CN116784347A - Weeding composition, herbicide and application - Google Patents

Abstract

The application discloses a weeding composition, which comprises active ingredients of metasulfuron and quinclorac, wherein the mass ratio of metasulfuron to quinclorac is (0.15-9.57): 1. the combined use of the bupirimate and the quinclorac shows additive or synergistic effect, is very safe to the zoysia japonica lawn in the warm-season lawns, and has good effect on removing gramineous weeds in the warm-season lawns due to the combined action of the bupirimate and the quinclorac, and has less environmental pollution, thus being capable of being popularized and applied on a large scale.

Description

Herbicidal composition, herbicide and application

Technical field

The present invention relates to the technical field of agricultural herbicides, specifically a herbicidal composition, herbicide and application.

Background technique

Lawn grasses can be divided into warm-season grasses and cool-season grasses according to their ecological adaptability to temperature. The most suitable temperature for warm-season grass to grow is 25 to 35 degrees Celsius, and it can survive safely in the range of -5 to 42 degrees Celsius. This type of grass grows vigorously in summer or warm areas. Zoysia grass is a warm-season lawn grass species. More cold-resistant grass species. Warm-season turfgrass is not only in huge demand, but also comes in many varieties. However, it is susceptible to the influence of gramineous weeds (such as Imperata cogongrass) with strong root systems and strong reproductive capabilities, resulting in a decrease in the reproductive capability of warm-season turfgrass and the inability to grow normally. .

In garden lawn maintenance, weed control is a very arduous task. Manual removal is expensive and incomplete, and weeds can easily recur. A more effective method is to use highly selective chemical herbicides to control lawn weeds. According to the China Pesticide Information Network, as of December 2021, there are 24 domestically registered pesticides used to control lawn weeds. The main ingredients involved are: Cisulfuron-methyl, mesotrione, atrifluroline, fluopyron, flusulam, clopyralid, dicamba, oxazofop-alin, sodium 2-methyl-4 chloride, trifluoride Disulfuron et al.

However, the above pesticides are not effective against grassy weeds. Long-term use will cause the lawn weeds to become more and more harmful and have a great impact on the growth of the lawn. Too many grasses will cause lawn degradation, and in severe cases, the death of the lawn. Impact on the garden landscape. Controlling grassy weeds in lawns is a technical problem that troubles garden maintainers. Agents that are safe for lawn grasses have no significant effect on grassy weeds, and agents that are effective against grassy weeds are unsafe for turfgrass.

Contents of the invention

In order to solve the defects existing in the prior art, the present invention provides a herbicidal composition, herbicide and application. It has good control effect on gramineous weeds such as Imperata cogongrass, high lawn safety and less environmental pollution.

In order to achieve the above objects, the present invention adopts the following technical solutions:

In a first aspect, the present invention provides a herbicidal composition, the active ingredients of which include methylsulfuron-methyl and quinclorac, and the mass ratio of methylsulfuron-methyl and quinclorac is (0.15-9.57): 1 .

Preferably, the mass ratio of metsulfuron-methyl and quinclorac is (1.2-2.4):1.

In a second aspect, the present invention provides a herbicide, including the herbicidal composition and an auxiliary agent.

Preferably, the auxiliary agent is sodium p-chlorophenoxyacetate.

Preferably, the ratio of the total mass of the metosulfuron-methyl and quinclorac to the mass of the sodium p-chlorophenoxyacetate is (240-510):1.

More preferably, the ratio of the total mass of metsulfuron-methyl and quinclorac to the mass of sodium p-chlorophenoxyacetate is (330-510):1.

In a third aspect, the present invention provides an application of the herbicidal composition or herbicide in controlling gramineous weeds in warm-season lawns.

Preferably, the warm-season lawn of the present invention is a Zoysia lawn.

Preferably, the gramineous weeds described in the present invention are weeds such as Imperata cognac, crabgrass, green foxtail, tigertail grass, barnyardgrass and other weeds.

Preferably, the application dosage of the active ingredient of the composition or the herbicide is 0.0225-0.09g/m ² of metosulfuron-methyl, 0.0375-0.075g/m ² of quinclorac, and 0.00025g of sodium p-chlorophenoxyacetate. /m ² .

Preferably, the application conditions of the herbicidal composition or herbicide of the present invention are: watering the day before or on a sunny day after rain, under the condition of clear and windless weather, between 9:00-11:00 or 15:00-18:00 time period of administration.

Preferably, the herbicidal composition or herbicide application method of the present invention includes any one of field-wide stem and leaf spraying, directional spraying, directional smearing, aircraft spraying and mechanical spraying.

The beneficial effects of the present invention are:

The active ingredients of the herbicidal composition of the present invention are metosulfuron methyl and quinclorac. The combined use of the two exhibits additive and synergistic effects, and is very safe for zoysia grass lawns in warm-season lawns. As a systemic grass herbicide, chloroquinclorac can enhance the absorption of metosulfuron-methyl by grass weeds. The two work together to make the herbicide have a good effect on the removal of grass weeds in warm-season lawns. , and has less environmental pollution, and can be promoted and applied on a large scale.

In the present invention, sodium p-chlorophenoxyacetate is added to the composition to regulate hormones in the plant, promote the plant to absorb water and medicinal liquid, so that methylsulfuron-methyl and quinclorac can be better absorbed by undergraduate weeds. Absorption.

Detailed ways

In order to enable those skilled in the art to better understand the technical solution of the invention, the invention will be further described in detail below in conjunction with specific embodiments.

The present invention has developed a herbicide formula that is suitable for warm-season lawns, has good control effects on gramineous weeds such as Imperata cogongrass, has high lawn safety, has less environmental pollution, and can be popularized and applied on a large scale.

Specifically, in the first aspect, the present invention provides a herbicidal composition, the active ingredients of which include methylsulfuron-methyl and quinclorac, and the mass ratio of methylsulfuron-methyl and quinclorac is (0.15-9.57) :1. Exemplarily, the mass ratio of metsulfuron-methyl and quinclorac is any one of 0.15:1, 0.3:1, 0.6:1, 1.2:1, 2.4:1, 4.8:1, and 9.57:1 or a value between the two. Preferably, the mass ratio of metsulfuron-methyl and quinclorac is 1.2:1 or 2.4:1.

Mesulfuron-methyl, as a sulfonylurea herbicide, is systemic and inhibits the synthesis of branched-chain amino acids. It can inhibit cell division of plant meristematic tissue and prevent plant growth. The appearance of plants will show obvious red-purple, chlorosis, necrosis, Vein chlorosis and end bud death are usually used in non-arable land. Almost any grass can be killed and no grass will grow. However, the inventor of the present application creatively discovered after extensive research that the combination of metosulfuron and quinclorac It is very safe for zoysia lawns in warm-season lawns. As a systemic grass herbicide, quinclorac can enhance the absorption of metosulfuron-methyl by grass weeds. The synergistic effect of the two makes Herbicides are effective in removing grassy weeds in warm-season lawns.

In a second aspect, the present invention provides a herbicide, including the herbicidal composition and an auxiliary agent.

Preferably, the auxiliary agent is sodium p-chlorophenoxyacetate. It regulates hormones in plants, promotes the plants to absorb water and liquid medicine, so that metsulfuron-methyl and quinclorac can be better absorbed by undergraduate weeds. In some embodiments of the present invention, the ratio of the total mass of metsulfuron-methyl and quinclorac to the mass of sodium p-chlorophenoxyacetate is (240-510): 1. Preferably, the ratio of the total mass of metsulfuron-methyl and quinclorac to the mass of sodium p-chlorophenoxyacetate is (330-510):1.

The herbicide of the present invention also includes pesticide acceptable auxiliary materials.

The herbicides described in the present invention can be in the form of solid preparations (such as granules, etc.) or liquid preparations (such as wettable powders, aqueous emulsions or emulsifiable concentrates, etc.) conventional in the art.

In some embodiments of the present invention, the metosulfuron-methyl is a commercially available dispersible granule, the quinclorac is a commercially available saline agent, and the sodium p-chlorophenoxyacetate is a commercially available soluble solution. Agents, and their commercial sources are all conventional choices in this field. It should be noted that no matter what dosage form the composition is, as long as the active ingredients meet the mass ratio described in the present invention, the technical effects described in the present invention can be achieved.

In a third aspect, the present invention provides an application of the herbicide in controlling gramineous weeds in warm-season lawns.

Preferably, the warm-season lawn of the present invention is a Zoysia lawn.

Preferably, the gramineous weeds described in the present invention are weeds such as Imperata cognac, crabgrass, green foxtail, tigertail grass, barnyardgrass and other weeds.

During the application process of the present invention, the application dosage of the active ingredients of the composition or the herbicide is 0.0225-0.09g/m ² of metosulfuron-methyl, 0.0375-0.075g/m 2 of quinclorac, and 0.0375-0.075g/m ² of p-chlorophenoxy Sodium acetate 0.00025g/m ² .

The application conditions of the herbicidal composition or herbicide of the present invention are: watering the day before or on a sunny day after rain, with clear and windless weather, application in the time period of 9:00-11:00 or 15:00-18:00 . During this period, when the temperature is suitable, watering or sunny days after rain, the plants absorb water and the lenticels open, which is conducive to the absorption of the medicinal solution.

The herbicide of the present invention can also be combined with broad-leaf herbicides such as butoxyethyl chloropyroxyacetate, dimethyltetrachloroisooctyl, dichloropyridine, etc. to control herbicides in Zoysia lawns. All other weeds.

The herbicidal composition or herbicide application method of the present invention includes: any one of field-wide stem and leaf spraying, directional spraying, directional smearing, aircraft spraying and mechanical spraying.

It should be noted that when applying the herbicidal composition or herbicide of the embodiment of the present invention, each active ingredient of the embodiment of the present invention may be applied separately or simultaneously.

The above is a detailed description of the present invention, and the following is an embodiment of the present invention.

Example 1

The preparation method of the herbicide in this embodiment is:

S1. Add 0.3g of 75% metsulfuron-methyl water-dispersible granules into a beaker containing 100ml of water, and stir thoroughly to completely disperse the agent in the water;

S2. Add 2.34g of 32% quinclorac aqueous solution into a beaker containing 100ml of water, and stir thoroughly to completely disperse the agent in the water;

S3. Add 0.25g of 1% sodium p-chlorophenoxyacetate soluble agent into a beaker filled with 100ml of water, and stir thoroughly to completely disperse the agent in the water;

S4. Put the medicine obtained in S1, S2 and S3 into a 1L beaker, mix evenly and add water to 700ml, then take out 70ml to obtain 630ml of mixed solution.

The mass ratio of metsulfuron-methyl: quinclorac: sodium p-chlorophenoxyacetate in the herbicidal composition of this embodiment is: 90:300:1.

Example 2

The preparation method of the herbicide in this embodiment is:

S1. Add 0.3g of 75% metsulfuron-methyl water-dispersible granules into a beaker containing 100ml of water, and stir thoroughly to completely disperse the agent in the water;

S2. Add 1.17g of 32% quinclorac aqueous solution into a beaker containing 100 ml of water, and stir thoroughly to completely disperse the agent in the water;

S3. Add 0.25g of 1% sodium p-chlorophenoxyacetate soluble agent into a beaker filled with 100ml of water, and stir thoroughly to completely disperse the agent in the water;

S4. Put the medicine obtained in S1, S2 and S3 into a 1L beaker, mix evenly and add water to 700ml, then take out 70ml to obtain 630ml of mixed solution.

The mass ratio of metsulfuron-methyl: quinclorac: sodium p-chlorophenoxyacetate in the herbicidal composition of this embodiment is: 90:150:1.

Example 3

The preparation method of the herbicide in this embodiment is:

S1. Add 0.6g of 75% metsulfuron-methyl water-dispersible granules into a beaker containing 100ml of water, and stir thoroughly to completely disperse the agent in the water;

S2. Add 1.17g of 32% quinclorac aqueous solution into a beaker containing 100 ml of water, and stir thoroughly to completely disperse the agent in the water;

S3. Add 0.25g of 1% sodium p-chlorophenoxyacetate soluble agent into a beaker filled with 100ml of water, and stir thoroughly to completely disperse the agent in the water;

S4. Put the medicine obtained in S1, S2 and S3 into a 1L beaker, mix evenly and add water to 700ml, then take out 70ml to obtain 630ml of mixed solution.

The mass ratio of metsulfuron-methyl: quinclorac: sodium p-chlorophenoxyacetate in the herbicidal composition of this embodiment is: 180:150:1.

Example 4

The preparation method of the herbicide in this embodiment is:

S1. Add 1.2g of 75% metsulfuron-methyl water-dispersible granules into a beaker containing 100ml of water, and stir thoroughly to completely disperse the agent in the water;

S2. Add 1.17g of 32% quinclorac aqueous solution into a beaker containing 100 ml of water, and stir thoroughly to completely disperse the agent in the water;

S3. Add 0.25g of 1% sodium p-chlorophenoxyacetate soluble agent into a beaker filled with 100ml of water, and stir thoroughly to completely disperse the agent in the water;

S4. Put the medicine obtained in S1, S2 and S3 into a 1L beaker, mix evenly and add water to 700ml, then take out 70ml to obtain 630ml of mixed solution.

The mass ratio of metsulfuron-methyl: quinclorac: sodium p-chlorophenoxyacetate in the herbicidal composition of this embodiment is: 360:150:1.

Effect example 1

The herbicides of the examples were sprayed on the warm-season Zoysia lawn to study the safety of the turfgrass and the death of Imperata weeds among the grassy weeds, and to explore the synergistic effect of the composition in controlling grassy weeds. , clarify the reasonable ratio of the composition.

1. Lawn pretreatment: The lawn type is warm-season Zoysia lawn, with consistent lawn management level and uniform and medium fertility. The main weeds in the test area are broad-leaf weed Imperata cogongrass, which is evenly distributed. The lawn is removed with a hand-push weeder. Trim to the same height with the blade set to about 3cm.

2. Preparation of chemicals: Spray the herbicides obtained in Examples 1 to 4 and the clean water in the control area, in which 630 mL of clean water is used in the control area, and each treatment is repeated three times.

3. Test method: On September 24, 2021, 15 sample plots were selected in areas where the damage of Zoysia turf and Imperata is more serious, with each plot area 3m × 3m = 9m ² . Water the day before application or on a sunny day after rain, when the weather is clear and windless, use a back sprayer to evenly spray the lawn weeds "Imperata" between 9:00-11:00 or 15:00-18:00. Spray, do not spray too much, do not miss spray, the application amount is shown in the table below.

Table 1 Application dosage of active ingredients in each embodiment

4. Evaluation method:

4.1 Evaluation of joint effects of compositions

The joint action type of the composition is evaluated by the Gowing method, which is a method for evaluating the joint action type of mixed herbicides proposed in 1960. Specific steps: first measure the control effect of a single agent and a mixture on target weeds, calculate the theoretical control effect of the mixture based on the measured control effect of the single agent, and then compare it with the measured control effect of the mixture to evaluate the combined effect type.

The formula for calculating the mixing effect of Gowing method is:

E0＝X+Y–XY/100

X represents the weed control effect of herbicide A when the dosage is P; Y represents the weed control effect of herbicide B when the dosage is Q; E0 represents the weed control effect of herbicide (A+B) when the dosage of herbicide is (P+Q) Theoretical control effect, E in the formula represents the measured control effect % of each treatment. According to the Gowing method, when E-E0>10%, it means that the mixed herbicide has a synergistic effect; when E-E0<-10%, it means that the mixed herbicide has an antagonistic effect; when the E-E0 value is between ± At 10%, it means that the mixed herbicides have an additive effect.

4.2 Lawn safety evaluation

(1)Pharmacological harm level

Investigate the growth of the lawn 3 days, 7 days, and 15 days after the application. The safety of the lawn refers to Wei Fuxiang's herbicide damage test method. Observe the growth status, color, and leaf status of the lawn ground cover plants after the application. The degree of phytotoxicity was scored, and the scoring method is shown in Table 2.

Table 2 Lawn pesticide damage levels

(2) Lawn phytotoxicity index:

After application, observe the phytotoxicity of the lawn, count the phytotoxicity levels and number of plants in each treatment, and calculate the phytotoxicity index according to formula (1). Surveys were conducted 3 days, 7 days, and 15 days after pesticide application, a total of 3 surveys were conducted, and the average value was calculated and recorded as the average phytotoxicity index of turfgrass.

In the formula: I _P is the phytotoxicity index; G _i is the phytotoxicity level; _Li is the number of plants with phytotoxicity level; L _s is the total number of plants investigated; G _m is the highest phytotoxicity level.

(3) Plant height inhibition rate and growth rate inhibition rate:

Randomly select 10 sample points in each plot, measure the natural height of the lawn, and calculate the plant height inhibition rate and growth rate inhibition rate.

In the formula: H _t is the height of the control lawn after t days (cm); H ₀ is the height of the control lawn (cm); ΔH _t is the lawn growth rate in the control area (cm/d); h _t is the height of the lawn in the treatment area after t days (cm ); h ₀ is the lawn height in the treatment area (cm); Δh _t is the lawn growth rate in the treatment area (cm/d); E _h is the plant height inhibition rate (%).

4.3 Control effect of corrected weed strains

Record the number of weed Imperata plants in the sample area before and after spraying the pesticide solution on 3d, 7d, and 15d, and calculate the control effect of Corrected Imperata plants.

E represents the corrected plant control effect (%); CK ₀ represents the number of weed plants (plants) in the blank control area before pesticide application; CKt represents the number of weed plants (plants) in the blank control area after pesticide application; P ₀ represents the pesticide application in the treatment area The number of weeds (plants) before; Pt represents the number of weeds (plants) in the chemical treatment area after application.

5. Test results:

5.1 Evaluation of joint effects of compositions

Table 3 Evaluation results of herbicidal activity and combined effect of different composition ratios on Imperata corymogonata

The results show that: The evaluation results of the joint effect of the compositions show that the measured control effect (E) of most herbicide compositions on the tested weeds is greater than the theoretical control effect (E0). When the ratio of metsulfuron-methyl and quinclorac is When it is 1.2 and 2.4, the EE ₀ value is greater than 10%, and the combined effect type of the mixture is synergistic. When the specific gravity of quinclorac is low or the specific gravity of metsulfuron-methyl is low, the type of mixture effect is additive, and there is no Antagonism occurs.

5.2 Lawn safety evaluation

(1)Pharmacological harm level

After applying the herbicides of Examples 1 to 4 for 3 days, 7 days, and 15 days, the Zoysia turf herb showed no phytotoxicity phenomena such as leaf yellowing, bending, and wilting, and the phytotoxicity levels of the lawn were all level 0, which illustrates the present invention. The herbicide is safe for Zoysia lawns.

(2) Lawn phytotoxicity index

After applying the herbicides of Examples 1 to 4 for 3 days, 7 days, and 15 days, it was calculated according to formula (1) that the phytotoxicity index was all 0, and the lawn phytotoxicity levels were all level 0, indicating that the herbicides of the present invention have a negative impact on the effects of the herbicides on the furrow leaves. Grass lawn safety.

(3) Plant height inhibition rate and growth rate inhibition rate

The plant height and growth rate were tested on the lawns where the herbicides of Examples 1 to 4 were applied after 3 days, 7 days, and 15 days. The results are shown in Tables 4 and 5.

Table 4 The effect of herbicides on plant height inhibition in Zoysia lawns

Note: The above data are average values, n=3.

The results in Table 4 show that after 3 days of application, the plant height of the herbicide-treated lawns of Examples 1 to 4 was significantly lower than that of the control treatment. There was no significant difference in the plant height inhibition rate of each treatment on the Zoysia furrow lawn. The plant height inhibition rate It was 69.44% to 80.55%; 7 days after application, the plant height of the herbicide-treated lawns in Examples 1 to 4 was significantly lower than that of the control treatment. There was no significant difference in the plant height inhibition rate of the Zoysia turf lawns in each treatment. The plant height inhibition Compared with the plant height inhibition rate 3 days after application, the plant height inhibition rate was 24.53% to 28.39%; after 15 days of application, the plant height inhibition rate of each treatment on the Zoysia furrow lawn was reduced, and the plant height inhibition rate was It is 5.87%~7.05%.

Table 5 The inhibitory effect of herbicides on the growth rate of Zoysia lawns

Note: The above data are average values, n=3.

The results in Table 5 show that after 3 days of application, the growth rate of Zoysia turfgrass treated with the herbicides of Examples 1 to 4 was significantly lower than the growth rate of the control lawn; after 7 days of application, the growth rate of Zoysia turfgrass treated with the herbicides of Examples 1 to 4 The growth rate of Zoysia turfgrass treated with herbicides was significantly lower than the growth rate of the control lawn, and the growth rate of Zoysia turfgrass turf in each treatment had no significant effect. Compared with the lawn 3 days after application, the growth rate of Zoysia zoysia treated with the herbicides of Examples 1 to 4 increased by 13 to 18 times after 7 days, and the growth rate in the control area increased by 3 to 4 times. After 15 applications, there was no significant difference in the growth rate of the Zoysia turf treated with the herbicides of Examples 1 to 4 and the control group, and the growth rate was 0.2 cm/d.

Based on the above results, it is shown that no obvious phytotoxicity occurs after the herbicide of the present invention is applied to the Zoysia lawn. After 3 days of application, the growth rate of the lawn was lower than that of the control treatment. After 7 days of application, the growth rate of the lawn was still lower than that of the control treatment. After 15 days of application, the growth rate of the lawn in the application treatment was lower than that of the control treatment. There was no significant difference. The growth rate of the lawn in the control area increased with time, and the growth rate gradually slowed down. Based on the results of comprehensive phytotoxicity level, plant height inhibition rate, and growth rate, it can be seen that the herbicides of the present invention are safe for Zoysia zoysia lawns.

5.3 Evaluation of herbicidal activity

The herbicides in Examples 1 to 4 and the control group were tested for their control effects on Imperata cognac in the Zoysia lawn. The results are shown in Table 6:

Table 6 Herbicide control effects on Imperata cognac in Zoysia lawns

Note: The above data are average values, n=3.

Table 6 shows that: 3 days after spraying the medicinal solution, the upper ends of the Imperata leaves in the Zoysia lawn treated with the medication turned slightly yellow, and a small part of the younger Imperata died. The control effect of Example 1 was about 14.19%. The control effect of the strains of Example 2 was 6.40%, and the control effect of the strains of Examples 3 and 4 reached 20%. The control effect of Examples 3 and 4 on the strains of Imperata cognac was significantly higher than that of Examples 1 and 2. Seven days after spraying the medicinal solution, the upper ends of the Imperata leaves in the Zoysia lawn treated with the medicinal solution were completely withered and yellow, and the internodes turned black and brown. The control effect of Example 1 strain was about 48.54%, and the control effect of Example 2 strain was only 38.62%. %, the strain control effect of Example 3 and Example 4 on Imperata cogongrass reaches more than 60%, and the strain control effect of Example 3 and Example 4 on Imperata cogongrass is significantly higher than that of Examples 1 and 2. Fifteen days after spraying the chemical solution, the aboveground part of Imperata cognac in the Zoysia grass lawn was completely withered, the internodes turned black and brown, and the root system became black and necrotic. The plant control effect of Example 3 and Example 4 on Imperata cogongrass reached 95% % or more, the strain control effects of Examples 3 and 4 on Imperata corysii are significantly higher than those of Examples 1 and 2, and there is no significant difference between Examples 1 and 2.

Comprehensive lawn safety and Imperata weed control effect, the herbicides in Examples 1 to 4 are all safe for Zoysia furrow lawns, and the herbicides in Examples 1 to 4 are all effective against Imperata, among which Example 1 and Example 2 The plant control effect is about 78%, and the plant control effect of Examples 3 and 4 on Imperata cogongrass reaches more than 95%. Combining the control effect and the cost of the agent, the herbicide of Example 3 is preferred.

Effect example 2 Cool-season bluegrass lawn control of Imperata cogongrass

The herbicides in the examples were sprayed on cool-season bluegrass lawns to explore the applicability of the herbicidal composition of the present invention to cool-season lawns.

1. Lawn pretreatment: The lawn type is cool-season bluegrass lawn, with consistent lawn management level and uniform and medium fertility. The main weeds in the test area are broad-leaf weeds Imperata and evenly distributed. The lawn is trimmed with a hand-push weeder to At the same height, the blade is set to about 3cm.

2. Pharmacy configuration: Same effect as Example 1.

3. Test method: The lawn type is cool-season bluegrass lawn, and the other settings are the same as in Effect Example 1.

4. Evaluation method: Same as effect example 1.

5. Test results:

5.1 Lawn safety evaluation

Apply the herbicides obtained in Examples 1 to 4 to bluegrass lawns, observe the phytotoxicity of the lawns 3 days, 7 days, and 15 days after application, and calculate the average phytotoxicity index of the turfgrass, as shown in Table 7.

Table 7 Herbicide damage index to bluegrass turf

Note: The above data are average values, n=3.

The results in Table 5 show that after 3 days, 7 days, and 15 days of application, phytotoxicity occurred in the bluegrass lawn. After 3 days of application, the phytotoxicity level of the lawn was 1. The phytotoxicity of Example 1, Example 2, Example 3, and Example 4 The indexes were 68.00, 69.33, 70.00, and 72.66 respectively; after 7 days of application, the phytotoxicity levels of the lawn were 2 and 3, and the phytotoxicity indexes of Example 1, Example 2, Example 3, and Example 4 were 67.55, 79.33, and 68.67 respectively. , 70.22; after 15 days of application, the phytotoxicity levels of the lawn were 3 and 4. The phytotoxicity indexes of Example 1, Example 2, Example 3 and Example 4 were 76.16, 81.00, 80.33, and 83.17 respectively. The herbicides were all harmful to early maturity. The grass lawn is unsafe. After 15 days, the growth of the bluegrass lawn almost stops and all the leaves wither. This shows that the herbicide of the present invention is only suitable for weeding in warm season lawns and is not suitable for weeding in cold season lawns.

The above are only preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as limiting the present invention, and the protection scope of the present invention should be subject to the scope defined by the claims. For those of ordinary skill in the art, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims (10)

1. A herbicidal composition, characterized in that the active ingredients of the composition include methylsulfuron-methyl and quinclorac, and the mass ratio of the methylsulfuron-methyl and quinclorac is (0.15~9.57) :1. 2. The herbicidal composition according to claim 1, characterized in that the mass ratio of the metsulfuron-methyl and quinclorac is (1.2-2.4):1. 3. A herbicide, characterized by comprising the herbicidal composition and an auxiliary agent. 4. The herbicide according to claim 3, characterized in that the auxiliary agent is sodium p-chlorophenoxyacetate. 5. The herbicide according to claim 4, characterized in that the ratio of the total mass of the metosulfuron-methyl and quinclorac to the mass of the sodium p-chlorophenoxyacetate is (240-510): 1. 6. Application of the herbicidal composition according to claim 1 or 2 or the herbicide according to any one of claims 3 to 5 for controlling gramineous weeds in warm-season lawns. 7. The application according to claim 6, characterized in that the warm season lawn is a zoysia lawn. 8. The application according to claim 6, characterized in that the gramineous weeds are weeds such as Imperata cognac, crabgrass, setaria, tigertail grass, barnyardgrass and other weeds. 9. The application according to claim 6, characterized in that the application amount of the active ingredient of the composition or the herbicide is 0.0225-0.09g/m ² of metosulfuron-methyl and 0.0375-0.075g of quinclorac. /m ² , sodium p-chlorophenoxyacetate 0.00025g/m ² . 10. The application according to claim 6, characterized in that the application conditions of the herbicidal composition or herbicide are: watering the day before or sunny day after rain, under the condition of clear and windless weather, between 9:00-11 :00 or 15:00-18:00 time period.