October
6, 2004 - REPORT
CANADA: Proposed
Regulatory Decision Document PRDD2004-4. The technical
grade active ingredient florasulam associated end-use
product EF-1343 Suspension Concentrate Herbicide for
the control of broadleaf weeds in spring wheat, including
durum, spring barley and oats (tank-mix only)
are eligible for full registration under Section 13
of the Pest Control Products (PCP) Regulations. These
products were granted temporary registration as per
Regulatory Note REG2001-12. This Proposed Regulatory
Decision Document (PRDD) provides a summary of the data
reviewed and the rationale for the proposed regulatory
decision. The Canadian Pest Management Regulatory Agency
(PMRA) will accept written comments on the proposal
up to 45 days from the date of publication of this document.
EF-1343 Suspension Concentrate Herbicide "is
to be used only in the prarie provinces and the Peace
River region of British Columbia, which are the
major cereal production areas of Canada (page 4)."
(See also the Sept 27, 2001, report from the Canadian
PMRA.) (102 pages)
|
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15149133
Commun Agric
Appl Biol Sci. 2003;68(4 Pt A):381-90.
Study
of the selectivity of PRIMSTAR (fluroxypyr + florasulam) in
two key grass species (FESRU & LOLPE) grown for seed production.
Rijckaert
G, Lepiece D.
Depart.
Plant Genetics and Breeding, B 9090 Melle, Belgium.
PRIMSTAR
is a SE (Suspo-Emulsion) formulation containing 2.5 g florasulam
& 100 g fluroxypyr-MHE per liter. PRIMSTAR is registered
in Belgium since beginning 2003 as selective herbicide to control
the most important broadleaved weeds in wheat & barley.
The weed-spectrum of this product is now completely evaluated.
Nevertheless, it was interesting to study this product in grass
seed production. The prime objective of this study was to investigate
the crop safety of PRIMSTAR applied on the two key species of
grass produced for seed. The two species in the study were:
1) FESRU--Creeping fescue Festuca rubra rubra cv. NEVSKI sown
at 15 kg/ha, June 6, 2001.
2) LOLPE--Perrenial ryegrass Lolium perenne cv. MERBO sown at
17.5 kg/ha, October 5, 2001.
The trial was a randomized complete bloc design in 4 reps. The
contractor was REDEBEL, a GEP registered independent company.
The trial site was located in Melle, Belgium.
TREATMENTS: PRIMUS 100 mL, PRIMUS 200 mL, PRIMSTAR 1.05 L/ha,
PRIMSTAR 2.1 L/ha, BASAGRAN DP 3 L/ha, BASAGRAN DP 6 L/ha. The
treatments were applied March 29, 2002 on a maintained weed-free
field.
CONCLUSION: PRIMSTAR appeared to be highly selective in FESRU
& LOLPE intended for seed production. All evaluations observed
were positive. Only some light visual crop injuries were possible,
but mostly negligible and the symptoms disappeared very soon
within 35 DAA. Treatments with PRIMSTAR had no effect at all
on the main seed yield characteristics i.e. seed yield, thousand
seed weight and germination power. Treatments with the reference
BASAGRAN DP (bentazone + dichlorprop) brought about a more aggressive
action in comparison with the PRIMSTAR treatments in terms of
vegetative crop inhibition (reduced straw yield for perennial
ryegrass).
PMID: 15149133
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12425099
Meded Rijksuniv
Gent Fak Landbouwkd Toegep Biol Wet. 2001;66(2b):747-52.
Selectivity
of florasulam in 4 grass species during the seed harvest year.
Rijckaert
G, Lepiece D.
Dept. Plant
Genetics and Breeding-CLO-Gent, Caritasstraat 21, B-9090 Melle,
Belgium.
Results
from one year indicated that florasulam (Primus) and its combination
with fluorxypyr applied in spring of the seed harvest year,
were completely selective in seed crops of 4 grass species;
namely Agrostis stolonifera, Festuca rubra rubra, Koeleria macrantha
and Lolium multiflorum. Experimental treatments also included
a reference product i.e. bentazone + dichlorprop-P and an untreated
control; in total 7 treatments were involved. The prime objective
of this study was to investigate not only the effect on vegetative
crop growth, but also the impact on generative growth. The main
topics were: visual phytotoxicity, lodging, seed yield, straw
yield, thousand seed weight, germination capacity, cleaning
efficiency, harvest index, seed number per unit area and ear
density. The reference treatments (bentazone + dichlorprop-P)
were insufficiently selective in Koeleria spp. for vegetative
parameters and seed yield, and less selective in Festuca spp.
during establishment year but without any effect on seed yield.
The so-called "non-sitting" seed crops following above
treatments in creeping fescue and Italian ryegrass could be
attributed to an inhibition effect.
PMID: 12425099
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12425093
Meded Rijksuniv
Gent Fak Landbouwkd Toegep Biol Wet. 2001;66(2b):681-704.
Primus (florasulam 50 G/L), a new triazolopyrimidine
sulfonanilide herbicide to control broad-leaved weeds in maize
when applied in early postemergence (1 to 6 leaf stage of maize).
Preliminary results.
Lepiece
D, Salembier JF, Thompson A.
Dow
AgroSciences, Belgium.
OBJECTIVE:
PRIMUS was developed in maize in Belgium in 1999 and 2000 in
the course of research into limiting or replacing the use of
triazines in maize. One of the imperatives of this research
was to find the lowest possible residue content (MRL).
SELECTIVITY TEST: An application of florasulam, at the dose
of 5 g of active substance (a.s.) at the 2 to 3 leaf stage of
the maize was found to be selective on 132 (in 1999) and 126
(in 2000) varieties of maize.
EFFICACY TEST: Florasulam was tested at doses of between 1 and
5 g a.s./hectare. The treatments were applied in early postemergence
at the 3-5 leaf stage of the maize or in 2 separate applications:
at the 1 leaf stage with a dose of 2 g a.s. florasulam at the
4 leaf stage with a dose of 2 g a.s. florasulam The herbicide
was fully effective on the sensitive flora. A summary of the
results is presented. A detailed weed spectrum is defined.
PROGRAMMES: Herbicide programmes were developed on the basis
of these findings. The results showed that the best partners
for florasulam were triketones (sulcotrione and mesotrione)
in very low doses. Sulcotrione was applied at doses of 75 to
150 g a.s./ha and mesotrione at 25 to 50 g a.s./ha. Triple mixes
of florasulam + triketone + nicosulfuron in very low doses and
1 or 2 applications were also tested. The results were highly
encouraging and this work should lead to practical recommendations.
PHYTOTOXICITY: Phytotoxicity was observed on some occasions.
The phytotoxicity results for the different figures seem, however,
to depend more on the climate (difference between daytime and
night-time temperatures just before and after the treatment)
than on the products tested in the mixes. However, the florasulam
+ nicosulfuron (sulfonyl-urea antigrasses) may sometimes cause
serious problems with selectivity. The phytotoxicity noted in
the tests was usually short-lived (30 days).
CONCLUSION: The results of the tests show that it is possible
to consider replacing atrazine-based programmes with very low
doses of modern herbicides applied at early stages of the maize.
A mixture of active substances is vital. Repeated very low doses
at the 1/2 and 4/5 leaf stages of the maize were found to be
the most effective.
PMID: 12425093
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12233189
Pest Manag
Sci. 2002 Sep;58(9):964-6.
Establishment
of the baseline sensitivity and monitoring response of Papaver
rhoeas populations to florasulam.
Paterson
EA, Shenton ZL, Straszewski AE.
Dow
AgroSciences Ltd,
3 Milton Park, Abingdon, Oxon OX14 4RN, UK.
In accordance
with the EPPO guideline for the efficacy evaluation of plant
protection products, resistance risk analysis PP 1/213(1), a
method was established to determine the baseline sensitivity
of key weed species to florasulam, a new triazolopyrimidine
sulfonanilide herbicide for post-emergence control of dicotyledonous
weeds in cereals. The aim of the baseline monitoring project
was to understand the natural variation in response to florasulam
of diverse populations of Papaver rhoeas at the time of product
launch. The method entailed seed collection from representative
agricultural areas throughout Europe. The seed was subjected
to glasshouse tests where dose-response studies were conducted
and ED80 values generated. This enabled a sensitivity index
to be calculated for each country, giving an indication of the
variation in P rhoeas response to florasulam in the populations
tested.
PMID: 12233189
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11052731
J Agric
Food Chem. 2000 Oct;48(10):4757-66.
Effect
of temperature and moisture on the degradation and sorption
of florasulam and 5-hydroxyflorasulam in soil.
Krieger
MS, Pillar F, Ostrander JA.
Dow
AgroSciences, Environmental Chemistry Laboratory, 9330
Zionsville Road, Indianapolis, Indiana 46268, USA. mkrieger@dowagro.com
The degradation
rate and sorption characteristics of the triazolopyrimidine
sulfonanilide herbicide florasulam and its principal degradation
product 5-hydroxyflorasulam (5-OH-florasulam) were determined
as a function of temperature and moisture in three different
soils. The half-life for degradation of florasulam ranged from
1.0 to 8.5 days at 20-25 degrees C and from 6.4 to 85 days at
5 degrees C. The half-life for degradation of 5-OH-florasulam
ranged from 8 to 36 days at 20-25 degrees C and from 43 to 78
days at 5 degrees C. The degradation rate of both compounds
was strongly influenced by temperature, with activation energies
ranging from 57 to 95 kJ/mol for florasulam and from 27 to 74
kJ/mol for 5-OH florasulam. Soil moisture content had negligible
impact on the degradation rate. Apparent (nonequilibrium) sorption
coefficients for florasulam and 5-OH-florasulam at 0 days after
treatment (DAT) were 0.1-0.6 L/kg and increased linearly with
time for both florasulam and 5-OH-florasulam (r(2) > 0.90)
to levels as high as 12-23 L/kg. Heats of adsorption were calculated
on one soil as a function of time. Heat of adsorption values
for both florasulam and 5-OH-florasulam increased as incubation
time increased and the amount of each compound decreased; values
were near 0 kJ/mol initially and increased to a maximum of 91
and 66 kJ/mol for florasulam and 5-OH-florasulam, respectively.
PMID: 11052731
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=10956175
J Agric
Food Chem. 2000 Aug;48(8):3710-7.
Photolytic
degradation of florasulam on soil and in water.
Krieger
MS, Yoder RN, Gibson R.
Dow
AgroSciences, Environmental Chemistry Laboratory,
Indianapolis, Indiana 46268, USA. mkrieger@dowagro.com
The rate
and pathway of degradation in the presence of light for the
triazolopyrimidine herbicide florasulam was determined on soil
and in aqueous systems. Florasulam was exposed to natural sunlight
for up to 32 days; solar irradiance was measured with either
chemical actinometers or by radiometry. The quantum yield for
direct photodegradation in a sterile, buffered aqueous solution
was determined to be 0.096; an analogous quantum yield for the
sum of direct and indirect photodegradation on soil was 0.245.
The quantum yields were used to estimate half-lives due to photodegradation
as a function of season and temperature. Estimated half-lives
due to photodegradation in summer at 40 degrees N latitude were
14 days on soil and 36 days in sterile, buffered water. Photodegradation
was much faster in a natural water system, with a measured half-life
of 3.3 days in summer at 51.5 degrees N latitude, indicating
that indirect photolytic processes will be important contributors
to photodegradation of florasulam in aqueous environments.
PMID: 10956175
[PubMed - indexed for MEDLINE]
From
Toxline at Toxnet
MEDEDELINGEN
FACULTEIT LANDBOUWKUNDIGE EN TOEGEPASTE BIOLOGISCHE WETENSCHAPPEN
UNIVERSITEIT GENT; 63 (3A). 1998.
735-749.
Florasulam
Primus, a new selective triazolopyrimidine sulfonanilide (ALS)
herbicide to control broad-leaved weeds in cereals; Belgian
results from 1994 to 1997.
LEPIECE
D, THOMPSON A, MCREATH A
Dow
Agro-Sci.,
Laarstr. 17, B-2610 Wilrijk, Belgium.
BIOSIS COPYRIGHT: BIOL ABS. Florasulam was evaluated for 3 years
under Belgian climatic conditions. Florasulam was consistently
highly selective in cereals and proved very effective when applied
at very low rates on many dicot weeds such as Galium aparine,
Stellaria media, Matricaria spp. and other members of the Compositae
& Cruciferae weeds. Florasulam has no activity on grass
weeds. Florasulam has a wide window of application and may be
applied from BBCH 14 until BBCH 39 and even later of the cereal
crop. Florasulam can be applied in tank mixture with a range
of other herbicides: phenoxies, PPO inhibitors, DFF, HBN, ACCase
inhibitors such as clodinafop, ALS inhibitors, substituted ureas.
Florasulam may also be tank-mixed with mineral oil or pure liquid
fertilizer. Those two combinations increase the effectiveness
of florasulam and the speed in which symptoms appear. Florasulam
was tested for 4 years at the University of Gent to evaluate
the persistence in soil. The product was not persistent an [abstract
truncated]
From
Toxline at Toxnet
Source:
218TH NATIONAL MEETING OF THE AMERICAN CHEMICAL SOCIETY, PARTS
1 AND 2, NEW ORLEANS, LOUISIANA, USA, AUGUST 22-26, 1999.YABSTRACTS
OF PAPERS AMERICAN CHEMICAL SOCIETY; 218 (1-2). 1999.
AGRO 129.
Comparative
uptake, translocation, and metabolism of florasulam in wheat
and broadleaf weeds.
DEBOER GJ, THORNBURGH S, CLEVELAND J,
EHR RJ
Discovery
Research, Dow AgroSciences,
9330 Zionsville Road, Indianapolis, IN, USA.
BIOSIS COPYRIGHT: BIOL ABS. RRM COMPARATIVE UPTAKE, TRANSLOCATION,
AND METABOLISM OF FLORASULAM IN WHEAT AND BROADLEAF WEEDSYMEETING
ABSTRACT WHEAT WEED BROADLEAFED PESTICIDES BIOCHEMISTRY AND
BIOPHYSICS FLORASULAM HERBICIDE UPTAKE TRANSLOCATION METABOLISM
HPLC HIGH PERFORMANCE LIQUID CHROMATOGRAPHY NMR SPECTROSCOPY
ANALYTICAL METHOD LIQUID CHROMATOGRAPHY SPECTROSCOPIC TECHNIQUES:
CB
