Substituted spiro compounds (I) are new. Substituted spiro compounds of formula (I) are new. W 1>；H, alkyl, alkenyl, alkynyl, optionally substituted cycloalkyl, halo, alkoxy, alkenyloxy, haloalkyl, haloalkoxy or CN； X : halo, alkyl, alkenyl, alkynyl, optionally substituted cycloalkyl, alkoxy, alkenyloxy, alkylthio, alkylsulfinyl, alkylsulfonyl, haloalkyl, haloalkoxy, haloalkenyloxy, nitro or CN； Y 1>；, Z : H, alkyl, alkenyl, alkynyl, optionally substituted cycloalkyl, alkoxy, halo, haloalkyl, haloalkoxy, CN, nitro or optionally substituted (het)aryl； A, B 1>；tetrahydrofuran ring or tetrahydropyran ring (optionally substituted by alkyl, haloalkyl, alkoxy, alkoxyalkyl or phenyl)； D 1>；NH or O； Q 1>；, Q 2>；H, alkyl, haloalkyl or alkoxy； G : H, -C(=O)-R 1>；, -C(=L)-M-R 2>；, -SO 2-R 3>；, -P(=L)(R 4>；)(R 5>；), E or -C(L)-N(R 6>；)(R 7>；)； E : metal ion or ammonium ion； L, M : O or S； R 1>；optionally halo or CN substituted alkyl, alkenyl, alkoxyalkyl, alkylthioalkyl or polyalkoxyalkyl, or heterocycle optionally substituted by halo, alkyl or alkoxy substituted cycloalkyl, or optionally substituted phenyl, phenylalkyl, hetaryl, phenoxyalkyl or hetaryloxyalkyl； R 2>；optionally halo or CN substituted alkyl, alkenyl, alkoxyalkyl or polyalkoxyalkyl, or optionally substituted cycloalkyl, phenyl or benzyl； R 3>；-R 5>；optionally halo substituted alkyl, alkoxy, alkylamino, dialkylamino, alkylthio, alkenylthio or cycloalkylthio, or optionally substituted phenyl, benzyl, phenoxy or phenylthio； and either R 6>；, R 7>；H, optionally halo or CN substituted alkyl, cycloalkyl, alkenyl, alkoxy or alkoxyalkyl, optionally substituted phenyl or benzyl； or R 6>；R 7>；N : optionally substituted cycle containing optionally O or S. Independent claims are included for: (1) the preparation of (I)； (2) an agent to combat parasite and or undesirable plant growth comprising (I)； (3) the preparation of the agent comprising mixing (I) with a diluting agent and/or a
