Penoxsulam is sulfonamide and triazolopyrimidine herbicide that acts as an acetolactate synthase inhibitor. It is primarily used for rice production. Penoxsulam's HRAC classification is Group B, Group 2, as it is an acetohydroxyacid synthase inhibitor. Chemically it is a selective post-emergence and early post-emergence ALS inhibitor with systemic activity through both foliar uptake and root translocation, providing control of broadleaf weeds and several sedges in paddy fields. Technical formulations are supplied as suspension concentrates, water dispersible granules and suspension emulsions to optimize crop safety and spray retention. From a physical chemistry perspective penoxsulam shows low to moderate water solubility, low vapor pressure and a low octanol water partition coefficient consistent with limited potential for bioaccumulation. Environmental fate studies report moderate persistence in flooded paddy systems with primary degradation by microbial pathways and transformation to polar metabolites; soil half life depends on conditions but is generally consistent with a low to moderate persistence classification. Mode of action resistance management recommends rotation with herbicides from different HRAC groups and tank mixtures where label permits to reduce selection pressure on ALS target sites.
Parent: Penoxsulam
Typical industrial technical material for penoxsulam is manufactured to high purity with common target specifications of at least 95 percent active ingredient by weight. Related compounds and process impurities are normally controlled tightly; manufacturers commonly limit total related compounds to the range of 1.0 to 3.0 percent by weight, with individual unspecified impurities typically controlled at 0.5 to 1.0 percent maximum each. Typical impurity classes encountered in production include N-oxidation products, desalkyl or desalkoxy variants from incomplete substitutions, hydrolysis products of the sulfonamide linkage and trace amounts of residual solvents from synthesis. Heavy metals and chlorinated byproducts are routinely controlled to low ppm limits consistent with regulatory requirements. Exact impurity names and numerical limits vary by manufacturer and by the registered technical specification for a given market, so refer to the supplier’s certificate of analysis and safety data sheet for the certified impurity profile for a specific batch.
This denotes a suspension emulsion formulation that combines 0.97 percent weight by weight penoxsulam with 38.8 percent butachlor as active ingredients. The combination pairs penoxsulam’s post-emergence ALS inhibition spectrum with butachlor’s pre-emergence grass and broadleaf activity to broaden weed control in rice. SE indicates the formulation type and users should follow label directions for application rate timing and water management to achieve crop safety and efficacy.
There is no single global trade name for a penoxsulam plus cyhalofop combination. Trade names differ by manufacturer and by country. Products that combine an ALS inhibitor such as penoxsulam with a grass-selective herbicide such as cyhalofop-butyl are marketed under different brand names by different registrants. Check the product label or contact the local registrant to confirm the commercial trade name for a specific market.
The technical name corresponds to the active ingredient penoxsulam. Crystal Penoxa is a commercial or brand designation; the technical or generic name of the active molecule used in that product is penoxsulam. Consult the product label or certificate of analysis for the exact technical material designation used by the supplier.
When used according to the approved label and safety data sheet, penoxsulam is considered to have low acute mammalian toxicity and acceptable crop safety in recommended uses, but users must follow personal protective equipment and application restrictions. Penoxsulam can pose risks to aquatic plants, certain algae and non target aquatic organisms, so buffer zones and use restrictions around water bodies are typically required. Environmental risk varies with formulation, dose, local water management and application practice, so always adhere to the registered label, local regulations and integrated weed management recommendations to minimize off target impacts.
