Mixtures of sabadilla alkaloids and <i>Bacillus thuringiensis </i>and uses thereof

Abstract

The present invention is directed to pesticidal mixtures comprising sabadilla alkaloids and Bacillus thuringiensis and methods of controlling pests including insects and mites by application of pesticidal mixtures comprising sabadilla alkaloids and Bacillus thuringiensis.

Claims

1. A pesticidal mixture comprising an effective amount of sabadilla alkaloids and Bacillus thuringiensis kurstaki, wherein the ratio of sabadilla alkaloids to Bacillus thuringiensis kurstaki is from about 2:1 to about 1:200.

2. The mixture of claim 1, wherein the sabadilla alkaloids are derived from Schoenocaulon officinale.

3. The mixture of claim 1, wherein the sabadilla alkaloids are veratridine and cevadine.

4. The mixture of claim 1 further comprising one or more excipients selected from the group consisting of solvents, anti-caking agents, stabilizers, defoamers, slip agents, humectants, dispersants, wetting agents, thickening agents, emulsifiers, penetrants, adjuvants, synergists, polymers, propellants and/or preservatives.

Description

DETAILED DESCRIPTION OF THE INVENTION

(1) Applicant unexpectedly discovered that pesticidal mixtures of sabdilla alkaloids and Bacillus thuringiensis provided enhanced pesticidal activity compared to either pesticide alone. Specifically, this combination results in a reduced rate of resistance development. Further, Applicant discovered that pesticidal mixtures of sabadilla alkaloids and Bacillus thuringiensis were capable of controlling a large variety of arthropods.

(2) The present invention is directed to pesticidal mixtures comprising an effective amount of sabadilla alkaloids and B. thuringiensis.

(3) Sabadilla alkaloids may be derived from any species of Schoenocaulon. The genus Schoenocaulon includes the following species: S. calcicola, S. caricifolium, S. comatum, S. conzattii, S. dubium (alt. S. gracile), S. framei, S. ghiesbreghtii (alt. S. drummondii, S. yucatanense), S. ignigenum, S. intermedium, S. jaliscense, S. macrocarpum (alt. S. lauricola), S. madidorum, S. megarrhizum, S. mortonii, S. oaxacense, S. obtusum, S. officinale, S. pellucidum, S. plumosum, S. pringlei, S. rzedowskii, S. tenorioi, S. tenue, S. tenuifolium, S. texanum, and S. tigrense. In a preferred embodiment the Schoenocaulon sp. alkaloids are derived from S. officinale. In another preferred embodiment the Schoenocaulon sp. alkaloids are veratridine and cevadine.

(4) B. thuringiensis includes many subspecies, each of which are suitable for use in the present invention alone, or in combination. Subspecies of B. thuringiensis include, but are not limited to, aizawai, alesti, berliner, βnitimus, cameroun, canadiensis, colmeri, coreanensis, dakota, darmstadiensis, dendrolimus, entomocidus, fukuokaensis, galleriae, higo, indiana, israelensis, japonensis, japonensis Buibui, jegathesan, kenyae, kumamotoensis, kunthala, kurstaki, kyushuensis, Medellin, mexcanensis, morrisoni, neoleonensis, nigeriae, oloke, ongbei, ostriniae, pakistani, pondicheriensis, roskildiensis, san diego, shandogiensis, shanghai, silo, sotto, subtoxicus, tenebrionis, thompsoni, thuringiensis, tochigiensis, tohokuensis, tolworthi, toumanoffi, wuhanensis, yunnanensis. In a preferred embodiment, B. thuringiensis comprises bacteria of subspecies selected from aizawai, israelensis, kurstaki, thuringiensis and combinations thereof. In a more preferred embodiment, B. thuringiensis comprises bacteria of subspecies selected from aizawai, kurstaki, thuringiensis and combinations thereof. In another preferred embodiment, B. thuringiensis comprises bacteria from a combination of subspecies selected from the group consisting of: aizawai and kurstaki; aizawai and thuringiensis; and kurstaki and thuringiensis.

(5) As used herein, all numerical values relating to amounts, weight percentages and the like are defined as “about” or “approximately” each particular value, namely, plus or minus 10%. For example, the phrase “at least 5% by weight” is to be understood as “at least 4.5% to 5.5% by weight.” Therefore, amounts within 10% of the claimed values are encompassed by the scope of the claims.

(6) The term “effective amount” means the amount of the formulation that will control the target pest. The “effective amount” will vary depending on the mixture concentration, the type of pest(s) being treated, the severity of the pest infestation, the result desired, and the life stage of the pest during treatment, among other factors. Thus, it is not always possible to specify an exact “effective amount.” However, an appropriate “effective amount” in any individual case may be determined by one of ordinary skill in the art.

(7) In a preferred embodiment, the ratio of sabadilla alkaloids to B. thuringiensis is from about 2:1 to about 1:200, preferably from about 1:1 to about 1:100.

(8) In another preferred embodiment, the pesticidal mixtures of the present invention may contain one or more excipients selected from the group consisting of solvents, anti-caking agents, stabilizers, defoamers, slip agents, humectants, dispersants, wetting agents, thickening agents, emulsifiers, penetrants, adjuvants, synergists, polymers, propellants and/or preservatives.

(9) The present invention is further directed to methods of controlling a pest comprising applying a pesticidal mixture comprising an effective amount of sabadilla alkaloids and B. thuringiensis to the pest or the pest's environment.

(10) In a preferred embodiment, the pest is selected from an insect and a mite.

(11) In an embodiment, the pest controlled is selected from the group consisting of aphids (Homoptera), whiteflies (Hemiptera), thrips (Thysanoptera), bed bugs (Hemiptera), fleas (Siphonaptera), caterpillars/worms (Lepidoptera), beetles (Coleoptera), cockroaches (Blattodea), flies (Diptera), ants (Hymenoptera), mosquitoes (Culicidae) and mites (Acari). In a preferred embodiment, the pest controlled are selected from the group consisting of common bed bugs (Cimex lectularius), green peach aphids (Myzus persicae), house fly (Musca domestica), yellow fever mosquito (Aedes aegypti), southern house mosquito (Culex quinquefasciatus), African malaria mosquito (Anopheles gambiae), common malaria mosquito (Anopheles quadrimaculatus) and German cockroach (Blattella germanica).

(12) The pesticidal mixtures of the present invention can be applied by any convenient means. Those skilled in the art are familiar with the modes of application including spraying, brushing, soaking, in-furrow treatments, granules, pressurized liquids (aerosols), fogging or side-dressing.

(13) In a preferred embodiment, sabadilla alkaloids are applied to the pest or the pest's environment at a rate from about 1 to about 1,000 grams per hectare (“g/HA”), preferably from about 10 to about 700 g/HA and most preferably from about 22 to about 560 g/HA.

(14) In a preferred embodiment, B. thuringiensis is applied to the pest or the pest's environment at a rate from about 1 to about 5,000 g/HA, more preferably from about 100 to about 3,000 g/HA and most preferably from about 560 to about 2,242 g/HA.

(15) As used herein, “control” a pest or “controlling” pest(s) refers to killing, incapacitating, repelling, or otherwise decreasing the negative impact of the pest on plants or animals to a level that is desirable to the grower or animal.

(16) As used herein, “pest's environment” refers to any area that the pest is present during any life stage. One environment likely to be treated by the methods of the present invention includes the plants that the pest is living on and the surrounding soil. The pest's environment may also include harvested plants, gardens, fields, greenhouses, or other buildings, and various indoor surfaces and structures, such as furniture including beds, and furnishings including books, clothing, etc.

(17) The articles “a,” “an” and “the” are intended to include the plural as well as the singular, unless the context clearly indicates otherwise. For example, the methods of the present invention are directed to controlling “pest” but this can include control of a multiple pests (such as a more than one insect or more than one insect species or more than one mite or more than one mite species).

(18) The following examples are intended to illustrate the present invention and to teach one of ordinary skill in the art how to use the extracts of the invention. They are not intended to be limiting in any way.

EXAMPLES

(19) Dipel® was used as the source of B. thuringiensis subspecies kurstaki (“Btk”).

(20) Xentari® was used as the source of B. thuringiensis subspecies aiwazai (“Bta”).

(21) Novodor was used as the source of B. thuringiensis subspecies thuringiensis (“Btt”).

Example 1—Control of Caterpillars/worms (Lepidoptera) with B. thuringiensis Subspecies aiwazai

(22) In this study, the response of caterpillars/worms (Lepidoptera) to application of a 1:25, 1:1, 1:100 and 1:4 ratio of sabadilla (S. officinale)alkaloids to Bta will be observed. Specifically, sabadilla alkaloids and Bta will be applied to the pest at the respective rates of: 1) 22 g/HA and 560 g/HA; 2) 560 g/HA and 560 g/HA; 3) 22 g/HA and 2242 g/HA; and 4) 560 g/HA and 2242 g/HA.

(23) The results of the study are predicted to show enhanced activity including reduced rates of resistance.

Example 2—Control of Caterpillars/Worms (Lepidoptera) with B. thuringiensis Subspecies kurstaki

(24) In this study, the response of caterpillars/worms (Lepidoptera) to application of a 1:25, 1:1, 1:100 and 1:4 ratio of sabadilla (S. officinale)alkaloids to Bta will be observed. Specifically, sabadilla alkaloids and Bta will be applied to the pest at the respective rates of: 1) 22 g/HA and 560 g/HA; 2) 560 g/HA and 560 g/HA; 3) 22 g/HA and 2242 g/HA; and 4) 560 g/HA and 2242 g/HA.

(25) The results of the study are predicted to show enhanced activity including reduced rates of resistance.

Example 3—Control of Caterpillars/Worms (Lepidoptera) with B. thuringiensis Subspecies thuringiensis

(26) In this study, the response of caterpillars/worms (Lepidoptera) to application of a 1:25, 1:1, 1:100 and 1:4 ratio of sabadilla (S. officinale)alkaloids to Bta will be observed. Specifically, sabadilla alkaloids and Bta will be applied to the pest at the respective rates of: 1) 22 g/HA and 560 g/HA; 2) 560 g/HA and 560 g/HA; 3) 22 g/HA and 2242 g/HA; and 4) 560 g/HA and 2242 g/HA.

(27) The results of the study are predicted to show enhanced activity including reduced rates of resistance.