Oxadiazon, under the trade name Ronstar, is an oxadiazole herbicide that has contact, selective, and photosynthesis-inhibiting properties and is used to control weeds in rice fields post-emergence and in onion fields post-planting and pre-emergence. This herbicide works by inhibiting the enzyme protoporphyrinogen oxidase, thus preventing the growth and development of weeds that have sprouted and, due to its persistence throughout the season, leads to wilting and cessation of their growth. Oxadiazon quickly penetrates the weed and is absorbed and metabolized through the stem and leaves of the weed, and its residue does not accumulate in the plant. This is a triple-purpose herbicide that is used to control broadleaf, narrowleaf, and grass weeds.