4-chloroindole-3-acetic acid for controlling unwanted plants
11606956 · 2023-03-21
Assignee
Inventors
- Pierre Talbot (Rivière-du-Loup, CA)
- Alain Bélanger (Rivière-du-Loup, CA)
- George Kanellos (Rivière-du-Loup, CA)
- Shaun Purcell (Rivière-du-Loup, CA)
- Paul Lefebvre (Rivière-du-Loup, CA)
- Geneviève Roy (Rivière-du-Loup, CA)
- Dominique Lequere (Rivière-du-Loup, CA)
Cpc classification
A01N25/00
HUMAN NECESSITIES
A01N59/08
HUMAN NECESSITIES
A01N47/28
HUMAN NECESSITIES
A01N25/00
HUMAN NECESSITIES
International classification
A01N59/08
HUMAN NECESSITIES
Abstract
The present application relates to compositions comprising 4-chloroindole-3-acetic acid (4Cl-IAA) or an analogue thereof, or a combination of the latter, in the form of a potassium salt, a sodium salt or an amine salt. For example, such compositions can be used used in methods for selectively causing damage or mortality to weed.
Claims
1. A method for selectively causing damage or mortality to weed, said method comprising applying on said weed 4-chloroindole-3-acetic acid (4Cl-IAA) in the form of a potassium salt, a sodium salt or an amine salt, wherein the 4Cl-IAA is applied at a dose greater than or equal to 0.005 g/plant and less than or equal to 0.1 g/plant for a targeted application, wherein selectively causing damage or mortality to weed comprises selectivity for a dicotyledon weed over a monocotyledon species, and wherein the monocotyledon species is selected from grasses.
2. The method of claim 1, wherein said 4Cl-IAA is in the form of an aqueous composition.
3. The method of claim 1, wherein said 4Cl-IAA is in the form of a powdered or granular solid.
4. The method of claim 1, wherein said 4Cl-IAA is in the form of a powdered or granular solid obtained from a solution of 4Cl-IAA, in the form of a potassium salt, a sodium salt or an amine salt, said solution being absorbed or retained on a solid matrix, or obtained from a crystalline form of 4Cl-IAA, in the form of a potassium salt, a sodium salt or an amine salt, mixed with other, more or less active solid inputs.
5. The method of claim 1, wherein the 4Cl-IAA is present in an aqueous composition in a concentration varying from 1.5 g/L to 40 g/L.
6. The method of claim 1, wherein the 4Cl-IAA is used in combination with a chelating agent.
7. The method of claim 6, wherein the chelating agent is chosen from cyclohexanediaminetetraacetic acid (CDTA), ethylenediamine-N, N′-disuccinic acid (EDDS), ethylenediaminetetraacetic acid (EDTA), ethanol diglycine (EDG), hydroxyethylethylenediaminetriacetic (HEDTA), methylglycinediacetic acid, glutamicadiacetic acid, trans-1,2-diaminocyclohexane-N, N, N′, N′tetraacetic acid, diethylenetriaminepentaacetic acid (DTPA), iminodisuccinic acid, the salts thereof, and combinations thereof.
8. The method of claim 6, wherein the chelating agent is chosen from EDDS, EDTA, DTPA, HEDTA, the salts thereof, and combinations thereof.
9. The method of claim 1, wherein the applying is carried out in one or several applications at similar or different doses.
10. The method of claim 1, wherein the 4Cl-IAA is in the form of a potassium salt.
11. The method of claim 1, wherein the 4Cl-IAA is in the form of a sodium salt.
12. The method of claim 1, wherein the 4Cl-IAA is in the form of an amine salt.
13. The method of claim 1, wherein the dicotyledon weed is of a genus selected from the group consisting of Taraxacum, Hieracium, Trifolium, Medicago, Plantago, Arctium, Circium, Leontodon, Potentilla and Tussilago.
14. The method of claim 1, wherein the monocotyledon species is turf.
15. A method of using 4-chloroindole-3-acetic acid (4Cl-IAA), said method comprising contacting 4Cl-IAA in the form of a potassium salt, sodium salt or an amine salt with water, for preparing an aqueous composition effective for selectively causing damage or mortality to weed, wherein the 4Cl-IAA is used at a dose greater than or equal to 0.005 g/plant and less than or equal to 0.1 g/plant for a targeted application, wherein selectively causing damage or mortality to weed comprises selectivity for a dicotyledon weed over a monocotyledon species, and wherein the monocotyledon species is selected from grasses.
16. The method of claim 15, wherein the 4Cl-IAA is further used in combination with a chelating agent.
17. The method of claim 15, wherein the 4Cl-IAA is used in the form of a potassium salt.
18. The method of claim 15, wherein the dicotyledon weed is of a genus selected from the group consisting of Taraxacum, Hieracium, Trifolium, Medicago, Plantago, Arctium, Circium, Leontodon, Potentilla and Tussilago.
19. The method of claim 15, wherein the monocotyledon species is turf.
20. A method for selectively causing damage or mortality to weed, said method comprising applying on said weed 4-chloroindole-3-acetic acid (4Cl-IAA) in the form of a potassium salt, a sodium salt or an amine salt, wherein the 4Cl-IAA is applied at a dose greater than or equal to 0.05 g/m.sup.2 and less than or equal to 1.0 g/m.sup.2 for a spreading application, wherein selectively causing damage or mortality to weed comprises selectivity for a dicotyledon weed over a monocotyledon species, and wherein the monocotyledon species is selected from grasses.
21. The method of claim 20, wherein the dicotyledon weed is of a genus selected from the group consisting of Taraxacum, Hieracium, Trifolium, Medicago, Plantago, Arctium, Circium, Leontodon, Potentilla and Tussilago.
22. The method of claim 20, wherein the monocotyledon species is turf.
23. A method for selectively causing damage or mortality to weed, said method comprising applying on said weed 4-chloroindole-3-acetic acid (4Cl-IAA) in the form of a potassium salt, a sodium salt or an amine salt, wherein the 4Cl-IAA is applied in one or several applications at similar or different doses, wherein selectively causing damage or mortality to weed comprises selectivity for a dicotyledon weed over a monocotyledon species, and wherein the monocotyledon species is selected from grasses.
24. The method of claim 23, wherein the dicotyledon weed is of a genus selected from the group consisting of Taraxacum, Hieracium, Trifolium, Medicago, Plantago, Arctium, Circium, Leontodon, Potentilla and Tussilago.
25. The method of claim 23, wherein the monocotyledon species is turf.
26. A method of using 4-chloroindole-3-acetic acid (4Cl-IAA), said method comprising contacting 4Cl-IAA in the form of a potassium salt, sodium salt or an amine salt with water, for preparing an aqueous composition effective for selectively causing damage or mortality to weed, wherein the 4Cl-IAA is used at a dose greater than or equal to 0.05 g/m.sup.2 and less than or equal to 1.0 g/m.sup.2 for a spreading application, wherein selectively causing damage or mortality to weed comprises selectivity for a dicotyledon weed over a monocotyledon species, and wherein the monocotyledon species is selected from grasses.
27. The method of claim 26, wherein the dicotyledon weed is of a genus selected from the group consisting of Taraxacum, Hieracium, Trifolium, Medicago, Plantago, Arctium, Circium, Leontodon, Potentilla and Tussilago.
28. The method of claim 26, wherein the monocotyledon species is turf.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF THE INVENTION
(16) The present invention consists of a solution of 4Cl-IAA, or an analogue thereof, or a combination of the latter, in acid, salt or ester form, able to selectively eliminate several types of weeds encountered in horticulture and/or agriculture in different situations or conditions. This solution can be used in the form of a more or less viscous liquid. Alternatively, this solution can be absorbed or retained on a solid matrix for use in the form of a powdered or granular solid. In one embodiment, the solution is obtained from water and a potassium salt, a sodium salt or an amine salt such as triethanolamine, ethylenediamine or oligoamines. In another embodiment, the crystalline form of the 4Cl-IAA or an analogue thereof, a combination of the latter, in acid, salt or ester form, can be mixed with other, more or less active solid inputs, to be used in a powdered or granular form
(17) 4Cl-IAA is a natural molecule that shows little or no toxicity for health and the environment, preventing it from being banned from use.
(18) It has been observed that doses of 0.01 to 0.1 g/plant per application, used in a targeted manner on the foliage, were causing gradual blight able to spread over several weeks depending on the growing season, type of weed, age of the plant and climate conditions. Typically, the physiological disruptions caused by the invention are manifested by a more or less pronounced epinasty, wilting and/or curvature of the leaves and/or stem and/or flowers after several hours, blockage of growth after 24 hours, and the appearance of more or less obvious reddish spots and/or chloroses after 3 to 5 days. Preferably, the doses to be applied are between 0.02 and 0.08 g/plant, and ideally between 0.03 and 0.06 g/plant. It is interesting to emphasize that a 4Cl-IAA solution ultimately has control capacities of the same magnitude as those observed with a 2,4-D-based synthetic auxinic herbicide. Using the hypothesis that a dandelion, for example, occupies a surface of 100 cm.sup.2, corresponding to a more or less square zone of 10 cm×10 cm, there would be 100 dandelions on a surface of 1 m.sup.2. If each dandelion receives a dose of 0.01 g, for instance, 1 g is applied over the zone of 1 m.sup.2 completely covered with dandelions. It is thus possible to express the doses previously presented in grams per square meter instead in grams per plant. Following this conversion, the corresponding doses are therefore from 1 to 10 g/m.sup.2 for targeted applications over a surface completely covered with dandelions.
(19) The efficacy of a selective herbicide is based on two main parameters, namely the ability to control weeds combined with the minimum applicable dose and the selectivity of the effect with respect to the desirable plants. This last parameter makes it possible to determine the maximum applicable dose. At doses below 0.01 g/plant, one observes low control capacities and/or excessive variability surrounding this capacity. It should be noted that the control capacity is expressed in the form of a damage rating of the foliage ranging from 1 to 5 and/or a mortality percentage of the targeted plant. The damage rating is useful to assess the user's perception of the efficacy of the product, since it is assigned based on the appearance of the external foliage. The mortality percentage in turn provides information on the ultimate efficacy of the product, since it is computed from the number of plants that have actually died or disappeared after a given length of time. The approval agencies use this last assessment method greatly. As an example, a product allowing a weed mortality rate of 80% will, in some jurisdictions, bear the word “eliminates” on its label, while a product with a rate of 60% will be described as “suppressing.” These nuances may have a significant impact on informed users' choice of herbicide.
(20) For spreading applications, the doses are between 0.1 g/m.sup.2 and 1.0 g/m.sup.2 per application. Preferably, the doses to be applied are between 0.3 and 0.8 g/m.sup.2, and ideally between 0.4 and 0.6 g/m.sup.2. These doses are smaller than the doses determined for targeted applications, which would vary from 1 g/m.sup.2 to 10 g/m.sup.2 if the considered zone was completely covered with dandelions, i.e., 100 dandelions receiving 0.01 and 0.1 g/plant. This smaller quantity of 4Cl-IAA used must be analyzed based on the two parameters selected to describe the efficacy of a selective herbicide, i.e., the control capacity and the selectivity of the effect with respect to the desirable plants. Indeed, the reduced quantity is related to the selectivity aspect, or effect on the turf as an example. With a spreading application, the product is distributed uniformly over the entire treated surface. The turf receives as much product as the weeds, unlike a targeted application, where the majority of the product reaches the weeds. Indeed, with a targeted application, the quantity of product touching the turf most often originates from a drift phenomenon. If the desirable plants, for example the turf, receive the same dose as the weeds, this dose must be reduced to eliminate or minimize the perceived impact on these desirable plants. This decrease in the dose will of course have certain consequences on the weed control capacity, in particular resulting in a slower appearance of visible damage. In the context of a spreading application, this shift may be tolerated, since the user, most often a professional, is in a different perception dynamic from that prevailing in a targeted application context. In the latter case, the user is most often a consumer anxious to see the weed that is inconveniencing him disappear. It is also important to mention that when yellowing of the turf is observable, it decreases and disappears entirely with time, unlike the weed, which move inexorably toward their death, showing the selectivity of the molecule at the established doses. In the case of large-leaved weeds present in the turf, this selectivity will therefore be based not only on morphological differences (carriage of the plant and position of the meristem) responsible for a differential absorption, but also in all likelihood on different metabolic reactions.
(21) Furthermore, it has been observed that the different identified doses must be applied with a solution having concentrations greater than or equal to 1.5 g/L and lower than 40 g/L. Solutions having concentrations below 1.5 g/L create an excessively weak propelling force or excessively low concentration gradient on the surface of the leaf. Such a situation slows the penetration of the product in the leaf, and possibly its subsequent movement in the plant, which results in a lower control capacity that may appear less attractive to some users. At the other extreme, a solution having a concentration above 40 g/L implies application volumes reduced too much by the established doses. As an example, it would be necessary to apply 12.5 mL of product with a concentration of 40 g/L on one square meter for a spreading dose of 0.5 g/m.sup.2, which proves difficult in light of the existing equipment. For a targeted application with a dose of 0.05 g/plant, it would be necessary to use only 1.25 mL on a plant having, by way of illustration, a surface of 100 cm.sup.2, which also proves difficult for an adequate application.
(22) It should also be noted relative to the invention that the dose of product can be applied just once on a given zone, or can be subject to several applications, for both considered types of application. Such flexibility is of interest when dealing with certain weeds that are more troublesome due to their size, for example. In the same vein as discussed above, it may be advisable, as an example, to perform several spreading applications, more or less spaced apart, when the season is drier or further along and the turf is more sensitive. As an illustration, the dose per application used can be in the lower part of the recommended range under such conditions.
(23) It is important to stress that 4Cl-IAA, like other endogenous auxins, is a molecule that moves primarily in the plant by polar transport. This mode of transport is much slower than the nonpolar transport observed with other substances moving in the xylem and the phloem. A rate of 5 to 20 cm/h is discussed for nonpolar transport, compared to a movement of 5 to 20 mm/h for polar transport. In the latter case, the movement is done slowly, but inexorably, from cell to cell, going from the stem to the root. According to the literature (Reemmer and Murphy, 2014, Auxin and its Role in Plant Development, Springer edition, pages 75 to 100), synthetic auxins such as 2,4-D and naphtalene-1-acetic acid (NAA) move more quickly in the plant than IAA and 4Cl-IAA. This situation therefore explains the slower observed response regarding weed control with one of the embodiments of the present invention relative to a synthetic auxinic herbicide, even if, ultimately, the result is comparable. In the case of a product for targeted application against dandelions intended for the consumer market, as an example, this shift in the response may represent a drawback relative to a faster synthetic or conventional auxinic herbicide. To overcome this difficulty, one preferred embodiment of the present invention incorporates a co-ingredient moving less slowly, by nonpolar transport for example, and able to cause quick surface necrosis or more or less permanent visible damage to the foliage and/or the stem. Several action strategies can be used to this end: damage associated with a nutrient overdose, osmotic shock, toxicity related to a chelated or non-chelated metal, and/or any other visible metabolic disruption occurring quickly, for example with another auxin that may be synthetic (for example. 2,4-dichlorophenoxyacetic acid (2,4-D) or 3,6-dichloro-2-methoxybenzoic acid (Dicamba)) or natural (for example, indole-3-acetic acid (IAA), indole-3-butyric acid (IBA), etc). As an example, it is recommended to use concentrations, on a weight basis, from 0.1 to 5% for metals, such as iron and manganese, irrespective of whether they are chelated (HEDTA or EDTA, for example), from 1 to 36% for sodium chloride or manganese chlorate, from 1 to 50%, preferably 5-15%, for urea and from 1 to 20% for fatty acids, such as carboxylic and phosphonic acids. It should be noted that the disruption causing a short-term visible effect does not need to be permanent or fatal for the plant, since the 4Cl-IAA will take over. As an illustration, a solution containing 0.45% of 4Cl-IAA combined with 10% of urea makes it possible to obtain a damage rating of 3.4 after 3 days, whereas a solution of 4Cl-IAA alone shows only a small effect after the same amount of time. It should be noted that after 35 days, both solutions have a maximum rating of 5 for dandelion control. The same phenomenon occurs with spreading applications.
(24) Aside from its efficacy under the described conditions, the invention has other advantages. The 4Cl-IAA molecule can be formulated with various formulation agents in order to better adapt the properties of the finished product to the different encountered application contexts. On the one hand, buffer solutions, preservatives, such as Proxel™, surfactants, such as Tween™, and thickeners can be added alone or in combination, depending on what is needed.
(25) On the other hand, it is possible to use chelating or sequestering agents in order to facilitate penetration of the molecule in the plant. Indeed, it may be desirable to reduce the dose of 4Cl-IAA applied and/or the concentration of this molecule in the finished product in the context, for instance, of a more fragile turf or a given type of weed. The different families of chelating or sequestering agents that may be used are, but are not limited to, carboxylic acids (for example, aminopolycarboxylic acids, aromatic carboxylic acids, aliphatic carboxylic acids), amino acids, hydroxycarboxylic acids, carboxylic ether acids, as well as phosphonic acids. It should be noted that these products can be incorporated into the formulation in acid or salt form.
(26) As an illustration, the addition of hydroxyethylenediaminetriacetic acid (HEDTA) or hydroxy ethylene diamine disuccinic acid (EDDS) made it possible to halve the tested minimum dose without chelating agent for a formulation with or without incorporating a co-ingredient. Indeed, for doses of 0.0075 g per plant, an interesting increase was observed in the damage rating on dandelions (from 3.1 to 4.3), as well as a reduced variability of the observed results expressed in the form of variation coefficient (from 29 to 15%). Likewise, it appears that the chelating agents make it possible to reduce the concentration of 4Cl-IAA in the solution to concentrations as low as 1 g per liter without affecting the desired efficacy. It should also be noted that the product can be sold in concentrated form and diluted upon use or application to comply with the identified doses.
(27) Peroxide deterioration tests demonstrated that 4Cl-IAA offers a certain stability. Indeed, a finished product incorporating the molecule shows stability over two years in storage at room temperature. Interestingly, the literature indicates that the molecule can be catabolized by bacteria from the soil such as Bradyrhizobium japonicum via the same metabolic pathways known for IAA (Jensen J B, Egsgaard H, Van Onckelen H, Jochimsen B U, Catabolism of indole-3-acetic acid and 4- and 5-chloroindole-3-acetic acid in Bradyrhizobium japonicum, 1995, J. Bacteriol. 177 (20): 5762-6).
(28) Lastly, the present invention can also be implemented with an analogue related to the position of the chlorine on the aromatic cycle or with one of the esters, natural or not, such as the methyl ester, for example, of the 4Cl-IAA molecule or one of its analogues. A given product based on one of these different molecules or a combination thereof therefore makes it possible to control a multitude of weeds in the professional or nonprofessional horticulture sector and the agriculture sector.
(29) Although the invention is described using certain preferred embodiments, in particular in the examples, these must not limit the scope of the invention. On the contrary, alternatives, modifications and equivalents are considered, as they may be defined by the present application. The objects, advantages, aspects and other features of the invention will become clearer and will be better understood in light of the non-limiting description of the invention, in particular owing to the figures in the application.
EXAMPLES
(30) The following examples show the efficacy of a new selective herbicide based on the use of the 4Cl-IAA molecule according to certain embodiments of the present invention.
Example 1
(31) Title
(32) Efficacy of 4Cl-IAA on dandelion damage and the impact rating on turf assessed for targeted applications under various conditions.
(33) Methodology
(34) The experiments were conducted according to completely randomized design and randomized complete block design with targeted applications for dandelion control on various turfed terrain.
(35) Treatment: 4Cl-IAA without co-ingredient
(36) Dependent variable: mean damage rating (from 0 to 5) on the dandelions and impact rating (from 0 to 3) on the turf assessed after 7 and 40 days.
(37) The results are shown in
(38) Interpretation
(39) The product showed relatively constant dandelion control efficacy and turf impact despite highly variable weather conditions (mean daily temperature from 4 to 21 degrees Celsius, pluviometry from 12 to 388 mm and hardiness zone from 3B to 5B and season from June to October) and different operators involved in taking data (subjective rating assessment). This is therefore a robust product faced with different usage conditions.
Example 2
(40) Title
(41) Effect of the dose of 4Cl-IAA on dandelion control assessed according to the damage rating for targeted applications.
(42) Methodology
(43) The experiment was conducted using a randomized complete block design. Four repetitions were done for each treatment.
(44) Treatment: 4Cl-IAA without co-ingredient
(45) Dependent variable: mean damage rating (from 0 to 5) with the variation coefficient assessed after 42 days.
(46) The results are shown in
(47) Interpretation
(48) Damage rating of the weed=control (perceived effect)
(49) At doses below 0.01 g/plant, the damage rating decreases, and above all, the variability surrounding the latter increases considerably, which yields a less reliable product.
Example 3
(50) Title
(51) Effect of the dose of 4Cl-IAA on dandelion control assessed using the mortality percentage for targeted applications.
(52) Methodology
(53) The experiment was conducted using a randomized complete block design. Four repetitions were done for each treatment.
(54) Treatment: 4Cl-IAA without co-ingredient
(55) Dependent variable: Mean mortality percentage with the variation coefficient assessed after 42 days.
(56) The results are shown in
(57) Interpretation
(58) Weed mortality percentage=control (final effect)
(59) At doses below 0.01 g/plant, the mortality percentage decreases by about 50% (below the 60% corresponding to the “suppressed” mention on the label) and the variability surrounding this percentage increases greatly, which yields a relatively unreliable product.
Example 4
(60) Title
(61) Effect of the dose of 4Cl-IAA on the selectivity of the product assessed according to the turf impact rating for targeted applications
(62) Methodology
(63) The experiment was conducted using a randomized complete block design. Five repetitions were done for each treatment.
(64) Treatment: 4Cl-IAA without co-ingredient
(65) Dependent variable: Impact rating (from 0 to 3) on the turf assessed after 7 days.
(66) The results are shown in
(67) Interpretation
(68) Turf impact rating=selectivity
(69) At doses below 0.1 g/plant, the turf impact goes from zero to acceptable. Beyond a dose of 0.1 g/plant, the turf impact becomes too visible and the risk of exceeding the acceptable rating increases, more or less quickly depending on the prevailing situation, in particular in terms of the condition of the turf.
Example 5
(70) Title
(71) Effect of the dose of 4Cl-IAA on dandelion and burdock control for targeted applications
(72) Methodology
(73) The experiment was conducted using a randomized complete block design. Five repetitions were done for each treatment.
(74) Treatment: 4Cl-IAA without co-ingredient applied at a dose of 0.015 g/plant with a concentration of 1.9 and 7.5 g/L
(75) Dependent variable: mean damage rating (from 0 to 5)
(76) The results are shown in
(77) Interpretation
(78) Damage rating of the weed=control (perceived effect)
(79) With concentrations below 1.9 g/L, the weed control efficacy is slowed and/or reduced excessively.
Example 6
(80) Title
(81) Effect of urea as co-ingredient of the 4Cl-IAA on dandelion control for targeted applications
(82) Methodology
(83) The experiment was conducted using a randomized complete block design. Four repetitions were done for each treatment.
(84) Treatment: solution of 4Cl-IAA applied at a dose of 0.03 g/plant containing 10% urea as co-ingredient
(85) Dependent variable: mean damage rating (from 0 to 5)
(86) The results are shown in
(87) Interpretation
(88) Damage rating of the weed=control (perceived effect)
(89) The addition of 10% urea as co-ingredient accelerates the dandelion control efficacy perceived by the user, particularly during the first 72 hours. After 30 days, the two formulations come together in terms of efficacy.
Example 7
(90) Title
(91) Effect of iron, manganese, salt and urea as co-ingredient(s) on dandelion control for targeted applications
(92) Methodology
(93) The experiment was conducted using a randomized complete block design. Four repetitions were done for each treatment, except for iron chelate, where three repetitions were done.
(94) Treatment: solutions of 4Cl-IAA applied at doses of 0.02 to 0.03 g/plant containing 10% urea or 6% sodium chloride or 0.24% iron chelate (HEDTA) or 0.1% manganese chelate (HEDTA) as co-ingredient
(95) Dependent variable: mean damage rating (from 0 to 5) assessed after 7 days
(96) The results are shown in
(97) Interpretation
(98) Damage rating of the weed=control (perceived effect)
(99) All three types of co-ingredients caused a pronounced acceleration in the control efficacy perceived by the user.
Example 8
(100) Title
(101) Comparison of the effect of 4Cl-IAA with other auxins on dandelion control for targeted applications
(102) Methodology
(103) The experiment was conducted using a randomized complete block design. Four repetitions were done for each treatment, except for 4Cl-IAA methyl ester, where three repetitions were done.
(104) Treatment: the applied quantities varied from 0.014 to 0.036 g/plant, except for IAA, where the quantity was higher (0.2 g/plant) in light of the information found in the literature on the effect of the latter.
(105) Dependent variable: mean damage rating (from 0 to 5) and mean mortality percentage assessed between 28 and 35 days after application
(106) The results are shown in
(107) Interpretation
(108) Damage rating of the weed=control (perceived effect)
(109) Weed mortality percentage=control (final effect)
(110) The 4Cl-IAA and its methyl ester show control efficacies close to those observed with a 2,4-D-based herbicide. It is possible that the methyl ester of 4Cl-IAA is converted into 4Cl-IAA in the plant. The use of IAA shows an interesting damage rating, but a low mortality percentage for a higher quantity. This last result indicates a metabolization of the molecule by the plant or a weaker action of the molecule on the plant allowing regrowth of the leaves and/or survival of the plant.
Example 9
(111) Title
(112) Effect of a targeted second application on plantain control for different doses of 401-IAA
(113) Methodology
(114) The experiment was conducted using randomized complete block design. Four repetitions were done for each treatment.
(115) Treatment: 4Cl-IAA without co-ingredient at three doses, i.e., 0.015, 0.023 and 0.030 g/plant
(116) Dependent variable: mean mortality percentage
(117) The results are shown in
(118) Interpretation
(119) Weed mortality percentage=control (final effect)
(120) Under certain usage conditions, a second application can provide a pronounced improvement in the control efficacy. Furthermore, it appears that two applications of 0.015 g/plant could be more effective than one application of 0.030 g/plant.
Example 10
(121) Title
(122) Weed species studied and able to be controlled with targeted applications of 4Cl-IAA
(123) Methodology
(124) The experiments were conducted according to completely randomized design and randomized complete block design with targeted applications for weed control on various terrain covered in turf.
(125) Treatment: 4Cl-IAA without co-ingredient with doses varying from 0.022 to 0.036 g/plant
(126) Variables: Observation of a damage rating above 4 and a mortality percentage above 80%, assessed after a period of 21 to 40 days, depending on the species.
(127) TABLE-US-00004 TABLE 4 Foliar morphology of different dicotyledonous weeds. Leaf morphology Common Trichome Cuticle Type of foliar Latin name name density thickness limb Arctium Burdock Strong Weak Whole lappa Circium Thistle Weak Average Whole arvense Hieracium Hawkweed Strong Weak Whole pilosella Leontodon Autumn Strong Average Whole autumnalis hawkbit Medicago Lupulin Strong Weak Segmented lupulina Taraxacum Dandelion Weak Average Whole officinale Plantago sp. Plantain Weak Strong Whole Potentilla Potentilla Average Average Segmented reptans Trifolium Clover Strong Weak Segmented repens Tussilago Coltsfoot Strong Average Whole farfara
(128) Interpretation
(129) Weed damage rating=control (effect perceived)
(130) Weed mortality percentage=control (final effect)
(131) With doses of the same magnitude, 4Cl-IAA makes it possible to control several dicotyledonous weed species having various foliar morphologies that may influence the absorption of a substance. This is therefore a versatile product working with different weed species.
Example 11
(132) Title
(133) Effect of the dose of 4Cl-IAA on dandelion control and selectivity of the product for spreading applications
(134) Methodology
(135) The experiment was conducted using a randomized complete block design. Three repetitions were done for each treatment with surface areas of 0.5 m.sup.2.
(136) Treatment: 4Cl-IAA without co-ingredient with an application rate of 100 mL/m.sup.2
(137) Dependent variable: mean damage rating (from 0 to 5) of the dandelion and mean impact rating (from 0 to 3) on the turf assessed after 50 days
(138) TABLE-US-00005 TABLE 5 Effect of the dose of 4Cl-IAA on dandelion control Dose (g/m.sup.2) 1.2 1.0 0.6 0.3 Dandelion damage rating 3.9 3.8 4.1 3.0 Turf impact rating 2.0 1.7 1.7 0.7
(139) Interpretation
(140) Weed damage rating=control (effect perceived)
(141) Turf impact rating=selectivity
(142) A dose of 4Cl-IAA of 1.2 g/m.sup.2 and above risks affecting the turf excessively, and a dose of 0.3 g/m.sup.2 shows a control efficacy that is still acceptable.
Example 12
(143) Title
(144) Effect over time of the dose on the selectivity of the product and turf regrowth for spreading applications of 401-IAA
(145) Methodology
(146) The experiment was conducted using a completely randomized design with surface areas of 2 m.sup.2 per treatment.
(147) Treatment: 4Cl-IAA without co-ingredient with an application rate of 100 mL/m.sup.2
(148) Dependent variable: impact rating (from 0 to 3) on the turf assessed after 4 and 90 days
(149) TABLE-US-00006 TABLE 6 Effect at 4 or 90 days of an application of 4Cl-IAA Dose (g/m.sup.2) 1.2 1.0 0.9 0.6 0.25 After 4 days 3 2 1 1 0 After 90 days 0 0 0 0 0
(150) Interpretation
(151) Weed damage rating=control (effect perceived)
(152) Even when highly affected, the turf recovers well and becomes green again after 90 days, unlike the weeds, which move inexorably toward their death.
Example 13
(153) Title
(154) Effect of urea as co-ingredient of the 4Cl-IAA on dandelion control for spreading applications at different doses
(155) Methodology
(156) The experiment was conducted using a randomized complete block design. Three repetitions were done for each treatment.
(157) Treatment: 4Cl-IAA with 10% urea and without urea applied with a spreading rate of 100 m L/m.sup.2 at doses of 0.3, 0.6 and 0.9 g/m.sup.2
(158) Dependent variable: mean damage rating (from 0 to 5) of the dandelion assessed after 2 days
(159) The results are shown in
(160) Interpretation
(161) Dandelion damage rating=control
(162) The addition of 10% urea as co-ingredient accelerates the dandelion control efficacy perceived by the user after 48 hours. For all three studied doses, the effect of the urea is substantially the same.
Example 14
(163) Title
(164) Decreased presence of weeds in the turf after one or two spreading applications of 401-IAA
(165) Methodology
(166) The experiment was conducted using a randomized complete block design. Three repetitions were done for each treatment.
(167) Treatment: 4Cl-IAA with a spreading rate of 100 mL/m.sup.2 for an application of 0.6 g/m.sup.2 with 6% urea and two applications of 0.3 g/m.sup.2 with 3% urea separated by one week.
(168) Dependent variable: Percentage of decrease in weeds estimated after 28 days from readings relative to the presence or absence of weeds using an observation grid of 100 points per square meter.
(169) The results are shown in
(170) Interpretation
(171) Weed disappearance=control
(172) Both application strategies yielded decrease percentages above 60% after 28 days for different types of weeds. The strategy based on two applications yielded higher results, i.e., 79% versus 64%. Furthermore, the number of applications affects the species differently and alters the proportions of the different weeds, which may be interesting in certain situations.
(173) Furthermore, although the preferred embodiments of the invention as described include several components and characteristics, not all of these components are necessarily essential to the invention, and they consequently must not be considered restrictively, i.e., must not be considered in such a way as to limit the scope of the present invention. It must be understood, as will be obvious for one skilled in the art, that other appropriate components and geometries and/or other possible cooperations between the latter may be used according to the present invention, without going beyond the scope of the invention.
(174) The description must be interpreted as an illustration of the invention, and must not be considered to limit the claims. The scope of the claims must not be limited by the preferred embodiments illustrated in the examples, but must instead receive the broadest possible interpretation in accordance with the description as a whole.