CN108782563B

CN108782563B - Herbicidal composition containing triclopyr and pyribenzoxim and application thereof

Info

Publication number: CN108782563B
Application number: CN201810971693.7A
Authority: CN
Inventors: 陈国奇; 霍中洋; 张洪程; 高辉; 魏海燕; 郭保卫; 胡雅杰; 韦还和
Original assignee: Yangzhou University
Current assignee: Yangzhou University
Priority date: 2018-08-23
Filing date: 2018-08-23
Publication date: 2021-06-25
Anticipated expiration: 2038-08-23
Also published as: CN108782563A

Abstract

The invention discloses a weeding composition, which is prepared from triclopyr and pyribenzoxim according to the weight ratio of (2.5-40): 1 in proportion. The invention also discloses application of the weeding composition in preventing and controlling weeds in paddy fields. The two agents can respectively kill different groups of weeds with high efficiency, and have obvious synergistic effect after being compounded, thereby improving the drug effect exertion speed of the herbicide, reducing the dosage of the herbicide and further improving the safety of the rice. The herbicide control spectra of the two medicament components are complementary, and after the two medicament components are mixed, the herbicide control spectra can effectively cover gramineous, latifoliate and cyperaceae weeds, including common malignant weeds in rice fields such as barnyard grass, moleplant seed, water bamboo leaf, alternanthera philoxeroides, edible tulip, Chinese iris, heterotype cyperus and the like; and has high activity to perennial malignant weeds and resistant weeds which are extremely difficult to treat in paddy fields, and has huge market potential.

Description

Herbicidal composition containing triclopyr and pyribenzoxim and application thereof

Technical Field

The invention belongs to the technical field of agriculture, and particularly relates to a weeding composition and application thereof.

Background

China is the world with the largest rice yield, the planting area of rice all the year around is 3017.8 hectares (4.5 hundred million mu), the annual rice yield is 2.1 hundred million tons, and the planting area and the yield respectively account for 18.1 percent and 33.6 percent of the total seeding area and the total yield of crops in China. Therefore, ensuring the stable yield of the rice and the safe quality of the rice is one of the basic tasks of the planting industry in China. The weed hazard is one of the main biological disasters faced in rice cultivation, and even if various prevention and control measures are adopted, the rice yield loss directly caused by the weed hazard in the rice field is as high as 13.8-21.4%. At present, weeding by using the herbicide is still the most important means for preventing and controlling the weeds in the paddy fields in China, and the annual sale amount of the herbicide 2014 in the paddy fields in China exceeds 25 billion yuan RMB.

China urgently needs to continuously innovate the varieties of the herbicide in the paddy field. On the one hand, the resistance of the weeds in paddy fields in China to various herbicides is continuously increased and the weeds are damaged by outbreak, and new herbicide varieties are needed to be put into use. At present, various weeds such as Echinochloa weeds (Echinochloa spp.), Euphorbia lathyris (Leptochloa chinensis), Digitaria sanguinalis (Digitaria sanguinalis), monochamus koraiensis (Monochoria korsakowiii), edible tulip (Sagittaria trifolia), Cyperus difformis (Cyperus difformis), Amaranthus aurita (Ammannia arenaria), and the like generate resistance to various herbicides, and the herbicides with serious resistance mainly comprise quinoline carboxylic acid type herbicides such as quinclorac, sulfonylurea type herbicides such as bensulfuron-methyl and pyrazosulfuron-ethyl, pyrimidine sulfonamide herbicides such as penoxsulam, cyhalofop-butyl esters of aryloxyphenoxypropionic acid esters, and the like. The herbicide related to the resistant weeds is mainly a stem leaf treating agent, so that the rice fields treated by the stem leaves after the seedlings of the weeds can be cultivated with the herbicide. More practical herbicide varieties are urgently needed to be put into rice production, the problem of the rice field weed damage is efficiently and safely solved, and meanwhile, the outbreak resistance of weeds to the existing pesticide is delayed. On the other hand, the reduction of the use of chemical pesticides has become the national will of China, and efficient, safe and low-risk herbicide varieties are continuously researched and developed, so that the herbicide varieties with large alternative dosage, high residue and high safety risk not only meet the national requirements, but also are the market development trend.

Triclopyr is a class of systemic, conductive, low toxicity herbicide in picoxycarboxylic acids, also known as Geranium, triclopyr. Absorbed by leaf surface and root system of plant, and conducted to whole plant in plant body, resulting in malformation of root, stem and leaf, depletion of stored substance, embolism or rupture of vascular bundle, and gradual death of plant. The weeding composition is suitable for weeding, killing irrigation, maintaining fire lines, supporting and cultivating pine trees and forest stand transformation before forest forestation, and is used for preventing and killing broad leaf weeds and woody plants in non-cultivated land. The gramineous plants have low sensitivity to triclopyr and have drug resistance. Triclopyr can be decomposed by soil microorganisms in soil with a half-life of 30-46 days. Triclopyr is not registered and used in paddy fields in China at present, but research reports show that triclopyr can be used as a herbicide for treating postemergence stems and leaves of weeds in paddy fields.

The novel triclopyr compound formula is searched for having outstanding practical requirements and application potential for controlling stubborn weeds and herbicide-resistant weeds in paddy fields. It is noteworthy that triclopyr is one of the least resistant herbicides of weeds in the world. The effect of triclopyr in combination with penoxsulam, imazethapyr, fluroxypyr, cyhalofop-butyl, fenoxaprop-p-ethyl, propanil and molinate in paddy fields is reported. The discovery that the mixed use of triclopyr and aryloxyphenoxypropionic acid ester herbicides such as cyhalofop-butyl, fenoxaprop-p-ethyl and the like can cause antagonistic effect and show that the control effect of the agents on gramineous weeds is reduced; and the triclopyr and glufosinate can also generate antagonistic effect when being mixed; the barnyard grass weeds in the rice fields have serious resistance to penoxsulam, and the compound application range of the triclopyr and the penoxsulam is limited; the safety of the fluroxypyr, the propanil and the gramineae is poor in production, and the application potential of the triclopyr and the agents in compounding use is limited at present; in addition, imazethapyr can only be used in imidazolinone herbicide-resistant rice fields, and the imidazolinone herbicide-resistant rice varieties which are legally allowed to be used in large areas are not available in China. Therefore, the existing reported triclopyr compound formula is not enough to solve the problem of prevention and control of the weeds in the rice field, and a new compound scheme needs to be created.

The pyribenzoxim is a pyrimidine salicylic acid herbicide, is mainly used for preventing and killing gramineous weeds, broad-leaved weeds and cyperaceae weeds by treating postemergence stems and leaves of paddy fields, and has an obvious effect of preventing barnyard grass. The pyribenzoxim is used for treating stems and leaves after seedlings in paddy fields, and reports show that the pyribenzoxim mixed with methoxone, pyrazosulfuron-ethyl, halosulfuron-methyl, bentazone and propanil can cause antagonistic effect. In addition, paddy field weeds have so far been very weak against pyribenzoxim, and a weed population having a low level of resistance against pyribenzoxim has been found only in a few fields in individual areas.

Disclosure of Invention

The invention aims to solve the technical problem of providing a weeding composition capable of efficiently and safely preventing and removing weeds in paddy fields.

The technical problem to be solved by the present invention is to provide the use of the above herbicidal composition.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows:

a weeding composition comprises triclopyr and pyribenzoxim in a weight ratio of 2.5-40: 1.

Preferably, the weight ratio of the triclopyr to the pyribenzoxim is (5-20) to 1.

Most preferably, the weight ratio of the triclopyr to the pyribenzoxim is (5-10) to 1.

The application of the weeding composition in preventing and killing weeds in paddy fields is also within the protection scope of the invention.

Wherein the weeds are gramineous weeds, broadleaf weeds or cyperaceae weeds, and include but are not limited to barnyard grass, semen euphorbiae, lophatherum gracile, alternanthera philoxeroides, edible tulip, Chinese iris, cyperus rotundus and other common malignant weeds in rice fields.

Particularly, the weeding composition has remarkable weeding effect on perennial malignant weeds, including but not limited to lophatherum gracile, alternanthera philoxeroides, edible tulip and firefly iris.

In addition, the weeding composition provided by the invention is remarkable in treatment of resistant weeds.

When in use, the weeding composition is sprayed on stems and leaves of the rice field at the 3-6 leaf stage of weeds in the rice field and before the 3-leaf stage to the jointing stage of rice, and the effect is obvious.

Has the advantages that: compared with the prior common herbicide for paddy fields, the binary compound herbicide has the following advantages:

(1) the two agents can kill different groups of weeds with high efficiency respectively, and have obvious synergistic effect after being compounded, thereby greatly reducing the dosage of the herbicide and improving the safety of rice.

(2) The herbicide controlling spectra of the two pesticide components are complementary, and after the herbicide controlling spectra are mixed, the weeds of gramineae, broadleaf and cyperaceae can be effectively covered by the herbicide controlling spectra, wherein the weeds comprise common malignant weeds in rice fields such as barnyard grass, moleplant seed, lophatherum gracile, alternanthera philoxeroides, edible tulip, iris lactea, abnormal sedge and the like.

(3) Can kill intractable perennial malignant weeds, and has high activity on the perennial malignant weeds which are extremely difficult to treat in the paddy field, such as lophatherum gracile, alternanthera philoxeroides, edible tulip, Chinese iris, and the like.

(4) The herbicide has quick effect, a large amount of weeds die 7 days after the herbicide is applied, and the weeds die 14 days after the herbicide is applied, so that the competitive advantage of rice seedlings on the weeds can be quickly established when the herbicide is applied to the paddy field, and a foundation is laid for high yield of the rice.

(5) The herbicide composition can be used for controlling resistant weeds, the weeds in the paddy field do not generate resistance to triclopyr at present, the resistance level to pyribenzoxim is low and is only discovered accidentally in a few fields, and the two agents are compounded to effectively control various herbicide-resistant weeds in the paddy field.

(6) The triclopyr-pyribenzoxim is safe for rice and suitable for rice fields with various cultivation modes, and has outstanding safety from the 3-leaf stage to the pre-jointing stage of rice, so that the triclopyr-pyribenzoxim can be used for various rice fields such as mechanical rice transplanting, direct seeding, seedling throwing, manual transplanting and the like.

(7) The two herbicide components have more raw pesticide production enterprises, sufficient raw pesticide supply and lower medicament cost.

Detailed Description

The invention will be better understood from the following examples. However, those skilled in the art will readily appreciate that the description of the embodiments is only for illustrating the present invention and should not be taken as limiting the invention as detailed in the claims.

Example 1: the formula proportion of the triclopyr-pyribenzoxim compound agent is screened and tested.

In order to screen the optimal formula ratio of triclopyr to pyribenzoxim, a series of whole plant bioassays were conducted in the phytotron of the research institute of rice industry and technology at Yangzhou university.

1.1 weeds tested: echinochloa crusgalli (Echinochloa crusgalli), Euphorbia lathyris (Leptochloa chinensis), Sasa albo-marginata (Murdannia triquetra), Alternanthera philoxeroides (Alternanthera philoxeroides), Sagittaria indica (Sagittaria trifolia), Cyperus officinalis (Cyperus difformis), and Iris florea (Scirpus juncoides). When herbicides are used in paddy fields for weeding, weeds are generally classified into three main groups: grassy weeds, broadleaf weeds, cyperaceae weeds and in addition some perennial weeds are seriously harmed. The 7 grasses tested in the test are all the malignant weeds seriously harmful to the existing paddy field and represent different target weed groups, wherein the barnyard grass and the moleplant seed represent the gramineous malignant weeds in the paddy field; herba Lophatheri, Alternanthera philoxeroides and Pseudobulbus cremastrae seu pleiones represent broad-leaf malignant weeds in the rice field; the abnormal-shaped sedges and the Chinese iris represent the malignant weeds in the sedge family of the paddy field. Meanwhile, lophatherum gracile, alternanthera philoxeroides, edible tulip and Chinese iris are typical perennial malignant weeds in the rice field; and barnyard grass, moleplant seed and cyperus rotundus L are typical annual malignant weeds in the paddy field.

1.2 binary compound agent formula ratio screening test medicament dose setting:

1) each single dose setting is as follows:

triclopyr (a): 0(A0), 25(A25), 50(A50), 100(A100) g a.i./hm²；

Pyribenzoxim (B): 0(B0), 2.5(B2.5), 5(B5), 10(B10) g a.i./hm²。

2) The formulation ratio screening dose setting of the binary compound agent is shown in table 1:

TABLE 1 binary compounding agent formula ratio screening dose setting table

A0B0	A25B0	A50B0	A100B0
				A0B2.5	A25B2.5	A50B2.5	A100B2.5
A0B5	A25B5	A50B5	A100B5
				A0B10	A25B10	A50B10	A100B10

1.3 test methods

A square plastic plant cultivation flowerpot with the specification of 7 multiplied by 7cm is filled with organic soil (pH value is 6.5, organic matter content is 2.4%) without herbicide, and water is added until saturation. Selecting barnyard grass with full seeds, semen Euphorbiae Lathyridis, folium Phyllostachydis Henonis, Pseudobulbus Cremastrae seu pleiones, herba Cyperiae Abnormalis and Chinese Iris seed, and sowing 20 seeds in each small flowerpot. The small flowerpot for sowing barnyard grass and edible tulip covers a layer of fine soil (the thickness is about 3mm) on the seeds, and the small flowerpot for sowing Chinese sprangletop, water bamboo leaf, Chinese iris and abnormal sedge is not covered with soil. The alligator alternanthera seedlings are obtained by asexual propagation, 5 sections of alligator alternanthera rhizomes with buds are filled in each small flowerpot, each root-shaped stem is 4cm long, and a layer of fine soil (the thickness is about 5mm) is covered. Placing the small flowerpot into a thickened plastic transfer box (with the depth of 2cm added in advance) with the thickness of 44X 33X 10cm, placing the box in an artificial climate chamber for culturing, illuminating for 14 hours at the temperature of 28 ℃ and dark for 10 hours at the temperature of 25 ℃, and keeping a water layer with the thickness of 1-2cm in the transfer box during the test period so as to ensure that the soil in the small white box is kept moist by absorbing water. After 15 days, the seedlings of each small flowerpot are set, 12 seedlings with the best growth vigor are reserved in each small flowerpot of the barnyard grass, the moleplant seed, the edible tulip, the Chinese iris and the cyperus heterophyllus, and 6 seedlings with the best growth vigor are reserved in each small flowerpot of the lophatherum gracile. After the alligator alternanthera is cultured in the flowerpot for 15 days, 3 seedlings with the best growth vigor are reserved in each small flowerpot. Each treatment was repeated with 4 small pots.

Carrying out herbicide treatment by adopting a stem and leaf spraying method when barnyard grass, moleplant seed, abnormal sedge and Iris lactea seedlings grow to 4-5 leaf stage; the lophatherum gracile, the edible tulip and the alternanthera philoxeroides are treated with herbicide by adopting a stem and leaf spraying method when growing to 6 leaves, and the same amount of clear water is sprayed on a control group. The spraying is carried out by adopting a walking potential pressure-stabilizing spraying tower of the garden and plant protection college of Yangzhou university, the spraying height is 20cm, the spraying amplitude of a flat fan-shaped nozzle is 50cm, and the pressure is 200 KPa. The amount of the sprayed pesticide liquid corresponds to the amount of field sprayed liquid of 45L water/hm². After 21 days of application, the fresh weight of the overground part of the tested weed in each small flowerpot is collected and weighed respectively.

Calculating the fresh weight inhibition rate (E) and the theoretical fresh weight inhibition rate (E) of the weeds among different treatments of the single agent and the binary compound₀). Comparison of E and E by the Gowing method₀The combined action type of the binary compound herbicide is evaluated.

The actual fresh weight inhibition ratio (E) ═ fresh weight of control group-fresh weight of treated group ÷ fresh weight of control group × 100%

Theoretical fresh weight inhibition (E)₀)＝(X+Y-XY)×100％

In the formula E₀The inhibition rate is the theoretical fresh weight inhibition rate of the herbicide triclopyr compounded with pyribenzoxim, X is the actual measurement fresh weight inhibition rate of triclopyr single agent, and Y is the actual measurement fresh weight inhibition rate of pyribenzoxim single agent.

When E-E₀When the concentration is more than 10 percent, the two herbicides have synergistic effect after being compounded; when E-E₀When the content is less than-10 percent, the two herbicides have antagonistic action after being compounded; E-E₀A value of-10% to 10% is an additive effect.

1.4 test results

1) Combined action of triclopyr and pyribenzoxim on barnyard grass

Table 2 actual measurement fresh weight inhibition ratio E (%) -of triclopyr-pyribenzoxim complex agent with different mixture ratios to barnyard grass

TABLE 3 theoretical fresh weight inhibition rate E of triclopyr-pyribenzoxim compound agent with different mixture ratios on barnyard grass₀(％)

"/": theoretical fresh weight inhibition ratio (E) under single-agent treatment₀) Equal to the observed fresh weight inhibition (E) without combined effect.

TABLE 4 Combined action values of triclopyr and pyribenzoxim on barnyard grass [ (E-E) at different ratios₀)×100]

Note: "/" indicates a synergistic effect when E-E0 > 10%: theoretical fresh weight inhibition ratio (E) under single-agent treatment₀) Equal to the observed fresh weight inhibition (E) without combined effect.

As can be seen from Table 2, the triclopyr single agent has almost no inhibitory effect on barnyard grass; 10g of pyribenzoxim mono-dose a.i./hm²The fresh weight inhibition rate exceeds 50%, and the theoretical inhibition rate of the two herbicides in combination is calculated and shown in table 3. The actual measurement inhibition rate and the theoretical inhibition rate of the two herbicides under different compound combinations are compared, the combined action of the two herbicides on barnyard grass is observed in a table 4, and the result shows that the triclopyr and pyribenzoxim have obvious combined action, wherein the triclopyr accounts for 25-100g of a.i./hm²And 2.5-10g of a.i./hm pyribenzoxim²The different dosage combinations show that the actual measured inhibition rate exceeds the theoretical inhibition rate by more than 10 percent, namely the synergistic effect is shown.

2) Combined effect of triclopyr and pyribenzoxim on semen Euphorbiae

TABLE 5 actual fresh weight inhibition E (%)

TABLE 6 theoretical fresh weight inhibition rate E of triclopyr-pyribenzoxim combined agent with different proportions on semen Euphorbiae₀(％)

TABLE 7 Combined action values of triclopyr and pyribenzoxim on Euphorbia lathyris [ (E-E) at different ratios₀)×100]

As can be seen from Table 5, the triclopyr single agent has almost no inhibitory effect on Euphorbia lathyris; 10g of pyribenzoxim mono-dose a.i./hm²The fresh weight inhibition rate is only 26%, and the theoretical inhibition rate of the two herbicides in combination is calculated and shown in table 6. The actual measurement inhibition rate and the theoretical inhibition rate of the two herbicides under different compound combinations are compared, the combined action of the two herbicides on the moleplant seed is observed in a table 7, and the result shows that the triclopyr and the pyribenzoxim have obvious combined action, wherein the triclopyr accounts for 25-100g of a.i./hm²And 2.5-10g of a.i./hm pyribenzoxim²The different dosage combinations show that the actual measured inhibition rate exceeds the theoretical inhibition rate by more than 10 percent, namely the synergistic effect is shown.

3) Combined effect of triclopyr and pyribenzoxim on lophatherum gracile

TABLE 8 actual fresh weight inhibition ratio E (%)

TABLE 9 theoretical fresh weight inhibition rate E of triclopyr-pyribenzoxim combined agent with different proportions on lophatherum gracile₀(％)

TABLE 10 Combined action values of triclopyr and pyribenzoxim on Lophatherum gracile [ (E-E) in different proportions₀)×100]

As shown in Table 8, triclopyr is used as a single dose of 100g a.i./hm²The hour inhibition rate is 18%; 10g of pyribenzoxim mono-dose a.i./hm²The fresh weight inhibition rate is 28%, and the theoretical inhibition rate of the two herbicides in combination is calculated and shown in table 9. The actual measurement inhibition rate and the theoretical inhibition rate of the two herbicides under different compound combinations are compared, the combined action of the two herbicides on the lophatherum gracile is observed in a table 10, and the result shows that the triclopyr and the pyribenzoxim have obvious combined action, wherein the triclopyr accounts for 25-100g a.i./hm²And 2.5-10g of a.i./hm pyribenzoxim²The different dosage combinations show that the actual measured inhibition rate exceeds the theoretical inhibition rate by more than 10 percent, namely the synergistic effect is shown.

4) Combined action of triclopyr and pyribenzoxim on alternanthera philoxeroides

TABLE 11 actual fresh weight inhibition E (%) -of triclopyr-pyribenzoxim combined agent with different mixture ratios on alternanthera philoxeroides

TABLE 12 theoretical fresh weight inhibition ratio E of triclopyr-pyribenzoxim combined agent with different proportions to alternanthera philoxeroides₀(％)

TABLE 13 Combined action value [ (E-E) of triclopyr and pyribenzoxim on alternanthera philoxeroides at different ratios₀)×100]

As shown in Table 11, triclopyr is used in a single dose of 100g a.i./hm²The fresh weight inhibition rate of the alternanthera philoxeroides under treatment is close to 50 percent; 10g of pyribenzoxim mono-dose a.i./hm²The fresh weight inhibition rate under the treatment is less than 15 percent, and the theoretical inhibition rate of the two herbicides in combination is calculated and shown in a table 12. The actual measurement inhibition rate and the theoretical inhibition rate of the two herbicides under different compound combinations are compared, the combined action of the two herbicides on the alternanthera philoxeroides is further investigated and shown in table 13, and the result shows that the triclopyr and the pyribenzoxim have obvious combined action, wherein the triclopyr accounts for 25-100g a.i./hm²And 2.5-10g of a.i./hm pyribenzoxim²The combination of different dosages shows the measured inhibitionThe preparation rate exceeds the theoretical inhibition rate by more than 10 percent, and the synergistic effect is shown.

5) Combined effect of triclopyr and pyribenzoxim on edible tulip

TABLE 14 measured fresh weight inhibition E (%) -of triclopyr-pyribenzoxim combination at different ratios to Pseudobulbus Cremastrae seu pleiones

TABLE 15 theoretical fresh weight inhibition ratio E of triclopyr-pyribenzoxim combined agent to edible tulip in different proportions₀(％)

TABLE 16 Combined action values of triclopyr and pyribenzoxim at different ratios on edible tulip [ (E-E)₀)×100]

As shown in Table 14, triclopyr is used in a single dose of 100g a.i./hm²The fresh weight inhibition rate of the edible tulip under the treatment is 44 percent; 10g of pyribenzoxim mono-dose a.i./hm²The fresh weight inhibition rate under the treatment is only 8%, so that the theoretical inhibition rate of the two herbicides in combination is calculated and shown in table 15. By comparing two herbicidesThe actual measurement inhibition rate and the theoretical inhibition rate under the same compound combination are further investigated, the combined action of the two herbicides on the edible tulip is shown in the table 16, and the result shows that the triclopyr and the pyribenzoxim have obvious combined action, wherein the triclopyr accounts for 25-100g a.i./hm²And 2.5-10g of a.i./hm pyribenzoxim²The different dosage combinations show that the actual measured inhibition rate exceeds the theoretical inhibition rate by more than 10 percent, namely the synergistic effect is shown.

6) Combined effect of triclopyr and pyribenzoxim on heterotype sedges

TABLE 17 actual fresh weight inhibition E (%) -of triclopyr-pyribenzoxim combination at different ratios to sedge heterotypic

TABLE 18 theoretical fresh weight inhibition ratio E of triclopyr-pyribenzoxim combined agent with different proportions to sedge heterotypic₀(％)

TABLE 19 Combined action values of triclopyr and pyribenzoxim at different ratios on cyperus heterophylla [ (E-E)₀)×100]

Note: "/" indicates a synergistic effect when E-E0 > 10%: theoretical fresh weight inhibition ratio (E) under single-agent treatment₀) Equal to the observed fresh weight inhibition rate (E),there is no combined effect.

As shown in Table 17, triclopyr is used in a single dose of 100g a.i./hm²The inhibition rate is 42%; 10g of pyribenzoxim mono-dose a.i./hm²The fresh weight inhibition rate is 18%, and the theoretical inhibition rate of the two herbicides in combination is calculated and shown in table 18. The actual measurement inhibition rate and the theoretical inhibition rate of the two herbicides under different compound combinations are compared, the combined action of the two herbicides on barnyard grass is observed in a table 19, and the result shows that the triclopyr and pyribenzoxim have obvious combined action, wherein the triclopyr accounts for 25-100g of a.i./hm²And 2.5-10g of a.i./hm pyribenzoxim²The different dosage combinations show that the actual measured inhibition rate exceeds the theoretical inhibition rate by more than 10 percent, namely the synergistic effect is shown.

7) Combined effect of triclopyr and pyribenzoxim on firefly iris

TABLE 20 measured fresh weight inhibition ratio of triclopyr-pyrimidineoxime ether combination on Fluiria palla (E%) in different proportions

TABLE 21 theoretical fresh weight inhibition rate E of triclopyr-pyrimidineoxime ether compounded agent with different proportions on Fluiria rubra₀(％)

TABLE 22 Combined action values of triclopyr and pyribenzoxim at different ratios on Fluoritan [ (E-E)₀)×100]

Note: when E-E0 is more than 10 percent, the effect is enhancedAction "/": theoretical fresh weight inhibition ratio (E) under single-agent treatment₀) Equal to the observed fresh weight inhibition (E) without combined effect.

As shown in Table 20, triclopyr is used in a single dose of 100g a.i./hm²The inhibition rate of the fluoria under the treatment is 38 percent; 10g of pyribenzoxim mono-dose a.i./hm²The fresh weight inhibition rate is 26%, and the theoretical inhibition rate of the two herbicides in combination is calculated and shown in a table 21. The actual measurement inhibition rate and the theoretical inhibition rate of the two herbicides under different compound combinations are compared, the combined action of the two herbicides on barnyard grass is observed in a table 22, and the result shows that the triclopyr and pyribenzoxim have obvious combined action, wherein the triclopyr accounts for 25-100g of a.i./hm²And 2.5-10g of a.i./hm pyribenzoxim²The different dosage combinations show that the actual measured inhibition rate exceeds the theoretical inhibition rate by more than 10 percent, namely the synergistic effect is shown.

1.5 conclusion of the test

The 7 weeds selected in the research are common malignant weeds in the paddy field, wherein barnyard grass and moleplant seed represent the malignant weeds in the paddy field; herba Lophatheri, Alternanthera philoxeroides and Pseudobulbus cremastrae seu pleiones represent broad-leaf malignant weeds in the rice field; the abnormal-shaped sedges and the Chinese iris represent the malignant weeds in the sedge family of the paddy field. Meanwhile, lophatherum gracile, alternanthera philoxeroides, edible tulip and Chinese iris are typical perennial malignant weeds in the rice field; and barnyard grass, moleplant seed and cyperus rotundus L are typical annual malignant weeds in the paddy field. Thus, the weeds tested are very representative. The comprehensive research results show that the triclopyr and pyribenzoxim have outstanding inhibition effect and combined synergistic effect on various weeds when being compounded.

The proportion of the triclopyr and pyribenzoxim compound formula is further analyzed, and the triclopyr accounts for 25-100g a.i./hm²And 2.5-10g of a.i./hm pyribenzoxim²The combination and compounding of the components show obvious synergistic effect (E-E)₀Values > 30%), so the ratio of triclopyr to pyribenzoxim is in the range: triclopyr and pyribenzoxim are (2.5-40) to 1.

50-100g a.i./h of triclopyrm²5-10g of a.i./hm with pyribenzoxim²The combined action value (E-E0) of various combinations and combinations is more than 40 percent, so the optimal proportioning range of the triclopyr and the pyribenzoxim is as follows: triclopyr and pyribenzoxim are (5-20) to 1.

50-100g a.i./hm of triclopyr²10g of pyribenzoxim a.i./hm²The combined action value (E-E0) of various combinations is obviously higher than that of other mixture ratios, so the optimal mixture ratio range of the triclopyr and the pyribenzoxim is as follows: triclopyr and pyribenzoxim are (5-10) to 1.

Example 2: determination of safety of triclopyr-pyribenzoxim compound agent on rice

In order to determine the safety of the compound agent of triclopyr-pyribenzoxim on rice, a series of whole plant biological assays are carried out in the artificial climate chamber of the research institute of rice industry and technology at Yangzhou university. Based on the results, the mixture ratio of triclopyr to pyribenzoxim is 10: 1 for the rice safety test.

2.1 test article: japonica rice (Nanjing 9108) and indica rice (Yongyou 2640).

2.2 the setting of the compound dosage of triclopyr-pyribenzoxim: triclopyr + pyribenzoxim: 0+0, 50+5, 100+10, 200+20, 400+40g a.i./hm²

2.3 test methods:

the rice safety test is used for respectively detecting the plants of the tested rice at the leaf stage 3-4, the leaf stage 5-6 and the final tillering stage (before the jointing stage, the main stem begins jointing, and the jointing length is less than 1 cm). In a plastic box with a specification of 22X 15X 10cm, organic soil (pH value 6.5, organic matter content 2.4%) without herbicide is filled, and each box is filled with water till saturation, wherein the soil layer height is about 6 cm. Transplanting the seedlings of japonica rice and indica rice in the 3-4 leaf stage, 5-6 leaf stage and beginning to be jointed into plastic boxes respectively. Transplanting 8 japonica rice and indica rice in 3-4 leaf stage and 5-6 leaf stage into each plastic box, wherein the transplanting depth is uniform, the japonica rice and indica rice survive in shallow water after transplanting, and the water layer is kept 1-2 cm; 1 plant of rice in the initial jointing stage is transplanted in each plastic box, the transplanting depth is uniform, the rice survives in shallow water after transplanting,the aqueous layer was kept 1-2 cm. Each process was repeated with 4 plastic cassettes. After transplanting the rice for 3 days, herbicide treatment is carried out by adopting a stem leaf spraying method, and the same amount of clear water is sprayed on a control group. The spraying is carried out by adopting a walking potential pressure-stabilizing spraying tower of the garden and plant protection college of Yangzhou university, the spraying height is 20cm, the spraying amplitude of a flat fan-shaped nozzle is 50cm, and the pressure is 200 KPa. The amount of the sprayed pesticide liquid corresponds to the amount of field sprayed liquid of 45L water/hm². After 21 days of pesticide application, the fresh weight of the overground part of the rice to be tested in each plastic box is collected and weighed respectively, and the inhibition rate of different treatments on the fresh weight of the overground part of the rice is calculated.

Fresh weight inhibition ratio (control fresh weight-treated fresh weight) ÷ control fresh weight × 100%

2.4 test results

The influence of triclopyr-pyribenzoxim compound agent on the fresh weight of the overground parts of japonica rice and indica rice under different dosage treatment is shown in table 23, and the result shows that various compound dosages of triclopyr-pyribenzoxim according to the proportion of 10: 1 have better safety on rice, even at 440g of a.i./hm²The fresh weight inhibition rate of the rice seedlings under the treatment is still less than 10%.

TABLE 23 inhibition ratio (%)% of triclopyr-pyribenzoxim complex agent to fresh weight of overground part of japonica rice (Nanjing 9108)

*: the dosage is the dosage of triclopyr plus pyribenzoxim.

2.5 conclusion of the test

The mixture ratio of the triclopyr-pyribenzoxim to the triclopyr-pyribenzoxim is between 55 and 440g of a.i./hm²Has better safety from the 3-leaf stage to the pre-jointing stage of the rice under the treatment.

Example 3 measurement of inhibitory Effect of triclopyr-pyribenzoxim combination on resistant weeds

In order to determine the inhibition effect of the compound agent of triclopyr-pyribenzoxim on herbicide-resistant weeds with serious harm to paddy fields, a series of whole plant biological assays are carried out in a phytotron of the research institute of rice industry and technology of Yangzhou university. Based on the previous results, a 10: 1 ratio of triclopyr to pyribenzoxim was used for the experiments.

3.1 weeds tested: anti-cyhalofop-butyl moleplant seed, anti-penoxsulam barnyard grass, conventional moleplant seed and conventional barnyard grass. Cyhalofop-butyl is an aryloxy phenoxy propionate herbicide and has special effect on the malignant weed moleplant seed in the rice field; penoxsulam is a pyrimidine sulfonamide herbicide and has special effect on malignant weeds in rice fields, namely barnyard grass; cyhalofop-butyl and penoxsulam are current herbicides in paddy fields at home. On the other hand, the barnyard grass and the moleplant seed in the paddy field in China are two types of weeds with the most serious occurrence of herbicide resistance. Therefore, the potential of triclopyr pyribenzoxim for resistant weed control was further studied in this example using the anti-cyhalofop-weed-herbicide. In addition, the experiment was performed with conventional Euphorbiae Lathyridis and Echinochloa crusgalli populations for comparison.

3.2 herbicide dose settings:

triclopyr + pyribenzoxim: 50+5, 100+10, 200+20g a.i./hm²

Cyhalofop-butyl: 105g a.i./hm²(recommended maximum dose)

Penoxsulam: 36g a.i./hm²(recommended maximum dose)

3.3 test methods:

a square plastic plant cultivation flowerpot with the specification of 7 multiplied by 7cm is filled with organic soil (pH value is 6.5, organic matter content is 2.4%) without herbicide, and water is added until saturation. And (4) selecting barnyard grass and moleplant seed with plump seeds, and sowing 20 seeds in each small flowerpot. The seeds are covered with a layer of fine soil (the thickness is about 3mm) in the small flowerpot for sowing the barnyard grass, and the small flowerpot for sowing the moleplant seed is not covered with soil. Placing the small flowerpot into a 44X 33X 10cm thickened plastic transfer box (with clear water of 2cm depth added in advance), placing the box in an artificial climate chamber for culturing, illuminating for 14 hours at 28 ℃ and dark for 10 hours at 25 ℃, and keeping a 1-2cm water layer in the transfer box during the test period so that the soil in the small white box can be kept moist by water absorption. After 15 days, the seedlings were set for each small pot, and 12 seedlings with the best growth vigor were kept for each small pot. Each one of which isTreatment 4 small pots were repeated. When the weeds grow to 4-5 leaves, the herbicide is treated by a stem leaf spraying method, and the same amount of clear water is sprayed to a control group. The spraying is carried out by adopting a walking potential pressure-stabilizing spraying tower of the garden and plant protection college of Yangzhou university, the spraying height is 20cm, the spraying amplitude of a flat fan-shaped nozzle is 50cm, and the pressure is 200 KPa. The amount of the sprayed pesticide liquid corresponds to the amount of field sprayed liquid of 45L water/hm²。

After 21 days of pesticide application, the fresh weight of the overground part of the tested weed in each plastic box is collected and weighed respectively, and the inhibition rate of the fresh weight of the overground part of the target weed field by different treatments is calculated.

3.4 test results

The influence of the triclopyr-pyribenzoxim compound agent on the fresh weight of the overground parts of the moleplant seeds and the barnyard grass to be tested under different dose treatment is shown in the table 24, and the result shows that the triclopyr-pyribenzoxim compound agent is 110g of a.i./hm²The inhibition rate of the barnyard grass is more than 85 percent, the inhibition rate of the barnyard grass on the moleplant seed is more than 80 percent, and the inhibition rate of the moleplant seed is 220g of the product of a.i./hm²Completely kill the resistance and the conventional moleplant seed and barnyard grass population, and in addition, the triclopyr-pyribenzoxim is compounded with 220g of a.i./hm²It is highly safe to rice (see Table 23).

TABLE 24 antagonism of different herbicides and fresh weight inhibition rate (%) of aerial parts of conventional Euphorbia lathyris and Echinochloa crusgalli

3.5 conclusion of the test

The triclopyr-pyribenzoxim compound agent can be used for treating resistant barnyard grass and moleplant seed.

Example 4: quick-acting determination of triclopyr-pyribenzoxim compound agent for preventing and controlling weeds

In order to detect the quick action of the triclopyr-pyribenzoxim compound agent for preventing and killing weeds, a series of whole plant biological tests are carried out in the artificial climate chamber of the research institute of the rice industry and technology of Yangzhou universityAnd (4) determining. The previous results show that the triclopyr is 200g a.i./hm²+ pyribenzoxim 20g a.i./hm²Can effectively kill various weeds and is safe to rice, so the research uses the dose as the dose setting of the triclopyr-pyribenzoxim compound agent.

4.1 weeds tested: barnyard grass, semen Euphorbiae, herba Lophatheri, Alternanthera philoxeroides, cyperus rotundus and Iris lactea. Wherein the barnyard grass and the moleplant seed represent the gramineous malignant weeds of the paddy field; the water bamboo leaves and the alternanthera philoxeroides represent broad-leaved malignant weeds in the paddy field; the abnormal-shaped sedges and the Chinese iris represent the malignant weeds in the sedge family of the paddy field. Meanwhile, lophatherum gracile, alternanthera philoxeroides and Chinese iris herb are typical perennial malignant weeds in the rice field; and barnyard grass, moleplant seed and cyperus rotundus L are typical annual malignant weeds in the paddy field.

4.2 herbicide dose settings:

t1: triclopyr 200g a.i./hm²

T2: triclopyr 200g a.i./hm²+ pyribenzoxim 20g a.i./hm²

T3: pyribenzoxim 20g a.i./hm²

T4: clear water control

4.3 test methods:

a square plastic plant cultivation flowerpot with the specification of 7 multiplied by 7cm is filled with organic soil (pH value is 6.5, organic matter content is 2.4%) without herbicide, and water is added until saturation. Selecting barnyard grass with full seeds, moleplant seeds, water bamboo leaves, special-shaped sedges and Chinese iris seeds, and sowing 20 seeds in each small flowerpot. The small flowerpot for sowing barnyard grass is covered with a layer of fine soil (the thickness is about 3mm) on the seeds, and the small flowerpot for sowing moleplant seed, water bamboo leaf, Chinese iris and abnormal sedge is not covered with soil. The alligator alternanthera seedlings are obtained by asexual propagation, 5 sections of alligator alternanthera rhizomes with buds are filled in each small flowerpot, each root-shaped stem is 4cm long, and a layer of fine soil (the thickness is about 5mm) is covered. Placing the small flowerpot into a thickened plastic transfer box (with the depth of 2cm added in advance) with the thickness of 44X 33X 10cm, placing the box in an artificial climate chamber for culturing, illuminating for 14 hours at the temperature of 28 ℃ and dark for 10 hours at the temperature of 25 ℃, and keeping a water layer with the thickness of 1-2cm in the transfer box during the test period so as to ensure that the soil in the small white box is kept moist by absorbing water. After 15 days, the seedlings of each small flowerpot are set, 12 seedlings with the best growth vigor are reserved in each small flowerpot of the barnyard grass, the moleplant seed, the Chinese iris and the abnormal sedge, and 6 seedlings with the best growth vigor are reserved in each small flowerpot of the water bamboo leaf. After the alligator alternanthera is cultured in the flowerpot for 15 days, 3 seedlings with the best growth vigor are reserved in each small flowerpot. Each treatment was repeated with 4 small pots.

Carrying out herbicide treatment by adopting a stem and leaf spraying method when barnyard grass, moleplant seed, abnormal sedge and Iris lactea seedlings grow to 4-5 leaf stage; the lophatherum gracile and the alligator alternanthera are subjected to herbicide treatment by adopting a stem and leaf spraying method when growing to 6 leaves, and the same amount of clear water is sprayed on a control group. The spraying is carried out by adopting a walking potential pressure-stabilizing spraying tower of the garden and plant protection college of Yangzhou university, the spraying height is 20cm, the spraying amplitude of a flat fan-shaped nozzle is 50cm, and the pressure is 200 KPa. The amount of the sprayed pesticide liquid corresponds to the amount of field sprayed liquid of 45L water/hm². And after 7 days, 15 days and 45 days of pesticide application, respectively collecting and weighing the fresh weight of the overground part of the tested weed in each small flowerpot, and calculating the inhibition rate of the fresh weight of the overground part.

4.4 test results

The fresh weight inhibition rates for various weeds at 7 days, 15 days and 45 days after the application of the herbicides of the different treatments are shown in tables 25, 26 and 27. The result shows that the quick-acting performance of the herbicide can be greatly improved by compounding the triclopyr and the pyribenzoxim, particularly after the herbicide is applied for 7 days. The results in Table 25 show that the inhibition rate after 7 days of application is low, the control effect on gramineous weeds and cyperaceae weeds is not high under the single-agent treatment of the two agents, and the synergistic effect is great when the two agents are used in a compounding way. The results of 15 days after the application of the herbicide are shown in tables 26 and 27, and the results also show that the combination of triclopyr and pyribenzoxim can greatly accelerate the drug effect of pyribenzoxim, and the combination of triclopyr and pyribenzoxim can obviously reduce the dosage of the herbicide.

TABLE 25 fresh weight inhibition (%)

T1: triclopyrAcetic acid 200g a.i./hm²(ii) a T2: triclopyr 200g a.i./hm²+ pyrimidine oxime monoether 20g a.i./hm²(ii) a T3: pyribenzoxim 20g a.i./hm².

TABLE 26 fresh weight inhibition (%)

T1: triclopyr 200g a.i./hm 2; t2: 200g of triclopyr a.i./hm2+ 20g of pyribenzoxim a.i./hm 2; t3: pyribenzoxim 20g a.i./hm2.

TABLE 27 fresh weight inhibition (%) -of the various herbicides on the weeds tested 45 days after application

4.5 conclusion of the test

The combination of triclopyr and pyribenzoxim can greatly improve the drug effect, and a large amount of target weeds die after 7 days of drug application. The rice seedling stage gets rid of weed competition as soon as possible, enough tillering and node pulling and row sealing are formed as soon as possible (competitive advantage for weeds is completely established), and the method is the basis of high yield of rice. Therefore, the test result shows that the triclopyr-pyribenzoxim compound has great application value.

Claims

1. A weeding composition is characterized by comprising triclopyr and pyribenzoxim in a weight ratio of (2.5-40) to 1, and the weeding composition can prevent and control weeds in a rice field, wherein the weeds comprise gramineous weeds, broadleaf weeds, cyperaceae weeds and perennial malignant weeds, and the perennial malignant weeds comprise lophatherum gracile, alternanthera philoxeroides, edible tulip and Chinese iris.

2. The weeding composition according to claim 1, wherein the weight ratio of the triclopyr to the pyribenzoxim is (5-20) to 1.

3. The weeding composition according to claim 1, wherein the weight ratio of the triclopyr to the pyribenzoxim is (5-10) to 1.

4. The application of the weeding composition according to claim 1 in preventing and controlling paddy field weeds is characterized in that the weeding composition is sprayed on stems and leaves of the paddy field weeds at the 3-6 leaf stage and before the 3-leaf stage to the jointing stage of the paddy field weeds, and the weeds are resistant weeds.