Penoxsulam was registered with the EPA for aquatic use in 2009.
The active ingredient is
It is a liquid and is used for large-scale control of submerged,
emergent and floating-leaf vegetation.
Aquatic Use and Considerations
Penoxsulam is a systemic herbicide that moves throughout the plant
tissue and prevents plants from producing a necessary enzyme,
synthase (ALS), which is not found in animals. Susceptible plants
will stop growing soon after treatment and become reddish at the
tips of the
plant. Plant death and decomposition will occur gradually over
several weeks to months. Penoxsulam should be applied to plants
that are actively
growing; mature plants require a higher concentration of herbicide
and a longer contact time.
Penoxsulam must remain in contact with plants for around 60 days. A
supplemental “bump” treatment may be needed to maintain the
concentration for the required contact time. Because of this long
contact period, penoxsulam is likely to be used for larger-scale or
treatments and should not be used where rapid dilution can occur
such as spot treatments or moving water.
Penoxsulam may be used to treat the invasive Eurasian watermilfoil
(Myriophyllum spicatum). In other parts of the country, it is
valuable as a
rotational herbicide against the invasive plant hydrilla (Hydrilla
verticillata). Desirable native species that may also be affected
pondweed (Stuckenia pectinata), Illinois pondweed (Potamogeton
illinoensis), pickerelweed (Pontederia cordata), duckweeds (Lemna
arrowhead (Sagittaria spp.).
It is important to note that repeated use of herbicides with the
same mode of action can lead to herbicide-resistant plants, even in
More resistant weeds have developed to the ALS inhibitor herbicides
than to other herbicide types, and so this mechanism of action may
susceptible to developing resistance. In order to prevent herbicide
resistance, avoid using the same type of herbicides year after
year, and when
possible, use non-herbicide methods of control instead.
Penoxsulam is a new post-emergence rice herbicide for applications
in drained and semi-flooded paddies. It is an acetolactate synthase
inhibitor herbicide developed in the mid-2000s. This substance is
designed to control existing broadleaf weeds and similar plants in
lawns, rice fields and cereal crops. While penoxsulam is not
effective against most grass species, it can be used to control a
few specific weed grass species. Penoxsulam was originally designed
for use in rice fields and is capable of killing several pest
grasses that prefer wet environments.
We have successfully synthesized standards of the Penoxsulam. This
will be of interest to agrochemical companies and analytical labs.
|Specification||98% Tech, 50%OD, 25g/l OD, 10%OD,5%OD|
|Toxicology||Oral Acute oral LD50 for rats >5000 mg/kg. Skin and eye Acute
percutaneous LD50 for rabbits > 5000 mg/kg; very slight,
transient irritation. Inhalation LC50 for rats >3.50 mg/l
(highest attainable concentration). NOEL For rats 500 mg/kg b.w.
daily (maternal), 1000 mg/kg b.w. daily (embryo-foetal). Toxicity
class EPA (formulation) III (GR, SC)|
|Applications||Mode of action Absorbed via leaves, stems and roots. Symptoms include almost
immediate growth inhibition, a chlorotic growing point with
necrosis of the terminal bud, resulting in plant death in 2 to 4
weeks. Applied pre-emergence, post-emergence and water-applied. Uses Provides control of Echinochloa spp., as well as many broadleaf,
sedge and aquatic weeds in rice. Penoxsulam provides residual weed
control, depending on soil type and use rate. In tropical rice,
application will be at 10-15 g/ha; in temperate rice, 20-50 g/ha.
Primary use will be a post-emergence application in dry-seeded,
water-seeded and transplanted rice.|
|Package||25kg/drum, 200l/drum, 20l/drum, etc|