Application and methods of low-temperature resistance in oilseed and vegetable crops.
By using iron dihydroporphyrin as a cryoprotectant on crops such as rapeseed and chili peppers, the problem of freezing damage to oilseed and vegetable crops at low temperatures has been solved, enhancing their resistance to low temperatures and reducing the risk of yield reduction.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- JIANGSU ACAD OF AGRI SCI
- Filing Date
- 2024-04-26
- Publication Date
- 2026-05-26
AI Technical Summary
In existing technologies, oilseed and vegetable crops such as rapeseed and chili peppers are susceptible to frost damage under low-temperature conditions, leading to reduced yields. Furthermore, the application of dihydroporphyrin iron is mainly limited to regulating plant growth and development, without involving research on low-temperature protective agents.
Dihydroporphyrin iron was used as a low-temperature protectant for oilseed and vegetable crops. It was prepared as a 0.01wt% to 0.03wt% soluble powder or a 0.1μg/mL to 0.3μg/mL solution by foliar spraying. The treatment was carried out within 24 to 48 hours before the low temperature was reached, which enhanced the activity of antioxidant enzymes and the accumulation of osmotic regulators in plants.
It effectively reduces the chilling injury index, alleviates cell membrane damage, enhances cold resistance, increases antioxidant enzyme activity, improves the low-temperature resistance of oilseed and vegetable crops, reduces the chilling injury index, and provides stress resistance.
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Figure CN118355918B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of agricultural growth regulators, and in particular to the application of dihydroporphyrin iron in low-temperature resistance of oilseed and vegetable crops, and methods for achieving low-temperature resistance. Background Technology
[0002] Due to global warming, extreme weather events are becoming more frequent in winter and spring, with cold damage and freezing damage showing a trend of frequent and severe occurrences. Moreover, their abnormality and unpredictability are increasing. Therefore, it is proposed to strengthen the construction of disaster prevention system and agricultural production disaster prevention and relief guarantee, and to enhance the construction of agricultural disaster prevention and mitigation capabilities.
[0003] Rapeseed is the most important oilseed crop, the primary source of edible vegetable oil, and a potential major source of feed protein, second only to soybean meal. In production, winter frost damage is the main hazard for rapeseed. Rapeseed suffers frost damage when temperatures drop to -3 to -5℃, with more severe damage at -7 to -8℃. Winter-hardy varieties can withstand temperatures below -10℃. Low temperatures and strong winds in winter exacerbate frost damage to rapeseed. Frost damage during the seedling stage easily leads to plant injury or death; frozen stems become hollow, crack, and the tips wither and droop, eventually dying; frost damage during the budding and flowering stages causes flower buds to turn yellow, shrink, and fail to produce seeds; the bolting and flowering stages are also sensitive to low temperatures. Frost damage at different stages causes varying degrees of yield reduction, generally 10-30%, and in severe cases, more than 50%, posing an increasingly significant challenge to rapeseed production.
[0004] Chili peppers (Capsicum annuum L.) are rich in nutrients and have a unique spicy flavor, making them popular with consumers. Besides being eaten fresh, they can also be used as a condiment and processed to extract capsaicin and paprika oleoresin. As a globally popular vegetable crop, the global planting area and yield of chili peppers are increasing year by year. Chili peppers prefer warm temperatures and are susceptible to frost damage. They are annual or deciduous perennial plants, with an optimal temperature range of 15-34℃. Below 15℃, chili peppers grow very slowly and cannot set fruit; below 10℃, growth ceases; and below 5℃, the plants suffer varying degrees of frost damage, leading to plant death and ultimately reduced yield. Therefore, improving the stress resistance and frost resistance of chili peppers has significant practical importance and application value.
[0005] Iron chlorine e6 (CAS No.: 15492-44-1) is a novel plant immune inducer jointly developed by Nanjing Baxter Biotechnology Co., Ltd. and Jiangsu Academy of Agricultural Sciences. The technical grade of this product is a dark green, loose, powdery solid with characteristics such as inhibiting chlorophyllase, delaying chlorophyll degradation to enhance photosynthesis, promoting root growth, increasing germination rate, and increasing stress resistance. Numerous experiments have shown that iron chlorine not only promotes plant growth but also enhances crop stress resistance. For example, it promotes the growth of rice and tobacco and improves the frost resistance of rapeseed during the overwintering period. Iron chlorine can also promote wheat growth, enhance fertilizer absorption, reduce fertilizer usage, has no adverse effects on crop quality, and is not prone to accumulation or residue, resulting in significant yield and income increases.
[0006] Currently, the application of dihydroporphyrin iron is limited to regulating plant growth and development, and its potential use as a plant low-temperature protectant has not yet been studied. Summary of the Invention
[0007] The purpose of this invention is to address the shortcomings of existing technologies by providing the application of dihydroporphyrin iron in low-temperature resistance of oilseed and vegetable crops, as well as methods for low-temperature resistance, so as to improve the stress resistance and frost resistance of oilseed and vegetable crops.
[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:
[0009] Firstly, a low-temperature protective agent for oilseed and vegetable crops is provided, comprising:
[0010] Dihydroporphyrin iron.
[0011] In some of these embodiments, the dihydroporphyrin iron is a solution prepared from a soluble powder with a concentration of 0.01 wt% to 0.03 wt%.
[0012] In some of these embodiments, the dihydroporphyrin iron is a dihydroporphyrin iron solution diluted 500 to 10000 times based on a solution of a soluble powder with a concentration of 0.01 wt% to 0.03 wt%.
[0013] Preferably, in some embodiments, the dihydroporphyrin iron is a dihydroporphyrin iron solution diluted 1000 times based on a solution of a soluble powder with a concentration of 0.02 wt%.
[0014] In some of these embodiments, the dihydroporphyrin iron is a dihydroporphyrin iron solution with a concentration of 0.1 μg / mL to 0.3 μg / mL.
[0015] Preferably, in some embodiments, the dihydroporphyrin iron is a dihydroporphyrin iron solution with a concentration of 0.2 μg / mL.
[0016] In a second aspect, a method for protecting oilseed and vegetable crops against low temperatures using iron dihydroporphyrin or the low-temperature protectant for oilseed and vegetable crops as described in the first aspect is provided, comprising:
[0017] Using iron dihydroporphyrin to treat oilseeds and vegetable crops.
[0018] In some of these embodiments, the leaves of oilseed and vegetable crops are sprayed with iron dihydroporphyrin 24 to 48 hours before the crops are exposed to low temperatures.
[0019] In some of these embodiments, a dihydroporphyrin iron solution diluted 500 to 10000 times with a soluble powder solution at a concentration of 0.01 wt% to 0.03 wt% is sprayed onto the leaves of oilseed and vegetable crops.
[0020] In some of these embodiments, a dihydroporphyrin iron solution diluted 1000 times with a soluble powder solution at a concentration of 0.02 wt% is sprayed onto the leaves of oilseed and vegetable crops.
[0021] In some of these embodiments, a solution of iron dihydroporphyrin at a concentration of 0.1 μg / mL to 0.3 μg / mL was sprayed onto the leaves of oilseed and vegetable crops.
[0022] In some of these embodiments, a 0.2 μg / mL solution of dihydroporphyrin iron was sprayed onto the leaves of oilseed and vegetable crops.
[0023] Thirdly, this invention provides an application of iron dihydroporphyrin or a cryoprotectant for oilseed and vegetable crops as described in the first aspect in the application of cryoprotection in oilseed and vegetable crops.
[0024] The application of dihydroporphyrin iron in low-temperature resistance of oilseeds and vegetable crops, and the method for low-temperature resistance, of the present invention have at least the following beneficial effects:
[0025] 1) Treating oilseed and vegetable seedlings under low temperature stress with the plant low temperature resistance regulator containing dihydroporphyrin iron of the present invention can effectively reduce the chilling injury index, alleviate plasma membrane damage, increase the accumulation of osmotic regulators, enhance cold resistance, and improve antioxidant enzyme activity, thereby protecting the reactive oxygen metabolism system of oilseed and vegetable crops from damage and improving the low temperature resistance of oilseed and vegetable seedlings.
[0026] 2) The plant low-temperature resistance regulator containing dihydroporphyrin iron of the present invention has a certain stress resistance effect on oil crops and vegetable crops, and can reduce the chilling injury index of oil crops and vegetable crops, providing a new idea and reference for improving the low-temperature resistance of oil crops and vegetable crops. Attached Figure Description
[0027] Figure 1 The effect of iron dihydroporphyrin regulator on pepper seedlings under low temperature stress;
[0028] Figure 2 The effect of iron dihydroporphyrin regulator on malondialdehyde (MDA) content in pepper seedlings under low temperature stress;
[0029] Figure 3a The effect of dihydroporphyrin iron regulator on the soluble sugar content of pepper leaves in pepper seedlings under low temperature stress;
[0030] Figure 3b The effect of dihydroporphyrin iron regulator on proline content in pepper seedlings under low temperature stress;
[0031] Figure 4 The effect of dihydroporphyrin iron regulator on the content of reduced glutathione (GSH) in pepper seedlings under low temperature stress;
[0032] Figure 5a The effect of iron dihydroporphyrin regulator on superoxide dismutase (SOD) activity in pepper leaves under low temperature stress;
[0033] Figure 5b The effect of iron dihydroporphyrin regulator on the activity of physical peroxidase (POD) in pepper leaves under low temperature stress;
[0034] Figure 6 The effect of iron dihydroporphyrin regulator on rapeseed seedlings under low temperature stress;
[0035] Figure 7a The effect of dihydroporphyrin iron regulator on the overwintering state of rapeseed under low temperature stress;
[0036] Figure 7b The effect of iron dihydroporphyrin regulator on the bolting stage of rapeseed under low temperature stress;
[0037] Figure 7c The effect of iron dihydroporphyrin regulator on the number of branches in rapeseed under low temperature stress;
[0038] Figure 7d The effect of iron dihydroporphyrin regulator on the number of pods in rapeseed under low temperature stress;
[0039] In the figure, the data are the mean ± standard error, and different letters indicate that the differences between different treatments are statistically significant (P<0.05) as tested by the SigmaPlot method. Detailed Implementation
[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0041] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.
[0042] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.
[0043] Example 1
[0044] This embodiment relates to the low-temperature protection agent for oilseed and vegetable crops of the present invention.
[0045] A low-temperature protectant for oilseed and vegetable crops, comprising iron dihydroporphyrin.
[0046] Oilseed and vegetable crops include, but are not limited to, rapeseed, chili peppers, and tomatoes.
[0047] In some of these embodiments, the dihydroporphyrin iron is a solution prepared from a soluble powder with a concentration of 0.01 wt% to 0.03 wt%.
[0048] Preferably, the dihydroporphyrin iron is a dihydroporphyrin iron solution diluted 500 to 10000 times based on a solution of soluble powder with a concentration of 0.01 wt% to 0.03 wt%.
[0049] More preferably, the dihydroporphyrin iron is a dihydroporphyrin iron solution diluted 1000 times based on a solution of a soluble powder with a concentration of 0.02 wt%.
[0050] In some of these embodiments, the dihydroporphyrin iron is a dihydroporphyrin iron solution with a concentration of 0.1 μg / mL to 0.3 μg / mL.
[0051] Preferably, the dihydroporphyrin iron is a dihydroporphyrin iron solution with a concentration of 0.2 μg / mL.
[0052] The application of the dihydroporphyrin iron of the present invention in the low-temperature resistance of oilseed and vegetable crops has at least the following beneficial effects:
[0053] 1) Treating oilseed and vegetable seedlings under low temperature stress with the plant low temperature resistance regulator containing dihydroporphyrin iron of the present invention can effectively reduce the chilling injury index, alleviate plasma membrane damage, increase the accumulation of osmotic regulators, enhance cold resistance, and improve antioxidant enzyme activity, thereby protecting the reactive oxygen metabolism system of oilseed and vegetable crops from damage and improving the low temperature resistance of oilseed and vegetable seedlings.
[0054] 2) The plant low-temperature resistance regulator containing dihydroporphyrin iron of the present invention has a certain stress resistance effect on oil crops and vegetable crops, and can reduce the chilling injury index of oil crops and vegetable crops, providing a new idea and reference for improving the low-temperature resistance of oil crops and vegetable crops.
[0055] Example 2
[0056] This embodiment relates to the low-temperature resistance method for oilseed and vegetable crops of the present invention.
[0057] A method for protecting oil crops and vegetable crops against low temperatures using iron dihydroporphyrin or a low-temperature protectant for oil crops and vegetable crops as described in Example 1, comprising: treating oil crops and vegetable crops with iron dihydroporphyrin.
[0058] Oilseed and vegetable crops include, but are not limited to, rapeseed, chili peppers, and tomatoes.
[0059] Spray the leaves of oilseed and vegetable crops with dihydroporphyrin iron 24 to 48 hours before they experience low temperatures.
[0060] Preferably, the leaves of oilseed and vegetable crops are sprayed once with dihydroporphyrin iron within 24 to 48 hours before the oilseed and vegetable crops are exposed to low temperatures.
[0061] Preferably, the leaves of oilseed and vegetable crops are sprayed multiple times with dihydroporphyrin iron within 24 to 48 hours before the crops experience low temperatures. The interval between the multiple sprays is 5 to 7 days.
[0062] Preferably, within 24 hours before the oilseed and vegetable crops are subjected to low temperatures, a dihydroporphyrin iron solution diluted 500 to 10000 times with a soluble powder solution of 0.01 wt% to 0.03 wt% is sprayed onto the leaves of the oilseed and vegetable crops.
[0063] More preferably, a dihydroporphyrin iron solution diluted 1000 times with a solution of soluble powder with a concentration of 0.02 wt% is sprayed onto the leaves of oilseed and vegetable crops.
[0064] Preferably, within 24 hours before the oilseed and vegetable crops are subjected to low temperature, the leaves of the oilseed and vegetable crops are sprayed with a dihydroporphyrin iron solution with a concentration of 0.1 μg / mL to 0.3 μg / mL.
[0065] More preferably, within 24 hours before the oilseed and vegetable crops are subjected to low temperature, the leaves of the oilseed and vegetable crops are sprayed with a 0.2 μg / mL dihydroporphyrin iron solution.
[0066] Example 3
[0067] This embodiment relates to the application of dihydroporphyrin iron or the low-temperature protection agent for oilseeds and vegetable crops as described in Example 1 in the low-temperature resistance of chili peppers.
[0068] The tested chili pepper variety was the low-temperature sensitive chili pepper variety "Sujiao No. 5".
[0069] The seeds of the tested chili peppers were soaked in a 10%–15% NaClO solution for 10 minutes, then rinsed with clean water until odorless, and soaked in water at 25℃ for 24 hours. The seeds were then sown in 72-cell seedling trays filled with nutrient substrate. The nutrient substrate was prepared at a volume ratio of seedling substrate to vermiculite of 5:2. The chili pepper seedlings were grown under conditions of 25 / 17℃ and a 12h / 12h (day / night) photoperiod. The seedlings were irrigated three times a week, twice with tap water and once with a water-soluble fertilizer.
[0070] When the tenth true leaf of the pepper seedlings began to develop (45-50 days after planting), pepper seedlings with similar growth were selected and divided into experimental and control groups. The experimental group was sprayed with 0.2 μg / mL of dihydroporphyrin iron spray, while the control group was sprayed with water until the leaf surface was evenly covered with droplets. After spraying, the experimental and control groups were kept out of the light for 24 hours.
[0071] Twenty-four hours later, the experimental and control groups were placed in an artificial climate chamber for 4°C low-temperature stress treatment. At different time points after the low-temperature stress treatment (0h, 6h, 12h, 24h), leaves were collected from nine pots of peppers in each of the experimental and control groups. The collected leaves were immediately frozen in liquid nitrogen and stored at -80°C.
[0072] (I) Determination of Chill Injury Index in Chili Seedlings
[0073] Plant cold tolerance is classified into five levels: 0, 1, 2, 3, and 4. The grading criteria are as follows:
[0074] Grade 0: The plant shows no obvious symptoms of cold damage;
[0075] Grade 1: The lower leaves of the plant show slight water loss at the leaf margins, but there are no other obvious symptoms of cold damage;
[0076] Grade 2: The lower leaves of the plant have severe water loss at the leaf margins, while the upper leaves have slight water loss at the leaf margins;
[0077] Level 3: Dehydration spots appear on the leaf margins of the lower leaves of the plant, the leaf margins of the upper leaves are severely dehydrated, and there are no obvious symptoms of cold damage in the heart leaves;
[0078] Level 4: Dehydration spots on the lower leaves of the plant merge into a single patch, the leaves wilt, dehydration spots appear on the upper leaves, and the heart leaves lose some water.
[0079] The statistical method for the chilling injury index of pepper seedlings is as follows: Chilling injury index = (number of diseased plants at each level × level) / (total number of plants × highest level).
[0080] Results of chilling injury index measurement for pepper seedlings:
[0081] from Figure 1 The results showed that after 48 hours of low-temperature stress treatment, the leaves of the control group plants exhibited severe wilting, while only a few leaf tips of the experimental group plants showed slight wilting, and most leaves were fully expanded.
[0082] As shown in Table 1, after 24 hours of low-temperature stress treatment, the chilling injury index of the experimental group was less than 30%, while that of the control group was greater than 40%. After 48 hours of low-temperature stress treatment, the chilling injury index of the experimental group was 41.75%, while that of the control group was 52%. After 72 hours of low-temperature stress treatment, the chilling injury index of the experimental group was 52.16%, while that of the control group reached 73.83%. This indicates that dihydroporphyrin iron spray can effectively reduce the chilling injury index of pepper seedlings under low-temperature stress.
[0083]
[0084] Table 1 Chilling injury index of pepper seedlings under low temperature with different types of dihydroporphyrin iron solution
[0085] (II) Determination of biofilm damage indicators
[0086] When plants are subjected to low-temperature damage, the plasma membrane, as the initial site of injury, undergoes a phase transition in cell membrane permeability. Therefore, the extent of electrolyte leakage from plant cells can reflect the degree of damage suffered by the plant during low-temperature stress, and the content of malondialdehyde (MDA) is considered an important indicator for measuring membrane damage.
[0087] Method for determining malondialdehyde (MDA) content: determined by the reaction with 2-thiobarbituric acid (TBA).
[0088] Results of malondialdehyde (MDA) content determination:
[0089] from Figure 2 It can be seen that, compared with normal temperature (0h), low temperature stress increased the malondialdehyde (MDA) content of peppers. After 6h of low temperature stress, the MDA content of the experimental group was 20.46% lower than that of the control group. After 12h of low temperature stress, the MDA content of the experimental group was significantly lower than that of the control group by 30.33%. After 24h of low temperature stress, the MDA content of the experimental group was 54.21% lower than that of the control group. All the above comparison data reached the significance level (p<0.05), indicating that dihydroporphyrin iron spray can effectively alleviate the plasma membrane damage of pepper seedlings under low temperature stress.
[0090] (III) Determination of osmotic conditioning substances
[0091] The determination of soluble sugars (SS) and proline (Pro) was performed according to the method described by Li et al. (2015).
[0092] Results of soluble sugar (SS) and proline (Pro) determination:
[0093] like Figure 3a As shown, overall, at room temperature (0h), the soluble sugar (SS) content of chili pepper leaves increased by 35.07% compared with the control group; after 12h of low temperature stress, the soluble sugar (SS) content of chili pepper leaves in the experimental group increased significantly by 411.22% compared with the control group; after 24h of low temperature stress, the soluble sugar (SS) content of chili pepper leaves in the experimental group increased by 76.75% compared with the control group; after 6h of low temperature stress, there was no significant difference in the soluble sugar (SS) content of chili pepper leaves between the experimental group and the control group, indicating that dihydroporphyrin iron spray can significantly increase the soluble sugar (SS) content of chili pepper leaves with the extension of low temperature stress time.
[0094] like Figure 3bAs shown, the proline (Pro) content in the pepper leaves of the experimental group showed a trend of first increasing and then decreasing, but it was significantly higher than that in the control group. At room temperature (0 h), the proline (Pro) content in the pepper leaves of the experimental group increased by 41.9% compared with the control group. After 6 h of low temperature stress, the proline (Pro) content in the pepper leaves of the experimental group increased by 32.73% compared with the control group. After 12 h of low temperature stress, the proline (Pro) content in the pepper leaves of the experimental group increased by 40.88% compared with the control group. After 24 h of low temperature stress, the proline (Pro) content in the pepper leaves of the experimental group increased by 35.91% compared with the control group. The differences between the experimental group and the control group at 6 h and 12 h of low temperature stress were statistically significant (p<0.05), indicating that the dihydroporphyrin iron spray further increased the accumulation of osmotic regulators in pepper leaves under low temperature stress.
[0095] (iv) Determination of reduced glutathione (GSH) content
[0096] The determination of reduced glutathione and oxidized glutathione content was based on a slight modification of the Griffith (1980) method. Extraction was performed with 5% sulfosalicylic acid, followed by centrifugation at 12,000g for 20 min at 4°C.
[0097] The reaction system for determining total glutathione content consisted of: 200 μL of 0.5 M phosphate buffer (6.3 mM EDTA, pH 7.5), 560 μL of 10 mM EDTA, 100 μL of 6 mM 5,5'-dithiobis(2-nitrobenzoic acid)DTNB, 100 μL of 2.1 mM NADPH, and 20 μL of supernatant. The reaction was started with 1 U GR, and the absorbance was measured at 412 nm.
[0098] Determination of oxidized glutathione (GSSG): Add 200 μL of phosphate buffer and 4 μL of 2-vinylpyridine to 20 μL of supernatant, incubate at 25 °C for 30 min, and then determine the content according to the method for total glutathione.
[0099] The content of reduced glutathione (GSH) is equal to the total glutathione content minus the content of oxidized glutathione (GSSG).
[0100] Results of the determination of reduced glutathione (GSH) content:
[0101] like Figure 4As shown, at room temperature (0h), the content of reduced glutathione (GSH) in pepper leaves was significantly increased by 94.46% compared with the control group; after 6h of low temperature stress, the content of reduced glutathione (GSH) in pepper leaves was increased by 122.81% compared with the control group; after 12h of low temperature stress, the content of reduced glutathione (GSH) in pepper leaves was increased by 25.90% compared with the control group; after 24h of low temperature stress, the content of reduced glutathione (GSH) in pepper leaves was increased by 35.83% compared with the control group; with the extension of low temperature time, the content of reduced glutathione (GSH) in pepper leaves of the experimental group was significantly increased compared with the control group, indicating that dihydroporphyrin iron spray can enhance the cold resistance of pepper seedlings.
[0102] (v) Determination of antioxidant enzyme activity
[0103] Methods for determining antioxidant enzyme activity:
[0104] Take 0.1g of fresh leaves and grind the leaf tissue with 1ml of pre-cooled extraction solution using a pre-cooled pestle and mortar. Then centrifuge at 8000g for 10min at 4℃. Measure the absorbance of the supernatant using a visible spectrophotometer according to the instructions of the corresponding enzyme activity assay kit (manufactured by Solarbio Science & Technology Co., Ltd.) to calculate the activity of the antioxidant enzymes. Superoxide dismutase (SOD) absorbance was read at 560nm; physical peroxidase (POD) absorbance was read at 470nm.
[0105] Results of antioxidant enzyme activity assay:
[0106] like Figure 5a As shown, at room temperature (0h), the superoxide dismutase (SOD) activity in the experimental group increased by 92.72% compared with the control group; after 6h of low temperature stress, the superoxide dismutase (SOD) activity in the experimental group increased compared with the control group, but the difference was not significant; after 12h of low temperature stress, the superoxide dismutase (SOD) activity in the experimental group increased by 27.26% compared with the control group; after 24h of low temperature stress, the superoxide dismutase (SOD) activity in the experimental group increased by 60.81% compared with the control group, indicating that the dihydroporphyrin iron spray significantly increased the superoxide dismutase (SOD) activity in pepper leaves.
[0107] like Figure 5bAs shown, at room temperature (0h), the activity of peroxidase (POD) in the experimental group increased by 58.11% compared with the control group; after 6h of low temperature stress, the activity of peroxidase (POD) in the experimental group increased by 262.16% compared with the control group; after 12h of low temperature stress, the activity of peroxidase (POD) in the experimental group increased by 36.84% compared with the control group; and after 24h of low temperature stress, the activity of peroxidase (POD) in the experimental group increased by 60.81% compared with the control group. These results indicate that when pepper seedlings are subjected to low temperature stress, dihydroporphyrin iron spray can increase the activity of antioxidant enzymes in pepper leaves, thereby protecting the reactive oxygen metabolism system of peppers from damage and improving the low temperature resistance of pepper seedlings.
[0108] Example 4
[0109] This embodiment relates to the application of dihydroporphyrin iron or the low-temperature protection agent for oilseed and vegetable crops as described in Example 1 in the low-temperature resistance of rapeseed.
[0110] Rapeseed seedlings with similar growth were selected and divided into experimental and control groups.
[0111] During the seedling stage (3-5 leaf stage), the experimental group was sprayed with 0.2 μg / mL of dihydroporphyrin iron spray, while the control group was sprayed with water until the leaf surface was evenly covered with droplets. After spraying, the experimental and control groups were kept out of the light for 24 hours.
[0112] Twenty-four hours later, the experimental and control groups were placed in an artificial climate chamber for 4°C low-temperature stress treatment. At different time points after the low-temperature stress treatment (0h, 6h, 12h, 24h), 12 pots of rapeseed were randomly selected from the experimental and control groups for comparison.
[0113] from Figure 6 The results showed that after 48 hours of low-temperature stress treatment, the leaves of the control group plants showed severe wilting, while the experimental group plants only had a few leaf tips that wilted slightly, and most leaves were fully expanded, with the frost damage index decreasing by more than 40%.
[0114] Example 5
[0115] This embodiment is a supplementary embodiment to embodiment 4.
[0116] The rapeseed variety tested was “Ningza 1818”.
[0117] Rapeseed seedlings with similar growth were selected and divided into experimental and control groups.
[0118] The experimental group was sprayed with 0.2 μg / mL iron dihydroporphyrin spray multiple times during the seedling stage, the early stage of low temperature, the bolting stage, and the initial flowering stage, with an interval of 5-7 days between sprays. The control group was sprayed with water until the leaf surface was evenly covered with droplets.
[0119] from Figure 7a The results show that the stems of the experimental group were thicker during the seedling stage;
[0120] from Figure 7b The results show that during the overwintering period (low temperature), the experimental group had well-developed root systems, green leaf centers, more white roots, and milder frost damage symptoms.
[0121] from Figure 7c The results show that the number of primary branches in the experimental group increased significantly during the bolting stage;
[0122] from Figure 7d The results showed that during the initial flowering stage, the experimental group had more flowers, a significantly increased number of pods, and a yield increase of 22.4%.
[0123]
[0124] Table 2. Production increase data of iron dihydroporphyrin solution at low temperature in the experimental group.
[0125] The application of dihydroporphyrin iron in low-temperature resistance of oilseeds and vegetable crops, and the method for low-temperature resistance, of the present invention have at least the following beneficial effects:
[0126] 1) Treating oilseed and vegetable seedlings under low temperature stress with the plant low temperature resistance regulator containing dihydroporphyrin iron of the present invention can effectively reduce the chilling injury index, alleviate plasma membrane damage, increase the accumulation of osmotic regulators, enhance cold resistance, and improve antioxidant enzyme activity, thereby protecting the reactive oxygen metabolism system of oilseed and vegetable crops from damage and improving the low temperature resistance of oilseed and vegetable seedlings.
[0127] 2) The plant low-temperature resistance regulator containing dihydroporphyrin iron of the present invention has a certain stress resistance effect on oil crops and vegetable crops, and can reduce the chilling injury index of oil crops and vegetable crops, providing a new idea and reference for improving the low-temperature resistance of oil crops and vegetable crops.
[0128] The above description is merely a preferred embodiment of the present invention and does not limit the implementation and protection scope of the present invention. Those skilled in the art should realize that any equivalent substitutions and obvious changes made based on the description and illustrations of the present invention should be included within the protection scope of the present invention.
Claims
1. The application of dihydroporphyrin iron in low-temperature resistance of vegetable crops, characterized in that, The vegetable crop is chili pepper, and the dihydroporphyrin iron is a dihydroporphyrin iron solution diluted 500 to 1000 times based on a solution of 0.02 wt% soluble powder. Among them, iron dihydroporphyrin has at least one of the following effects: reducing the cold injury index, alleviating plasma membrane damage, increasing the accumulation of osmotic regulators, enhancing cold resistance, and improving antioxidant enzyme activity. One method for using iron dihydroporphyrin to protect vegetable crops from low temperatures includes the following steps: spraying the leaves of vegetable crops with iron dihydroporphyrin 24 to 48 hours before the vegetables experience low temperatures.