FR2482829A1 - MEANS OF KILLING LIMACES - Google Patents

Abstract

THE PRESENT INVENTION RELATES TO A MEANS FOR COMBATING TERRESTRIAL MOLLUSCS. IT IS CHARACTERIZED IN THAT THIS MEANS INCLUDES AN ABSORBENT SUBSTRATE, ONE SIDE OF WHICH IS WATERPROOF AND THE OTHER COVERED WITH A MOLLUSQUICIDAL COMPOSITION. THE INVENTION APPLIES TO THE DESTRUCTION OF SLUGS.

Description

MEANS OF KILLING LIMACES

  The present invention relates to means for killing slugs, and

  particularly absorbent substrates coated with mullusquicidal compositions.

  Molluscs, especially slugs such as Agriotimax reticuiatus, are devourers of plant substances and cause considerable damage in gardens and fences.

  British Patent No. 991939 discloses a method for combating eschar-

  of the genera Gncomeliana, AustraZcrbis, BuZinus and Lymnaea, by means of

  diphenyl methylamine derivatives and compositions containing these products.

  These derivatives are to be used mainly in the snail aquatic habitat areas, but it is indicated inter alia that an absorbent support such as a porous tile, clay granules or a material

  fibrous like paper or cloth, can be impregnated with derivatives.

  The Applicant has found that an absorbent substrate which is impermeable

  on one side, constitutes an attractive residential area for

  terrestrial lusques when placed on the ground, the impermeable surface

  the water being at the top, and that when such a substrate bears on its non

  waterproof a layer of mollusquicidal composition and that this face is deposited against the ground, there is a very effective way to fight

terrestrial molluscs.

  Accordingly, the present invention provides means for controlling terrestrial molluscs, in particular slugs, comprising an absorbent substrate which is impervious on one side, and the other side of which

  is coated with a mullusquicidal composition.

  The absorbent substrate may be rigid, for example cardboard or a porous ceramic tile or a hollow disc of similar material, the

  concave face thereof being coated with molluscicidal composition.

  In general, the soil on which the tile or disc is placed is sufficiently

  irregularly so that slugs can penetrate between the surface

  from the ground and the lower surface of the tile or disc.

  However, the edge of the disc can be slotted to facilitate access of the slugs to the lower part of this risk and, similarly, the tile can be provided with protrusions arranged on the side coated with molluscicide

  to keep it at a distance from the ground.

  In a variant, the substrate may be flexible such as a fabric, a plastic foam or in particular a sheet of paper. Paper of any color or size may be used, although green is preferred for aesthetic reasons. The leaf can be designed to be placed under vegetables or fruit, for example squash and strawberries, in the field or garden, where the vegetable or fruit is placed on the water-impermeable upper surface. The waterproof surface protects the substrate and the molluscan coating from the rain and, moreover,

  it helps maintain some moisture between the underside of the sub-

  strat and the soil on which it is disposed, especially when it is also relatively impervious to water vapor. Slugs clump under the substrate where moisture is high and they are poisoned by eating the

  surface coated with mollusquicide and by contact of their foot with it.

  In the case of distinct plants, the substrate such as for example paper or ceramic, may have the form of disks that are placed under the plant. It is convenient that this disc has a diameter of about 20 to 30 cm; a central portion about 3 to 5 cm in diameter is removed and a slot is made, for example a radial slot, connecting the circumference with the resulting hole so that the disc can easily be put into position.

  place around the stem of the plant.

  The waterproof coated paper can also be placed under

  form of a roll that can be unwound and used to provide a bar-

  continue along a row in a kitchen garden or

  In practice, stones or earth are placed on the paper tape to prevent it from being blown by the wind. Waterproof paper

  the water known as "Labcoat" or "Benchcote" is suitable for

  particularly in the context of the invention. It is an absorbent paper

  reinforced with a thin film of polythene, which is not only

  not only water-soluble but also relatively impervious to water vapor.

  Mollusquicides which may be used in the

  lusquicides are for example: metaldehyde, copper salts, 4 (methylthio) -

  3,5-xylyl methylcarbamate, 1-N-methylcarbamate, S2-cyanoethyl-N - [(methyl)

  carbamoyl) oxyl-thioacetamnidate and nicotinanilide. Suitable copper molluscicides are inorganic copper salts, such as, for example, copper sulfate, and organic salts such as, for example, dimethyl

copper dithiocarbamate.

  The application rate of molluscq icide on the surface of the porous substrate

  obviously depends on the effectiveness of the particular -ollusquicide implemented.

  In the case of metaldehyde, an application rate of between 30 and 40 g / m2 of substrate is generally satisfactory, but simple tests will easily show the optimum proportion of metaldehyde or other molluscicides.

  to be used in the particular compositions and in the specific case envisaged.

  The mollusquicide is applied to the surface of the substrate in the form of a composition comprising a solid binder such as gelatin, starch, gums or resins of synthetic or natural origin, for example

  carbomethoxy methyl cellulose and gum tragacanth, or clay.

  Among these products, it is preferred to use gelatin; indeed, in the coating of mollusquicidal composition, it plays not only the role of binder

  but also absorbs water when the substrate is deposited on the ground.

  When the substrate is paper, the water-swollen gelatin weighs it down

  and keep it on the ground. The attractiveness of the coated substrate may also

  to be increased by incorporation into the molluscan composition of an attractant element for slugs such as a flourous substance such as bran and

  vitamin B, which are perfectly suitable for this purpose.

  It is better to apply on paper, about 750 to 1250g of

  molluscicidal solution per square meter.

  A suitable thickness of the coating deposited on the substrate is between 0.5 and 1.5 mm. Since molluscs attracted to the coated substrate crawl on the underside coated with molluscicide, the Applicant has also found that the effectiveness of the coated substrate can be improved by incorporating into the molluscanic coating of an activator

  which will favor the taking of mollusquicide through the foot of the mollusc.

  The mollusquicide, and optionally the activator, may be in the molluscicidal composition in any suitable proportion, the

  value thereof and the appropriate rate of application of the

  are determined by simple tests. For example, in the case of metaldehyde, a proportion of about 3 to 4% by weight of the composition

  is suitable, depending on the weight of the coating applied. When an activity

  is achieved, a satisfactory rate of destruction is obtained, even by reducing the proportion of mollusquicide by 25 to 50%, for example

  using 2.0 to 2.5% metaldehyde, applied at a rate of 20 to 25 g / m2.

  Activators useful for the composition according to the invention are enzymes and proteins that can stimulate endocytosis or pinocytosis

  in the epithelial cells of the mollusc's foot.

  Suitable activators are substances which induce pinocytosis in Amoeba (amoeba), cf. for example the article by C. Chapman-Andresen in Compte.rend Lab.CarLsberg 33, p. 73/264 (1962). A test for pinocytosis is described by w. Strauss in J. Biophysic and Biochem. Cytol.5, No. 2, 193 (1959) and this assay can be used to identify enzymes and proteins.

  suitable teens as activators in the context of the invention.

  Suitable activators include ribonuclease, blood albumin, bovine serum albumin, horseradish peroxidase, egg albumin and

  the enzyme PFC (enzymatic residue from A.B.M. Chemicals).

  The proportion of enzyme or protein activator can be understood

  between 0.5 and 10% by weight of the composition.

  Alternatively, the effectiveness of molluscicide can be improved

  by incorporating into the composition, as an activator, a surfactant

  active. Suitable agents in this respect are, for example, non-proprietary agents.

  ionic agents such as condensation products of a polyalkylene oxide and alkylphenols and polyoxyalkylene fatty acid esters, cationic agents such as quaternary ammonium salts, for example cetyltrimethylammonium chloride, cetylpyridinium and anionic agents such as sodium salts of long-chain secondary alkyl sulfates, for example sodium lauryl sulfate, alkyl aryl sulphate salts, sodium deoxycholate, sodium taurocholate and

sodium tauroglycocholate (TGC).

  Suitable proportions of surfactant in the composition

  are between 0.1 and 1% by weight depending on the type of agent.

  In the case of sodium tauroglycocholate and sodium lauryl sulphate,

  it is convenient to use 0.2 to 0.4% by weight of agent.

  In the case of sodium acetate, 1.5 to 3% by weight of the composition

  constitute a very advantageous proportion.

  Sodium acetate can also be used to induce a rise through the membranes in the cells of the mollusk and for this reason

  uses a proportion of about 1 to 5% by weight of the composition.

  The absorbent substrate can also be made waterproof

  in a suitable manner by applying to it any kind of

  it is able to repel water, but which in itself does not also repel slugs, as for example by its smell. Suitable impervious substances are, for example, wax, silicones

and synthetic polymers.

  In a variant, the substrate can be made impermeable to water in it

  adjoining a thin film of polymer such as polythene, poly-

  ester or p.v.c. which also greatly reduces the passage of steam

of water through the substrate.

  In another variant, valid in the case of a substrate consisting of a tile or a porous ceramic disk or the like, the surface to be

  placed above when in use can be varnished.

  Other advantages and features of the present invention are

  will read the following description and examples given in

  illustrative but non-limiting title.

EXAMPLE 1

  An activated molluscicide "A" composition is prepared as follows:

  26 g of brine are mixed with 100 ml of water and homogenized to a coarse paste.

  38 g of gelatin are introduced to the homogenized bran and heated while stirring to form a thick paste. The paste is allowed to cool and 4% of metaldehyde and 2% of bovine serum albumin are added with stirring while the gel is still viscous. The viscous gel mixture is then

  brush or roller) on the absorbent surface of the waterproof paper.

  water-equilibrated (eg "Labcoat" or "Benchcote") and allowed to cool

again and dried.

  A similar "B" composition is prepared but omitting the 2% of

  bumble and apply it to waterproof paper in the same way.

  The procedure is repeated with a composition "C" which is devoid of both

of albumin and metaldehyde.

  "Labcoat" or "Benchcote" paper sheets thus treated, measuring approximately 15 x 15 cm are deposited in a field. The control leaves and the

  test sheets are spread side by side. The results obtained in one

  7-day period are illustrated in the following Table I:

TABLE I

  A- Paper containing sound / gel, metaldehyde and albumin.

  B. Paper containing sound / gel and metaldehyde only.

  C. Paper containing sound / gel only.

A B C

  DAY 1 Sliced slugs .................. 32 13 O 2 .................. 17 il11 O

3 ".................. 11 4 O

4 .................. 9 2 O

5 .................. 6 1 0

6 ".................. 4 2 O

7 ".................. 4 1 O

  These results show that, in fact, "A" and "B" type slug papers are effective in the field but that papers containing an activator such as albumin added as a pinocytosis inducer - which allows the penetration of metaldehyde through the foot of the slug - are the most effective to destroy it.

EXAMPLE 2

  Another composition "D" is prepared in a manner analogous to that used for composition "A" of Example 1, except that it contains 2% metaldehyde. When it is deposited on a paper waterproofed with water and which is then tested as described in Example 1, the results obtained

  are similar to those given by the composition "B".

  Similar results are also obtained when the composition "D" is deposited on one face of a porous ceramic tile, the other side thereof

  having been treated with acid to provide an impermeable surface.

EXAMPLE 3

  Square sheets of paper measuring 15 cm on one side, coated on one side with a polythene thread and on the other side a coating about 1 mm thick with a gelatin-bonded molluscanic composition are deposited regularly on a uniform meadow and the number of slugs

dead is counted every morning.

  * Molluscicidal composition I: gelatin + 4% metaldehyde + bran * Molluscicidal composition II: gelatin + 4% metaldehyde + bran

+ 0.35% of T.G.C.

  Number of dead slugs per day Coated I Coated II

26

8 15

8 5

7 4

4 6

4 5

3 4

Total: 49 65

EXAMPLE 4

  Results similar to those of ExempLes 1, 2 and 3 are obtained by adding 3% of acetate in compositions "A" and "D" and TGC which are described in sodium in place of albumin.

the composition II.

EXAMPLE 5

  Example 3 is repeated using also a composition III containing

sodium lauryl sulfate.

  * Molluscicidal composition I: gelatin + * Mollusquicidal composition II: gelatin + Molusicidal composition III: gelatin + Molluscicidal composition III: gelatin + +

4% metaldehyde + bran

4% metaldehyde + sound

0.35% TGC.

  4% metaldehyde + 0.4% sodium laurylsulfate Number of slugs per day Coated I Totals: 12 Coating II Coating III Of course, the present invention is by no means limited to the examples

  and modes of implementation mentioned above; it is likely to

  Many variants accessible to those skilled in the art, depending on the applications

  visages and without departing from the spirit of the invention.

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Claims (14)

REVENDI A.TIONS   1.- Medium for fighting terrestrial molluscs, characterized in that it comprises an absorbent substrate, one side of which is impervious to water   and the other is coated with a molluscan composition.   2. Medium according to claim 1, characterized in that the substrate is paper.   3. Medium according to claim 1 or 2, characterized in that the compound   molluscicidal formulation contains gelatin.   4. Composition according to claim 1, 2 or 3, characterized in that   the molluscan composition contains an attractant for the mollusc.   5. Medium according to any one of claims 4, characterized   in that the molluscicidal composition contains an enzyme or a protein which activates the mollusquicide.   6. Medium according to claim 5, characterized in that the enzyme or the protein is selected from the group formed by ribonuclease, blood albumin, bovine serum albumin, horseradish peroxidase, albumin. of   egg and PFC enzyme (an enzyme from A.B.M. Chemicals).   7. Medium according to claim 5 or 6, characterized in that the   portion of enzyme or protein is between 0.5 and 10% by weight of the molluscicidal composition.   8. Medium according to any one of claims 1 to 4, characterized   in that the molluscicidal composition contains a surfactant.   9. Medium according to claim 8, characterized in that the surfactant   active ingredient is sodium tauroglycocholate, sodium taurocholate or sodium deoxycholate. -   10. The medium according to any one of claims 1 to 4, characterized   in that the molluscicidal composition contains sodium acetate.   11. The medium according to any one of claims 5 to 10, characterized   in that the mollusquicide is metaldehyde and is present in the   composition at 2.0 to 2.5% by weight.   Medium according to one of Claims 5 to 11, characterized   in that the mollusquicide is metaldehyde and is applied on the   substrate at a rate of 20 to 24 g / m2. 9 2482829   13. The medium according to any one of claims 1 to 12, characterized   in that the coating of moli: isquicide composition has a thickness of between 0.5 and 1.5 mm.   14. A means according to any one of claims 13, characterized   in that the substrate is paper on one side of which is fixed a film of synthetic polymer.