JPS63264405A - Male sterilization agent for plant - Google Patents

Abstract

PURPOSE:To obtain a male sterilization agent capable of inducing almost perfect male sterility without causing undesirable side effects to plant, by using a specific cinnoline derivative as active component. CONSTITUTION:The objective agent contains a compound of formula I [X is OH, O<->M<+>, OR<1> or NR<2>R<3>; M<+> is alkali or alkaline earth metal cation or group of formula II (R<4>-R<6> are H, alkyl, alkenyl, benzyl, phenyl, etc.); R<1> is alkyl, alkenyl, alkynyl, alkoxyalkyl, phenyl, benzyl, etc.; R<2> and R<3> are H, alkyl, alkenyl, cycloalkyl, (substituted)phenyl, etc.; Y is F, Cl, trihalomethyl or alkoxy; A<1> is haloalkyl; A<2> is H or halogen], e.g. ethyl 1-(4- trifluoromethoxyphenyl)-1,4-dihydro-4-oxo-5-fluorocinn-oline-3-carboxy late. The male sterilization agent is harmless to pistil and a first filial generation seed can be easily obtained by cross pollination.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a male sterility agent for plants containing a cinnoline derivative as an active ingredient.

Prior Art> It is known from JP-A-61-249972 that certain cinnoline derivatives can be used as chemical hybridizing agents.

<Problems to be Solved by the Invention> However, these compounds have disadvantages, such as those with strong potency having strong chemical toxicity, and those with weak drug toxicity having low efficacy, and cannot be said to be satisfactory.

In recent years, there has been a lot of talk about the food crisis, and is it increasing? j3 E
4. The first generation plants are known to have many superior traits such as higher yields than their parent varieties due to their vigorous growth. In order to obtain first-generation hybrid seeds, it is necessary to prevent self-pollination of the female parent, and for this purpose, the pistil of the female parent must be removed.

Conventionally, this emasculation process was very labor-intensive, and since highly self-pollinating grains such as rice and wheat have pistils and four stamens within small galls, this was done manually to create the first generation of hybrids. It was almost impossible to produce seeds. There are also other methods, such as the use of cytoplasmic male sterility,
This also has problems, such as the fact that it takes a long time to grow, and therefore there is a need for a simple and reliable method to induce male sterility without losing the female's ability to pollinate.

Means for Solving the Problems In view of the above situation, the present inventors have made extensive studies and found that the general formula [I] Represents a lower alkoxyalkyl group, a halo-lower alkyl group, a cycloalkyl group, a beyunozyl group or a phenyl group. R2 and R8 are each the same or different, and are a hydrogen atom, a lower alkyl group, a lower alkenyl group, a lower alkynyl group, a cycloalkyl group,
It represents a benzyl group or hydroxyalkyl group which may be substituted with up to two methyl groups at the α-position, or a phenyl group which may be substituted with the same or different lower alkyl group or halogen atom. RlR and R6 are the same or different and each represents a hydrogen atom, a lower alkyl group, a lower alkenyl group, a lower alkynyl group, a cycloalkyl group, a benzyl group or a phenyl group. Y represents a fluorine atom, a chlorine atom, a trihalomethyl group or a lower alkoxy group. A1 represents a halo-lower alkyl group, and A represents a hydrogen atom or a halogen atom. ] The present invention has been completed by discovering that male sterility can be induced very easily and efficiently by treating plants with the cinnoline derivative shown in reached.

The cinnoline derivative represented by the general formula [1] can be produced, for example, by the following method.

(2) Cinnoline-3-carboxylic acid ester derivative El -11 in the general formula [11, where X represents -OR1] [wherein R', Y1A' and A2 have the same meanings as above. ] represents the general formula [1] [wherein RlY, A and A represent the same meanings as above. Q represents a halogen atom.

However, when Y represents a fluorine atom, Q represents a fluorine atom. ] It can be produced by reacting the hydrazone derivative represented by the following with a dehydrohalogenating agent.

The reaction is usually carried out without a solvent or in a solvent in the presence of a dehydrohalogenating agent, and the reaction temperature ranges from θ to 150°C.
The range of one reaction time is 10 minutes to 20 hours, and the amount of reagents used in the reaction is 1 to 10 equivalents of the dehydrohalogenating agent per 1 part of the hydrazone derivative [I].

In order to carry out the reaction more effectively, quaternary ammonium salts and crown ethers may be added.

Examples of solvents include aliphatic hydrocarbons such as hexane, heptane, linegroin, and petroleum ether, aromatic hydrocarbons such as benzene, toluene, and xylene, and halogenated hydrocarbons such as chloroform, carbon tetrachloride, dichloroethane, chlorobenzene, and dichlorobenzene. Hydrocarbons, diethyl ether, diisopropyl ether, dioxane,
Ethers such as tetrahydrofuran and diethylene glycol dimethyl ether, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, isophorone, and cyclohexanone, esters such as ethyl formate, ethyl acetate, butyl acetate, diethyl carbonate, nitro^ such as nitroethane and nitrobenzene, acetonitrile , nitriles such as isobutyronitrile, pyridine, triethylamine1. Tertiary amines such as N,N-diethylaniline, tributylamine and N-methylmorpholine, acid amides such as formamide, N,N-dimethylformamide and acetamide, sulfur compounds such as dimethylsulfoxide and sulfolane, water, etc. , and mixtures thereof.

Examples of dehydrohalogenating agents include organic bases such as pyridine, triethylamine, and N,N-diethylaniline; chain bases such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, and sodium hydride; and sodium methoxide. , alkali metal alkoxides such as sodium ethoxide, and the like.

Examples of quaternary ammonium salts include benzyltriethylammonium chloride and tetrabutylammonium chloride.

Examples of crown ethers include dibenzo-18
-Crown-6 etc. can be mentioned.

After completion of the reaction, the reaction solution is subjected to usual post-treatments such as extraction of crystals generated by addition of water, organic solvent extraction, and concentration, and if necessary, purified by operations such as chromatography and recrystallization. The cinnoline-3-carboxylic acid ester derivative [1-13] can be obtained.

(2) A cinnoline-8-carboxylic acid derivative El-2) A'0 in which X represents -OH in the general formula CI] [wherein Y, A' and A2 have the same meanings as above. ] is a cinnoline-8-carboxylic acid ester derivative (1-
It can be produced by hydrolyzing 1).

The reaction is usually carried out with water or water with methanol, ethanol, isopropanol, diethylene glycol, alcohols such as glycerin, ketones such as acetone, tetrahydrofuran, ethers such as dioxane, nitriles such as acetonitrile, formamide, N,N - Carry out in a mixed solvent with acid amides such as dimethylformamide and sulfur compounds such as dimethylsulfoxide.

Usually, the reaction is carried out by adding an acid or an alkali, and the amount thereof is 1 to 100 equivalents per equivalent of cinnoline derivative [I-1]. The reaction temperature is 20°C to 100'C,
It can be completed in 80 minutes to 10 hours. Examples of the acid include hydrochloric acid, sulfuric acid, nitric acid, etc., and examples of the alkali include sodium hydroxide, potassium hydroxide, etc.

After the reaction is completed, neutralization is performed with hydrochloric acid, sulfuric acid, nitric acid, formic acid, acetic acid, etc. when an alkali is used. Post-treatment after the reaction is completed, for example, if crystals are formed, they are removed,
If no crystals are formed, the desired cinnoline derivative El-2] can be obtained by operations such as organic solvent extraction and concentration.

■ In the general formula [I], cinnoline-8-carboxylic acid derivative [1-8] O in which X represents 10M' [wherein, Y, A' and A2 represent the same meanings as above, and M' is Represents an alkali metal or alkaline earth metal. ] represents the cinnoline-3-carboxylic acid derivative [1-2] and the general formula M·OH[il [wherein M' represents the same meaning as above]. ] It can be produced by reacting with a metal hydroxide represented by:

Examples of metal hydroxides include lithium hydroxide, sodium hydroxide, potassium hydroxide, and calcium hydroxide.

The reaction is usually carried out in water, and 1 equivalent of the cinnoline-8-carboxylic acid derivative N-2 is mixed with 0 of the metal hydroxide.
．． 7 to 1 equivalent. Reaction is from 0°C to 50″0.5 minutes
It can be completed in 5 hours. After the reaction is completed, the desired cinnoline-3-carboxylate derivative [1-8
) to obtain a cinnoline-8-carboxylic acid amine salt derivative [
1-4] [In the formula, R4, R6, R6, Y, A' and A2 represent the same meanings as above. ] is the cinnoline-8-carboxylic acid derivative N-2] and the general formula [IV] [wherein R4, R5 and R6 represent the same meanings as above. ] It can be produced by reacting with the amine shown below.

The reaction is usually carried out without a solvent or in a solvent, and the reaction temperature ranges from θ°C to 100°C, and the reaction time ranges from 5 minutes to 80°C.
time, and the amount of reagents used for the reaction is Cinnoline-
8-carboxylic acid derivative N-2] Amine [IV] is used in an amount of 1 to 10 equivalents relative to 1 equivalent. Examples of solvents include aromatic hydrocarbons such as benzene, toluene, and xylene, halogenated hydrocarbons such as chloroform, carbon tetrachloride, dichloroethane, chlorobenzene, and dichlorobenzene, diethyl ether, diisopropyl ether, dioxane, tetrahydrofuran, and diethylene glycol dimethyl ether. Ethers such as methanol, ethanol, isopropanol, t-butanol, octatool, cyclohexanol, methyl cellosol, diethylene glycol, alcohols such as glycerin, MAu ethyl, ethyl acetate, butyl acetate, diethyl carbonate esters, nitroethane Examples include nitro compounds such as nitrobenzene, acetonitrile, isobutyronitrile, water, and mixtures thereof.

After the reaction is completed, the reaction solution is subjected to normal treatments such as concentration,
If necessary, the desired cinnoline-8-carboxylic acid amine-filled derivative N-4] can be obtained by purification by operations such as recrystallization.

Cinnoline-8-carboxylic acid amide derivative N-5] [In the formula, R1, R8, Y%A1 and A2 represent the same meanings as above. ] is a cinnoline-8-carboxylic acid halide compound represented by the general formula [v] A"0 [wherein Y, A' and A have the same meanings as above, and Z represents a halogen atom] and the general It can be produced by reacting with an amine represented by the formula (Vll [wherein R2 and R8 have the same meanings as above]).

The reaction is usually carried out without a solvent or in a solvent in the presence of a dehydrohalogenating agent, and the reaction temperature ranges from 0°C to 50°C.
The C1 reaction time ranges from 10 minutes to 8 hours, and the amount of reagents used in the reaction is amine [Vll is 1 to 5] per equivalent of cinnoline-8-carboxylic acid halide compound [V].
equivalent, the dehydrohalogenating agent is 1 to 2 equivalents.

Examples of solvents include aliphatic hydrocarbons such as hexane, heptane, ligroin, and petroleum ether, aromatic hydrocarbons such as benzene, toluene, and xylene, and halogenated hydrocarbons such as chloroform, carbon tetrachloride, dichloroethane, chlorobenzene, and dichlorobenzene. Hydrocarbons, ethers such as diethyl ether, diisopropyl ether, dioxane, tetrahydrofuran, diethylene glycol dimethyl ether, ethyl formate, ethyl acetate, butyl acetate,
Esters such as diethyl carbonate, nitro compounds such as nitroethane and nitrobenzene, nitriles such as acetonitrile and isobutyronitrile, pyridine, triethylamine, N,N-diethylaniline, tributylamine, N-
Tertiary amines such as methylmorpholine, formamide,
Examples include acid amides such as N,N-dimethylformamide and acetamide, sulfur compounds such as dimethyl sulfoxide and sulfolane, water, and mixtures thereof.

Examples of the dehydrohalogenation agent include organic bases such as pyridine, triethylamine, and N,N-diethylaniline.

After the reaction is completed, the reaction solution is subjected to conventional post-treatments such as organic solvent extraction and concentration, and if necessary, purified by chromatography, recrystallization, etc. to obtain the desired cinnoline-8-carboxylic acid amide. Derivative (1-5)
can be obtained.

In addition, cinnoline-8-carboxylic acid halide compound [V
] can be easily produced by subjecting the cinnoline-8-carboxylic acid derivative [1-2] to a conventional acid halide.

Next, Table 1 shows some of the active ingredient compounds of the male sterility agent of the present invention produced according to the above production method.

Table 1 Target plants for which the sterility agent of the present invention can be used include, for example, cereals such as rice, wheat, barley, oats, rye, and corn, legumes such as soybeans, and vegetables such as eggplant, tomatoes, and cabbage. Various cultivated plants can be mentioned, such as flowers such as genus, petunias, and zinnias.

When the cinnoline derivative represented by the general formula [I] according to the present invention is used as a male sterility agent, almost complete male sterility can be caused without causing any undesirable side effects on plants.

Furthermore, as described in the Examples, the male sterility agent of the present invention does not have a harmful effect on the pistil, so first-generation hybrid seeds can be easily obtained by cross-pollination.

When using the cinnoline derivative represented by the general formula (1) as an active ingredient of a male sterility agent, it is usually mixed with a solid carrier, liquid carrier, surfactant, or other formulation auxiliary to form an emulsion, a wettable powder, or Formulate into suspensions, granules, liquids, etc.

These preparations contain the compound of the present invention as an active ingredient in a weight ratio of 1 to 80%, preferably 2 to 70%.

Examples of solid carriers include fine powders or granules such as kaolin clay, attapulgite clay, bentonite, acid clay, pyrophyllite, talc, diatomaceous earth, calcite, walnut shell powder, urea, ammonium sulfate, and synthetic hydrous silicon oxide. Examples of liquid carriers include aromatic hydrocarbons such as xylene and methylnaphthalene, alcohols such as isopropanol, ethylene glycol, and cellosolve, ketones such as acetone, cyclohexanone, and isophorone, and vegetable oils such as soybean oil and cottonseed oil. , dimethyl sulfoxide, N,N-dimethylformamide, acetonitrile, water and the like.

Examples of surfactants used for emulsification, dispersion, wet layer, etc. include alkyl sulfate salts, alkyl sulfonate salts, alkylaryl sulfonate salts, dialkyl sulfosuccinate salts, and polyoxyethylene alkylaryl ether phosphate salts. anionic surfactants such as
Examples include nonionic surfactants such as polyoxyethylene alkyl ether, polyoxyethylene alkylaryl ether, polyoxyethylene polyoxypropylene block copolymer, sorbitan fatty acid ester, and polyoxyethylene sorbitan fatty acid ester.

Examples of formulation aids include lignin sulfonate, alginate, polyvinyl alcohol, gum arabic, CMC (carboxymethylcellulose), and PAP (isopropyl acid phosphate).

The present cinnoline derivative is usually formulated and used for foliage treatment, soil treatment, or field water treatment from just before the start of reproductive growth until flowering.

In the case of rice field water treatment, it is necessary to separate male and female plants so that it is difficult for the chemicals to be absorbed by the male plants that are planted next to each other.

When treating the foliage and soil, it is necessary to prevent the male plants from being exposed to chemicals.

When this cinnoline derivative is used as an active ingredient in a male sterility agent, the amount to be treated will vary depending on weather conditions, formulation form, treatment time, method, soil, target crop, target variety, etc., but it is usually 5 no. ~10,000f, preferably 20f~a, ooop, emulsion, hydrating agent,
For suspensions, liquids, etc., the prescribed amount is usually 1 per are.
It is diluted with 1 to 10 liters of water (adding an auxiliary agent such as a spreading agent if necessary) for treatment, and granules and the like are usually treated as they are without any dilution.

Examples of the spreading agent include, in addition to the above-mentioned surfactants, polyoxyethylene resin acids (esters), lignin sulfonates, abietates, dinaphthylmethane disulfonates, paraffins, and the like.

It can also be used in combination with other plant growth regulators, herbicides, insecticides, acaricides, nematicides, fungicides, fertilizers, soil conditioners, etc. Moreover, the same plant body can be treated with the present cinnoline derivative several times at different treatment times.

′ For example, the following method is suitable for obtaining a large amount of hybrid seeds.

In other words, the two parents to be crossed are planted alternately. At this time, the number of rows, width, etc. of each parent vary depending on the target crop, target variety, environmental conditions, etc. Then, the female plant is treated with the present male sterility agent, and the female plant that has become male sterile is pollinated with the pollen of the male plant mediated by the wind or an insect key, and hybrid seeds are obtained.

<Examples> The present invention will be explained in more detail below using production examples, formulation examples, and test examples, but the present invention is not limited only to these examples.

First, a production example of the present cinnoline derivative will be shown.

Production Example 1 Ethyl 2-((4-)lifluoromethoxyphenyl)
-1,1-diazandiyl]-(2,6-difluorobenzoyl)acetate-)4.24f1 Potassium carbonate 1.4
1f, dibenzo-18-crown-6,10q N, N
- 20 ml of dimethylformamide and the solution was heated at 100° C. for 1 hour. After cooling to room temperature, add 10 ml of ice water
This solution was poured at 0 fd. After standing for 2 hours, the resulting crystals were collected by filtration.

The crystals were washed twice with 20 ml of water and dried under reduced pressure to obtain the desired ethyl 1-(4-)lifluoromethoxyphenyl)-1,4-dihydro-4-oxo-5-fluorocinnoline-8-. 8.93f of carboxylate was obtained (yield 97.8%) m, p* 178.0°C Production Example 2 Ethyl 2-[(4-difluoromethoxyphenyl)-
t,t-diazanediyl]-(2,6-dichlorobenzoyl)acetate+, soy and potassium carbonate 1.50f
was added to 25 sJ of N,N-dimethylformamide and the solution was heated at 100° C. for 1.6 hours. After cooling to room temperature, this solution was poured into 100 d of ice water to precipitate crystals.

The crystals were collected temporarily and washed with 20 ml of water. Recrystallize from ethyl alcohol to obtain the desired ethyl 1-(4-
difluoromethoxyphenyl)-1,4-dihydro-4
-Oxo-5-chlorocinnoline-8-carboxylate 8.68F was obtained (yield 98.4%) m, p
, 184°C Production Example 8 Ethyl 1-(4-trifluoromethoxyphenyl)-
1,4-dihydro-4-oxo-5-fluorocinnoline-8-carboxylate 2.811 and potassium hydroxide 0.6Tf were mixed with 24 ml of ethyl alcohol and 6 w of water.
1 and stirred at 60-70°C for 7 hours.

After cooling to room temperature, it was diluted with 100 d of water and washed with 80 yxl of diethyl ether. When the aqueous layer was neutralized to pH 2 with concentrated hydrochloric acid, crystals were precipitated.

The crystals were collected by filtration and washed twice with 20 rR/water.

When dried under reduced pressure, the desired 1-(4-trifluoromethoxyphenyl)-1,4-dihydro-4-oxo-5-
2.141 fluorocinnoline-8-carboxylic acid was obtained (yield 99.5%) m, p, 2kO ~ 205°C
(Decomposition) Production Example 4 l-(4-trifluoromethoxyphenyl)-1,4-
Dihydro-4-oxo-5-fluorocinnoline-8-
405q of carboxylic acid and 1.21 ml of 0.827M potassium hydroxide aqueous solution were added to 10s/ml of water and stirred at room temperature for 8 hours. The reaction solution was washed with 10 g of ethyl acetate. After concentrating the water and drying the resulting crystals, the desired 1-(4-trifluoromethoxyphenyl)-1,4-dihydro-4-
Potassium oxo-5-fluorosin'noline-8-carboxylate was obtained at 406 capes (yield 100%), P@1
98-218"C (decomposition) Production example 5 l-(4-)lifluoromethoxyphenyl)-1,4-
Dihydro-4-oxo-5-fluorocinnoline-8-
868M of carboxylic acid, 179 da of thionyl chloride and 50 da of pyridine were dissolved in 10 g of toluene, and the solution was heated under reflux for 2 hours. After cooling to room temperature, this solution was mixed with diethylamine 146w9 and triethylamine 15 under water cooling.
The mixture was added dropwise to a solution of 10 g/ethyl acetate.

After stirring at room temperature for 8 hours, it was set aside overnight. After pouring the reaction solution into 80ml of diluted hydrochloric acid containing ice, the product was extracted twice with 20g/20ml of ethyl acetate. The organic layer was washed with saturated aqueous sodium bicarbonate solution, saturated brine moss (1ONt), and then washed with anhydrous magnesium sulfate. After concentrating the solvent, the residue was purified by silica gel chromatography (eluent: n-hexane-acetone) to obtain the desired N,N-diethyl 1-(4-)lifluoromethoxyphenyl)-1,4-dihydro- 4-oxo-5
-fluorocinnoline-8-carboxamide for 14 s
2 obtained (yield 88.8%) m, I), 11
8.5°C Next, some of the compounds of the present invention produced according to these production methods are shown in Table 2.

Table 2 shows examples of formulations. In addition, this cinnoline derivative has a second
Indicated by compound number in the table. Parts represent parts by weight.

Formulation Example 1 50 parts of compound (21), 3 parts of potassium lignosulfonate, 2 parts of sodium lauryl sulfate, and 45 parts of synthetic hydrous silicon oxide are thoroughly ground and mixed to obtain a wettable powder.

Formulation Example 2 10 parts of compound (8), 14 parts of polyoxyethylene styrylphenyl ether, 6 parts of calcium dodecylbenzenesulfonate and 70 parts of xylene are thoroughly mixed to obtain an emulsion.

Formulation Example 8 2 parts of compound (8), 1 part of synthetic hydrous silicon oxide, 2 parts of calcium lignin sulfonate, 80 parts of bentonite and 65 parts of kaolin clay were ground and mixed, and after adding water and kneading well, The granules are dried to obtain granules.

Formulation Example 4 25 parts of compound (40), 8 parts of polyoxyethylene sorbitan monooleate, 8 parts of CMC and 69 parts of water are mixed and wet-milled until the particle size becomes 5 microns or less to obtain a suspension.

Formulation Example 5 8 parts of compound (7), 1 part of polyoxyethylene styrylphenyl ether, and 96 parts of water are mixed to obtain a liquid preparation.

Next, test examples will show that the present cinnoline derivative is useful as an active ingredient of a male sterility agent. The present cinnoline derivatives are indicated by compound numbers in Table 2.

Test Example 1 Sterility confirmation using wheat 11200
ml plastic pot filled with artificial soil,
Wheat (product 1: Norin No. 61) was sown and the temperature was raised to 27°C.
It was grown under greenhouse conditions with a night temperature of 20° C. and a 115-hour day length. Thereafter, the test compound was formulated into an emulsion or aqueous solution in the same pot eight times in total, 0 to 4 days before the onset of heading, 7 to 11 days before, and 14 to 18 days before the onset of heading. The diluted solution was applied to the foliage from above the plant using a small sprayer at a volume of 10 liters per are.

After heading, flowering, and ripening, four ears were harvested per pot, and the number of spikelets and seeds were examined. The test was conducted in one pot per treatment area.

The sterility rate and fertility rate were calculated using the following formulas.

A = Number of seeds per spikelet in untreated plot B = Number of seeds per spikelet in treated plot Sterility rate (%) = (1--)X100 Fertility rate (%) = -X100 The results are shown in Table 8. . The test compounds exhibited sterility at or near 100%.

Table 8 Test Example Confirmation of male sterility and female fertility using wheat A 1/10,000a Wagner pot was filled with artificial soil.
Wheat (Norin No. 61) was grown in the same manner as in Test Example 1. Thereafter, 18 or 6 days before the beginning of heading, the test compound was used for hand pollination with pollen obtained from two ears from the same ears as in Test Example 1 that had not been treated with other chemicals.

After ripening, the free panicles have 4 potted panicles, and the artificially pollinated panicles have 2 panicles.
The panicles were harvested and the number of spikelets and seeds were investigated.゛The test was conducted in one pot per treatment area.

The sterility rate and fertility rate were calculated using the following formulas.

A = Number of seeds per spikelet in untreated area B = Number of seeds per spikelet in treated area Sterility rate (%) = (1-1)X100 Fertility rate (%) = -X100 The results are shown in Table 4 . Compound (8) showed sufficient sterility at both the image processing times, whereas the fertility rate of artificially pollinated panicles was 58.0% and 42.5%, indicating that sufficient seeds were produced and female fertility was observed. It was recognized that there is.

Table 4 Male sterility and female fertility test example 8 for wheat
Test on selectivity between male sterility and chemical damage using wheat Wheat was grown in the same manner as Test Example 1.

Then, 10 days before the beginning of heading, the test compound was added to Test Example 1.
The stems and leaves were treated in the same manner.

After heading, flowering, and ripening, 4 ears were harvested per pot, and the number of spikelets and seeds were investigated.

After calculating the sterility rate in the same manner as in Test Example 1, the sterility rate of 80% or more is A, and the sterility rate of 50 to 79% is B.

Less than 50% was classified as C.

On the other hand, regarding chemical damage, we mainly observe the chemical damage to ears with the naked eye, and A indicates that there is no or almost no chemical damage, and B1 indicates that the chemical damage is within the acceptable range (the chemical damage appears on the heads but does not extend to the pistils). Those outside the acceptable range (those whose chemical damage extended to the pistil) were rated C.

The test was conducted in 8 pots per treatment area. The results are shown in Table 5.

Table 5 Winter ethyl 1-(4-chlorophenyl)-1゜4-dihydro-4-oxocinnoline-3-carboxylate (
Compounds described in JP-A No. 61-249972) Compounds (2) and (8) showed good results in terms of sterility and drug damage in a wide range of dosage, whereas the control compound showed good results. The results showed that a range of dosages that were favorable for both fertility and phytotoxicity was not found, and that if the phytotoxicity was weak, the sterility rate was insufficient, and if the sterility rate was high, the phytotoxicity was also strong.

Test Example 4 Sterility and male fertility test capacity using rice
A 200 wtl plastic pot was filled with artificial soil, and rice was sown and grown under the same conditions as Test Example 1. The plants were submerged in water, and then, 15 or 10 days before the beginning of heading, the test compound was applied to the leaves in the same manner as in Test Example 1. Two pots were used per test plot, and one
One pot was used to confirm sterility, and the other pot was used to confirm female fertility. After earing, a pot that had not been treated with chemicals was placed next to it, and pollen from that pot was used for hand pollination. After ripening, four panicles were harvested from each pot, and the number of flowers and seeds were investigated.

The sterility rate and fertility rate were calculated using the following formula.

A = Number of seeds per number of flowers in the untreated area B = Number of seeds per number of flowers in the treated area Sterility rate of free panicle (%) = (,1--)X100 Fertility rate of artificially pollinated panicle ( %)=-xto.

The results are shown in Table 6. Compound (2) showed sufficient sterility in the free panicle at both times of image processing.

On the other hand, the artificially pollinated panicle produced a large number of seeds and was found to be female fertile.

Table 6 Test Example 5 Confirmation capacity for sterility and female fertility using morning glory Morning glory (Scarlet O'Hara) was sown in a 200 ml plastic pot filled with field soil, and the liquid was placed at a room temperature of 27°C. The plants were grown for 7 days under greenhouse conditions with a temperature of 20'015 hours and a photoperiod of 20'015 hours.

Thereafter, for 14 days, short-day treatment was carried out in an artificial climate room with room temperature and night temperature of 22° C. and 8-hour day length. Thereafter, the conditions were returned to the greenhouse, and the same pot was treated with the test compound in the same manner as Test Example 1 a total of 8 times on 21.28.85 after sowing. Two pots were used per treatment area.

After flowering, 6 flowers per treatment plot were visually observed and evaluated according to the following criteria.

Effect on pollen A: No throttling at all B: Throttling but low pollen amount C: Throttling and pollen amount is normal Chemical damage A: No chemical damage (no or only a slight amount observed) B: Phytotoxicity is observed, but it does not affect the pistil. C: Phytotoxicity is also observed on the pistil.

In addition, artificial pollination was performed on flowers with A effect on leopards and flowers in the untreated area. In addition, the fish in the untreated area were emasculated in advance before opening. As a result, it was confirmed that both the plots treated with compound (80) and the plots not treated were fertile.

Furthermore, as shown in Table 7, compound (80) exhibited male sterility, and produced fertile seeds without causing any phytotoxicity.

Table 7 <Effects of the invention> The present cinnoline derivative has an excellent male sterility effect,
Moreover, it is useful as a male sterility agent because it does not cause any harmful effects on crops.

Claims (1)

[Claims] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, X represents -OH, -O^-M^+, -OR^1, or ▲There are mathematical formulas, chemical formulas, tables, etc.▼ . M represents an alkali metal cation, an alkaline earth metal cation, or ▲There are mathematical formulas, chemical formulas, tables, etc.▼. R^1 represents a lower alkyl group, a lower alkenyl group, a lower alkynyl group, a lower alkoxyalkyl group, a halo-lower alkyl group, a cycloalkyl group, a benzyl group or a phenyl group. R^2 and R^3 are each the same or different, hydrogen atom, lower alkyl group, lower alkenyl group, lower alkynyl group, cycloalkyl group, benzyl optionally substituted with up to two methyl groups at the α-position; base,
Represents a hydroxyalkyl group, or a phenyl group which may be substituted with the same or different lower alkyl group or halogen atom. R^4, R^5 and R^6 are the same or different and each represents a hydrogen atom, a lower alkyl group, a lower alkenyl group, a lower alkynyl group, a cycloalkyl group, a benzyl group or a phenyl group. Y represents a fluorine atom, a chlorine atom, a trihalomethyl group or a lower alkoxy group. A^1 represents a halo-lower alkyl group, and A^2 represents a hydrogen atom or a halogen atom. ] A male sterility agent for plants, characterized by containing a cinnoline derivative represented by the following as an active ingredient.