The present invention relates to substituted 1,2,5-oxadiazole compounds of formula I and N-oxides and salts thereof and compositions containing them. The invention also relates to the use of a 1,2,5-oxadiazole compound or a composition comprising such a compound for controlling unwanted plants. The invention further relates to a method for applying such compounds. In formula I, the variables have the following meanings: R is for example hydrogen, cyano, nitro, halogen, C1-C6-alkyl, C3-C7-cycloalkyl, C3-C7-cycloalkyl-C1-C4-alkyl. , C1-C6-haloalkyl, C2-C6-alkenyl, C2-C6-haloalkenyl, C2-C6-alkynyl, C2-C6-haloalkynyl, C1-C4-alkoxy-C1-C4-alkyl, C1-C4-halo Alkoxy-C1-C4-alkyl, O-Ra, Z-S (O) n-Rb, Z-C (= O) -Rc, Z-C (= O) -ORd, Z-C (= O)- NReRf, Z-NRgRh, Z-phenyl, Z-heterocyclyl and the like； R1 is, for example, Z1-cyano, halogen, nitro, C1-C8-alkyl, C2-C8-alkeni , C2-C8-alkynyl, C1-C8-haloalkyl, C1-C8-alkoxy, C1-C4-alkoxy-C1-C4-alkyl, Z1-C1-C4-alkoxy-C1-C4-alkoxy, C1-C4-alkylthio -C1-C4-alkyl, Z1-C1-C4-alkylthio-C1-C4-alkylthio, C2-C6-alkenyloxy, C2-C6-alkynyloxy, C1-C6-haloalkoxy, C1-C4-haloalkoxy-C1 -C4-alkyl, Z1-C1-C4-haloalkoxy-C1-C4-alkoxy, Z1-S (O) k-R1b, Z1-phenoxy and Z1-heterocyclyloxy； R2, R3 are the same or different For example, hydrogen, halogen, Z2-OH, Z2-NO2, Z2-cyano, C1 C6-alkyl, C2-C8-alkenyl, C2-C8-alkynyl, Z2-C3-C10-cycloalkyl, Z2-C3-C10-cycloalkoxy, C1-C8-haloalkyl, Z2-C1-C8-alkoxy, Z2- C1-C8-haloalkoxy, Z2-C1-C4-alkoxy-C1-C4-alkoxy, Z2-C1-C4-alkylthio-C1-C4-alkylthio, Z2-C2-C8-alkenyloxy, Z2-C2-C8- Alkynyloxy, Z2-C1-C8-haloalkoxy, Z2-C2-C8-haloalkenyloxy, Z2-C2-C8-haloalkynyloxy, Z2-C1-C4-haloalkoxy-C1-C4-alkoxy, Z2- ( Tri-C1-C4-alkyl) silyl, Z2-S (O) k-R2b, Z2-C (= O) -R2c, Z2-C (= O) -OR2d, Z2-C (= O) -NR2eR2f, Z2-NR2gR2h, Z2a-phenyl and Z2a-heterocyclyl； R4 is hydrogen, halogen, cyano, nitro, Selected from the group consisting of C1-C4-alkyl and C1-C4-haloalkyl本発明は、式Ｉの置換型１，２，５－オキサジアゾール化合物並びにそのＮ－オキシド及び塩と、それを含む組成物に関する。本発明はまた、望まれていない植物を防除するための１，２，５－オキ
