JP2011001337A - Simple weeding technique with fatty acid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a green space-managing herbicide having high safety and simplicity in use.SOLUTION: There is provided a weeding technique for green space management comprising preparation of a low-concentration liquid agent by mixing water with pelargonic acid known as a food additive and one or more kinds of synthetic surfactants allowed to be added to foods and selected from glycerol fatty acid esters, sucrose fatty acid esters, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters and polyoxyethylene glycerol fatty acid esters and use of the liquid agent as it is without dilution.

Description

  The present invention relates to a weed control technique around the living environment.

  It is a well-known fact that intermediate fatty acids, especially pelargonic acid (nonanoic acid), are safe and extremely fast compounds with herbicidal activity. In the United States, it is used as a flowering agent for apples and pears, annual weed control for potatoes and peanut fields, or as a herbicide for non-agricultural land (US EPA PC Code 217500). In Japan, a pesticide was registered as a pelargonic acid 52% emulsion (Nippon Tobacco Inc., trade name: Gran Torico) in 1996. After potato planting, pre-emergence treatment, peanut growing season intercostal treatment, and other herbicides for green space management. There is a track record sold as.

Pelargonic acid causes a death reaction only at the contact site of the drug. Accordingly, it is easy to regenerate from a site where adhesion is insufficient, and it is difficult to spray a small amount of high concentration. At the same time, it is difficult to avoid an increase in treatment costs because the amount of active ingredient dropped per area is a few kg per 10a compared to commonly used synthetic herbicides. In order to solve these problems, a technique of mixing a synthetic herbicide or a plant growth regulator that suppresses the growth of regenerating weeds is disclosed.
JP2002-158451 JP 11-335209 A In general, in order to stabilize the effect of agricultural chemicals, it is necessary to uniformly attach the drug to the target site, and surfactants are widely used as auxiliary agents. Surfactants used for herbicides can be mixed with surfactants that affect plants, and techniques for mixing cationic surfactants that damage cells into pelargonic acid are also disclosed. .
US Patent 5106410

Pelargonic acid is a saturated fatty acid having 9 carbon atoms, and its solubility in water is as small as 32 ppm (30 ° C.). Therefore, it is generally used as a high-concentration emulsion dissolved in oil and containing a surfactant. Therefore, when spraying after diluting, the generated fine mist-like water droplets have problems that irritate eyes and mucous membranes and generate unpleasant odors. Ammonium salts that solve these problems and have improved solubility in water are also used in the United States as agricultural chemicals (US EPA PC Code 031802).
US Patent 6608003 The salt of pelargonic acid dissolves easily in water and is less irritating. However, on the other hand, there is a problem that the effect expression is delayed and the herbicidal activity is reduced by neutralization.

In view of the above background, pelargonic acid having low water solubility and low herbicidal activity has been formulated and used as a high-concentration emulsion. The pelargonic acid 52% emulsion in Japan was not widely used due to the effects and price problems, and the pesticide registration expired in 2003.
In addition, in order to avoid inferior effects, solutions using cationic surfactants that mix existing herbicides or damage cells have a value for the safety of pelargonic acid, a food additive. Then, it is thought that it loses.

  In recent years, glyphosate or glufosinate salts as household herbicides are diluted with water and filled in plastic containers. The amount of use is greatly expanding because no one gets dirty and can easily spray pesticides without error. For these products, containers and transportation costs occupy most of the cost, and the proportion of active ingredients related to herbicidal activity is small. That is, the pharmaceutical formulation that is preliminarily diluted and filled in the container can provide a highly safe herbicide for home use without causing a large increase in price even for pelargonic acid with a large amount of active ingredient dropped.

Further, the method of directly spraying the diluted solution from the container is to drop the chemical solution by atmospheric pressure and gravity from a relatively large hole without applying pressure. Therefore, even if pelargonic acid is sprayed directly, there is no generation of mist-like water droplets, and there is an advantage that the mucous membrane or the like is not stimulated. The drop amount can obtain the expected herbicidal effect by treating 50 to 200 ml / m ² without diluting a 1.5 to 5% solution of pelargonic acid.

  In order to dissolve or emulsify an effective amount of pelargonic acid having low water solubility in water, a surfactant is required. The surfactant used in preparing a low-concentration solution of pelargonic acid, which is a food additive, is desired to have the highest possible safety. Synthetic surfactants that have been confirmed to be safe in Japan and are allowed to be added to foods are glycerin fatty acid ester, sucrose fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene glycerin fatty acid ester By mixing one or more of these surfactants with pelargonic acid, it is possible to provide a herbicide that guarantees higher safety.

  A safe and simple herbicidal technique is provided in which pelargonic acid is mixed with water as a food additive in water and sprayed as it is without dilution.

(Pharmaceutical preparation example 1)
Various surfactants, 28% ammonia aqueous solution (product of Wako Pure Chemical Industries, Ltd.), potassium hydroxide (product of Wako Pure Chemical Industries, Ltd.) and water are added to 90% pelargonic acid (product of Merck Co., Ltd.) Prepared. For comparison, 20 g of an emulsion obtained by adding an organic solvent and a surfactant to pelargonic acid was prepared. The formulation and the solution state after 1 hour are shown in Table 1. In addition, the emulsion was diluted 50 times and the state was observed in the same manner as the above solution.
The trade names, general names, and sales company names of the surfactant and organic solvent are shown in Table 10 below.

(Weeding test example 1)
On April 22, 2009, 30 ml of each prescription drug according to Preparation Example 1 and 30 ml of 50-fold dilution solution for mugwort and horsetail with a plant height of 10 to 20 cm in Ami-cho, Inashiki-gun, Ibaraki Was placed in a small sprayer (Canyon HI-SPRAYER) and sprayed on a 50 cm square section. A control drug glufosinate ammonium salt 0.2% solution (Buster solution 0.2, Bayer Crop Science Co., Ltd. product) was also sprayed in the same amount. Table 2 shows the herbicidal effect after 2 days and 15 days later. The evaluation of the herbicidal effect was performed by the survival rate compared to the untreated group. ●: Completely dead. A: 10% or less of all individuals. ○: 11 to 20% of all individuals. □: 21-40% of all individuals. Δ: 41-60% of all individuals. X: 61% or more of all individuals.

(Pharmaceutical preparation example 2)
100g of 90% pelargonic acid plus various surfactants, ammonium hydrogen carbonate (product of Wako Pure Chemical Industries, Ltd.), sodium carbonate (product of Wako Pure Chemical Industries, Ltd.), trisodium phosphate (product of Kishida Chemical Co., Ltd.), and water A liquid was prepared. The formulation and the solution state after 1 hour are shown in Table 3.

(Weeding test example 2)
On April 27, 2009, a preparation of 2 to 20 cm of mugwort and horsetail with a plant height of 10 to 20 cm in Ami-cho, Inashiki-gun, Ibaraki Prefecture, and 30 ml of each drug according to prescription number 2 were placed in a small sprayer. It sprayed on a 50cm square section. The same amount of the control drug glufosinate ammonium salt 0.2% solution was also sprayed. Table 4 shows the herbicidal effect after 3 days and 16 days. Evaluation of the herbicidal effect was performed in the same manner as in Herbicidal Test Example 1.

(Pharmaceutical preparation example 3)
Various surfactants shown in Table 3 below, sodium carbonate, and water were added to 90% pelargonic acid to prepare 100 g of a liquid. The formulation and the solution state after 1 hour are shown in Table 5.

(Weeding test example 3)
On April 30, 2009, 30 ml of wormwood and cedar with a height of 10 to 20 cm in the forest of Ami-cho, Inashiki-gun, Ibaraki Prefecture, and 30 ml of each drug according to prescription number 12 and prescription number 12 were placed in a small sprayer. It sprayed on a 50cm square section. Table 6 shows the herbicidal effect after 1 day and 15 days later. Evaluation of the herbicidal effect was performed in the same manner as in Herbicidal Test Example 1.

(Pharmaceutical preparation example 4)
Various surfactants, urea (product of Wako Pure Chemical Industries, Ltd.), ammonium hydrogen carbonate, and water were added to 90% pelargonic acid to prepare 100 g of a liquid. The formulation and the solution state after 1 hour are shown in Table 7.

(Weeding test example 4)
On May 7, 2009, a small amount of 30 ml of each drug according to Formulation No. 4 and Formula No. 12 and Formula No. 19 was prepared for mugwort and horsetail of 10 to 20 cm in height in the forest of Ami-cho, Inashiki-gun, Ibaraki It put into the sprayer and spread | dispersed to the 50cm square section. Table 8 shows the herbicidal effect after 2 days and 14 days. Evaluation of the herbicidal effect was performed in the same manner as in Herbicidal Test Example 1.

(Weeding test example 5)
May 21, 2009 Pelargonic acid 2.5% (90% Merck's pelargonic acid 2.8%) for mugwort, horsetail, enokorogusa and tsuyugusa, planted below 20 cm in Tsukuba City, Ibaraki Prefecture , Polyoxyethylene sorbitan monolauryl ether (twin # 20) 2%, sorbitan monolaurate 1%, and water-prepared drug using a commercially available spray device (Sumitomo Chemical Horticultural Co., Ltd. grass extermination shower container) A fixed amount was sprayed. A control drug glufosinate ammonium salt 0.2% solution was sprayed at 100 ml / m ² . Performed in 1.5 sq.m. ² repeats in a section. Table 10 shows the average herbicidal effect after 1 day and after 14 days. Evaluation of the herbicidal effect was performed in the same manner as in Herbicidal Test Example 1.

Claims (1)

  A herbicidal solution containing 1.5% to 5% pelargonic acid and sprayed as it is without diluting one or more surfactants mixed with water from among surfactants that can be used as food additives.