HERBICIDAL MIXTURES COMPRISING L-GLUFOSINATE OR ITS SALT AND AT LEAST ONE VLCFA INHIBITOR

Abstract

The present invention relates to herbicidal mixture comprising L-glufosinate or its salt and at least one VLCFA inhibitor. The invention furthermore relates to a method for controlling undesirable vegetation in burndown programs, in industrial vegetation management and forestry, in vegetable and perennial crops and in turf and lawn.

Claims

1.-15. (canceled)

16. A herbicidal mixture comprising a) L-glufosinate and its salts as compound I; and b) S-metolachlor as compound II; wherein L-glufosinate comprises more than 70% by weight of the L-enantiomer.

17. The herbicidal mixture of claim 16, wherein compound I is selected from the group consisting of L-glufosinate-ammonium, L-glufosinate-sodium as L-glufosinate salts, and L-glufosinate as free acid.

18. The herbicidal mixture of claim 16, wherein compound I is L-glufosinate-ammonium.

19. The herbicidal mixture of claim 16, wherein L-glufosinate comprises more than 80% by weight of the L-enantiomer.

20. The herbicidal mixture of claim 16, wherein L-glufosinate comprises more than 90% by weight of the L-enantiomer.

21. The herbicidal mixture of claim 16, wherein L-glufosinate comprises 95% by weight of the L-enantiomer.

22. The herbicidal mixture of claim 16, wherein the weight ratio of compound I to compound II is from 1000:1 to 1:500.

23. The herbicidal mixture of claim 16, wherein the weight ratio of compound I to compound II is from 50:1 to 1:5.

24. A pesticidal composition, comprising a liquid or solid carrier and the herbicidal mixture of claim 16.

25. A method for controlling undesirable vegetation, which method comprises applying the herbicidal mixture of claim 16 to a locus where undesirable vegetation is present or is expected to be present.

26. The method as claimed in claim 25, comprising application of the herbicidal mixture prior to emergence of the crop.

27. The method as claimed in claim 25, comprising application of the herbicidal mixture prior to planting the crop.

28. The method of claim 25, wherein the crop is selected from rice, maize, pulse crops, cotton, canola, small grain cereals, soybeans, peanut, sugarcane, sunflower, plantation crops, tree crops, nuts and grapes.

29. The method of claim 25, wherein the crop is selected from glufosinate tolerant crops.

30. The method of claim 25, wherein the crop is soybeans.

31. The method of claim 25, wherein compounds I and II of the herbicidal mixture are applied simultaneously, that is jointly or separately, or in succession.

Description

BIOLOGICAL EXAMPLES

[0155] Synergism can be described as an interaction where the combined effect of two or more compounds is greater than the sum of the individual effects of each of the compounds. The presence of a synergistic effect in terms of percent control, between two mixing partners (X and Y) can be calculated using the Colby equation (Colby, S. R., 1967, Calculating Synergistic and Antagonistic Responses in Herbicide Combinations, Weeds, 15, 21-22):

[00001]$E=X+Y-\frac{\mathrm{XY}}{100}$

[0156] When the observed combined control effect is greater than the expected (calculated) combined control effect (E), then the combined effect is synergistic.

[0157] The following tests demonstrate the control efficacy of compounds, mixtures or compositions of this invention on specific weeds. However, the weed control afforded by the compounds, mixtures or compositions is not limited to these species. The analysis of synergism or antagonism between the mixtures or compositions was determined using Colby's equation.

Test Method:

[0158] The culture containers used were plastic flowerpots containing loamy sand with approximately 3.0% of humus as the substrate. The seeds of the test plants were sown separately for each species and/or resistant biotype. For the pre-emergence treatment, the active ingredients, which had been suspended or emulsified in water, were applied directly after sowing by means of finely distributing nozzles. The containers were irrigated gently to promote germination and growth and subsequently covered with transparent plastic hoods until the plants had rooted. This cover caused uniform germination of the test plants, unless this had been impaired by the active ingredients. For the post-emergence treatment, the test plants were first grown to a height of 3 to 15 cm, depending on the plant habit, and only then treated with the active ingredients which had been suspended or emulsified in water. For this purpose, the test plants were either sown directly and grown in the same containers, or they were first grown separately as seedlings and transplanted into the test containers a few days prior to treatment. Depending on the species, the plants were kept at 10-25° C. or 20-35° C., respectively. The test period extended to 20 days after treatment. During this time, the plants were tended, and their response to the individual treatments was evaluated. The evaluation was carried out by using a scale from 0 to 100. 100 means no emergence of the plants or complete destruction of at least the above-ground parts, and 0 means no damage, or normal course of growth. Data shown are the mean of two replications.

[0159] Products:

[0160] L-Glufosinate: 5% EC formulation

[0161] Pyroxasulfone: 85% WG formulation

[0162] Pethoxamid: 5% EC formulation

Weeds in the Study:

[0163]

TABLE-US-00003 EPPO Code Scientific Name ABUTH Abutilon theophrasti AVE FA Avena fatua

Example 1: Post Emergence Treatment with the Mixture of L-Glufosinate with Pyroxasulfone

[0164]

TABLE-US-00004 Herbicidal activity against Application rate in g ai/ha ABUTH L-Glufosinate Pyroxasulfone Found Calculated 200 — 65 — — 50 70 — 200 50 100 90 200 — 65 — — 25 40 — 200 25 100 79

Example 2: Post Emergence Treatment with the Mixture of L-Glufosinate with Pethoxamid

[0165]

TABLE-US-00005 Application rate in g ai/ha Herbicidal activity against ABUTH AVEFA L-Glufosinate Pethoxamid Found Calculated Found Calculated 150 — 55 —  0 — — 100  0 —  0 — 150 100 98 55 40 0  75 —  0 —  0 — —  50  0 —  0 —  75  50 35  0  5 0