The German cockroach is resistant to several organochlorine, organophosphorus,
carbamate and pyrethroid insecticides (7). The Oriental cockroach, the American
cockroach and the large brown cockroach (Periplaneta brunnae) have developed
little resistance, mainly to DDT and chlordane. Recently, the American cockroach
has been found to be resistant to trichlorfon in China and the large brown
cockroach to diazinon in the USA.