Abstrict An adjuvant composition for use with a herbicide, crop desiccant,
or defoliant consisting essentially of an ethyl ester of a fatty
acid with an unsaturation level of at least 40% and a non-ionic
ionic emulsifier.
Claims We claim:
1. An adjuvant composition consisting essentially of
(i) an ethyl ester of a fatty acid wherein the ethyl ester has
a level of unsaturation of at least 40% by weight; and
(ii) a non-ionic emulsifier.
2. A composition according to claim 1 wherein the ethyl ester comprises
at least 50% by weight of the total composition.
3. A composition according to claim 1 wherein the non-ionic emulsifier
is a combination of two or more non-ionic emulsifiers.
4. A composition according to claim 1 wherein the non-ionic emulsifier
is a polyethyleneglycol (PEG) ester of fatty acids.
5. A composition according to claim 4 wherein the non-ionic emulsifier
is a polyethyleneglycol (PEG) with a molecular weight range of 200-600
esterified with either one or two moles of unsaturated fatty acids.
6. A composition according to claim 1 wherein the non-ionic emulsifier
is of the alkylarylethoxylate type.
7. A composition according to claim 6 wherein the alkylarylethoxylate
is octyl-, nonyl- or dodecylphenol with 3 to 13 moles of ethylene
oxide.
8. A composition according to claim 1 wherein the non-ionic emulsifier
is a combination of an alkylarylethoxylate and a polyethyleneglycol
(PEG) ester of unsaturated fatty acids.
9. A composition according to claim 8 wherein the non-ionic emulsifier
is ethoxylated nonylphenol with 9 moles of ethylene oxide and PEG
400 di ester of unsaturated fatty acids in the ratio 1:2 by weight.
10. A composition according to claim 9 wherein the unsaturated
fatty acids are based on oleine.
11. A composition according to claim 1 wherein the non-ionic emulsifier
is ethoxylated soy-amine base.
12. A composition according to claim 11 wherein the non-ionic emulsifier
has 15 mole ethoxylation.
13. A composition according to claim 1 wherein the non-ionic emulsifier
is of the fatty alcohol ethoxylate type.
14. A composition according to claim 13 wherein the non-ionic emulsifier
has 6 mole ethoxylated on the 12 carbon fatty alcohol.
15. A herbicide composition consisting essentially of:
(i) a herbicide; and
(ii) an amount of an adjuvant composition according to claim 1
which is at least an equal weight of the active level of the herbicide.
16. A crop desiccant composition consisting essentially of:
(i) a crop desiccant; and
(ii) an amount of an adjuvant composition according to claim 1
which is at least an equal weight of the active level of the desiccant.
17. A defoliant composition consisting essentially of:
(i) a defoliant; and
(ii) an amount of an adjuvant composition according to claim 1
which is at least an equal weight of the active level of the defoliant.
18. An agricultural chemical composition comprising:
(i) an agricultural chemical; and
(ii) an amount of an adjuvant composition according to claim 1
which is at least an equal weight of the active level of the agricultural
chemical.
Description This application has been filed under 35 USC 371 from international
application PCT/AU 94/00229 filed May 5 1994.
FIELD OF THE INVENTION
This invention relates to compositions that are used as adjuvants
to facilitate the effectiveness of herbicides, crop desiccants and
defoliants. More particularly such compositions have proved most
effective against post-emergent weeds during the growing of corn
and soyabean crops, the desiccation of potato and alfalfa foliage
and the defoliation of cotton leaves.
BACKGROUND OF THE INVENTION
To maximise crop yields it has become essential to eliminate competing
growths to allow the specific crops to grow unhindered. To this
end the chemical industry has developed a range of herbicides to
combat almost every weed. Similarly to facilitate mechanical harvesting
it has been found necessary to either desiccate the foliage of potatoes
and alfalfa or defoliate the cotton leaves before the cotton is
plucked.
The man on the land knows however that no herbicide gives a complete
strike rate so a burgeoning sub-industry has developed by which
the efficacy of herbicides can be improved. Many names have been
used to describe such compounds including "suffactants",
"spreaders", "crop oil concentrates" and "spray
adjuvants".
To overcome the problem in general for the industry and in particular
for its own herbicides the BASF organisation patented systems in
1989 (U.S. Pat. No. 4834908 "Antagonism Defeating Crop Oil
Concentrates" and Australian Patent 625194 "Adjuvants
for use with Crop Protection Agents"). These systems are based
on a concentrate comprising in essence 20-90% of a fatty acid ester,
4-40% of an anionic surfactant selected from the partial sulphate
and phosphate esters of ethoxylates and from 7-20% of a fatty acid.
A 100 parts of this blend is added to 140 parts of a hydrocarbon.
In the field, the system has been by-passed by the use of the simple
methyl fatty esters emulsified with suffactants.
Another approach has been disclosed in an article entitled "Small
Grass and Grass Weed Response to BAS-514 with Adjuvants" (Manthey
et al) in Volume 4 Issue 2 of Weed Technology. The use of methyl,
ethyl and butyl estefified sunflower oil is discussed as adjuvants
for BAS-514. This study showed enhancing of BAS-514 by their use.
There was no noted significant difference in efficacy between methyl,
ethyl and butyl esters.
It is recognised that even these products are not optimising the
efficacy of the herbicides.
To facilitate the gathering of potatoes and alfalfa seed, current
practice is to desiccate the growing plants' foliage before harvest.
Certain cationic materials are recommended with products such as
DES-I-CATE and DIQUAT HERBICIDE - HA being well known on the field.
It has also been found that their effectiveness may be enhanced
by use of adjuvants such as AD-IT which is based on emulsified methyl
oleate.
Similar to the current adjuvants for herbicides neither the total
effectiveness, nor the rate of the desiccation is completely satisfactory
for the farmer.
While the mechanical harvesting of crops such as cotton, tomatoes
and beans has lowered production costs, it has also created new
problems. In the case of cotton, mechanical harvesting has created
perplexing problems at gins and textile mills. Such mechanically
harvested cotton absorbs moisture from the spindles of the harvester
and contains considerably more than the normal 5 to 15 percent of
trash present in hand-picked cotton. Particularly bothersome is
leaf material which is one of the most difficult types of trash
to remove. This additional moisture and trash in mechanically harvested
cotton frequently complicates ginning operations and raises the
costs of textile manufacturing by requiring additional steps in
cleaning the cotton at the mill.
Recent efforts have been directed toward the development of various
chemical treatments for the crop plant in an effort to overcome
the objectionable attributes of mechanically harvested cotton. For
example, processes have been suggested in recent years which have
as their objective to provide increased yields of the desired crop
and/or to inhibit rank growth. Such processes have been effective
in some respects. However, some of the prior art methods require
the use of expensive surfactants in order to obtain satisfactory
application of the chemical product to the plant. Other prior art
methods produce an insufficient increase in the crop yield and/or
decreases in rank growth for economic utilisation.
As the answer to this need, a plant growth regulator and its method
of use were patented in 1984 "Plant Growth Regulator and Method
for the Use Thereof" (U.S. Pat. No. 4439224). Whilst significant
improvement was achieved, decreased trash limits continue to be
set by the mills demanding further improvements in the level of
defoliation. |