JP2916201B2 - How to reduce the phytotoxicity of plant growth regulators - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial application field> The present invention reduces or avoids the undesirable harmful effects of 2-chloroethyltrimethylammonium chloride (hereinafter abbreviated as chlormequat) on cultivated plants as a plant growth regulator. It is intended to do so.

<Prior art> Chlorme coat is mainly used as a growth regulator for field crops such as wheat, potatoes, tomatoes, cotton, pepper, and ornamental plants such as hibiscus, azalea, carnation, oleander, nobotan, geranium, begonia, poinsettia, and roses. It is used for the purpose of suppressing the growth of stalks and increasing the resistance to poor environments. There are two methods of use: absorption from the root by soil irrigation and absorption from the foliage by foliar application.When foliar application is performed, the type of plant, the growth history of the plant body, and weather conditions before and after application In some cases, chlorosis may occur in the leaves to be sprayed depending on the mixing with other herbicides, insecticides, and fungicides, or the concentration of the spraying, and it is required to pay close attention to the spraying. (References: Hokkaido Agriculture Department, “Crop Pest Control Standards. Herbicide Use Standards. Plant Growth Regulator Use Standards”, 1990 edition) <Problems to be Solved by the Invention> As described above, chlormequat is used for plant growth control. Although it is necessary to pay close attention to the use of chlorosis in crops to prevent chlorosis, the factors involved in the development of chlorosis are not fully understood and In some cases, the spraying is unavoidable under the conditions, and the weather conditions after the spraying may fluctuate. In some cases, chlorosis has been observed, and the problem to date has not been solved.

In addition, there are cultivated plants (for example, Trolo-mallow, pertussis, etc.) that are highly necessary to suppress stem elongation but are difficult to use chloromequat because chlorosis is likely to occur. There is a long-awaited need for an invention of a method that achieves a high effect.

<Means for Solving the Problems> The present inventors have found that phosphoric acid and various phosphates are useful in solving the above-described problems, and any one or two of these phosphoric acids and various phosphates are useful. The simultaneous use of a mixture of more than one species (hereinafter abbreviated as "phosphoric acid, etc.") and chlormequat at a predetermined ratio or in close proximity to each other enables the generation of chlorosis without impairing the original plant growth regulating action. The present inventors have found that an effect of reducing or avoiding the above can be obtained, and completed the present invention.

The component constituting "phosphoric acid or the like" according to the present invention may be, as phosphoric acid, orthophosphoric acid, metaphosphoric acid, pyrophosphoric acid, etc., and as phosphate, orthophosphate, metaphosphate, triphosphate, It is a diphosphate. Orthophosphates include primary, secondary, and tertiary salts.
Metals or basic groups include potassium, sodium,
Calcium, magnesium, iron and ammonium groups are included, and double salts thereof are also included.

In using these “phosphoric acid and the like” for the purpose of reducing the phytotoxicity of chlormequat to crops, various methods and techniques can be used as described below. That is, (1) Chlormecoat and “phosphoric acid or the like” are mixed at a predetermined ratio, and if necessary, an agricultural chemical adjuvant is added. , Flowables, emulsions and the like.

(2) A method of using chlorme coat as a mixed diluent obtained by simultaneously mixing "phosphoric acid or the like" with a chlorme coat spray liquid when spraying the crop on a crop.

(3) A few days before spraying chlorme coat on crops,
Alternatively, a method in which “phosphoric acid or the like” is used alone or at a different time even after several days, or as a diluent mixed with other agricultural chemicals or liquid fertilizers. In this case, the spraying interval is preferably 1 to 3 days.

(4) Liquid fertilizers, water-soluble solid fertilizers, trace element fertilizers, and plant growth containing phosphates that have a fertilizer effect on crops such as ammonium dibasic phosphate, monobasic calcium phosphate, and monobasic potassium phosphate A method in which a regulator, a yield-enhancing agent, etc. are continuously sprayed simultaneously with or close to chlormecoat. By this method, it is possible to avoid the risk of chemical injury due to chlorme coat, and to promote the growth of crops by top-fertilizing effect or the like, and to obtain effects such as improvement in quality and increase in yield.

The dropped amount of “phosphoric acid or the like” according to the present invention is 1 to 50 g per are as P ₂ O ₅ , and the mixing ratio with chlormequat is 1:10 to 10: 1, preferably 1 to 3 in molar ratio. Three to one. The amount of the drug to be dropped is variable depending on the type of crop, the growth stage of the crop, the amount of sprayed water, the interval of spraying, the weather, and the like.

<Example> Next, in an actual test example, an excellent phytotoxicity-reducing effect of “phosphoric acid or the like” is shown. All the treatment amounts of “phosphoric acid and the like” are expressed in terms of P ₂ O ₅ in terms of the amount of drug dropped per are.

Test Example 1 Application to Spring Seed Wheat “Phosphoric acid etc.” (drug P) and chlorme coat (drug C) were used alone or in a prescribed manner for spring sowed wheat (cultivar: Haruhikari) grown up to the 4th leaf stage in a glass room. The mixture was mixed in a ratio to give a water amount of 10 per are and sprayed on the foliage. Thereafter, the growth was continued in a glass room, and after 10 days, the degree of phytotoxicity (chlorosis) was evaluated according to the following grade. 14
One day later, the height of the wheat was measured, the ratio of the plant to the height of the untreated plant was calculated, and the elongation inhibitory effect was evaluated. The average temperature during the implementation period was 22 ° C, the average maximum temperature was 28 ° C, and the average minimum temperature was 16 ° C.

Grade of phytotoxicity 0: harmless 2: slight phytotoxicity 4: small phytotoxicity 6: moderate phytotoxicity 8: severe phytotoxicity 10: complete withering Test Example 2 Application to Tomato A tomato (variety is Fukuju No. 2) is grown in a glass room until about 4 leaf stage, and a predetermined amount of orthophosphoric acid (drug P) is mixed with chlormequat (drug C) equivalent to 23 g per are. The diluted solution was sprayed with foliage at a water volume of 10 per are, the degree of phytotoxicity (chlorosis) was measured 7 days later, and the height of the plant was measured 7 days later, and evaluated in the same manner as in Test Example 1.

Test Example 3 Application to Tomato (Part 2) Tomato (variety: Shin-Sapporo) is grown in a glass room until about the 5th leaf stage, and chlorme coat (drug C) alone or “phosphoric acid or the like” or urea (drug P, etc.) ) And sprayed on the foliage. Further, orthophosphoric acid was sprayed in the vicinity 3 days before, 1 day, 1 day, or 3 days after the treatment with chlormequat. Thereafter, the plants were grown indoors and examined for the degree of phytotoxicity (chlorosis) 7 days after spraying chlormecoat, the chlorophyll content 16 days later, and the plant height and aboveground weight 25 days later. The investigation method was the same as in Test Example 1, except for the chlorophyll content using a commercially available chlorophyll tester (CT-101, manufactured by Fuji Heavy Industries Ltd.).
The second and third leaflets of the fourth compound leaf were measured on the basis of the light transmittance, and the ratio to the untreated leaf was calculated.
The application date of chlorme coat was November 16 in all test plots, and about 5000 lx of night supplemental lighting was performed for 4 days after application. The average temperature during the implementation period was 22 ° C.

<Effects of the Invention> The present invention makes it possible to avoid the possibility of causing potential phytotoxicity (chlorosis) on crops without impairing the original growth regulating action of chlormequat which is a plant growth regulator, The following effects are obtained.

It has become possible to use it under high-temperature, high-light, multi-light and other climatic conditions that easily cause chlorosis. This is shown in Test Example 3.

Chlorme coat can be used even for cultivated plants that are liable to cause chlorosis, and the application range of chlorme coat can be expanded.

For conventionally used cultivated plants, it is possible to increase the amount of the dropped drug, and the stability of the growth regulating effect is increased.

By the fertilizing effect of phosphoric acid or the like, it is possible to expect a growth promoting effect, a quality improving effect, and a yield increasing effect as well as a plant growth regulating effect.

Continuation of the front page (56) References JP-A-61-106504 (JP, A) JP-A-1-143803 (JP, A) JP-A-60-115501 (JP, A) (58) Fields studied (Int .Cl. ⁶ , DB name) A01N 33/12 A01N 59/26 A01N 25/32

Claims (2)

(57) [Claims] 1. A method for reducing the harm of 2-chloroethyltrimethylammonium chloride, which comprises treating 2-chloroethyltrimethylammonium chloride and phosphoric acid simultaneously or continuously in close proximity. 2. The method according to claim 1, wherein the phosphoric acid is orthophosphoric acid, metaphosphoric acid, pyrophosphoric acid or a salt thereof.