Oil-based suspension concentrate (A) comprises: at least one substituted heteroaryl compound (I), that is solid at room temperature, in form its isomeric mixture or pure isomer; at least one penetration promoter, which is an alkanol-alkoxylate compound (II); at least one vegetable oil; at least one non-ionic surfactant comprising polyethyleneoxide-polypropyleneoxide-4-butoxybuthylether, polyethyleneglycolether of linear alcohols and/or conversion products of fatty acids with ethylene oxide; and/or at least one anionic surfactant. Oil-based suspension concentrate (A) comprises: at least one substituted heteroaryl compound of formula (I), that is solid at room temperature, in form its isomeric mixture or pure isomer; at least one penetration promoter, which is an alkanol-alkoxylate compound of formula (R 8>-O-(EO) p-(PO) q-R 9>) (II); at least one vegetable oil; at least one non-ionic surfactant comprising polyethyleneoxide-polypropyleneoxide-4-butoxybuthylether, polyethyleneglycolether of linear alcohols and/o
