVENTION This invention relates to a method for combating plant fungi in a plant, which consists of applying to the plant seeds or tubers a fungicidally effective amount of: a) a 2-alkoxyiminoacetamide compound of the formula: NC O O I II II? R- O-N = C-C-NH-C-NH-R1 wherein R is methyl or ethyl and R 1 hydrogen, alkyl or allyl of C 1 -C 4, preferably C 1 -C 4 alkyl, preferably methyl or ethyl; or b) the 2-alkoxyiminoacetamide compound in admixture with one or more compounds selected from the group consisting of: i) a salt of alkylene bis-dithiocarbamate complex of the formula: wherein R 4 and R 5 are each independently hydrogen or Ci-Cβ alkyl, preferably hydrogen or C 4 alkyl, preferably hydrogen, methyl or ethyl; Q is Zn, Fe, or Cu, preferably, Zn; and the ratio x to y is from about 3: 1 to about 100: 1, preferably, about 5: 1 to about 20: 1, preferably about 6: 1 to about 10: 1; Y I) a thiophanate compound of the formula: wherein R 2 and R 3 are each independently C 1 -C 6 alkyl, preferably C 1 -C 4 alkyl, preferably methyl or ethyl.

This invention also relates to a fungicidal composition consisting of: a) a 2-alkoxyiminoacetamide compound of the formula: NC O 0 R- 0 -N = C 1 -C "-NH-C II -NH-rR, wherein R is methyl or ethyl and R1 hydrogen, alkyl or allyl of CrC4, preferably CrC4 alkyl, preferably methyl or ethyl; b) an alkylene bis-dithiocarbamate complex salt of the formula: wherein R 4 and R 5 are each independently, hydrogen or C 1 -C 6 alkyl, preferably hydrogen or CrC 4 alkyl, preferably hydrogen, methyl or ethyl; Q is Zn, Fe, or Cu, preferably, Zn; and the ratio x to y is from about 3: 1 to about 100: 1, preferably about 5: 1 to about 20: 1, preferably about 6: 1 to about 10: 1; and c) a thiophanate compound d of the formula: wherein R2 and R3 are each independently alkyl CrC6, preferably C-? -C alkyl, preferably methyl or ethyl, in an effective aggregate amount.

DETAILED DESCRIPTION OF THE INVENTION The 2-alkoxyiminoacetamide compounds, complex alkylene bis-dithiocarbamate salts, and thiophanate compounds useful in the method and composition of this invention are known in the art, because they are methods of their preparation. See for example, the patents of E.U.A. Us. 3,957,847; 3,379,610 and 5,571, 443, respectively. The method and composition of this invention are particularly suitable for use against Phytophthora infestans or on potato plants and tubers. The composition of this invention and the compounds useful in the method of this invention can be formulated in conventional manner.

Examples of useful formulations include watered pastes, solid seed coatings, liquids, powders on the surface of the seed or tuber, solutions, suspensions, emulsions, indissoluble powders, emulsifiable concentrates, and the like. In general, the formulations consist of active ingredient from 1% to 99% by weight. In addition, the formulations may comprise extra additives such as surfactants, solid or liquid diluents, pigments, condensers, and the like. The method of application of the formulations to the seeds or tubers may vary depending for example on the compounds and / or formulation used. In general, the seed or tuber must be treated with 50 to 1200 ppm approximately, preferably between 300 to 900 ppm approximately, preferably approximately 700 ppm, for each 45.4 kg of seed or tuber, of the composition of this invention or of the compounds useful in the method of this invention. This invention preferably relates to a method for combating plant fungi in a plant, which comprises applying to the seeds or tubers of the plant, an effective amount of a fungicidal composition consisting of a fungicidally effective amount of: a) cymoxanil; or b) cymoxanil in combination with one or more of the group consisting of mancozeb and thiophanate-methyl.

This invention further relates to a fungicidal composition comprising cymoxanil, mancozeb and thiophanate-methyl, in an effective aggregate amount. Cimoxanil, mancozeb and thiophanate-methyl are all known compounds. Cimoxanil (foliar fungicide sold under the trademarks CURZATE and DPX-3217) is 2-cyano-N - [(ethylamino) carbonyl] -2- (methoxyimino) -acetamide. Mancozeb (a fungicide sold under the trademarks MANZATE-200 and DITHANE M-45) is a mixture of [[1, 2-ethanediylbis- (carbamodithioate)] (2-)] manganese and [[1,2-etanediylbis (carbamothioate )] (2) -] zinc. Thiophanate-methyl (a systematic fungicide sold under the trademarks TOPSIN M and NF-44) is [1, 2-phenylene-bis- (iminocarbono-thioyl) -bis- [carbamate] dimethyl. In the method of this invention wherein cymoxanil is mixed with thiophanate-methyl, generally satisfactory results can be obtained when the weight ratio of cymoxanyl: thiophanate-methyl is from about 1: 3 to 3: 1, preferably 1: 2 to 2. : 1, and preferably, 1: 1.5 to 1.5: 1. In the method of this invention wherein cymoxanil is mixed with mancozeb, in general, satisfactory results can be obtained when the weight ratio of cymoxanil: mancozeb is from about 1: 16 to 3: 1, preferably 1: 8 to 2: 1 , and preferably, 1: 3 to 1.5: 1. In the method of this invention wherein cymoxanyl, mencozeb and thiophanate-methyl are mixed, in general, satisfactory results can be obtained when the weight ratio of cymoxanil: mancozeb: thiophanate-methyl is from about 3: 1: 1 to about 1. : 16: 6, preferably, from 1.5: 1: 1 to approximately 1: 8: 3. Similarly, in the composition of this invention, satisfactory results can generally be obtained when the weight ratio of cymoxanil: mancozeb: thiophanate-methyl is about3: 1: 1 to about 1: 16: 6, preferably, from 1.5: 1: 1 to about 1: 8: 3. The formulations may consist of from 0 to about 20% of an agriculturally acceptable surfactant such as dispersing agents and humectants, for example, the condensation product of formaldehyde with naphthalenesulfonate, an alkylarylsulfonate, a ligninsulfonate, a fatty sulfate, an alkylphenol ethoxylated and an ethoxylated fatty alcohol. In addition, the formulations may comprise from about 10 to 99% of a solid or liquid diluent accepted in agriculture, including vehicles, such as talc, zeolites, Alder's bark, kaolin, diatomaceous earth, mineral oil, water and the like. The following examples are provided for illustrating the present invention.

EXAMPLES EXAMPLE 1 (A) An inert potato powder system (PDIS) was prepared by mixing the following 3 inert diluents in a tape mixer: talc (Cyprus BT-200) (48.39% w / w), zeolite (16.12% w / w) ), and Alder bark (35.49% w / w). The powders mentioned below in Table 1 were prepared by mixing PDIS and the compounds at the indicated concentrations in a ribbon blender and evaluated in activity against P. infestans at the indicated active ingredient application regimen.

TABLE 1 1 parts per million per 45.4 kg of seed (tuber) 2 thiophanate-methyl 3 (E, Z) 4- [3- (4-chlorophenyl) -3- (3,4-dimethoxyphenyl) acryloyljmorpholine 4 Propyl [3- (dimethylamino ) propyl) carbamate (b) The in vitro sieving procedure was carried out as follows: The potato tubers were removed from storage at 5 ° C and could be at room temperature. They were washed with tap water and sterilized in 5% commercial bleach (Clorox) for 10 minutes. They were rinsed in sterile distilled water and dried. Phytophthora infestans grew on plates with agar at 18 ° C for 10-14 days. 20 ml of sterile distilled water at 5 ° was added to each plate. The agar was shaken or cut into small sections and placed at 10-12 ° C, for two hours to release the zoospores. The tubers were cut into slices of uniform size (1 cm thick). Each powder was applied to 20 slices in 0.227 gr / 45.4 kg. Two sets of 20 potato slices were not treated with powder and were used as controls. Each slice of powdered potato was placed on a moistened, sterile filter paper in a Petri dish. The amount of zoospore suspension at a concentration of 20,000 spores / ml was determined. 100 ml of this spore suspension was applied to a filter paper disk. Each treated disc was placed in the center of each potato slice. A series of 20 slices of powder-free potato were not inoculated and used as a sterile control. Each potato slice was placed in the dark at 18 ° C for 7 days. After 7 days, the disease status of each potato slice was evaluated. Next in Table 2, the growth and sporulation of P.infestans is evaluated for each potato slice on a scale of plus (+) or minus (-). The minus sign indicates no growth of P. Infestans while the plus sign indicates growth. Growth was measured as minimum (+), good (++), or good and sporulation (+++).

TABLE 2 Growth and sporulation of P. infestans EXAMPLE 2 (A) The powders were prepared as described above in Example 1. (B) The in-vivo sieving procedure was carried out as follows: Potato tubers were removed from storage at 5 ° C and could be at temperature ambient. They were washed with tap water and sterilized in 5% commercial bleach (Clorox) for 10 minutes. They were rinsed in sterile distilled water and dried. Phytophthora infestans grew on plates with agar at 18 ° C during -14 days. 20 ml of sterile distilled water at 5 ° C was added to each plate.

The agar was shaken or cut into small sections and placed at 10-12 ° C for 2 hours to release the zoospores. The amount of zoospore suspension at a concentration of 20 was determined, 000 spores / ml. Small perforations were made in the tubers with a sterile needle and the perforated tubers were immersed in the suspension of zoospores P. Infestans. The tubers were incubated at 15 ° C with 95% relative humidity for 7-10 days. After incubation the tubers were cut into pieces of 56.7-113.4 gr. Each powder was applied to 15 pieces at 0.227 / 45.4 kg or according to the manufacturer's instructions. A series of 15 pieces was not treated and was used as a control.

The potatoes not submerged in the zoospores were also cut into pieces of 56.7-113.4 gr and a series of 15 pieces of non-inoculated potatoes were used as a sterile control. The pieces of potatoes were placed in a sandy soil and covered at 17 ° C in the day and 13 ° C in the night for 32 days. Growth after the emergency was monitored for 14-28 days. Disease symptoms were evaluated visually. A stem / leaf tissue was tested for the detection of P. infestans by appropriate means. Finally the pieces of potato seed were removed and cut in half and the presence of disease was evaluated visually. The results of this test are presented below in Tables 3 and 4.

TABLE 3 TABLE 4 Tuber and stem health 1 Tuber tuber; No emergency 2 Tuber with blight; Infected stems of small size 3 Tuber with blight; Infected stems of average size 4 Clean tubers; Healthy stems without infecting EXAMPLE 3 The following new powders in Table 5 were prepared as described in Example 1.

TABLE 5 These powders were tested using the procedure described above in example 2. The results of this test are shown below in table 6.

TABLE 6 Tuber and stem health and emergency EXAMPLE 4 The following powders in table 7 were prepared as described in example 1.

TABLE 7 These powders (as well as powders number 7 and 8) were tested using the procedure described above in Example 2 using Russet Burbank tubers. The results of this test (10 replicates / treatment) are shown below in table 8.

TABLE 8 Emergency and stem health EXAMPLE 5 The powders prepared above in example 4 (as well as powders number 7 and 8) were tested using the procedure described above in example 2 using Red Nordland tubers. The results of this test (7 replicates / treatment) are shown below in the table 9.

TABLE 9 Tuber and stem health and emergency EXAMPLE 6 The tubers of Shepody potato were contaminated / inoculated with Phytophthora infestans and put apart ("source tubers"). After two weeks, one (1) source tuber was cut in quarters through the diseased area with a cutting knife. Without cleaning or changing the knife, then five (5) tubers of Shepody potato without inoculation were cut in quarters. This procedure (1 source tuber / 5 uninfected tubers) was repeated to provide sufficient tubers for 30 replicates per treatment (Table 10 below). The cut tubers were weighed (source and without inoculation) and the appropriate amount of each powder mentioned in Table 10 was applied to the tubers by placing the tubers in a double-dust paper bag and then shaking the bag. The treated tubers were then placed in an unsealed plastic bag (one bag per treatment) and incubated at 10 ° C, 80-90% RH for two weeks. After two (2) weeks, the tubers placed in the bags were extracted from the environment of 10 ° C, 80-90% RH. Then the bags were rolled up or shaken to simulate movement from the storage area to the planting area. The tubers were extracted and the propagation of P. infestans -% of infected tubers was determined. The tubers were placed at room temperature and planted. The source tubers were not planted. Emergency and infection data were obtained as described above in example 2 (30 replicates / treatment). The results of this test are shown below in table 10.

TABLE 10 Emergency v Stem tuber health EXAMPLE 7 The procedure described above in Example 6 was repeated using Red Nordland potato tubers. The results of this test are presented below in table 11.

TABLE 11 Tuber and stem health and emergency The results in Tables 10 and 11 show that tubers contaminated with P infestans propagated from a source of contaminated seed through cutting and handling of the tubers prior to treatment and planting still produced plants that were disease free when treated. tubers in accordance with the present invention before planting.

Claims (18)

NOVELTY OF THE INVENTION CLAIMS

1. A method for combating fungi in a plant, which consists of applying to the seeds or tubers of the plant an effective amount of a fungicidal composition consisting of a fungicidally effective amount of: a) a 2-alkoxyiminoacetamide compound of the formula:

NC O O R- O- N = C I -C II - NH- C II - NH- r RV1l wherein R is methyl or ethyl and R 1 is hydrogen, C 4 alkyl or allyl; or b) the 2-alkoxyiminoacetamide compound in combination with one or more compounds selected from the group consisting of: i) an alkylene bis-dithiocarbamate complex salt of the formula: wherein R 4 and R 5 are each independently hydrogen or C 1 -C 6 alkyl; Q is Zn, Fe, or Cu; and the ratio of x to y is from about 3: 1 to about 100: 1; and ii) a thiophanate compound of the formula: wherein R 2 and R 3 are each independently, CrC 6 alkyl. 2. The method according to claim 1 further characterized in that R and R2, and R3 are each independently, C C alkyl, and R4 and R5 with each independently, hydrogen or C C alkyl.

3. The method according to claim 2, further characterized in that R1, R2 and R3 are each independently methyl or ethyl, and R4 and R5 are each independently hydrogen, methyl or ethyl.

4. The method according to claim 3, further characterized in that Q is Zn and the ratio of x to y is from about 5: 1 to about 20: 1.

5. The method according to claim 4, further characterized in that the ratio of x to y is from about 6: 1 to about 10: 1.

6. The method according to claim 5, further characterized in that the alkoxyiminoacetamide compound is cymoxanil; the compound of the alkylene bis-dithiocarbamate complex salt is mancozeb; and the thiophanate compound is thiophanate-methyl.

7. - The method according to claim 1, further characterized because the plant is a potato plant.

8. - The method according to claim 7, further characterized because the fungus is late blight, Phytophthora infestans

9. - A fungicidal composition consisting of an amount fungicidally effective of: a) a 2-alkoxyiminoacetamide compound of the formula:

NC O O

I II II, R- 0-N = C-C-NH-C-NH-R1 wherein R is methyl or ethyl and R 1 hydrogen, alkyl or allyl of CrC 4; b) an alkylene bis-dithiocarbamate complex salt compound of the formula: wherein R4 and R5 are each independently hydrogen or alkyl of Ci-Cß; Q is Zn, Fe, or Cu; and the ratio of x to y is approximately 3: 1 at approximately 100: 1; and c) a thiophanate compound of the formula: wherein R 2 and R 3 are each independently, CrC 6 alkyl. 10. The composition according to claim 9 further characterized in that R1 and R2, and R3 are each independently, CrC4 alkyl, and R4 and R5 are each independently, hydrogen or dC4 alkyl. 11. The composition according to claim 10, further characterized in that R1, R2 and R3 are each independently methyl or ethyl, and R4 and R5 are each independently hydrogen, methyl or ethyl.

12. The composition according to claim 11, further characterized in that Q is Zn and the ratio of x to y is from about 5: 1 to about 20: 1.

13. The composition according to claim 12, further characterized in that the ratio of x to y is from about 6: 1 to about 10: 1.

14. The composition according to claim 13, further characterized in that the 2-alkoxyiminoacetamide compound is cymoxanyl; the compound of the alkylene bis-dithiocarbamate complex salt is mancozeb; and the thiophanate compound is thiophanate-methyl.

15. - A method for combating plant fungi in a plant, which consists of applying to the seeds or tubers of the plant, an effective amount of a fungicidal composition consisting of a fungicidally effective amount of: a) cymoxanil; b) cymoxanil in combination with mancozeb or thiophanate-methyl; or c) cymoxanil in combination with mancozeb and thiophanate-methyl.

16. The method according to claim 15, further characterized in that the plant is a potato plant.

17. The method according to claim 16, further characterized in that the fungus is Late Blight, Phytophthora infestans.

18. A fungicidal composition consisting of cymoxanil, mancozeb and thiophanate-methyl, in an aggregate effective amount.