Tobacco root growth promoting agent and application thereof

Abstract

The invention relates to the field of agricultural chemicals, in particular to development and application of a root growth promoting agent for tobacco. The invention provides a tobacco root growth promoting agent. The tobacco root growth promoting agent is prepared from the following components in dosage: 1.9 to 2.1 g of alpha-pimacol, 1.4 to 1.6 g of compound sodium nitrophenolate, 0.18 to 0.22 g of indoleacetic acid, 0.18 to 0.22 g of hymexazol, 2.9 to 3.1 g of cane sugar, 0.18 to 0.22 g of diethyl aminoethyl hexanoate and 2.8 to 3.0 g of zinc sulfate. And 20 L of an acid-modified biochar leaching solution or a diluent of the acid-modified biochar leaching solution. The invention further provides application of the tobacco root growth promoting agent. When tobacco seedlings grow to a small cross stage, the root growth promoting agent is adopted for root irrigation, and the effect of promoting growth and development of root systems of the tobacco seedlings can be achieved.

Description

Technical Field

[0001] The invention relates to the field of agricultural chemicals, and in particular to the development and application of a root growth promoting agent for tobacco. Background Art

[0002] In agricultural production, tobacco is an important economic crop. Root promoters that can effectively promote the growth and development of tobacco roots have broad application prospects. Root promoters are plant growth regulators used to promote the growth and development of plant roots. They mainly work by changing the physiological metabolic process of plants and the balance of plant hormones. At the same time, acid-modified biochar extract, as a new type of soil improvement material liquid fertilizer, can significantly improve plant growth by improving soil structure and providing nutrients.

[0003] At present, many studies have clarified the role of water-soluble substances in biochar on plant growth. These substances are usually obtained by extracting biochar using water, acid or alkali as an extractant. (Lou et al, 2016) Soluble compounds were extracted from biochar using hot water, and it was found that even foliar spraying of this special ingredient could increase cabbage yield. (Sun et al, 2017) Biochar extract was obtained using hydrochloric acid and found to promote the germination of corn seeds. It was also found that wheat straw biochar extract using KOH solution as an extractant can not only improve the quality of garlic and strawberries but also have a positive effect on the physical and chemical properties of the soil (Zhuo Yalu, 2017). This may be because biochar changes the composition of soil microorganisms, partially affects the release rate of its hormone-like compounds, and promotes plant growth (Kolton et al, 2017). Recent studies have shown that spraying water extracts of biochar, like foliar spraying of fertilizers, can increase crop yields (Schmidt et al, 2020), and is a very promising agricultural liquid improver (Lou et al 2016). Studies have found that the complex mineral / organic nanoparticles contained in its biochar water extract can be used as nanofertilizer foliar sprays with the potential to promote plant growth and increase yield. Under natural conditions, the application of low-dose biochar water extract can improve the growth and physiological characteristics of lettuce in soilless culture media (Kumar et al, 2021).

[0004] Sun et al. 2017 used 0.1 mol / L hydrochloric acid to obtain biochar extract and found that corn biochar extract can promote the germination of corn seeds.

[0005] At present, the existing root promoters that can promote the growth of tobacco roots generally include "Dikang Food Safety No. 1" as mineral humus powder; "Yukant" as plant stress resistance inducer; "Puduoshou Magic Root" and other root promoters, but currently, root promoters that "combine nutrients and biostimulants" are also popular, such as "adding water-soluble topdressing and applying root promoters". Studies have shown that the use of water-soluble topdressing combined with Dikang Food Safety No. 1 and Yinkang can significantly promote the accumulation of dry matter in the early stage of flue-cured tobacco growth, significantly increase the accumulation of nitrogen and phosphorus in flue-cured tobacco, and effectively improve fertilizer absorption efficiency and production benefits. However, the disadvantage is that because its water-soluble fertilizer needs to go through special production processes and technologies, the production cost is much higher than that of ordinary fertilizers and conventional root promoters. Therefore, when adding root promoters, the whole process greatly increases the cost expenditure of tobacco farmers, and the whole process of applying water-soluble topdressing and root promoters becomes complicated, and the fertilizer needs to be prepared into a soluble solution and then combined with its conventional root promoter.

[0006] Therefore, it is very necessary to develop a liquid root promoter that can promote the growth of tobacco roots, which not only increases its biochar utilization pathway, but also enhances various physiological indicators of tobacco. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a development and application of a liquid root-promoting agent for tobacco.

[0008] In order to solve the above problems, the present invention provides a tobacco root growth promoting agent, which is composed of the following ingredients in the following amounts:

[0009] α-Naphthylacetic acid sodium 1.9~2.1g

[0010] Sodium nitrophenolate 1.4~1.6g

[0011] Indoleacetic acid 0.18~0.22g

[0012] Methadone 0.18~0.22g

[0013] Sucrose 2.9~3.1g

[0014] Aminoethyl hexanoate 0.18~0.22g

[0015] Zinc sulfate 2.8-3.0 g;

[0016] 20L of acid-modified biochar extract or diluted acid-modified biochar extract.

[0017] As the improvement of the tobacco root promoting agent of the present invention:

[0018] The preparation method of the acid-modified biochar extract is as follows: the rice husk biochar and the extractant are mixed in a dosage ratio of 1 g: 24-26 ml (preferably 1 g: 25 ml), shaken on a shaker for 23-25 ​​h (25±2° C., 100±20 rpm), and then filtered. The filtrate is passed through a 0.22 μm microporous filter membrane (organic nylon microporous filter membrane) to obtain an acid-modified biochar extract.

[0019] As a further improvement of the tobacco root promoting agent of the present invention: distilled water is added to the acid-modified biochar extract to obtain a diluted solution of the acid-modified biochar extract; the volume ratio of the distilled water: the acid-modified biochar extract = 49 to 99:1.

[0020] As a further improvement of the tobacco root promoting agent of the present invention: the extractant is a 0.018-0.022 mol / L phosphoric acid solution.

[0021] As a further improvement of the tobacco root accelerating agent of the present invention, it is composed of the following ingredients in the following amounts:

[0022] Sodium α-naphthylacetate 2.00g

[0023] Sodium nitrophenolate 1.50g

[0024] Indoleacetic acid 0.20g

[0025] Methadone 0.20g

[0026] Sucrose 3.00g

[0027] Aminoethyl hexanoate 0.20g

[0028] Zinc sulfate 2.90g

[0029] 20L of acid-modified biochar extract or diluted acid-modified biochar extract.

[0030] As a further improvement of the tobacco root growth promoting agent of the present invention: the purity of sodium α-naphthylacetate is ≥98%.

[0031] The present invention also provides the application of the tobacco root-promoting agent: when the tobacco seedlings grow to the small cross stage, the root-promoting agent is used to irrigate the roots.

[0032] The present invention provides the development and application of a tobacco root promoter, which has the function of promoting the growth and development of the root system of tobacco seedlings, thereby subsequently improving the yield and quality of tobacco leaves. The technology has feasibility and economic benefits, is suitable for the fields of planting and horticulture, and has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The specific implementation modes of the present invention are further described in detail below with reference to the accompanying drawings.

[0034] Figure 1 The present invention is a flow chart for preparing the acid-modified biochar extract;

[0035] Figure 2 This is a comparison of the morphology of 45d tobacco seedlings of a special root promoter with different dilution multiples;

[0036] Figure 3 This is a comparison chart of the effects of different treatments on the chlorophyll content of tobacco seedling leaves;

[0037] Figure 4 This is a comparison chart of the effects of different treatments on the SPAD value of tobacco seedling leaves;

[0038] Figure 5 This is a comparison chart of the effects of different treatments on the growth and development of tobacco seedlings at -60d (seedling stage: 60 days after sowing);

[0039] Figure 6 Comparison of the effects of different treatments on tobacco seedling biomass;

[0040] Figure 7 Comparison of root morphology of tobacco seedlings under different treatments;

[0041] Figure 8 Comparison of the effects of different treatments on the root volume and taproot length of tobacco seedlings;

[0042] Fig. 9 Comparison of the effects of different treatments on the total length of roots of different diameters of tobacco seedlings;

[0043] Fig.10 Comparison of the effects of different treatments on root activity of tobacco seedlings;

[0044] Fig.11 Comparison of the effects of different treatments on protective enzymes in tobacco seedling leaves;

[0045] Fig.11 In the figure, (a) to (c) show the effects of different treatments on SOD enzyme in tobacco seedling leaves, the effects of different treatments on POD enzyme in tobacco seedling leaves, and the effects of different treatments on NR enzyme in tobacco seedling leaves, respectively. DETAILED DESCRIPTION

[0046] The present invention is further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited thereto:

[0047] Example 1. Preparation of acid-modified biochar extract

[0048] Rice husk biochar and extractant (0.02 mol / L phosphoric acid solution) were prepared in proportion (1 g: 25 ml), and then shaken on a rotary shaker at 25 ± 2 ° C and 100 rpm for 24 hours. After the shaking was completed, the supernatant and the leaching residue (modified biochar) were separated by filtration. The supernatant was filtered through a 0.22 μm organic nylon microporous filter membrane and a circulating water vacuum pump. The filtrate obtained was the acid-modified biochar extract. The acid-modified biochar extract was transferred to a small white polyethylene bottle and then stored in a refrigerator (4 ° C) for further experimental analysis.

[0049] Rice husk biochar is commercially available, for example, from Henan Lize Environmental Protection Technology Co., Ltd.

[0050] The original solution of acid-modified biochar extract - S0;

[0051] 49 parts by volume of distilled water were added to 1 part by volume of the acid-modified biochar extract to prepare a 50-fold diluted acid-modified biochar extract, S50.

[0052] 99 parts by volume of distilled water were added to 1 part by volume of the acid-modified biochar extract to prepare a 100-fold diluted acid-modified biochar extract, S100.

[0053] The physical and chemical properties of the original solution of acid-modified biochar extract - S0, the 50-fold diluted acid-modified biochar extract - S50, the 100-fold diluted acid-modified biochar extract - S100 and distilled water are shown in Table 1.

[0054] Table 1. Physicochemical properties of acid-modified biochar extracts

[0055]

[0056] As shown in Table 1, the acid-modified biochar extract is an acidic liquid, and as the dilution multiple of the extract increases, the pH value of the extract gradually increases, while the electrical conductivity (EC) decreases with the increase of the dilution multiple.

[0057] Example 2-1, root promoting agent preparation:

[0058] The formula is shown in Table 2 below.

[0059] Table 2, root promoting agent preparation

[0060] Pharmacy Amount High purity (≧98%) α-naphthyl acetate sodium 2.00g Sodium nitrophenolate 1.50g Indoleacetic acid 0.20g Methadone 0.20g sucrose 3.00g Aminoethyl hexanoate 0.20g Zinc sulfate 2.90g Acid modified biochar extract (original solution S0) 20.0L

[0061] Example 2-2: The "acid-modified biochar extract (original solution S0)" in Example 2-1 is changed to "50 times diluted acid-modified biochar extract - S50", and the rest is the same as Example 2-1.

[0062] Example 2-3: The "acid-modified biochar extract (original solution S0)" in Example 2-1 is changed to "100-fold diluted acid-modified biochar extract - S100", and the rest is the same as Example 2-1.

[0063] Control group: The "acid-modified biochar extract (original solution S0)" in Example 2-1 was replaced with "distilled water", and the rest was the same as Example 2-1.

[0064] Experiment 1

[0065] 1. Experimental content:

[0066] This experiment was divided into 4 treatments, including 3 invention groups (T1-T3) and 1 control group, as shown in Table 3. Each treatment had 3 replicates of tobacco seedlings, with 20 plants in each replicate. The tested flue-cured tobacco variety was K326, which was provided by Yuxi Zhongyan Seed Co., Ltd. The floating seedling tray had a specification of 525mm×335mm×60mm, the inner diameter of the seedling hole was 24mm×24mm, and the seedling floating tray had a specification of 160 holes.

[0067] Before sowing, the floating trays were sterilized conventionally (i.e., disinfected by soaking in a bleaching powder solution at a ratio of 1:100 by weight), one tobacco seed was sown in each hole, and then the seedling holes were filled with a seedling medium (80% peat + 15% vermiculite + 5% perlite); each floating seedling tray was placed on a nutrient solution (14 L) containing 25 g of a tobacco seedling fertilizer (N:P 2 O 5 :K 2 O=18:12:13) and added about 14L distilled water.

[0068] According to the conventional fertilization method: fertilize twice during the seedling raising period, the first time when the seedlings are about 75% emerged, and the second time when the tobacco seedlings have 6-7 true leaves and the seedlings are about 10 cm tall. Each time you fertilize, pour out the original nutrient solution and replace it with a nutrient solution made by adding 25g of tobacco seedling fertilizer to 14L of distilled water. Keep the nutrient solution at 14L during the seedling raising process. When the water level drops, add distilled water to 14L and keep the same water level every day.

[0069] As common sense: the seedbed period can be divided into four growth periods, namely the emergence period (from sowing to emergence), the cross period (from emergence to cross, first entering the small cross period, and then entering the large cross period), the rooting period (from cross to small ear), and the seedling period (from small ear to seedling).

[0070] Thinning and transplanting should be carried out during the small cross stage of tobacco seedlings to keep the tobacco seedlings uniform. The management methods can refer to GB / T25241.1-2010 Technical Regulations for Intensive Tobacco Seedling Cultivation Part 1: Floating Seedling Cultivation.

[0071] When the tobacco seedlings grew to the small cross stage, root-stimulating agents were used for root irrigation, once every 7 days, for a total of 6 times; 200 ml of root-stimulating agent was used for each tobacco seedling each time; the seeds were sown on September 9 in the greenhouse nursery of Yunnan Agricultural University. The temperature in the nursery was in the range of 14-21°C, and the relative humidity was in the range of 35-91%.

[0072] Table 3 Experimental design

[0073]

[0074]

[0075] 2. Experimental measurement items:

[0076] 2.1) Determination of morphological indicators

[0077] Tobacco seedling growth period and agronomic traits determination (agronomic traits of tobacco seedlings were determined 45 days after sowing):

[0078] Refer to the industry standard YC / T 142-2010 Tobacco Agronomic Traits Survey; Plant height: use a ruler to measure the distance between the base of the tobacco seedling (foam board) and the top of the main stem, i.e. the growth point of the main stem; Stem diameter: measure the maximum circumference of the lower diameter of the cotyledon; use a SPAD-502 instrument to measure the chlorophyll SPAD value of the plant leaves. The fresh and dry weight of tobacco seedlings are weighed using a balance with an accuracy of 1 / 10000.

[0079] Determination of root architecture:

[0080] Epson Perfection V800 photo99 (Yunnan Tobacco Agricultural Science Research Institute) was used to measure root morphological parameters such as total root length, total root surface area, root volume, average diameter, number of root tips, number of branches, and three root diameter grades (0<L≤1.0mm small fine roots, 1.0mm<L≤2.0mm medium roots, and L≥2.00mm coarse roots), and WinRHIZO analysis system was used for calculation and analysis.

[0081] 2.2) Determination of physiological and biochemical indicators

[0082] Since the previous data of root activity, catalase, nitrate reductase and peroxidase were not significantly different, the data after 45 days of sowing were selected for analysis. At 9:00-10:00 on the 45th day after sowing, 5 plants were collected from each treatment to weigh the fresh weight of the aboveground part and the root system, and then the tobacco was put into the oven for 30 minutes at 105℃ and 48 hours at 75℃ to constant weight. After cooling in the oven, the dry weight of the aboveground part and the root system was weighed. In addition, 6 plants were randomly sampled from each treatment each time, and repeated 3 times. The root activity was measured respectively; the root activity was measured by triphenyltetrazolium chloride (TTC) method.

[0083] Determination of protective enzyme activities (SOD, POD, NR): Superoxide dismutase activity was determined by nitroblue tetrazolium method; peroxidase activity was determined by guaiacol method; nitrate reductase activity was determined by sulfonamide-naphthylamine colorimetric method. Root activity determination: Red tetrazolium (TTC) colorimetric method was used.

[0084] 3. Experimental results:

[0085] 3.1) Effects of different treatments on tobacco seedling growth and development (45 days after sowing):

[0086] Table 4 and Figure 2 As shown in the figure, compared with the control, the agronomic traits of tobacco seedlings in the T1 treatment decreased compared with the CK, and its stem height and maximum leaf area decreased by 3.25% and 7.05% respectively compared with the control; and with the increase of dilution multiples, the appearance growth indicators of tobacco seedlings showed a promoting effect, which was most obvious in the T3 treatment, with stem height, stem girth, and maximum leaf area increasing by 12.82%, 16.35%, and 23.11% respectively compared with CK. This shows that the special root promoter has a promoting effect on the growth of various agronomic traits of tobacco seedlings.

[0087] Table 4 Effects of different treatments on agronomic traits of tobacco seedlings

[0088]

[0089] 3.2) Effects of different dilution multiples of special root promoter on chlorophyll in tobacco seedling leaves (45 days after sowing)

[0090] Effects of different treatments on chlorophyll a and b in tobacco seedling leaves:

[0091] like Figure 3 As shown, the chlorophyll a content of each treatment is T3>T2>CK>T1, and the chlorophyll a content of T3 increased by 13.91% compared with the control; the chlorophyll b content of each treatment is T3>T2>CK>T1, and the increase of T3 treatment is 5.93% compared with CK; the total chlorophyll content is the highest in T3 treatment, and its total chlorophyll content increased by 11.50% compared with the control. Therefore, root irrigation of the substrate-specific root-promoting agent after dilution by 50-100 times is beneficial to chlorophyll synthesis.

[0092] Effects of different treatments on SPAD of tobacco seedling leaves:

[0093] like Figure 4 As shown in the figure, the SPAD value of tobacco leaves is consistent with the test results of chlorophyll a and b content. As the dilution multiple increases, the SPAD value of leaves also increases. Compared with the control, the SPAD value of T3 treatment increased by 9.32 percentage points. This shows that the special root promoter has a promoting effect on the chlorophyll content of tobacco seedling leaves after being diluted to a certain multiple.

[0094] 3.3) Effects of different treatments on the biomass accumulation of tobacco seedlings

[0095] A comprehensive comparison of the biomass of different parts of tobacco seedlings treated with different Figures 5-6 The aboveground fresh weight and dry weight biomass of T2 and T3 treatments were significantly higher than those of the control group, with fresh weight increasing by 32.57% and 63.49% respectively, and aboveground dry weight accumulation increasing by 61.76% and 105.88% respectively. The underground fresh and dry weight also showed this pattern. With the increase of the dilution multiple of the special root promoter, the accumulation of fresh and dry weight of tobacco seedlings can be promoted.

[0096] 3.4) Effects of different treatments with special root promoters on root morphological parameters of tobacco seedlings

[0097] Effects of different treatments on root architecture parameters of tobacco seedlings:

[0098] The morphological parameters of tobacco seedling root system are shown in Table 5 and Figure 7 The total root length and number of root tips were the highest in T3 treatment, reaching 315.59 mm and 2123.00 respectively, which were 41.32% and 152.14% higher than those in CK treatment. The root surface area and number of branches were the highest in T2 treatment, reaching 54.85 cm 2 and 5075.33, which were 32.33% and 40.45% higher than the control, respectively. In comprehensive comparison, the root morphological characteristics of tobacco seedlings treated with T2 and T3 were better than those of the control.

[0099] Table 5 Effects of different treatments on root architecture of tobacco seedlings

[0100]

[0101] Effects of different treatments on root volume and taproot length of tobacco seedlings:

[0102] like Figure 8 As shown in the figure, when the tobacco seedlings were transplanted for 45 days, the root volume and taproot length of the tobacco seedlings increased with the increase of the dilution multiple of the special root promoter, and the root volume and taproot length of the T3 treatment increased by 30.65% and 23.77% respectively compared with the CK treatment. This shows that the special root promoter has a promoting effect on the growth of tobacco roots after being diluted 100 times.

[0103] Effects of different treatments on the total length of roots of tobacco seedlings of different diameters:

[0104] The total length of roots of different diameters is shown in Fig. 9, with the increase of the dilution multiple of the special root-promoting agent, the effect on the total length of different root diameters was different. In the total length of fine roots of L≤0.5mm, 0.5mm≤L≤1.0mm and medium roots of 1.0mm<L≤2.0mm, the T3 treatment performed best, with an increase of 53.76%, 23.31% and 21.60% respectively compared with the control, and there was a significant difference; while the root length of different diameters in the T1 treatment was significantly lower than that of the other treatments. This shows that the application of a special root-promoting agent diluted a certain multiple has a promoting effect on the total root length of different diameters of the root system of tobacco seedlings, especially the total length of fine roots of L≤0.5mm and medium roots of 1.0mm<L≤2.0mm, with the largest increase.

[0105] Effects of different treatments on root activity of tobacco seedlings:

[0106] like Fig.10 As shown in the figure, the root activity of the special root promoter increased linearly with the increase of dilution multiples. The T1, T2, and T3 treatments were significantly higher than the control, and increased by 22.78%, 26.00%, and 47.78% respectively compared with the CK treatment. This shows that the application of root promoter liquid in the matrix can improve the root activity of tobacco seedlings.

[0107] Effects of different substrate treatments on protective enzymes in tobacco seedling leaves

[0108] Different treatments have different effects on SOD activity in tobacco seedling leaves Fig.11 a, The enzyme activity of T3 treatment was the highest, which was 43.90% higher than that of the control, followed by T2 treatment, and there was no significant difference between T1 treatment and CK treatment;

[0109] Leaf POD enzyme activity Fig.11 As shown in b, the POD enzyme activity in tobacco seedling leaves showed an overall increasing trend, among which the T3 treatment increased by 42.22% and 30.38% compared with the CK and T1 treatments, respectively.

[0110] The significant difference analysis of NR enzyme activity is shown in Fig.11 c. The NR enzyme activity in tobacco seedling leaves was in the order of T3>T2>CK>T1, and the T3 treatment increased by 273.03 percentage points compared with the CK treatment.

[0111] Comparative Example 1: The "0.02 mol / L phosphoric acid solution" in Example 1 was changed to "0.01 mol / L phosphoric acid solution", and the rest was the same as Example 1. The obtained "acid-modified biochar extract" was added with 99 parts by volume of distilled water as a 100-fold diluted acid-modified biochar extract. Then, the corresponding rooting agent was prepared according to Examples 2-3. The experiment was carried out according to the method described in Experiment 1 above, and its various indicators had no significant difference with CK.

[0112] Finally, it should be noted that the above examples are only some specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments, and there are many variations. All variations that can be directly derived or associated with the content disclosed by a person skilled in the art should be considered as the protection scope of the present invention.

Claims

1. A tobacco root growth promoting agent, characterized in that It is composed of the following ingredients in the following amounts: α-Naphthylacetic acid sodium 1.9~2.1g Sodium nitrophenolate 1.4~1.6g Indoleacetic acid 0.18~0.22g Methadone 0.18~0.22g Sucrose 2.9~3.1g Aminoethyl hexanoate 0.18~0.22g Zinc sulfate 2.8-3.0 g; 20L of acid-modified biochar extract or diluted acid-modified biochar extract.

2. The tobacco root growth promoting agent according to claim 1, characterized in that: The preparation method of the acid-modified biochar extract is as follows: after mixing the rice husk biochar and the extractant in a dosage ratio of 1g:24-26ml, shaking on a shaker for 23-25h, and then filtering, and the obtained filtrate is passed through a 0.22μm microporous filter membrane to obtain the acid-modified biochar extract.

3. The tobacco root growth promoting agent according to claim 2, characterized in that: Add distilled water to the acid-modified biochar extract to obtain a diluted solution of the acid-modified biochar extract; the volume ratio of the distilled water to the acid-modified biochar extract is 49 to 99:

1.

4. The tobacco root growth promoting agent according to any one of claims 1 to 3, characterized in that: The extractant is a 0.018-0.022 mol / L phosphoric acid solution.

5. The tobacco root growth promoting agent according to claim 4, characterized in that The following ingredients are used in the following amounts composition: α-Naphthylacetic acid sodium 2g Sodium nitrophenolate 1.5g Indoleacetic acid 0.2g Methadone 0.2g Sucrose 3g Aminoethyl hexanoate 0.2g Zinc sulfate 2.9 g; 20L of acid-modified biochar extract or diluted acid-modified biochar extract.

6. The tobacco root growth promoting agent according to any one of claims 1 to 5, characterized in that: The purity of sodium α-naphthyl acetate is ≥98%.

7. The application of tobacco root-promoting agent is characterized by: When the tobacco seedlings grow to the small cross stage, start using root-promoting agents to irrigate the roots.

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