Methods of soil pest control

1. A method of controlling and/or preventing soil-dwelling pests in useful plants comprising applying to the locus of the useful plant or treating plant propagation material thereof with a compound of formula I

wherein

—B 1 —B 2 —B 3 — is —C═N—O—, —C═N—CH 2 —, —C═CH 2 —O— or —N—CH 2 —CH 2 —;

L is a direct bond or methylene;

A 1 and A 2 are C—H, or one of A 1 and A 2 is C—H and the other is N;

X 1 is group X

R 1 is C 1 -C 4 alkyl, C 1 -C 4 haloalkyl or C 3 -C 6 cycloalkyl;

R 2 is chlorodifluoromethyl or trifluoromethyl;

each R 3 is independently bromo, chloro, fluoro or trifluoromethyl;

R 4 is hydrogen, halogen, methyl, halomethyl or cyano;

R 5 is hydrogen;

or R 4 and R 5 together form a bridging 1,3-butadiene group;

p is 2 or 3,

and where the soil-dwelling pest includes at least one pest chosen from a wireworm; a grub; a white grub; a termite; a subterraneous stinkbug; a cutworm; a millipede; and a broca gigante.

2. A method according to claim 1 , wherein the compound of formula I is applied directly to soil.

3. A method according to claim 1 wherein the compound of formula I is applied to soil by treatment of a seed with a compound of formula I.

4. A method comprising applying a compound of formula I as defined in claim 1 to a field of corn plants, before, during or after planting, and wherein the application of the compound of formula I comprises applying the compound of formula I directly to soil.

5. A method according to claim 3 , wherein the compound of formula I is applied in-furrow.

6. A method according to claim 1 , wherein A 1 and A 2 are C—H, R 2 is trifluoromethyl, and R 5 is hydrogen, wherein the soil-dwelling pests are optionally wireworms.

7. A method according to claim 1 , wherein A 1 and A 2 are C—H, R 2 is trifluoromethyl, R 4 is methyl, R 5 is hydrogen, each R 3 is chlorine, p is 2, wherein the soil-dwelling pests are optionally wireworms.

8. A method according to claim 1 , wherein R 1 is methyl, ethyl, propyl, butyl, cyclopropyl, cyclobutyl, trifluoroethyl, difluoroethyl, wherein the soil-dwelling pests are optionally wireworms.

9. A method according to claim 1 , wherein R 1 is ethyl or trifluoroethyl, wherein the soil-dwelling pests are optionally wireworms.

10. A method according to claim 1 , wherein X 1 is 3,5-dichloro-phenyl, 3,5-dichloro-4-fluorophenyl-, 3,4,5-trichlorophenyl-, or 3,5-bis(trifluoromethyl)phenyl, wherein the soil-dwelling pests are optionally wireworms.

11. A method according to claim 1 , wherein —B 1 —B 2 —B 3 — is —C═N—O—, wherein the soil-dwelling pests are optionally wireworms.

12. A method according to claim 1 , wherein the compound of formula I is a mixture of compounds I* and I**

wherein the molar proportion of compound I** compared to the total amount of both enantiomers is greater than 50%, wherein the soil-dwelling pests are optionally wireworms.

13. A method according to claim 1 , wherein the compound of formula I is a mixture of compounds I′ and I″

(S═S stereochemistry, R═R stereochemistry)

wherein the molar proportion of compound I″ compared to the total amount of both enantiomers is greater than 50%, preferably wherein the soil-dwelling pests are wireworms.

14. A method for obtaining regulatory approval for the use of one or more of a compound of formula I as defined in claim 1 to control a pest selected from wireworms, grubs, in particular white grubs, termites, subterraneous stinkbugs, cutworms, millipedes and broca gigante, comprising at least one step of referring to, submitting or relying on biological data showing that said active ingredient reduces insect pressure.