Abstract: A 1,2,3-thiadiazole derivative represented by general formula (I) or a salt thereof: wherein R1 is H, (halo) C1-C4 alkyl, 5- or 6-membered heterocycle containing 1 to 3 same or different O, N or S or the like, A is a group of the following formulas: wherein R2 and R3 are H, halogen, cyano, formyl, alkylthio, alkoxycarbonyl, substituted or unsubstituted phenyl, or the like, or R2 and R3, taken conjointly, may form a 3- to 7-membered ring including a C2-C6 alkylene group which may be intercepted by —O—, —S(O)n— (n is 0-2), —CO— or —NR8— (R8 is H, halogen or the like), B is cyano or an unsubstituted or substituted 5- or 6-membered heterocycle containing 1-3 hetero atoms selected from O, N and S, and m is 0-4; salts thereof; an agrohorticultural disease controller containing said derivative or salt; and method for using said disease controller.

Abstract: A 1,2,3-thiadiazole derivative represented by general formula (I) or a salt thereof: wherein R1 is H, (halo) C1-C4 alkyl, 5- or 6-membered heterocycle containing 1 to 3 same or different O, N or S, A is a group of the following formulas: wherein R2 and R3 are H, halogen, cyano, formyl, alkylthio, alkoxycarbonyl, substituted or unsubstituted phenyl, B is cyano or an unsubstituted or substituted 5- or 6-membered heterocycle containing 1-3 hetero atoms selected from O, N and S, and m is 0-4; an agrohorticultural disease controller containing said derivative.