Application of phytic acid in rice resistance to leaf spot disease

Abstract

The application discloses application of phytic acid in rice resistance to leaf spot disease of sesamum indicum, and belongs to the technical field of bioengineering. The phytic acid can significantly inhibit spore germination and mycelium growth of rhynchosporium oryzae, and can significantly change mycelium cell morphology of the rhynchosporium oryzae, directly inhibits growth of the rhynchosporium oryzae; in addition, after the rice is sprayed with the phytic acid, the expression level of important disease course related protein coding genes OsPR1a , OsPR5 and OsPR10a in the rice can be significantly induced; the phytic acid is an endogenous compound of the rice, has a natural advantage in environmental compatibility, meets the requirements of green agriculture and sustainable development, and provides a new active substance for prevention and treatment of the leaf spot disease of the sesamum indicum.

Description

Technical Field

[0001] This invention relates to the field of bioengineering technology, specifically to the application of a phytic acid in the resistance of rice to sesame leaf spot disease. Background Technology

[0002] Rice is an important food crop, with more than half of the world's population relying on it as their staple food. As the world's population grows, the demand for rice continues to increase. Therefore, high and stable rice yields are crucial to people's livelihoods and national food security. However, the characteristics of large-scale agricultural production, such as monoculture and lack of genetic diversity, make rice more susceptible to various pathogenic microorganisms during its growth and development. Currently, about 70%-80% of crop diseases in production are caused by fungal pathogens, which seriously affect the yield and quality of rice and restrict the green production of rice.

[0003] Rice leaf spot disease is caused by *Helicobacter pylori* (… Bipolaris oryzae This disease is caused by a saprophytic fungus. Rice sesame leaf spot can occur throughout the entire growth period of rice, with leaf infection being the most common. Lesions resembling sesame seeds are scattered on the leaves. In severe cases, the lesions gradually enlarge and merge, forming large, irregularly shaped lesions. The leaves gradually wither from the tip downwards, eventually leading to the death of the entire plant. Symptoms in the panicle include brown or grayish-brown grains, resulting in panicle dieback. Sesame leaf spot is a global rice disease, often considered a typical "stress-induced" or "malnutrition-induced" disease. Millions of hectares of rice fields worldwide are affected by sesame leaf spot each year, especially in poor soils and areas lacking water and fertilizer. The disease is particularly severe under certain conditions; with climate warming, high temperature and drought stress are becoming more frequent, and the occurrence of rice sesame leaf spot disease is gradually intensifying, generally causing yield losses of 10% to 30%, and under certain conditions, losses may even exceed 50%. As one of the most common diseases affecting rice, rice sesame leaf spot disease has been poorly studied, and research data on resistance genes in rice, their resistance molecular mechanisms, and resistance inducers are also very scarce. Therefore, identifying resistance-regulating genes and inducers for rice sesame leaf spot disease and elucidating the resistance mechanism are of great significance for the green control of rice sesame leaf spot disease and disease-resistant breeding.

[0004] Inositol-1,2,3,4,5,6-hexaphosphate (IP6), also known as phytic acid (PA), is the main storage form of phosphorus (P) in plants. It is abundant in cereals, legume seeds, and nuts, accounting for 65%–85% of total seed phosphorus and approximately 1.5% of dry weight. In most cereals, the phytic acid molecule carries six negatively charged phosphate groups, allowing it to chelate zinc ions (Zn²⁺). + ), ferrous ions (Fe²⁺) + ), calcium ions (Ca²) + ) and magnesium ions (Mg²)+ Phytate is formed from various mineral cations, including inositol, phosphorus, and mineral cations. During seed germination, endogenous phytase is activated, degrading phytate and releasing inositol, phosphorus, and mineral cations for seedling growth. Seeds are the main storage organ for phytate, while leaves, roots, and other parts also synthesize and accumulate phytate. Rice... OsITPK6 The gene encodes inositol 1,3,4-triphosphate 5 / 6-kinase 6, which plays an important role in the biosynthesis of phytic acid in rice. Summary of the Invention

[0005] To solve or partially solve the problems existing in related technologies, the present invention provides an application of phytic acid in rice resistance to sesame leaf spot disease, the specific steps of which are: spraying phytic acid on the surface of rice leaves.

[0006] The structural formula of phytic acid described in this invention is: Formula I.

[0007] Preferably, the concentration of phytic acid in this invention is 0.5-2 mg / mL.

[0008] The present invention has the following beneficial effects: (1) This invention proposes a new use of phytic acid in regulating rice resistance to sesame leaf spot disease. Through in vitro antibacterial experiments, it is demonstrated that phytic acid has significant growth inhibitory activity against rice spores, including inhibiting spore germination and mycelial growth, providing a new active substance for the prevention and control of sesame leaf spot disease.

[0009] (2) This invention provides a clear theoretical basis and genetic resources for improving the resistance of rice to sesame leaf spot disease by using genetic engineering methods.

[0010] (3) Phytic acid, as an endogenous compound of rice, has a natural advantage in environmental compatibility and meets the requirements of green agriculture and sustainable development. Attached Figure Description

[0011] Figure 1 This refers to the phytic acid content in rice ZH11 after inoculation with *Helicobacter pylori* in Example 1 of this invention.

[0012] Figure 2 In Example 2 of this invention, after infection with *Helicobacter pylori*, rice ZH11... OsITPK6 The transcriptional level of genes.

[0013] Figure 3 This is in embodiment 3 of the present invention OsITPK6 Phytic acid content and disease incidence in gene knockout mutants, among which Figure 3 (a) is OsITPK6 Disease incidence after inoculation of gene knockout mutants with *Helicobacter pylori* (rice spores), scale bar = 1 cm. Figure 3 (b) is OsITPK6 Area of ​​lesions after inoculation of gene knockout mutants with rice spores Figure 3 (c) is OsITPK6 Results of phytic acid content detection in gene knockout mutants.

[0014] Figure 4 This is the result of the effect of phytic acid on the mycelial growth of *Helicobacter pylori* in Example 4 of the present invention; wherein, Figure 4 (a) The growth of *Helicobacter pylori* colonies after the addition of phytic acid and hydrochloric acid. Scale bar = 1 cm. Figure 4 (b) shows the comparison of the inhibition rates of phytic acid and hydrochloric acid on the mycelial growth of *Helicobacter pylori*.

[0015] Figure 5 This is the result of the effect of phytic acid on the germination of rice spores in Example 4 of the present invention; wherein, Figure 5 (a) Germination of *Helicobacter pylori* spores after the addition of phytic acid and hydrochloric acid, scale bar = 25 μm. Figure 5 (b) shows the effects of phytic acid and hydrochloric acid on the germination rate of rice spores.

[0016] Figure 6 This is the result of the effect of phytic acid on the hyphal morphology of rice pyrenoidosa in Example 4 of the present invention, scale bar = 25 μm.

[0017] Figure 7 This is the result of the effect of phytic acid on the pathogenicity of *Helicobacter pylori* in Example 4 of the present invention; wherein, Figure 7 (a) Disease incidence on leaves of rice ZH11 after inoculation with *Helicobacter oryzae*, scale bar = 1 cm. Figure 7 (b) Statistics on the lesion area of ​​rice ZH11 leaves after inoculation with Helicobacter pylori.

[0018] Figure 8 This is the verification result of phytic acid-induced resistance to rice pyrenoidosa in Example 5 of the invention. Detailed Implementation

[0019] The present invention will be further described in detail below with reference to specific embodiments and accompanying drawings, but the scope of protection of the present invention is not limited to the content described therein; unless otherwise specified, all reagents used in the present invention are commercially available analytical grade reagents, and all raw materials used in the present invention can be purchased through conventional commercial channels.

[0020] Rice hygroscopic spirilla ( Bipolaris oryzae As the main pathogen causing rice leaf spot disease, this invention uses exogenous *Helicobacter pylori* to infect rice with rice leaf spot disease. Those skilled in the art can purchase *Helicobacter pylori* from commercial sources as needed.

[0021] The culture medium and its preparation method used in this invention: CM II medium: (1) Weigh 25 mL of 20× nitrate solution, 0.5 mL of 1000× trace element solution, 5 g of glucose, 1 g of peptone, 0.5 g of yeast extract, 0.5 g of acid-hydrolyzed casein, 0.5 mL of 1000× vitamin solution, and 7.5 g of agar powder; stir until fully dissolved and then add distilled water to make up to 500 mL.

[0022] (2) Sterilize with high-pressure steam at 121℃ for 20 min.

[0023] (3) In a clean bench, pour the culture medium into a 6 cm culture dish.

[0024] Rice bran culture medium: Weigh 7 g of rice flour, 1.25 g of yeast extract, 10 g of rice bran, and 10 g of agar, add them to 500 mL of distilled water and stir thoroughly to dissolve; autoclave at 121℃ for 20 min; pour the culture medium into a 6 cm petri dish in a clean bench.

[0025] Liquid SYM medium: Weigh 1.5 g of sucrose, 5 g of soluble starch, and 1 g of yeast extract, add them to 500 mL of distilled water and stir thoroughly to dissolve; autoclave at 121℃ for 20 min.

[0026] Example 1 (1) Preparation of *Hymenochrysis oryzae* conidia suspension: *Hymenochrysis oryzae* was inoculated into CM II medium and activated under 28℃ and 12h light. It was then inoculated onto rice bran medium (using *Hymenochrysis oryzae* blocks with a diameter of 5 mm as the initial inoculum) and cultured at 25℃ and 12h light for 7-10 days. The *Hymenochrysis oryzae* conidia suspension was collected using a 0.02% Tween solution, and the concentration of the *Hymenochrysis oryzae* conidia suspension was adjusted to 1.5 × 10⁻⁶. 5 1 conidia / mL.

[0027] (2) Take the conidial suspension of *Hymenopterus indica* obtained in step (1) and spray it on three-week-old rice seedlings of variety Zhonghua 11 (ZH11). At the same time, select three-week-old ZH11 seedlings with the same growth status and spray them with an equal volume concentration of 0.02% Tween solution as a control. After 48 h, collect the leaves of ZH11 seedlings inoculated with *Hymenopterus indica* and control ZH11 seedlings.

[0028] (3) After the leaves collected in step (2) are thoroughly ground under liquid nitrogen, 0.20 g of the sample is accurately weighed into a 2 mL centrifuge tube; then 1 mL of 8 mol / L urea aqueous solution is added, mixed well and extracted by ultrasonication at 4℃ for 30 min; after the extraction, the sample is centrifuged at 12000 r / min for 20 min at 4℃; 0.2 mL of supernatant is taken, 0.8 mL of methanol is added, mixed well and then 0.12 mL of trimethylsilazomethane (CAS: 18107-18-1) is added, and the reaction is carried out at 25℃ for 60 min. After the reaction is completed, 50 μL of formic acid is added to terminate the reaction and the derivatized product solution is obtained. After nitrogen blowing, it is reconstituted with 0.2 mL of water; after passing through a 0.45 μm filter membrane, it is diluted 5 times to obtain the UPLC-MS / MS detection sample.

[0029] (4) The phytic acid content in the sample obtained in step (3) was detected by Chongqing Bonuoheng Biotechnology Co., Ltd. using UPLC-MS / MS. The results are as follows: Figure 1 As shown, compared with the control, the phytic acid content in ZH11 seedlings was significantly increased 48 h after inoculation with *Helicobacter pylori*; "**" indicates extremely significant difference (**). P <0.01, Student's t The test indicates that phytic acid, as a key defense metabolite in rice, actively participates in the rice's defense response to Helicobacter pylori infection.

[0030] Example 2 OsITPK6 The gene encoding inositol 1,3,4-triphosphate 5 / 6-kinase 6 has been found to play an important role in phytate biosynthesis in rice; this example further investigates the genes related to phytate biosynthesis after infection with ZH11 by *Helicobacter pylori*. OsITPK6 The transcriptional level, specifically the following steps: (1) Take the rice hygroscopic conidia suspension obtained in step (1) of Example 1 and spray it on ZH11 seedlings that have been cultured for three weeks. Use ZH11 seedlings that have not been inoculated with rice hygroscopic conidia as a control. Collect the leaves of the inoculated and control ZH11 seedlings after 24 h and 48 h of treatment, respectively, extract RNA and reverse transcribe it into cDNA.

[0031] (2) Detection using RT-qPCR OsITPK6 The transcription level was determined using the forward primer shown in SEQ ID NO: 1 and the reverse primer shown in SEQ ID NO: 2. OsUBQ The gene (Gene Report: LOC_Os03g13170) is an internal reference gene; the RT-qPCR system is shown in Table 1: Table 1 RT-qPCR system The RT-qPCR program is shown in Table 2: Table 2 RT-qPCR program (3) RT-qPCR results are as follows Figure 2 As shown, at 24 h and 48 h after treatment, compared with the control, the ZH11 seedlings inoculated with *Helicobacter pylori* showed significantly higher growth rates. OsITPK6 The transcriptional level was significantly upregulated, indicating that *Helicobacter pylori* induced morphogenesis in rice. OsITPK6 Gene expression; Figure 2 The "**" in the text represents a highly significant difference (**). P <0.01, Student's t -test).

[0032] Example 3 verify OsITPK6 The following steps were taken to investigate the changes in phytic acid content in rice and its resistance to sesame leaf spot disease after the knockout process: (1) We commissioned Weimi Biotechnology Co., Ltd. to knock out the strain in the genetic background of rice variety ZH11. OsITPK6 Genes acquire two homozygous mutations of different types. OsITPK6 Knockout mutants, respectively Ositpk6-1 and Ositpk6-2 ,in Ositpk6-1 An 11-base deletion occurred in the nucleotides at positions 193 to 203 of the coding region; Ositpk6-2 A single base deletion occurred at nucleotide position 199 in the coding region, resulting in a frameshift mutation.

[0033] (2) The suspension of *Helicobacter pylori* conidia obtained in step (1) of Example 1 was separately subjected to... Ositpk6-1 , Ositpk6-2 Spray inoculation was performed on wild-type ZH11 rice. The inoculated rice was then cultured at 28℃, 12 h light, and 70% relative humidity. The incidence of sesame leaf spot disease on ZH11 leaves was observed 48 h post-inoculation. The results are as follows: Figure 3 As shown in (a), compared to the wild type, Ositpk6-1 and Ositpk6-2 Susceptibility to sesame leaf spot disease increased significantly, and the area of ​​lesions on the leaves was statistically analyzed, with the results as follows: Figure 3 As shown in (b), Ositpk6-1 and Ositpk6-2 The lesion area was significantly increased compared to wild-type ZH11, indicating that... OsITPK6 Gene deletion increases susceptibility of rice to sesame leaf spot disease; "**" indicates highly significant difference (**). P <0.01, Student'st -test).

[0034] (3) Collection Ositpk6-1 , Ositpk6-2 Leaves of wild-type ZH11 were thoroughly ground under liquid nitrogen, and 0.20 g of the sample was accurately weighed into a 2 mL centrifuge tube. Then, 1 mL of 8 mol / L urea aqueous solution was added, mixed well, and extracted by ultrasonication at 4℃ for 30 min. After extraction, the sample was centrifuged at 12000 r / min for 20 min at 4℃. 0.2 mL of the supernatant was taken, 0.8 mL of methanol was added, mixed well, and 0.12 mL of trimethylsilazomethane (CAS: 18107-18-1) was added. The mixture was reacted at 25℃ for 60 min. After extraction, 50 μL of formic acid was added to terminate the reaction, and the derivatized product solution was obtained. After nitrogen blowing, the solution was reconstituted with 0.2 mL of water. The solution was filtered through a 0.45 μm filter membrane and then diluted 5 times to obtain the sample for UPLC-MS / MS detection.

[0035] (4) The phytic acid content in each group of rice was detected by Chongqing Bonuoheng Biotechnology Co., Ltd. using UPLC-MS / MS. The results are as follows: Figure 3 As shown in (c), homozygous OsITPK6 Knockout mutant Ositpk6-1 and Ositpk6-2 Phytic acid levels were significantly lower in the medium-sized ZH11 compared to the wild-type ZH11, with "**" indicating a highly significant difference (**). P <0.01, Student's t -test), further proof OsITPK6 It plays an important role in the biosynthesis of phytic acid in rice.

[0036] Example 4 The specific steps for verifying the in vitro antibacterial activity of phytic acid are as follows: (1) The effect of phytic acid on the vegetative growth of rice hygroscopic worms, the specific steps of which are as follows: ① In step (3) of preparing CMII agar medium, phytic acid solutions with final concentrations of 0.5 mg / mL (pH=4.54), 1 mg / mL (pH=4.02), 1.5 mg / mL (pH=3.85) and 2 mg / mL (pH=3.74) were added to form the phytic acid group; the CMII agar medium was adjusted to the same pH value as the phytic acid group with hydrochloric acid (HCl) to form the hydrochloric acid group; and water was used as the control group (Mock).

[0037] ② Take the activated *Helicobacter pylori* obtained in step (1) of Example 1, and take *Helicobacter pylori* blocks with a diameter of 5 mm as initial inoculum. Inoculate them onto the CMII agar medium prepared in step ① with pH=4.54 (0.5 mg / mL), pH=4.02 (1 mg / mL), pH=3.85 (1.5 mg / mL), pH=3.74 (2 mg / mL), pH=4.54 (4.02), pH=3.85 (3.74), pH=3.74 (2 mg / mL), pH=4.54 (4.02), pH=3.85 (3.74), and pH=3.74 (control group). Incubate at 28°C for 48 h, and photograph and record the growth of *Helicobacter pylori* colonies. The results are as follows: Figure 4 As shown in (a), under the same pH conditions, phytic acid significantly inhibited the growth of *Hymenochloa oryzae* hyphae compared to hydrochloric acid; the colony diameter (D) of *Hymenochloa oryzae* was also measured. The inhibition rates of phytic acid and hydrochloric acid treatments on the growth of *Hymenochloa oryzae* hyphae were calculated using the following formula: (Equation 4-1) In Equation 4-1, D1 is the diameter of *Rhizopus oryzae* colonies in the control group, and D0 is the diameter of *Rhizopus oryzae* colonies in the phytic acid group or the hydrochloric acid group.

[0038] Its growth inhibition results are as follows Figure 4 As shown in (b), in summary, when phytic acid was added to agar medium at final concentrations of 0.5 mg / mL, 1 mg / mL, 1.5 mg / mL, and 2 mg / mL, the vegetative growth of *Helicobacter pylori* was significantly inhibited compared with the hydrochloric acid group and the control group; and the growth inhibition rate of *Helicobacter pylori* increased significantly with the increase of phytic acid concentration. Figure 4 In the text, "*" indicates a significant difference, and "**" indicates an extremely significant difference (*). P <0.1,** P <0.01, Student's t -test).

[0039] (2) The effect of phytic acid on the germination of rice pyrenoidosa spores, the specific steps of which are as follows: ① Take the *Hymenochrysis oryzae* conidia suspension prepared in step (1) of Example 1, add phytic acid to make the final concentrations of phytic acid in the *Hymenochrysis oryzae* conidia suspension 0.5 mg / mL (pH=4.54), 1 mg / mL (pH=4.02), 1.5 mg / mL (pH=3.85), and 2 mg / mL (pH=3.74), respectively, as the phytic acid group; adjust the *Hymenochrysis oryzae* conidia suspension to the same pH value as the phytic acid group with hydrochloric acid, as the hydrochloric acid group; add water as the control group (Mock); take the *Hymenochrysis oryzae* conidia suspensions from the phytic acid group, hydrochloric acid group, and control group respectively and drop them onto the surface of a hydrophobic glass slide. After culturing for 1 h under 28°C, high humidity, and dark conditions, observe the spore germination under a microscope. The results are as follows. Figure 5 As shown in (a), spore germination was inhibited in the phytic acid group under the same pH conditions. The germination rate was calculated by counting the number of germinated spores in each of the three groups (50 conidia per group), using the following formula: (Equation 5-1) The spore germination rate results for each group are as follows: Figure 5 As shown in (b), compared with the hydrochloric acid group and the control group, phytic acid treatment significantly inhibited the germination of conidia of *Hymenochrysis oryzae*, and the germination rate of *Hymenochrysis oryzae* conidia decreased significantly with increasing phytic acid concentration. Figure 5 The "**" in the text represents a highly significant difference (**). P <0.01, Student's t -test).

[0040] (3) The effect of phytic acid on the hyphal morphology of rice pyrenoidosa is as follows: *Hydrilla verticillata* was inoculated into CM II medium and activated under 28℃ and 12h light. The inoculum was then transferred to CM II medium (using 5 mm diameter *Hydrilla verticillata* blocks as initial inoculum) and cultured at 25℃ and 12h light for 4-5 days. The conidial suspension of *Hydrilla verticillata* was collected using purified water, and the concentration of the conidial suspension was adjusted to 1.5 × 10⁻⁶. 5 1 conidia / mL.

[0041] The above-mentioned 2 mL suspension of *Hymenochrysis oryzae* conidia was inoculated into 5 mL of liquid SYM medium, and phytic acid was added to a final concentration of 1 mg / mL, serving as the phytic acid group; the liquid SYM medium was adjusted to the same pH value as the phytic acid group with hydrochloric acid, serving as the hydrochloric acid group; water was added as the control group; each system was cultured in a shaker at 28°C and 80 rpm, and after 3 h and 4 h of culture, the culture solution was aspirated onto glass slides, and the hyphal morphology was observed under a microscope. The results are as follows: Figure 6As shown, after phytic acid treatment, the mycelial cells of *Hymenochrysis oryzae* conidia germinating exhibited depolarization growth and mycelial cell rupture; however, this phenomenon was not observed in the hydrochloric acid group and the control group. These results indicate that phytic acid directly inhibits the growth of *Hymenochrysis oryzae* by inducing mycelial cell depolarization.

[0042] (4) The effect of phytic acid on the pathogenicity of rice molluscum contagiosum, the specific steps of which are as follows: Take the rice spore suspension obtained in step (1) of Example 1, add phytic acid to a final concentration of 1 mg / mL, and use it as the phytic acid group; adjust the spore suspension to the same pH value as the phytic acid group with hydrochloric acid, and use it as the hydrochloric acid group; add an equal amount of water to the spore suspension as the control group; spray three-week-old ZH11 rice seedlings with the three groups of spore suspensions respectively, and after treatment, infect the ZH11 rice seedlings in the dark and sealed environment for 24 h, and continue to cultivate under light for 24 h, and observe the disease situation. The results are as follows. Figure 7 As shown in (a), the phytic acid group had fewer lesions, and compared with the control treatment, phytic acid could effectively reduce the pathogenicity of rice blastiae and reduce the affected area in rice. Figure 7 (b) indicates that 1 mg / mL phytic acid has a good control effect on the occurrence of rice leaf spot disease. Figure 7 The "**" in the text represents a highly significant difference (**). P <0.01, Student's t -test).

[0043] Example 5 The specific steps for verifying phytic acid-induced resistance to rice helicobacter pylori are as follows: (1) Select three-week-old ZH11 rice seedlings with the same growth status and randomly divide them into three groups. One group was sprayed with phytic acid with a final concentration of 1 mg / mL as the phytic acid group; another group was sprayed with hydrochloric acid with the same pH value; and the last group was sprayed with water as the control group. After treatment, the seedlings were cultured at 28℃, light for 12 h and relative humidity of 70%.

[0044] (2) Leaf samples were collected from three groups after 24 h and 48 h of treatment, respectively. RNA was extracted and reverse transcribed into cDNA. Resistance-related genes were detected by RT-qPCR. OsPR1a , OsPR5 , OsPR10a The expression, in OsUBQ (Gene Report: LOC_Os03g13170) was used as an internal reference gene; among which, detection... OsPR1a , OsPR5 and OsPR10a The primers are shown in Table 3: Table 3. RT-qPCR primer sequences for resistance-related genes The RT-qPCR system for detecting resistance-related genes is shown in Table 1 of Example 1, and the RT-qPCR procedure is shown in Table 2 of Example 1.

[0045] OsPR1a , OsPR5 and OsPR10a These are genes encoding important disease-associated proteins (PR proteins) in rice, belonging to the PR-1, PR-5, and PR-10 families, and are often used as molecular markers for the activation of rice defense responses; RT-qPCR results are as follows... Figure 8 As shown, after 24 h and 48 h of phytic acid treatment, the expression levels of these three resistance-related genes were significantly upregulated compared with the hydrochloric acid group and the control group, indicating that phytic acid treatment can induce disease resistance in rice. Figure 8 The "**" in the text represents a highly significant difference (**). P <0.01, Student's t -test).

[0046] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. The application of a phytic acid in the resistance of rice to sesame leaf spot disease, characterized in that, The specific steps involve spraying phytic acid onto the surface of rice leaves.

2. The application of the phytic acid according to claim 1 in the resistance of rice to sesame leaf spot disease, characterized in that, The structural formula of the phytic acid is shown in Formula I: Formula I.

3. The application of phytic acid in rice resistance to sesame leaf spot disease according to claim 1, characterized in that, The concentration of phytic acid is 0.5-2 mg / mL.

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