Application of DMNT structure modified product as herbicide

Abstract

The invention provides application of a DMNT structure modified product as a herbicide. The structural formula of the DMNT structure modified product is # imgabs0, wherein R substituent is one of hydroxyl, halogen, aldehyde group, carboxyl, ester group, ether group and amino. DMNT is used as an initial raw material, molecules of DMNT are subjected to structural modification, a series of modified products are synthesized, systematic herbicidal activity test on the synthesized DMNT modifier and crop safety test on corn prove that the DMNT modifier has a stronger poison effect on weeds, and the substance has no toxic effect on crops and has a good application prospect. According to the invention, DMNT is taken as a research object, and the obtained DMNT modifier is a novel, efficient and environment-friendly natural herbicide and has important significance on prevention and control of crop weeds.

Description

Technical Field

[0001] The invention relates to the technical field of pesticide manufacturing, and in particular to application of a DMNT structure-modified product as a herbicide. Background Art

[0002] Weeds are one of the most serious hazards in agricultural production and will have a serious impact on the quality and yield of crops. Echinochloa crus-galli, a plant of the genus Echinochloa in the Poaceae family, is the most important malignant weed in my country's fields. It has great harm to crops such as rice, corn, beans, potatoes, cotton, cereals and vegetables. Setaria viridis has a well-developed root system and can absorb a large amount of soil moisture and nutrients, affecting the utilization of light energy and photosynthesis of crops, thereby limiting the growth of crops. In addition, Setaria viridis often serves as an intermediate host for pests and diseases, spreading diseases and pests, further affecting the yield and quality of crops. The dicotyledonous plant Portulaca oleracea is a major weed in autumn-ripening dry crop fields. It is a serious threat to corn fields, soybean fields and cotton fields and is a global weed. From June to September when Portulaca oleracea reproduces in large numbers, its coverage reaches 80%, which will cause a nearly 90% reduction in leafy vegetable yields, almost a total crop failure. Ramie mainly harms crops such as corn, cotton, beans, and vegetables. It also grows in wasteland and roadsides, easily forming a single dominant community and endangering biodiversity.

[0003] Herbicides have attracted widespread attention since the late 19th century. According to statistics from the Food and Agriculture Organization of the United Nations, the widespread use of herbicides has increased global food production by more than 10%, playing a vital role in increasing food production. Since the mid-20th century, the application of chemical synthetic pesticides has gradually become one of the main methods of weed control in agricultural production. However, chemical synthetic herbicides are generally highly toxic and difficult to biodegrade. Excessive use will cause serious harm to the environment and easily cause weeds to develop resistance, resulting in a variety of weeds in the field, rapid population succession, and high resistance levels. Under the new situation, the development of new environmentally friendly natural herbicides has received increasing attention.

[0004] Monoterpenoids in plant essential oils have allelopathic effects and can inhibit the growth of surrounding weeds and the germination of seeds. Natural products and their derivatives play a vital role in the development of new herbicides. Due to their unique sources, natural products are usually less harmful and safer. The terpene homologue (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT for short) is a class of natural metabolites widely found in plants such as rice, corn, and cotton. It can repel and prevent insects and plays an important role in the plant's anti-insect defense response, but its herbicidal activity has not been reported. Summary of the invention

[0005] The technical problem to be solved by the present invention is how to provide a highly efficient and environmentally friendly natural herbicide.

[0006] The present invention solves the above technical problems through the following technical means:

[0007] The present invention provides an application of a DMNT structure-modified product as a herbicide, wherein the structural formula of the DMNT structure-modified product is The R substituent is one of a hydroxyl group, a halogen group, an aldehyde group, a carboxyl group, an ester group, an ether group, and an amine group.

[0008] Beneficial effects: The present invention uses DMNT as a starting material, modifies the structure of its molecule, and synthesizes a series of modified products. By conducting a systematic herbicidal activity test on the synthesized DMNT modifier and a crop safety test on corn, it is proved that the DMNT modifier has a stronger toxic effect on weeds, and the substance has no toxic effect on crops, is green, safe and environmentally friendly. The present invention uses DMNT as a research object, and the DMNT modifier obtained is a new type of highly efficient and environmentally friendly natural herbicide, which is of great significance for the prevention and control of weeds on crops.

[0009] Preferably, the R substituent is -OH, -OAc, -OBn, -OMe, One of them.

[0010] Preferably, the DMNT structural modification product is

[0011] Preferably, the DMNT structural modification product is the only active ingredient of the herbicide.

[0012] Preferably, the DMNT structure-modified product is mixed with an organic solvent before use.

[0013] Preferably, the organic solvent is acetone.

[0014] Preferably, the DMNT structurally modified product achieves the purpose of weed control by inhibiting the germination of weed seeds.

[0015] Preferably, the weeds include one or more of barnyard grass, foxtail grass, purslane and velvetleaf.

[0016] Preferably, the herbicide is an emulsion, and the concentration of the DMNT structure-modified product is 100-300 μg / mL.

[0017] The advantages of the present invention are:

[0018] DMNT is a natural secondary metabolite of plant-derived terpenes. The present invention first discovered that DMNT has herbicidal activity, and used the plant-derived terpenoid substance DMNT as the starting material to modify its molecule structure to obtain a series of modified products. By systematically testing the herbicidal activity of DMNT and the synthesized DMNT modifications, the toxic effect of DMNT on weeds was confirmed, and a modified product with better herbicidal effect than DMNT was obtained. Studies have shown that DMNT modifications have stronger toxic effects on barnyard grass, foxtail grass, purslane, and velvetleaf, and achieve the purpose of weed control by inhibiting the germination of weed seeds. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a synthetic route for preparing DMNT modified products using DMNT as a starting material in Example 1;

[0020] Figure 2 This is a graph showing the inhibition of barnyard grass sprout growth by representative compounds 1 and 2 at a concentration of 100 μg / mL in Example 2; wherein A is a blank control treatment, B is a compound 1 treatment, and C is a compound 2 treatment;

[0021] Figure 3 This is a graph showing the inhibition of barnyard grass sprout growth by representative compounds 1 and 2 at a concentration of 300 μg / mL in Example 2; wherein A is a blank control treatment, B is a compound 1 treatment, and C is a compound 2 treatment;

[0022] Figure 4 This is a graph showing the inhibition of Setaria foetida bud growth by representative compounds 1 and 3a at a concentration of 100 μg / mL in Example 2; wherein A is a blank control treatment, B is a compound 1 treatment, and C is a compound 3a treatment;

[0023] Figure 5 This is a graph showing the inhibition of Setaria foetida bud growth by representative compounds 1 and 3a at a concentration of 300 μg / mL in Example 2; wherein A is a blank control treatment, B is a compound 1 treatment, and C is a compound 3a treatment;

[0024] Figure 6 This is a graph showing the inhibition of purslane sprout growth by representative compounds 1 and 2 at a concentration of 100 μg / mL in Example 2; wherein A is a blank control treatment, B is a compound 1 treatment, and C is a compound 2 treatment;

[0025] Figure 7 This is a graph showing the inhibition of purslane sprout growth by representative compounds 1 and 2 at a concentration of 300 μg / mL in Example 2; wherein A is a blank control treatment, B is a compound 1 treatment, and C is a compound 2 treatment;

[0026] Figure 8This is a graph showing the inhibition of Abutilon velutipes bud growth by representative compounds 1 and 3a at a concentration of 100 μg / mL in Example 2; wherein A is a blank control treatment, B is a compound 1 treatment, and C is a compound 3a treatment;

[0027] Fig. 9 This is a graph showing the inhibition of Abutilon velutipes bud growth by representative compounds 1 and 3a at a concentration of 300 μg / mL in Example 2; wherein A is a blank control treatment, B is a compound 1 treatment, and C is a compound 3a treatment;

[0028] Fig.10 is the growth inhibition rate of DMNT and its modifications on barnyard grass sprouts in Example 2;

[0029] Fig.11 is the growth inhibition rate of DMNT and its modifications on Setaria viridis buds in Example 2;

[0030] Fig.12 is the growth inhibition rate of DMNT and its modifications on purslane sprouts in Example 2;

[0031] Fig.13 is the growth inhibition rate of DMNT and its modifications on Abutilon buds in Example 2;

[0032] Fig.14 This is the corn growth chart in Example 3; A is the blank control treated for 14 days, and B is 1000g / hm 2 Compound 2 was treated for 14 days, C was 1000 g / hm 2 Compound 3a was treated for 14 days;

[0033] Fig.15 is the H NMR spectrum of compound 3a in Example 1 of the present invention;

[0034] Fig.16 It is the NMR carbon spectrum of compound 3a in Example 1 of the present invention. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] Unless otherwise specified, the test materials and reagents used in the following examples can be obtained from commercial sources.

[0037] If no specific techniques or conditions are specified in the examples, they can be carried out according to the techniques or conditions described in the literature in the art or according to the product instructions.

[0038] Example 1

[0039] The synthetic route of DMNT modification in this example is referenced to Figure 1 ;

[0040] (1) Synthesis of Compound 2

[0041] Selenium oxide (121.8 mg) and salicylic acid (1 g) were dissolved in dichloromethane (75 mL), and compound 1 (5.5 g) and tert-butyl peroxide (70% by volume aqueous solution, 17.8 mL) were added in sequence, and the mixture was reacted at 35°C for 24 h. The reaction process was tracked by TCL. After the reaction was completed, heating was stopped, and salicylic acid was removed by washing with saturated sodium bicarbonate solution. The organic phase was collected and dried with anhydrous sodium sulfate, and the organic solvent was evaporated to obtain a crude product, which was then separated and purified by silica gel column chromatography to obtain a light yellow oily compound 2. The NMR data of compound 2 are as follows: 1 H NMR (600MHz, CDCl3) δ6.59-6.53(m,1H),5.86(d,J=10.8Hz,1H),5.40(t,J=6.6Hz,1H),5.10(d,J=16.8Hz,1H) ,4.99(d,J=10.2Hz,1H),3.97(s,2H),2.19(t,J=6.6Hz,2H),2.11(t,J=8.4Hz,2H),1.76(s,3H),1.66(s,3H).

[0042] (2) Synthesis of compound 2a

[0043] Compound 2 (166.26 mg) was dissolved in anhydrous THF (4 mL) under ice bath conditions, and sodium hydride (96 mg) was slowly added in batches. The ice bath was removed, and the reaction was carried out at room temperature for 10 min, and then iodomethane (124 μL) was slowly added dropwise to the solution. After the reaction was carried out at room temperature for 30 min, it was refluxed overnight. After TLC detection, the raw material point disappeared, and water was added to quench. The organic phase was extracted with ethyl acetate, dried and concentrated to obtain a crude product, and then separated and purified by silica gel column chromatography to obtain a transparent oily compound 2a (153.3 mg, yield 85%). The NMR data of compound 2a are as follows: 1H NMR (600MHz, CDCl3) δ6.60-6.54(m,1H),5.86(d,J=10.8Hz,1H),5.40(t,J=7.8Hz,1H),5.10(d,J=17.4Hz,1H),4.9 9(d,J=9.6Hz,1H),3.78(s,2H),3.26(s,3H),2.20(t,J=8.4Hz,2H),2.12(t,J=9Hz,2H),1.76(s,3H),1.64(s,3H).

[0044] (3) Synthesis of compound 2b

[0045] Compound 2 (166.26 mg), triethylamine (278 μL), and acetic anhydride (178 μL) were dissolved in DCM (4 mL) and reacted at room temperature for 2 h. After the reaction was completed, the solvent was evaporated to obtain a crude product, which was then separated and purified by silica gel column chromatography to obtain a light yellow oily compound 2b (179.1 mg, yield 86%). The NMR data of compound 2b are as follows: 1 H NMR (600MHz, CDCl3) δ6.60-6.53(m,1H),5.86(d,J=10.8Hz,1H),5.46(t,J=7.8Hz,1H),5.11(d,J=16.8Hz,1H),5.00 (d,J=10.2Hz,1H),4.45(s,2H),2.19(t,J=8.4Hz,2H),2.11(t,J=7.8Hz,2H),2.06(s,3H),1.76(s,3H),1.65(s,3H).

[0046] (4) Synthesis of compound 2c

[0047] Compound 2 (166.26 mg) was reacted with NaH (230.4 mg) in an ice bath for 5 minutes, and then BnBr (166.26 mg) was added and reacted overnight at room temperature. After the reaction was completed, the solvent was evaporated to obtain a crude product, which was then separated and purified by silica gel column chromatography to obtain a light yellow oily compound 2c (190 mg, yield 92%). The NMR data of compound 2c are as follows: 1H NMR (600MHz, CDCl3) δ7.35(s,4H),7.29(s,1H),6.62-6.53(m,1H),5.89(d,J=10.8Hz,1H),5.44(t,J=7.8Hz,1H),5.12(d,J=16.8Hz,1H) ,5.01(d,J=10.2Hz,1H),4.45(s,2H),3.91(s,2H),2.23(t,J=7.8Hz,2H),2.15(t,J=6.6Hz,2H),2.06(s,3H),1.78(s,3H),1.70(s,3H).

[0048] (5) Synthesis of Compound 3

[0049] First, triphosgene (908 mg) was dissolved in dichloromethane (30.0 mL), and compound 2 (1.5 g) was slowly added under ice bath. Then, a mixed solution of triethylamine (1250 μL) and DCM (10.0 mL) was added dropwise, and the mixture was reacted at room temperature for 3 h. After the reaction was completed, the solvent was evaporated to obtain a crude product, which was separated and purified by silica gel column chromatography to obtain a transparent oily compound 3 (1.2 g, yield 58.3%). The NMR data of compound 3 are as follows: 1 H NMR (600MHz, CDCl3) δ6.59-6.53(m,1H),5.86(d,J=11.4Hz,1H),5.52(t,J=7.2Hz,1H),5.12(d,J=16.8Hz,1H) ,5.00(d,J=10.2Hz,1H),4.01(s,2H),2.19(t,J=8.4Hz,2H),2.13(t,J=8.4Hz,2H),1.76(s,3H),1.74(s,3H).

[0050] (6) Synthesis of Compound 3a

[0051] Morpholine (46 μL) and triethylamine (184 μL) were dissolved in anhydrous DMF (2 mL), and then compound 3 (100 mg) was slowly added to the solution under ice bath conditions, reacted at room temperature for 30 min, and then refluxed at 60 ° C overnight. TCL tracked the reaction process. After the reaction was completed, it was washed with water and saturated sodium chloride solution for 3 times, and the organic matter was extracted with ethyl acetate and concentrated. The initial product was purified by column chromatography to obtain brown oily compound 3a (120.1 mg, yield 95%). The NMR spectrum of compound 3a is shown as follows Fig.15 and 16 The specific data are as follows: 1H NMR (600MHz, CDCl3) δ6.58-6.51(m,1H),5.83(d,J=10.8Hz,1H),5.28(t,J=7.8Hz,1H),5.07(d,J=16.8Hz,1H),4.97(d,J=1 0.2Hz,1H),3.67(s,4H),2.80(s,2H),2.31(s,4H),2.18(t,J=7.8Hz,2H),2.10(t,J=7.8Hz,2H),1.75(s,3H),1.63(s,3H).

[0052] (7) Synthesis of compound 3b

[0053] Diethylamine (54.4 μL) and triethylamine (184 μL) were dissolved in anhydrous DMF (2 mL), and then compound 3 (100 mg) was slowly added dropwise to the solution under ice bath conditions, reacted at room temperature for 30 min, and then refluxed at 60 ° C overnight. TCL tracked the reaction progress. After the reaction was completed, it was washed with water and saturated sodium chloride solution for 3 times, and the organic matter was extracted with ethyl acetate and concentrated. The initial product was purified by column chromatography to obtain a colorless oil compound 3b (81.3 mg, yield 68%). The NMR data of compound 3b are as follows: 1 H NMR (600MHz, CDCl3) δ6.59-6.53(m,1H),5.84(d,J=9.6Hz,1H),5.29(t,J=5.4Hz,1H),5.09(d,J=16.8Hz,1H),4.98(d,J=10.2Hz,1H) ,2.91(s,2H),2.53(dd,J=14.4Hz,2H),2.19(t,J=7.8Hz,2H),2.11(t,J=8.4Hz,2H),1.75(s,3H),1.66(s,3H),1.02(t,J=7.2Hz,6H).

[0054] (8) Synthesis of compound 3c

[0055] p-Toluidine (56.6 mg) and triethylamine (184 μL) were dissolved in anhydrous DMF (2 mL), and then compound 3 (100 mg) was slowly added dropwise to the solution under ice bath conditions, reacted at room temperature for 30 min, and then refluxed at 60 ° C overnight. TCL tracked the reaction process. After the reaction was completed, it was washed with water and saturated sodium chloride solution for 3 times, and the organic matter was extracted with ethyl acetate and concentrated. The initial product was purified by column chromatography to obtain brown oily compound 3c (74.5 mg, yield 54%). The NMR data of compound 3c are as follows: 1H NMR (600MHz, CDCl3) δ6.98(d,J=8.4Hz,1H),6.62-6.57(m,1H),6.55(d,J=8.4Hz,2H),5.86(d,J=10.8Hz,1H),5.42(t,J=7.2Hz,1H),5.12( d,J=16.8Hz,1H),5.01(d,J=10.2Hz,1H),3.62(s,2H),2.24(s,3H),2.20(t,J=7.8Hz,2H),2.11(t,J=8.4Hz,2H),1.77(s,3H),1.68(s,3H).

[0056] (9) Synthesis of compound 3d

[0057] n-Butylamine (41.51 μL) and triethylamine (184 μL) were dissolved in anhydrous DMF (2 mL), and then compound 3 (100 mg) was slowly added dropwise to the solution under ice bath conditions, reacted at room temperature for 30 min, and then refluxed at 60 ° C overnight. TCL tracked the reaction process. After the reaction was completed, it was washed with water and saturated sodium chloride solution for 3 times, and the organic matter was extracted with ethyl acetate and concentrated. The initial product was purified by column chromatography to obtain a transparent oily compound 3d (86.1 mg, yield 72%). The NMR data of compound 3d are as follows: 1 H NMR (600MHz, CDCl3) δ6.60-6.54(m,1H),5.86(d,J=10.8Hz,1H),5.25(t,J=7.2Hz,1H),5.09(d,J=14.4Hz,1H),4.98(d,J=10.8Hz ,1H),2.74(s,2H),2.22-2.15(m,4H),2.10(t,J=8.4Hz,2H),1.76(s,3H),1.61(s,3H),1.43-1.26(m,5H),0.88(t,J=7.2Hz,2H).

[0058] Example 2

[0059] The toxic effects of DMNT modifications on monocotyledonous weeds Echinochloa crusgalli and Setaria viridis and dicotyledonous weeds Portulaca oleracea and Abutilon velvetleaf were tested.

[0060] (1) Dissolve DMNT and its modifications in acetone and dilute them to concentrations of 100 μg / mL and 300 μg / mL, respectively, for later use.

[0061] (2) The experiment used 2% acetone as the blank control, 2,4-D as the positive control, DMNT treatment and 8 different modifiers as the experimental groups, and each group had 6 parallel replicates.

[0062] (3) Seed germination:

[0063] 1. Barnyard grass: Soak the seeds in a 0.2% sodium hypochlorite solution for 15 minutes, wash with sterile water three times to remove the residual sodium hypochlorite solution, and culture the treated seeds in a 28°C light incubator for 1-2 days. Observe regularly, select the seeds that have just started to turn white, wash them with sterile water and set aside.

[0064] 2. Setaria: Soak the seeds in 40mmol / L calcium chloride solution for 15 minutes, wash the residual calcium chloride solution three times with sterile water, and let it stand in a culture dish lined with filter paper for 20 minutes; then soak it in 200mg / L gibberellin solution at 20℃ for 12h, then wash it with sterile water, and culture the treated seeds in a 28℃ light incubator for 1-2 days. Observe regularly, select the seeds that have just started to turn white, wash them with sterile water and set them aside.

[0065] 3. Portulaca oleracea: Soak the seeds in 40mmol / L calcium chloride solution for 15 minutes, then ultrasonically vibrate for 2 minutes, and wash the residual calcium chloride solution three times with sterile water; then soak in 200mg / L gibberellin solution for 12h, then wash with sterile water, and culture the treated seeds in a 28℃ light incubator for 1-2 days, observe regularly, select the seeds that have just started to turn white, wash them with sterile water and set aside.

[0066] 4. Ramie: Soak the seeds in 60℃ water for 30 minutes, then soak them in 40mmol / L calcium chloride solution for 12 hours; take them out and wash them with sterile water, place the treated seeds in a 28℃ light incubator for 1-2 days, observe them regularly, select the seeds that have just started to turn white, wash them with sterile water and set them aside.

[0067] (4) Place a qualitative filter paper with a diameter of 9 cm on a petri dish in advance (both the filter paper and the petri dish must be sterilized and dried before use), use a pipette to slowly drip 5 mL of the sample into the petri dish, and add an equal volume of 0.2% acetone solution as a blank control. Select the weed seeds that have whitened and place them evenly in the petri dish (20 seeds per dish), and place them in a constant temperature climate incubator at 28°C and 50% relative humidity for 1-2 days.

[0068] (5) measuring the length of young shoots and expressing the herbicidal activity of the samples as the average sprout growth inhibition rate;

[0069] The inhibition rate was calculated according to the following formula:

[0070] Where: R is the inhibition rate of the sample to be tested on the sprout growth; L0 is the sprout length under blank control culture, in cm; L1 is the sprout length under different concentrations of the sample to be tested solution culture, in cm.

[0071] Depend on Figure 2-13 It can be seen that DMNT and its DMNT modifications have different degrees of inhibitory effects on weeds. The growth inhibition rate of DMNT on barnyard grass sprouts was 21.9% at a concentration of 100μg / mL, and the growth inhibition rate of DMNT on barnyard grass sprouts was 56.6% at a concentration of 300μg / mL. It has certain herbicidal activity itself; after structural modification, the herbicidal activity of DMNT modifications is enhanced. Among them, compound 2 has a growth inhibition rate of 90% on barnyard grass sprouts at a concentration of 100μg / mL, and completely inhibits the growth of barnyard grass sprouts at a concentration of 300μg / mL.

[0072] The growth inhibition rate of DMNT on Setaria buds was 26.5% at a concentration of 100 μg / mL, and 59.2% at a concentration of 300 μg / mL. After structural modification, the herbicidal activity of the DMNT modified product was further enhanced. Among them, the growth inhibition rate of compound 3a on Setaria buds was 82.5% at a concentration of 100 μg / mL, and 88.9% at a concentration of 300 μg / mL.

[0073] The growth inhibition rate of DMNT on purslane buds was 12.3% at a concentration of 100 μg / mL, and 36.2% at a concentration of 300 μg / mL, which was relatively low; after structural modification, the herbicidal activity of the compound was further enhanced. Among them, the growth inhibition rate of compound 2 on purslane buds was 93.3% at a concentration of 100 μg / mL, and 96.6% at a concentration of 300 μg / mL.

[0074] The growth inhibition rate of DMNT on Abutilon buds was 39.8% at a concentration of 100 μg / mL, and 56.2% at a concentration of 300 μg / mL; after structural modification, the herbicidal activity of the compound was further enhanced. Among them, the growth inhibition rate of compound 3a on Abutilon buds was 88.6% at a concentration of 100 μg / mL, and 94% at a concentration of 300 μg / mL.

[0075] In summary, it is shown that DMNT modifications have good herbicidal activity, which provides a new idea for the development of new, efficient, and environmentally friendly natural herbicides.

[0076] Example 3

[0077] In this example, compound 2 and compound 3a with good herbicidal activity were selected to conduct crop safety test on corn.

[0078] (1) Place a certain amount of vermiculite in a tray and moisten it with water. Sow B73 wild-type corn seeds, cover them with vermiculite to a depth of 0.6 cm, moisten them with water, place them in a light incubator, and water them with a certain amount of clean water every day to ensure normal growth of the corn.

[0079] (2) After germination, the plants were transferred to small pots of 5 cm and the soil was sprayed with a solution of the compound to be tested at a concentration of 1000 g / hm2 using a laboratory belt sprayer. 2 Water was selected as blank control and 2,4-D as positive control, and each treatment was repeated 3 times.

[0080] (3) Transfer to a greenhouse and add water by infiltration irrigation from the bottom of the pots. Regularly observe and record the growth status of the crops after treatment. After 14 or 21 days of treatment, use visual inspection to investigate and record the effects of the corresponding pesticides on corn.

[0081] Depend on Fig.14 It can be seen that compared with the blank control treated with compounds 2 and 3a for 14 days, the corn did not show albinism, yellowing, new leaf deformity, wilting, dehydration, dwarfing, clustering and other phenomena. Therefore, the DMNT modifier has no toxic effect on the growth of crops (corn), is highly safe, and is green and environmentally friendly, laying the foundation for the later development of plant-derived terpene compound herbicides.

[0082] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. Application of a DMNT structurally modified product as a herbicide, characterized in that: The structural formula of the DMNT structure-modified product is The R substituent is one of a hydroxyl group, an aldehyde group, a carboxyl group, an ester group, an ether group, and an amine group.

2. The use of the DMNT structural modification product according to claim 1 as a herbicide, characterized in that: The R substituent is -OH, -OAc, -OBn, -OMe, One of them.

3. The use of the DMNT structural modification product according to claim 2 as a herbicide, characterized in that: The DMNT structure-modified product is 4. The use of the DMNT structural modification product according to claim 1 as a herbicide, characterized in that: The DMNT structure-modified product is the sole active ingredient of the herbicide.

5. The use of the DMNT structural modification product according to claim 4 as a herbicide, characterized in that: The DMNT structure-modified product is mixed with an organic solvent before use.

6. Use of the DMNT structural modification product according to claim 5 as a herbicide, characterized in that: The organic solvent is acetone.

7. Use of the DMNT structural modification product according to claim 1 as a herbicide, characterized in that: The DMNT structure-modified product achieves the purpose of weed control by inhibiting the germination of weed seeds.

8. Use of the DMNT structural modification product according to claim 7 as a herbicide, characterized in that: The weeds include one or more of barnyard grass, foxtail grass, purslane and velvetleaf.

9. The use of the DMNT structural modification product according to claim 1 as a herbicide, characterized in that: The herbicide is an emulsion, and the concentration of the DMNT structure-modified product is 100-300 μg / mL.

Images