Clomazone is an
agricultural
Agriculture encompasses crop and livestock production, aquaculture, and forestry for food and non-food products. Agriculture was a key factor in the rise of sedentary human civilization, whereby farming of domesticated species created f ...
herbicide
Herbicides (, ), also commonly known as weed killers, are substances used to control undesired plants, also known as weeds.EPA. February 201Pesticides Industry. Sales and Usage 2006 and 2007: Market Estimates. Summary in press releasMain page f ...
, and has been the active ingredient of products named "Command" and "Commence". The molecule consists of a 2-chlorobenzyl group bound to a N-O heterocycle called isoxazolidinone. It is a white solid.
Clomazone was first registered by the USEPA on March 8, 1993, and was commercialized by FMC Corporation. It is used for broadleaf weed control in several crops, including soybeans, peas, maize, oilseed rape, sugar cane, cassava, pumpkins and tobacco. It may be applied pre-emergence of incorporated before planting the crop. Clomazone is relatively volatile (vapor pressure is 19.2 mPa) and vapors induce striking visual symptoms on non-target sensitive plants. Clomazone undergoes biological degradation, exhibiting a soil
half life Half-life is a mathematical and scientific description of exponential or gradual decay.
Half-life, half life or halflife may also refer to:
Film
* ''Half-Life'' (film), a 2008 independent film by Jennifer Phang
* '' Half Life: A Parable for t ...
of one to four months. Adsorption of the herbicide to soil solids slows degradation and volatilization. Encapsulation helps reduce volatility and therefore reduces off-target damage to sensitive plants.
Clomazone suppresses the
biosynthesis
Biosynthesis, i.e., chemical synthesis occurring in biological contexts, is a term most often referring to multi-step, enzyme-Catalysis, catalyzed processes where chemical substances absorbed as nutrients (or previously converted through biosynthe ...
of
chlorophyll
Chlorophyll is any of several related green pigments found in cyanobacteria and in the chloroplasts of algae and plants. Its name is derived from the Greek words (, "pale green") and (, "leaf"). Chlorophyll allows plants to absorb energy ...
and other plant pigments.
[Gara, Pedro M. David; Rosso, Janina A.; Martin, Marcela V.; Bosio, Gabriela N.; Gonzalez, Monica C.; Martire, Daniel O. "Characterization of humic substances and their role in photochemical processes of environmental interest" Trends in Photochemistry & Photobiology 2011, vol. 13, pages 51-70.]
References
{{Herbicides
Herbicides
2-Chlorophenyl compounds
Isoxazolidinones
Group 13 herbicides