Note: Descriptions are shown in the official language in which they were submitted.
~ ~2~7~
The recently found phosphinothricine type herbicides of the
formula
3 \
P ~ CH2 - CH2 - CH - COOH
HO NH2
have a good contact activi~y and are well absorbed by leaves, so that they
are suitable for non-selectively combating weeds of all botanic classes. They
are therefore applicable against undesirable plant growth on farming grounds,
industrial areas etc. ~see German Offenlegungsschrift No. 2,717,440).
Herbicides of the phosphinothricine type are effective against
annual as well as perennial weeds and weed grasses. Some economically import-
ant perennial weeds such as quack-grass (Agropyron repens), Bermuda grass
(Cynodon dactylon), perennial cyperaceae and corresponding dicotyledonous weeds,however, are sufficiently combated only with increased herbicide amounts.
Surprisingly, it has now been found that the addition to phosphino-
thricine and its derivatives of certain types of organic and inorganic compoundswhich for themselves have no herbicidal activity produces a pronounced syner-
gistic effect, that lS, considerably increases the herbicidal efficiency againstannual and perennial weeds.
According to one aspect of the present invention there is provided
a herbicidal composition which comprises an amount of:
~ A) a phosphinothricine derivative of the formula
H C O
~:: 3 ~ 11
P - CH - CH - CH - COOH
~; / 2 2
RO NH2
in which R is hydrogen or ~Cl-C4)-alkyl, a salt thereof with an acid or base or
a peptide thereof, in combination with;
--2--
"~
l 162~7~
B~ an inorganic or organic ammonium salt of the formula
R3
R2 _ N - R4 X II
R n
in which Rl to R4, being identical or different, each are hydrogen, ~Cl-C4)-
alkyl or hydroxyethyl, or two of the radicals Rl to R4 together with the nitro-
gen atom form a 3- to 7-membered ring a -CH2 group of which may be replaced by
0, NH or N(Cl-C4)-alkyl; X is the anion of an inorganic or organic mono- or
polybasic acid and n is 1, 2 or 3, or with the free base from which the salt
of the formula II are derived, or with a precursor metabolizing under physiologi-
cal conditions to a compound of the formula II; or
C) an inorganic or organic chelating agent, selected from the group
consisting of polybasic organic acids or their salts, and water-soluble poly-
phosphates of different chain length which are used in the soap and detergent
industry, wherein the weight ratio of components A to B or C is from 4 : 1 to
150, with the proviso that, if R in formula I is hydrogen, the compound B
is not a free base. Preferably, the peptide in component A is phosphinothricyl-
alanyl-alanine.
According to another aspect of the present invention there is pro-
vided a method for combating weeds which comprises applying to the areas infested
by them the above composition in an amount of from 0.125 to 35 kg of active
substance ~component A ~ component B or C) per hectare.
Phosphinothricine and its derivatives have an asymmetric carbon
atom, and thus may be present in the form of racemates or optionally active
enantlomers, the L-enantiomer of which is especially preferred in accordance
wlth the invention.
; A) Due to their amphoteric nature, phosphinothricine and its esters
are able to form salts with inorganic and organic bases and acidsj which salts
-3-
07~
may likewise be used for the compositions of the invention. When using bases,
compounds are formed in which R is cation equivalent. The following cation
equivalents are particularly important: Na , K , 1/2 Ca , lt2 Zn , 1/2 Mg
N~ N~(CH3)4, H2N (CH3)2, H2N ~C2H5)2, NH ~C2H5)3' 3 3 3 3 7
4 9 2 3 7 )2~ H3N CH2CH20H, H2N (CH2CH20H), HN~CH CH OH)
~CH3)3N CH2CH20H, (CH3)2N HCH2CH20H, CH3N H2CH2CH20H, (CH3)2N HC12H25, and the
guanidinium ion.
When using strong bases, the -COOH group is ionized, too, and diso-
dium or dipotassium salts, for example, are obtained in these cases.
1~ For salt formation with acids, any inorganic and organic acids
such as HCl, HBr, H2S04, H3PO4, }INO3 or CH3COOH may be used.
In accordance with the invention, oligopeptides of phosphinothricine
are alternatively suitable as component A, such as phosphinothricyl-alanyl-
alanine which is described in
~ -3a-
1 182~71
- 4 - HOE 80/F 041
Helv. Chim. Acta 55, 224 seq. (1972).
B) The B type compounds are preferably ammonium salts
(R1 to R4 = H), but salts of organic ammonium bases with
any anions (see A) may also be used. Preferred organic
ammonium salts have cations such as enumerated sub A) and
anions such as Cl , Br , S04 , HS04, P03 , Hpo42 , ,
'~2P04, CH3COO , (COO )22 , or SCN .
Compounds which metabolize in the ?lant to form ammo-
nium ions are likewise useful, for example urea, aspartic or
glutamic acid.
Instead of the ammonium salts II, the free bases from
which they are derived, for example triethylamine or piperi-
dine, may be used in combination with phosphinothricine
- esters, salts or peptides.
C) Suit~ble complexing agents of type C are for
example polybasic organic acids such as oxalic, succinic,
tartaric, citric, nitrilotriacetic or ethylenediamine-tetra-
acetic acid (EDTA~ or their salts, furthermore water-soluble
polyphosphates of different chain length (metaphosphates,
triphosphates) which are used in the soap and detergent
industry. Such complexing agents are described for example
in O.A. Neumuller: Rompps Chemielexikon, 7nd. ed. 1972,
pp. 545 and 2768 seq.
The compounds of types B ànd C can be combined with the
A type herbicides either individually, or several of them in
any number may be employed.
The mixing ratio of the individual components in the
combinations of the invention may vary within wide
limits. A synergistic effect is observed at a ratio of
A : B(C) between 4 : 1 and 1 : 150. For practical reasons,
the mixing ratio is chosen in a range of from 2 : 1 to
1 : 50, preferably 1 : 1 to 1 : 10.
The mixtures of the invention may have the form of
ready-to-use formulations, for example wettable powders or
emulsifiable concentrates, which are applied in usual manner
as aqueous dilutions, or as so-called tank mixtures which
are prepared immediately before application by common~ dilu~
tion of the separately formulated components with water.
I lB207~
- 5 - HOE 80/F 041
Alternatively, the herbicides and the synergists may be
separately applied as spray liquors or aqueous solutions;
the sequence of the components being irrelevant.
The application concentration of the A type herbicides
in the mixtures of active substances is generally from 0.10
to 5 kg/ha, that of B and C from 0.025 to 30 kg/ha; that iS3
the total amount of active substance combination is in the
range of .rom about 0.125 to 35 kg/ha.
The compositions o. the invention can be employed in
form of the usual formulations known to the expert skilled
in the art, for example as wettable powders, dusts, granu-
les, emulsifiable concentrates or sprayable solutions, and
contain generally from 2 to 95 weight % of the combinations
of active substances according to the invention.
Wettable powders are formulations which are uniformly
dispersible ln water and which, in addition to the active
compound, and a diluent or inert material, also contain
wetting agents, for example, polyoxyethylated alkylphenols,
alkylsulfonates or alkylphenylsulfonates, and dispersing
agents, for example sodium ligninsulfonate, sodium-dinaph-
thylmethane-disulfonate, or the sodium salt of oleoyl-
methyl-taurir.e.
Emulsifiable concentrates are obtained by dissol~ing
the active ^ompound in an organic solvent, for example,
butanol, cyclohexanone, dimethylformamide, xylene or even
higher-boiling aromatics, and adding an emulsifier, for
example, a polyoxyethylated alklphenol.
In the case the herbicidai compositions, the concen-
trations of the active compounds in the commercial formula-
tions can vary. In wettable powders, the active compoundconcentration (herbicide and synergist) varies, for example,
between about 1u and 95 %, the remainder consisting of one
or more of the above-mentioned formulation additives. In
the case of emulsifiable concentrates, the active compound
concentration is about 10 to 80 %. Dust formulations
usually contain 5 - 20 g of active compound, and sprayable
solutions about 2 - 20 %. In the case of granules, the
active compound content in part depends on whether the
,. .
1 16207~
- 6 - HOR 80/F 041
active compound is in a liquid or solid form and what granu-
- Lating auxiliaries, fillers and the like are used.
If necessary or desired the commercial concentrates
may be diluted prior to application in the usual manner, for
example by means of water in the case of wettable powders
and emulsifiable concentrates. Dust, granules and sprayable
solutions are generally ready for use without further dilu-
tion with inerc materials. The amount of active ingredient
necessary for obtaining th desired result depends on exter-
nal conditions such as temperature, humidity and the like.
The actiYe compounds according to the invention can becombined with other herbicides, fungicides and insecticides.
The following examples illustrate the invention.
i5 E X A M P L E
Seeds of annual weeds and rhizomes of perennial noxious
plants were placed in pots of plastic material filled with
loamy soil, and left in a greenhouse under favorable growth
conditions. After 3 weeks, the plants had formed 3 to 4
leaves, in which stage they were sprayed either with the
herbicide at varying dosage, or with mixtures of herbicide
and synergists; the application concentration being main-
tained at a constant 12 kg/ha. For comparison, further test
plants were treated with a solution of the synergist alone.
In all cases, the amount of liquid corresponded to 600 l/ha.
3 Weeks after the treatment, the degree of damage of
the plants treated was evaluated in comparison with the
~ntreated control.
The results listed in Table 1 show that the synergist
alone did not damage the plants, but in combination with the
test herbiclde considerably increased the herbicidal effect.
In the case of Alopecurus, for example, a herbicide concen-
tration of 0.~ kg/ha yielded an 80 % damage of the plants;
the same degree of damage was attained at a herbicide amount
of 0.15 kg/ha only with the addition of 12 kg/ha of the
synergist.
The improved effect in the perennial weeds Agropyron
(quack-grass), Cyperus (nutsedge) and Cyanodon (Bermuda
6~71
- 7 - HOE 80/E 041
grass) by addition of the synergists was also remarkable.
These are weeds of special economic importance, which are
normally difficult to combat.
Table 1 (Plant damage in %)
.. . . _, . . _ . . . . . . . .. .
Compound Dose AVF ALM SAL LO~S ECG AGR CYE CND
kg AS/ha
Phosphino- 0.6 75 80100 95 90 32 65 55
.. . _ .. .. ... . .. .
thricme hydro- 0.15 32 3270 32 38 - - -
.. . _ . . _ .. ...
chlori~e 0.08 0 0 32 0 11 - - -
(A II)
ammonium 12.0 0 0 0 0 O O O O
_. _ _ . .... ~
sulfate (B I)
A II ~ B I 0.6 ~ 12.0 1OG g5100 100 94 85 85 90
0.15 ~ 12.0 65 8085 70 74 - -
0.08 + 12.0 32 3265 65 38 - ~ ~
.
Abbreviation for Tables 1 to &:
.
AVF = Avena (wild oats) ECG = Echinochloa (barn-
yard grass)
ALM - Alopecurus (annual black- AGR = Agropyron (quack-
grass) grass)
SAL = Setaria (wild millet) CYE = Cyperus (nutsedge)
LOM = Lolium (rye grass) CND = Cynodon (Bermuda
grass3
POA = Poa (meadow grass) SRH = Sorghum
30 SDS = Sida DIS = Digitaria (crabgrass)
AS = Active substance COA = Convolvulus (bind-
weed)
ABT = Abutylon CRS = Chrysanthemum
~; (yellow ox-eye)
E X A M P L E 2
Seeds of Echinochloa crus-galli were sown in pots of
plastic material filled with loamy soil and placed in a
J
1 lB2071
- 8 - HOE 80/F 041
greenhouseO After 3 weeks, in the stage of 3 to 4 leaves,
the plants were sprayed with solutions containing the herbi-
cide alone or in admixture with a synergist in varying do-
sage; the application concentration of the synergist being
3.6 kg/ha in all cases. For comparison, a solution contain-
ing the synergist alone was used. 2 Weeks after treatment
the percent degree of plant damage was evaluated in compari-
son with untreated controls. The results listed in Table 2
show that the synergist alone did not damage the plants, but
in combination with the test herbicide considerably in-
creased the herbicidal effect against Echinochloa crus-galli.
Table 2 damage of Echinochloa (effect i~ %)
_ .. _ . .. _. .. _ _ ... . .. .. .. _ _ . _ . .. .. _ ,
Compound Dose ECG
-- -- _ _
kg a.s./ha
_ . . . . . .. . . , , _ _
ammonium salt of 0.2 ~0
phosp~no~icine _ _ _ 0.1 50
~A lIIj 0 05 40
-- ---------- 0.025 5
amm~nium nitrate
_ _ . . .. . _ _ _ .. . . _
(B II) 3.6 0
~ ITI ~ B ~I 0.2 + 3.6 9~
Q.1 1 3.6 80
0.05 ~ 3.6 ~5
0 025 + 3.6 ~0
E X A M P L E 3
Under the conditions described in Example 1 the plants
listed in Table 3 were grown from seeds in pots of plastic
material and treated in the stage of 3 to 4 leaves with 0.4,
0.2 and 0.1 kg/ha~ respectively, of phosphinothricine mono-
ammonium salt (A III) and phosphinothricine (A I) alone and
in combination with synergists. 3 Weeks after application
the percent degree of plant damage was evaluated in compari-
son with untreated controls. Table 3 shows that the syner-
gists alone in the tested concentrations had no herbicidal
-' ~ 16207~
- 9 - HOE 80/F 041
effect. When 9 however, applying these substances together
with A III and A I, the herbicidal effect of the latter was
considerably increased in all concentrations. This unex-
pected synergism allows reduction of the herbicide concen-
tration to about one half.
Table 3 damage in % of untreated control
. _ .. .. . . _ . .. ... .. . . .
Compound Dose AVF ALM LOM ECG AGR CMD POA
~g/ha
urea
(B III~ 3 . -
B I 6 0 0 0 0 0 0 0
.. . .
Na-EDTA
(C I) 3 0 0 0 0 0 0
phosphinothricLneo.445 40 63 0 0 30
(A I) 0.2 10 30 50 - - 15
A III 0.4 45 30 3594 13 10
0.2 15 5 2390 - - -
0.1 10 0 1510 - - -
. .... _ . .
A III ~ B III 0.4 + 3 4548 6010025 1~ -
0.~ ~ 3 3040 309~
: 0.1 ~ 3 200 2545 - - -
~ . . _ _ _ . . _ . _ .
: A III ~ B I 0.4 + 6 8075 80100 65 50
: 0.2 ~ 6 4565 68100 - ~ -
: : 0.1 ~ 6 2Q20 3399
~ . . _ .. _ . __ _ _
: A IIl ~ C I 0.4 ~ 3 5573 68100 35 20
. 0.2 ~ 3 4538 439g
+ 3 2020 2388 - - -
: A I + B I 0.4 ~ 6 8375 93 65 55 45
0.2 + 6 2555 B8 - ~ 30
E X A M P L E 4
Under the conditions of Example 1, the plants listed in
Table 4 were grown and sprayed in the 3 to 4 leaf stage
either with herbicide or synergists alone or in combination
with each other. 3 Weeks after the application, the damage
.. ,~................................... .
62û7~
- 10 - HOE 80/F 041
was evaluated. The results are listed in Table 4.
In admixture with phosphinothricine ammonium salt
~A III), the synergists produced a pronounced damage of the
weeds even at very low herbicide doses, while alone they had
no or little phytotoxic effect .
Table 4 (damage in %)
Compound Dose CYE SDS ECG SRH DIS
kg AS/ha
-
B I 6.0 0 0 0 0 0
_. . _ _.. . . . ... . .
ammonium chloride
(~ IV) 4.8 0 0 0 0 0
C I 3.0 0 0 5 0 0
, . . ..
~otassium triphosphate .~
3) 3 (C II~: 3.0 0 0 5 0 0
A III 0.4 30
0.2 10 98 25 40 70
0.1 - 70 13 8 ~5
A III + B I0.4 ~ 6 70
- 0~2 ~ 6 5~ 100 g0 ~ 99
0.1 + 6 - 97 58 48 _ 88
IV0.4 ~ 4.8 55
0.2 ~ 4.8 50 100 70 70 98
_0.1 ~ 4.8 - 98 30 35 68
A III ~ C I0.4 + 3.0 60 - - ~
0.2 i 3.0 50 100 90 83 80
0.1 ~ 3.0 - 90 68 55 ~5
.
:~: A III + C II 0.4 + 3.0 60 - - - ~-
0.~ + 3.0 35 100 80 80 100
O.1 + 3.0 - 80 60 48 88
E X A M P L E 5
: ~ Under the conditions of Example 1 the plants listed in
Table 5 were grown and sprayed in the stage of 3 to 4 leaves
either with different phosphinothricine salts and ammonium
sulfate, respectively, alone or in combination with each
other. The ammonium sulfate dosage corresponded to 6 kg/ha,
....
0 7 i
- 71 - HOE 80/F 041
while the phosphinothricine salts were applied in varying
doses. The water amount corresponded to 400 liters/ha.
Three weelcs after application the damage was evaluated. The
results are listed in Table 5. They show that ammonium
sulfate alone had no herbicidal efficiency; however, in
combination with the alkali and alkaline earth metal salt
and ammonium salt of phosphinothricine the herbicidal effi-
ciency of the latter against mono- and dicotyledonous weed
species was considerably increased. Without addition of
ammonium sulfate two or even four times the amount of
phosphinothricine derivative was necessary in order to
attain the same herbicidal effect.
Table 5(damage in %)
Compound Dose AGR LOM CRS COA
(kg AS/ha)
_ _
ammonium sulfate 6.0 0 0 0 0
(B I)
_
calcium salt of 0.8 75 75
phosphinothr-cine 0.4 43 47
(A IV) 0.2 33 30 53
0.1 37
. _
A IY + B Io.8 + 6.0 95 g2
0.4 + 6.0 87 63
0.2 + 6.0 70 43 90
0.1 + ~.0 73
monopotassium 0.8 78 47
salt of phosphi- 0.4 47 33
nothricine (A V) 0.2 28 25 60
0.1 27
A V + B I0.8 + 6.0 93 85
0.4 + 6.0 75 68
0.2 + 6.0 57 l~3 97
0.1 + 6.0 67
1 162071
- 12 - HOE 80/F 041
Table 5 (contd.) (damage in %)
Compound Dose AGR LOM CRS COA
(kg AS/ha)
.
dipotassium 0.8 60 57
salt of phosphi- 0.4 43 37
nothricine (A VI) 0.2 30 27 47
0.1 37
. . .
A VI + B I 0.8 + 5.0 94 83
0.4 + 6.0 75 63
0.2 + 6.0 53 4398
O.~ + 6.0 50
monosodium salt 0.8 7767
of phosphinothri- 0.4 50 43 85
cine (A VII) 0.2 33 3 43
0.1 23
A VII + B I0.8 + 6.0 91 80
.4 + 6.0 75 65100
0.2 ~ 6.0 63 43100
0.1 + 6.o ~o
ammonium salt 0.8 87 68
of phosphino- 0.4 73 4398 53
:thricine (A III) 0.2 . 43 30 l~O 33
O.~ 20 27
A III + B Io.8 + 6.0 96 93
0.4 + 6.0 82 73 100 95
0.2 + 6.o 75 43 100 70
0.1 + 6.0 53 47
:
E X A M P L E 6
In combating perennial weeds, suppression of resprout-
ing from underground plant organs (rhizomes, root-stocks) is
particularly important. In a test on quack-grass ~Agropy-
ron) the influence of addition of ammonium sulfate (4 kg/ha)
to phosphinothricine ammonium salt on the long-time effect-
., . ~ .
~ 1~20~1- 13 - OE 80/F 041
iveness of this herbicide ~as examined.
Quack-grass plants were grown under greenhouse condi-
tions in buckets of plastic material filled with sandy loam,
and in the 5 to 6 leaf stage were sprayed with varying doses
of phosphinothricine ammonium salt (A III) alone and in com-
bination with 4 kg/ha of ammonium sulfate (B I) (water
corresp. to 400 l/ha). After a residence time of 4 weeks in
the greenhouse the overground parts of the treated and un-
treated plants were cut off and the recipients were placed
for a further 7 weeks in the greenhouse. Thereaf~er, the
leaves which had sprouted anew were cut off, dried at
100C, and the dry mass of the leaves was determined.
The dry leaf mass per recipient of treated test plants was
compared with that of untreated controls. The results are
l~stad in Table 6.
Addition of ammonium sulfate to all doses of active
substance resulted in increased suppression of resprouting
while ammonium sulfate alone had no effect at all. The
results demonstrate that in the case of perennial plants
ammonium sulfate obviously increases the systemic effect of
phosphinothricine and thus prolongs the lasting effect of
this herbicide.
Table 6 Resprouting of quack-grass 11 weeks after herbi-
cide treatment
(resprouted leaf mass of treated plants in percent
relative to leaf mass of untreated controls)
Product Dose leaf mass
(kg AS/ha) (% control)
-
A III 2.0 16
1.0 48
0.5 81
_
A III I B I2.0 + 4.0 0.5
.0 ~ 4.~ 22
0.5 + 4.0 31
.
.
207 1
- '14 - HOE 80/F 041
A ~l ~ L ~ ~
According to the method of Example 1, plants were grown
and sprayed in the 3 to 4 leaf stage with solutions of the
compounds indicated in Tables 7 and 8. The water amount
correspGnded to 400 l/ha (with synergists B V, B VI, B VII)
and 200 l/ha (with B VIII).
4 Weeks after application the damage was evaluated.
As Tables 7 and 8 demonstrate, the ethanolamine salts and
piperidine generally improved the herbicidal action of
phosphinothricine ammonium salt. In combination with the
synergists about one half of the amount of A III required
when using the herbicide alone was sufficient to achieve the
same degree of activity. When used alone, the synergists
had no herbicidal activity.
t5 Table 7 (plant damage in ~)
Compound ~ose LOM ABT IPP
(kg AS/ha)
Monoethanol-
ammonium acetate 1.0 0 0 O
(B V)
Diethanolammo-
nium acetate1.0 0 0 0
(B VI)
Triethanolammo~
nium acetate1.0 0 0 0
(B VII)
~
ammonium salt 0.8 66 61
of phosphinthri- 0.4 20 86 50
cine (A IIT)0.2 3 58 25
O.t - 6
-
A III + B V0.8 + 100 84 - 85
0,4 + 1.0 43 99 80
0.2 + 1.0 9 90 28
0.1 ~ 1.0 - 65
A III + B VIo.8 + 1.0 76 - 92
0.4 + 1.0 53 100 77
0.2 + 1.0 18 99 30
0.1 + 1.0 - 73
`` 11 162071
- 15 HOE 80/F_041
Table 7 (contd.) (plant damage in %)
Compound Dose LOM ABT IPP
(kg AS~ha-)
A III + B VIIo.8 ~ 1.0 76 - 93
0.4 + 1.0 48 98 70
0.2 + 1.0 20 70 30
0.1 + 1.0 - 60
:
Table 8 (p'ant damage in %)
Compound Dose ALM LOM CRS
(kg AS/ha)
Piperidine 2~0 0 0 0
(B VIII)
; ~ ammonium salt 0.8 65 55 100
~: of phosphino- 0.4 30 40 98
: thri~ine tA III) 0.2 25 25 85
A III + B VIII0.8 ~ 1.0 70 70 100
:: ; 0.4 + 1.0 45 45 100
0.2 + 1.0 40 40 95
:
~ -
