N-(BENZENESULFONYL)THIOCARBAMATES - HERBICIDAL ANTIDOTES

ANTIDOTES DES HERBICIDES A BASE DE N- (BENZENESULFONYL)THIOCARBAMATES

English Abstract

PR-4621A
N-(BENZENESULFONYL) THIOCARBAMATES - HERBICIDAL ANTIDOTES
Abstract of the Disclosure
N-(substituted and unsubstituted benzene-
sulfonyl) thiocarbamates as new compositions of
matter useful as active herbicidal antidotes to
protect various crops from injury when used with
a thiocarbamate herbicide; improved herbicidal
compositions and utility of said compositions
employing N-benzenesulfonyl thiocarbamates having
the formula
<IMG>
wherein X is hydrogen, methyl, chloro, bromo , or
methoxy; n is an interger 1 to 3, inclusive; R1 is
hydrogen or methyl; and R2 is alkyl having from 1
to 4 carbon atoms, inclusive, N-(p-chlorobenzenesulfonyl)
carbamoyl-thiomethyl, benzyl or 4-chlorophenyl;
provided that when X is hydrogen and R1 is methyl,
the R2 is other than ethyl.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A herbicidal composition comprising a thiocarbamate
herbicide and an antidotally effective amount of a compound
corresponding to the formula
<IMG>
in which X is hydrogen, methyl, chloro, bromo, or methoxy;
n is an interger of 1 to 3; R1 is hydrogen or methyl; and
R2 is alkyl having from 1 to 4 carbon atoms, inclusive,
N-(p-chlorobenzene sulfonyl) carbamoyl-thiomethyl benzyl or
4-chlorophenyl; provided that when X is methyl, then R2 is
other than alkyl and when X is hydrogen and R1 is methyl,
then R2 is other than ethyl; said compound being antidotally
active with said thiocarbamate herbicide.
2. The herbicidal composition according to Claim 1
in which X is para-methyl, R1 is hydrogen and R2 is alkyl.
3. The herbicidal composition according to Claim 2
in which R2 is ethyl.
4. The herbicidal composition according to Claim 1
in which X is hydrogen, R1 is hydrogen and R2 is alkyl.
5. The herbicidal composition according to Claim 4
in which R2 is ethyl.
6. The herbicidal composition according to Claim 1
in which X is para-chloro, R1 is hydrogen and R2 is alkyl.
7. The herbicidal composition according to Claim 6
in which R2 is ethyl.
8. The herbicidal composition according to Claim 6
in which R2 is isopropyl.
17

9. The herbicidal composition according to Claim 1
in which X is para-chloro, R1 is hydrogen and R2 is benzyl.
10. The herbicidal composition according to Claim 1
in which X is para-bromo, R1 is hydrogen and R2 is alkyl.
11. The herbicidal composition according to Claim 10
in which R2 is ethyl.
12. The method of protecting soybean crops from injury,
said injury due to the thiocarbamate herbicide S-n-propyl
di-n-propylthiocarbamate, comprising application to the soil
in which said crop is to be planted and grown, a non-phytotoxic
antidotally effective amount of a compound corresponding to
the formula
<IMG>
in which X is hydrogen, methyl, chloro, bromo, or methoxy,
n is an interger of 1 to 3; R1 is hydrogen or methyl; and R2
is alkyl having from 1 to 4 carbon atoms, inclusive,
N-(p-chlorobenzene sulfonyl) carbamoyl-thiomethyl, benzyl or
4-chlorophenyl; provided that when X is methyl, then R2 is
other than alkyl and when X is hydrogen and R1 is methyl, then
R2 is other than ethyl.
13. The method according to Claim 12 in which X is
methyl, R1 is hydrogen and R2 is alkyl.
14. The method according to Claim 13 in which R2 is
ethyl.
15. The method according to Claim 12 in which X is
hydrogen, R1 is hydrogen and R2 is alkyl.
16. The method according to Claim 15 in which R2 is
ethyl.
18

17. The method according to Claim 12 in which X is para-
chloro, R1 is hydrogen and R2 is alkyl.
18 The method according to Claim 17 in which R2 is
ethyl.
19. The method according to Claim 17 in which R2 is
isopropyl.
20. The method according to Claim 12 in which X is
para-chloro, R1 is hydrogen and R2 is benzyl.
21. The method according to Claim 12 in which X is
para-bromo, R1 is hydrogen and R2 is alkyl.
22. The method according to Claim 21 in which R2 is
ethyl.
23. The herbicidal composition as set forth in Claim
1 wherein said thiocarbamate herbicide is selected from the
group S-n-propyl N,N-di-n-propyl thiocarbamate, S-ethyl di-
propyl thiocarbamate, and S-ethyl cyclohexylethyl thiocarbamate.
24. The method of protecting a crop from injury, said
injury due to a thiocarbamate herbicide selected from the group
S-n-propyl N,N-di-n-propyl thiocarbamate, S-ethyl dipropyl
thiocarbamate, and S-ethyl dipropyl thiocarbamate and S-ethyl
cyclohexylethyl thiocarbamate; comprising application to the soil
in which an herbicidally effective amount of said thiocarbamate
is used, a non-phytotoxic amount of a compound corresponding
to the formula
<IMG>
19

in which X is hydrogen, methyl, chloro, bromo, or methoxy;
n is an interger of 1 to 3; R1 is hydrogen or methyl; and
R2 is alkyl having from 1 to 4 carbon atoms; inclusive,
N-(p-chlorobenzene sulfonyl) carbamoyl-thiomethyl), benzyl or
4-chlorophenyl; provided that when X is methyl, then R2 is
other than alkyl, and when X is hydrogen and R1 is methyl,
then R2 is other than ethyl; said compound being antidotally
active with said thiocarbamate herbicide.

Description

~110081
Background of the Invention
~ hile many herbicides are immediately toxic to a large
number of weed pests, it is known that the effect of many herbi-
c~des upon important plant cultivations is either non-selective
or not adequately selective. Thus, many herbicides damage not
only the weeds to be controlled but, to a greater or lesser
extent, the desirable cultivated plants as well. This holds true
for many herbicidal compounds which have been commercially suc-
cessful and are commercially available. These herbicides include
t~pes such as triazines, urea derivatives, halogenated acetani-
lldes, carbamates, thiocarbamates and the like. Some examples
of these compounds are described in U.S. Patents No. 2,913,327,
3,037,853, 3,175,897, 3,185,720, 3,198,786 and 3,582,314.
The side effect of in~ury to a cultivated crop by
various herbicides i8 particularl~ inconvenient and unfortunate.
When used in the recommended amounts in the soil to control
broadleaf weeds and grasses, serious malformstion or stunting of
the crop plants sometimes result. This abnormal growth in the
crop plants results in loss of crop y~eld. The search cont~nues
for good selective herbicides.
Previous attempts are described to overcome th~s
problem. The treatment of the crop ~eed with certain "hormonal"
antagoni~t~c agent3 prior to planting is described; see U.S.
Patents 3,131,5a9 and 3,564,768. ~he protect~e agents, as

11~0081
well as the herbicide in these prior processes are largely
8pecific to certain cultivated plant species or in the nature
of the antagonistic agents. The prior antagonistic agents have
not been notably successful. The aforementioned patents speci-
fically exemplify and describe the treatment of seeds employing
compounds of a different chemical class, not suggestive of the
present invention.
The literature describes the preparation of certain
N-(benzenesulfonyl) thiocarbamates for which no utility is dis-
closed. The reference, Hirooka et al., NiPpon Ka~aku Zasshi:
1970, 91(3) 270(5), CA 73:14369w (1970), relates to the synthesis
and reactions of bis-[N-(phe~ylsulfonyl)-formimidoyl]disulfides.
From certain;reactions of an appropriate disulfide with hydrogen
peroxide, there is obtained N-(phenylsulfonyl)methyl thiolcarba-
mates. ~urther, there i~ reference to certain alkyl p-toluene-
~ulfonylthiocarbamates used in pharmacological e~aluat~ons.
These latter compounds are by Xriesel, D.C. et al., J. Pharm Sci.,
968, 57(10), 1791-3.
Description of the Invention
It h~s been discovered that cultivated crop plants ca~
be protected against injury by thiocarbamate-type herbicides,
alonP or in mixtures or combination with other compounds. Further,
as an a~ternative effect, the tolerance of growing plants, re
particularly soybeans, to the ~locarbamate herbicides, re par-
tlcularly S-n-propyl N,N-di-n-propylthiocarbamate, can be
increased su~stantially by adding to the soil compound of the
type N-(s~bstituted and unsubstituted benzenesulfonyl) thiocar-
bæmate wh~ch is an effect~ve antidote w~th sa~d thiocarbamate
herbicide, s ld compound corresponding to the following formula

11~Q08~
n ~ _ N _C ~R2
wherein X is hydrogen, methyl, chloro, bromo or methoxy; n is
an interger from 1 to 3, inclusive, Rl is hydrogen or methyl;
and R2 is alkyl having from 1 to 4 carbon atoms, inclusive,
methylthio-p-chlorobenzenesulfonyl carbamate, benzyl or
4-chlorophenyl; provided that when X is hydrogen and R~ iS
methyl, then R2 is other than ethyl.
As a preferred embodiment of the present invention, is
a two part herbicide system comprising (1) a first part con~
sisting of at least one thiocarbamate herbicide and (2) a
second part consisting of at least one compound having the
formula
X
n ~ ~ SR
wherein X iS hydrogen, methyl, chloro, bromo, or methoxy; n is
an interger from 1 to 3 inclusive, Rl is hydrogen or methyl;
and R2 is alkyl having from 1 to 4 carbon atoms, inclusive,
N-(p-chlorobenzenesulfonyl) carbamoyl-thiomethyl), benzyl or
4-chlorophenyl; provided that when X is hydrogen and Rl is
methyl, then R2 is other than ethyl; said compound being anti-
dotally active with said thiocarbamate herbicide.
Certain of the compounds disclosed herein are
considered new compositions of matter and correspond to the
following formula
-4-

111~Q8~
n
~3
wherein X is hydrogen, methyl, chloro, bromo or methoxy; n is
an interger from 1 to 3, inclusive, Rl is hydrogen or methyl;
and R2 is alkyl having from 2 to 4 carbon atoms, inclusive,
N-(p-chlorobenzenesulfonyl) carbamoly-thiomethyl, benzyl or
4-chlorophenyl; provided that when X is methyl, then R2 is
other than alkyl and provided that when X is hydrogen and R
is methyl, then R2 is other than ethyl.
In the above descriptions,the following embodiment is
intended for the various alkyl substituent groups. As
exemplary of the alkyl portion wïthin the preferred embodiment
are the following: Methyl, ethyl, n-propyl, isopropyl, n-butyl,
sec.-butyl, isobutyl, and tert.-butyl. Whereas n can be an
interger from 1 to 3, inclusive, preferably n is 3 when X is
methyl; and n is a para-substitution of the X moiety.
As an alternative mode of action, the compounds of this
invention may interfere with the normal herbicidal action of
the thiocarbamate-type and other herbicides to render them
selective in their action. Whichever mode of action is present
the corresponding beneficial and desirable effect is the
continued herbicidal effect of the thiocarbamate with the
accompan~ing decreased herbicidal effect on desired crop
species. This advantage and utility will become more appar~nt
hereinafter.
Therefore, the terms "herbicide antidote" or "anti-
dotal amount", is meant to describe that effect which tends to
counteract the normal injurious herbicidal response that the
herbicide might otherwise produce. Whether it is to be termed
a remedy, interferant,protectant, or the like, will depend upon
the exact
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1110081
mode of action. The mode of action is varied, but the effect,
which is desirable, is the result of the method of treating the
soil in which a crop is planted. Hitherto, there have been no
systems which have been satisfactory for this purpose.
The compounds of this invention represented by the
above formulas can be prepared by several different procedures
depending upon the starting materials.
The appropriate intermediate, arylsulfon$mide, was
reacted with an alkyl chlorothiolformate in the presence of a
hydrogen chloride acceptor to prepare the desired com~ound.
Work-up and purification procedure3 involved standard methods
of extraction, distillation or crystallization. In st instan-
ces, character;ization of the structure was by infrared spectroscopy,
nuclear magnetic resonance or mass spectroscopy, as well as
physical constants.
The compounds of the present invention and their pre-
paration are re particularly lllustrated by the following
examples. Follo~Hngthe examples of preparation is a table of
compounds wh ch are prepared according to the procedures des-
cribed herein. Compou~ number~ have been assigned to them and
are used for ~dentification throughout the balance of the
specification.
E~XAMPIE
Preparatlon of N-(P-methoxvbe~zenesulfonYl~-ethYl thiolcarbamate.
p-Methoxy~enzenesulfonamide (11.7 g., 0.64 le),
potas~ium carbon~te (21.5 g., 0.156 mole), and ethyl chlorothiol-
formate (8.5 g., 0.068 mole) were refl~ed in 80 ml. of acetone
for eight hours. The cooled mlxture was poured into 350 ml.
water snd the solution flltered through Celite and extracted
with benzene to r~move any unreacted chlorothiolfonmate. It
--6--

lllQQ81
was then acidified with hydrochloric acid ~pH about 2) with cool-
ing. The mixture was extracted with benzene and the extract
washed with water and dried over magnesium sulfate. Removal of
the solvent left the product as a very viscous oil. There was
obtained 8.4 g. (48~ theory) of the title compound, n30 1.5502.
EXAMPLE II
Preparation of N-~p-chlorobenzenesulfonyl~-eth~l thiolcarbamate.
p-Chlorobenzenesulfonamide (12.0 g., 0.063 mole),
potassium carbonate (21,5 g., 0.156 mole), and ethyl chlorothiol-
formate (8.5 g., 0.068 mole) were refluxed in 75 ml. of acetone
for six hours. The work-up was as in Example I. The crude
product was triturated with hexane and dried. There was obtained
12.4 g. (70% of theory) of the title compound, m.p. 93-95C. The
structure was confirmed by infrared, nuclear magnetic resonasce,
and mass spectroscopy.
EXAMP~E III
Preparation of N-(benzenesulfon~l)-ethvl th~olcarbamate.
8enzenesulfonamide (39.3 g., 0.25 le~, and potassium
carbonate (90 g., 0.65 mole) were placed in 300 ml. of acetone
and ethyl chlorothiolformate (41 g., 0.33 l~) added over several
hours. The m~xture was s~irred one hour at room temperature,
then refluxed 12 hours. It was cooled, poured into one 1. of
water and acidified wit~ 100 ml. hydrochloric acid. The product
was extracted with 250 ml. benzene and the extract dried over
magnesium sulfate. It was f~ltered and the solvent removed.
Pentsne (100 ml.) was added, whereupon the product cry3tallized.
It wa~ filtered, washed wlth 50 ml. pentane, and dried at 50C.
There was obtained 58 g. (95~ of theory~ of the title com~ound,
m.p. 100-103C. Analys~s: N, calculated, 5.72; found, 5.59;
Analys~s: S, ca~culatedj 26 ~ found, 2S.24.
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111~081
EXAMPLE IV
Preparation of N-(p-chlorobenzenesulfonyl)-p-chlorophenyl thiol-
carbamate.
-
p-Chlorobenzenesulfonamide (19.1 g., 0.1 mole), potas-
sium carbonate (30 g., 0.22 le), and p-chlorophenyl chloro-
thiolformate (22 g , 0.11 mDle) in 150 ml. acetone were refluxed
and stirred for 10.5 hours. The cooled mixture was poured into
one l~ter water and acidified with acetic acid. The precipitate
was filtered, washed with water and dried. There was obtained
20 g. (55.5% of theory) of the title compound, m.p. 129-132C.
Analysis: N, calculated, 3.85; found, 4.83
Analysis: S, calculated, 17.67; found, 17.37.
The ~olLowing is a table of the compounds which are
prepared according to the aforementioned procedures. Compound
numbers have been assigned to them and are used for identification
throughout the balance of the specification.
TABLE I
~R2
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1110(~81
m.p. c.
COMPOUND R R or 30
NUMBER n x 1 2 nD
1 1 para-CH3 H C2H5 104-110
2 1 H H C2H5 100-10~
3 1 para-Cl H 4-Cl-0 129-132
4 1 ~ara-Cl CH3 C2H5 1.5643
1 para-Cl H C2H5 g3-95
6 1 para-Br H C2H5 102-107
7 1 Para-Cl H n-C3H7 94-96
8 1 para-Cl H i C3~7 77-83
9 1 ~ -OCH3 H C2H5 1.5502
1 para-Cl H CH20 94-96
11 3 2,4,6-CH3 H C2H5 105-108
12 ~ Para-Cl ~ -CH2sc(O)~ (O2)-0-Cl(p) 238-239 dec.
The herbicide indicated in the tables and e~sewhere are
used at rates which produce effective contr~l of undesirable
vegetation. The range of rates employed herein produce represen-
tative results within the recommended amounts set forth by the
supplier. Therefore, the weed control in each instance is com-
mercially acceptable within the desired or recommended am~unt.
It i~ clear that the class of herbicidal agents des-
cribed and lllustrated herein is characterized as an effective
herbicide exhibiting such activity. The degree of this herbi-
cldal activity varies among specific compounds and among c~mbi-
nat~ons of specif~c compou~ds within the class. Similsrly, the
degree of activlty to some extent varies Emong the species of
plants to which ~ spe~ific herbicidal compound or comb~nation may
be applled. Thus, select~on of a specific herbicidal compound or
c~mbination to control unde~irable plant species readily may be
made. Within ~he present invention, the prevention of inJury to
a de~ired crop specie~ in~e presenee of a spec~fic compo~nd or
comb~natio~ m~y be achie~ed. The beneficial pLant species which
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1110081
can be protected by this method is not intended to be limited by
the specific crops employed in the e2amples.
The herbicidal compounds employed in the utility of this
invention are active herbicides of a general type. That is, the
members of the classes are herbicidally effective against a wide
range of plant species with no discr~mination between desirable
and undesirable species. The method of controlling vegetation
comprises applying an herbicidally effective amount of the herein
described herbicidal compounds to the area or plant locus where
control is desired. The compositions as set forth in this inven-
tion include those wherein the preferred active thiocarbamate
herbicidal compound is preferably S-n-propyl N,N-di-n-propyl
thiocarbEmate.,
A~ herb~cide as used herein means a compound which con-
trols or modifies the growth of vegetation or plants. Such con-
trolling or difying efects include all deviations from natural
development; for example, k~lling, retardat~on, defoliation, desic-
cation, regulation, ~tunting, tillering, stimulation, dwarfing
and the like. By "plants", it is meant germinant seed~, emerging
seedlings and established vegetation including the roots and above-
ground portions.
Eval~aCio~ ~r~cedores
Flats to be used for growing the crops a~d weed spec~es
were filled with loamy sand soil. Stock solutions of the herbi-
oide ~nd e ch candidate antidote were prepared as foll~ws:
A. Herbicide - S-n-propyl N,N-di-n-propyl
thiocarbamate - VERMAM ~ 6E - 1560 mg. of VERN~M 6E
was diluted in 250 ml. of water so that 5 ml. applied
to a flat is equi~alent to 6 lb/A per flat (based)
- 10

~ 08 1
on the surface area of a flat).
B. Antidote - of each candidate 78 mg. was
dissolved in 20 ml. of acetone with 1% Tween 20
(polyoxyethylene sorbitan nolaurate) so that
5 ml. when applied by pre-plant incorporation
techni~ue (PPI) ~s equal to 5 lb/A per flat.
The herbicide and antidotes were applied to the soil
together as a tank mix employing pre-plant incorporation tech-
nique. To prepare the combined tank mix, 5 ml. of the VERNAM Q
stock solution and 5 ml. of each of the antidote stock solutions
were admixed, followed by incorporation into the soil from the
flats during incorporation in a rotary mixer.
One row each of the following weeds and crop was seeded
into the treated soll in the flats:
Watergrass (Echinochloa crus~alli);
Foxtail (Sataria viridis), and
Soybeans (GlYcine max)
The ~lats were placed on greenhouse benches where
temperatures were maintained between 70-90F. The soil was
watered by sprinkling to Rssure good plant growth. Injury ratings
were taken 2 and 4 weeks after the application was made. Indi-
viâual flats treated with the herbicide alon~ were included to
provide a basis for determining the æmount of injury reduction
provided by the herbicide antidotes.
The following table includes results as percent protec-
tion for the crop according to the procedures discussed above.
The percent protection is determined by a ~om~arison with flats
not treated with the c~ndidate ant~dotes of this invention.

081
TABLE II
Application Method : Pre-plant Incorporation - PPI (Tank Mix)
Crop Species : Soybeans (GlYcine max~
Weed Species : Foxtail (S~taria viridis)
Watergras ~ crus~alli)
* - % injury
** ~ % protection
__________..______________________________________________________
PPI (6 1b/A~ (Tank Mix)
CO~OUND
NUMBER SoYbeans Watergrass Foxtail
VERNAM 6 lb/A 40* 100* 100*
_________________________________________________________________
1** , 37.5 0 0
2 37.5 0 0
3 25 0 0
4 25 0 0
0 0
6 25 0 0
7 25 0 0
8 5~ 0 0
9 25 0 0
~Qa 75 0 0
11 33 o o
~2 50 0 0
$ ~ Pre-plant incorporatlo~ of VERNAM~ and antidote applied
~epurately to soil prior fo i~corporation.
-1~-

1~10~1
The thiocarbamate herbicide S-ethyl cyclohexylethyl
thiocarbamate and compound number 6 when applied to the soil to-
gether as a tank mix employing pre-plant incorporation technique,
exhibited 50 percent protection to grain sorghum (milo) planted
in the treated soil. That is, the injury to emerging grain sorg-
hum plants was decreased by at least 50 percent when grown in
soil treated with a tank mix of compound number 6 and S-ethyl
cyclohexylethyl thiocarbamate. This is compared to grain sorghum
(milo) planted in soil containing a treatment of only the
thiocarbamate herbicide.
Various other varieties of legumes were tes~ed for
antidote activity in conjunctlon with a representat~ve thiocarba-
mate herbicide and a N-(benzenesulfonyl) thiocarbamate. Legumes
are plants that have a symbiotic relationship with nitrogen fix-
ing organisms. For example, soybeans, varieties of phaeolus
vulgarius, peanuts, alfalfa, cloves, peas and the l~ke.
The antidote candidate from the above list of N-(ben-
zenesulfonyl) thiocarbamates com~ound number 5 was used at the
rates of 1 and 2 lb/A. The stock solution used consisted of 39
mg. dissolved in 25 ml. of acetone, such that 2.5 ml~ is
equivalent to 1 lb/A when applied pre-plant incorporated. The
representative thiocarb~mate herbicide was EPTC, S-ethyl N,N-
dipropyl thiocarbamate. The herbicide stock solution was made
up by dissolving 1560 mg. of EPTC 6E in 2~0 ml. water, ~uch that
5 ml. of solution was equivalent to 6 l~/A when pre-plant
incorporated in the soil.
~ avy beans and pinto beans were evaluated ln this test.
Also pre~ent in the planted flats were the weed spec~es, water-
grass and fox ail. The results were rated at two and four weeks
after treatment and seeding. After two weeks EPTC at 6 lb/A with
1 lb/A and 2 lb/A compound number 5 present injured only ~0
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1110081
percent of the navy beans and 0 percent of the pinto bean plants.
After four weeks at 1 lb/A navy bean plants were protected 23
percent and pinto bean plants were protected 40 percent. At
2 lb/A after four weeks navy beans were protected 23 percent
and pinto beans 20 percent. The watergrass and foxtail weed
species were completely (100 percent) controlled four weeks after
treatment with the antidote and herbicide.
Seed Treatment Test
Small flats were filled with Felton loamy sand soil.
Soil incorporated herbicides were applied at this time. The soil
from each flat was placed into a five-gallon cement mixer where
the soil was mixed as the herbicides were applied using a pre-
determined amount of a stock solution containing 780 mg. of
approximately 75 percent active ingredient to 125 ml. of water.
Five ml. of stock solution was applied to the ssll in a volu-
metric pipet. Five ml. of stock solution contained an equiYalent
of herbicide which equals to ~ix pounds per acre when applied to
the soil in the flats. After the herbicide incorporation, the
soil was placed back into the flats.
Flats of herbicide-treated and untreated soil were then
ready to be planted. A pint sEmple of soil was removed from each
flat and placed next to each flat for later use ~n covering up
the seeds. The soil was leveled and rows one-half inch deep were
made for planting seeds. Alternating rows of treated and un-
treated crop seeds were sown. In each test, soybean (G1YC~ne
max) seeds ~ere planted in each row. Rows were approximately
one ~nd one-half inches apart in the flat. Seed~ were treated
by preparing a stock solution by dissolving 2$0 mg. of the anti-
dote compound in 2.5 ml. of acetone, then using 0.5 ml. of the
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1 llQ~8 1
stock solution to treat 10 g. of soybean seed equivalent to 0.5
percent w/w. Antidote compounds can also be applied as liquid
slurries and powders or dusts. In some cases, acetone is used to
dissolve powdered or solid compounds so they could be more
effectively applied to the seeds.
After the flats were seeded, they were covered with the
one pint of soil which had been removed just prior to planting.
Flats were placed on greenhouse benches were temperatures ranged
from 70-90F. Flats were watered by sprinkling as needed to assure
good plant growth. Percent control ratings were taken four weeks
after the treatments were applied.
In each test, the herbicide was applied alone, in com-
bination with t,he seed protec~ant, and the seed protectant was
applied alone to check for phytotoxoclty. The untreated ad;acent
row was employed to observe any beneficial lateral movement of the
antidote compound through the soil. The degree of the effect was
noted by compari~on with the ccntrol.
In this seed treatment test with the herbicide S-n-propyl
N,N-di-n-propyl thiocarbamate, compound number 5 exhib~ted 50 per-
cent protection to the treated soybean seeds. That is, the inj~ry
was reduced by at least 50 percent to the emerging soybea~ plants
grown rom seed treated with compound number 5 compared to un-
treated seed grown in soll containing the thiocarbamate herbicide.
The compounds and compositions of this invention were
employed in effective herbicidal compositions com~rising the anti^
dote and a representative thiocarbamate herbicide as descrlbed
hereinabove. The herbicidal composit~ons were tested in the
foll~wing m~nner
The ~ompositions of the present invention for the pro-
tection of culti~ated crop pLants comprlse an act$ve herbicidal
compound and an antido~e therefor ~elec~ed from the above-described
com~ounds. The compositlons of herb~cide and ant~doee can be
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111()081
prepared by conventional methods through the thorough mixing and
grinding of the active herbicide agents and the antidote with
su~table carriers and/or other distribution media, possibly ~ith
the addition of dispersion agents or solvents.
The antidote compounds and compositions of the present
invention can be used in any convenient form. Thus, the antidote
com~ounds can be formulated into emNlsifiable liquids, emulsifiable
concentrates, liquid, wettable powder, powders, granular or any
other convenient form. In its preferred form, a non-phytotoxic
quantity of an herbicidal antidote compound is admixed with a
selected herbicide and incorporated into the soil prior to or
after planting the seed It is to be understood, however, that
the herbicides can be incorporated into the soil and thereafter
the antidote compound can be incorporated into the 80il. Moreover,
the crop seed itself can be treated with a non-phytotoxic quRntity
of the compound and planted into the soil which has been treated
with herbicides, or untreated with the herbicide and su~sequently
treated with the herbicide. The addition of the antidote com-
pound does not affect the herbicidal acti~ity of the herbicides
The amount of antidote compound present can range bet-
ween about 0.001 to about 30 parts by weight of antidote compound
described herein per each part by weight of herbicide. The exact
~mount of antidote compound will usually be determined on
economic ratios for ehe most effective ~mount usable. It is
understood tkat a non-phytGtoxic quantity of antidote compound
will be employed in the herbicidal com~ositions described herein.
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