Tobacco fertilizer composition capable of resisting diseases and increasing yield under cadmium stress and application of tobacco fertilizer composition

Abstract

The invention provides a tobacco fertilizer composition capable of resisting diseases and increasing yield under cadmium stress. The tobacco fertilizer composition comprises a microbial base fertilizer and a water-soluble topdressing fertilizer, the water-soluble additional fertilizer is prepared from the following components in parts by weight: 350 to 400 parts of eleusine indica aqueous extract, 100 parts of potassium nitrate, 80 to 120 parts of urea, 150 to 180 parts of calcium nitrate, 40 parts of sodium alginate, 20 parts of water-soluble starch and 30 parts of polyglutamic acid; the preparation method of the microbial fertilizer base fertilizer comprises the following steps: fermenting matteuccia struthiopteris water extract residues, pleurotus eryngii residues and corn straws as fermentation substrates and bacillus subtilis B115 as zymophyte according to a weight ratio of (1: 2)-(4: 1), so as to obtain the microbial fertilizer base fertilizer. The microbial base fertilizer and the water-soluble topdressing fertilizer in the tobacco fertilizer composition provided by the invention are matched with each other, so that the tobacco growth can be promoted and the tobacco bacterial wilt can be effectively prevented and treated in a cadmium stress environment.

Description

Technical Field

[0001] The invention belongs to the technical field of organic fertilizers, relates to a special fertilizer technology for tobacco, and particularly relates to a tobacco fertilizer composition capable of resisting disease and increasing yield under cadmium stress and application thereof. Background Art

[0002] Cadmium is not an essential nutrient for plant growth and development. The presence of cadmium will interfere with the normal physiological processes of plants such as respiration, transpiration, photosynthesis, and mineral and water absorption, leading to yellowing of plant leaves, slowed growth, reduced biomass, and even death.

[0003] Research has yielded some results on promoting tobacco growth under cadmium stress. For example, a specialized functional fertilizer developed by Guangxi China Tobacco, by optimizing the nitrogen, phosphorus, and potassium ratio (N:P2O5:K2O = 1:0.5:3) and combining humic acid and trace elements, has increased tobacco leaf yield by 15% under cadmium stress, significantly improving the balance of chemical composition. Furthermore, functional strains such as Bacillus velezensis have been found to reduce cadmium bioavailability and alleviate oxidative stress by secreting siderophores and organic acids. Furthermore, the combination of corn straw biochar and zinc / potassium foliar fertilizers has been shown to significantly reduce cadmium content in tobacco leaves.

[0004] However, people have not yet achieved ideal research results in developing tobacco-specific fertilizers that can not only promote tobacco growth under cadmium stress environments, but also effectively prevent and control tobacco diseases. Summary of the Invention

[0005] In view of the defects of the prior art, the object of the present invention is to provide a fertilizer composition that can be applied as a fertilizer and has a good anti-disease effect; and can also promote tobacco growth under cadmium stress environment.

[0006] The present invention provides the following technical solutions:

[0007] A tobacco fertilizer composition for resisting disease and increasing yield under cadmium stress, comprising a microbial fertilizer as a base fertilizer and a water-soluble fertilizer as a topdressing fertilizer;

[0008] The water-soluble fertilizer for topdressing comprises, by weight, 350-400 parts of water extract of Goosegrass, 100 parts of potassium nitrate, 80-120 parts of urea, 150-180 parts of calcium nitrate, 40 parts of sodium alginate, 20 parts of water-soluble starch, and 30 parts of polyglutamic acid;

[0009] The preparation method of the microbial fertilizer base comprises: using fern pod extract residue, king oyster mushroom residue and corn straw as fermentation substrates in a weight ratio of 1:2 to 4:1, and fermenting with Bacillus subtilis B115 as a fermentation bacterium to obtain the microbial fertilizer base; the fern pod extract residue is a residue phase obtained after fern pod extract is extracted with water; the preservation number of the Bacillus subtilis B115 is CGMCC NO.1210.

[0010] Preferably, the water-soluble fertilizer topdressing comprises, by weight, 400 parts of Goosegrass water extract, 100 parts of potassium nitrate, 100 parts of urea, 160 parts of calcium nitrate, 40 parts of sodium alginate, 20 parts of water-soluble starch, and 30 parts of polyglutamic acid.

[0011] Preferably, when preparing the microbial fertilizer base fertilizer, the preparation method of the water extract residue of the pod fern is: wash the pod fern, chop it, add it to water 5 times the weight of the pod fern, extract it at 80°C for 4 hours, and filter the filtrate; add the filter residue to water 3 times the weight of the filter residue, extract it at 80°C for 4 hours, and filter the residue phase.

[0012] Preferably, when preparing the microbial fertilizer base, the weight ratio of the fern water extract residue, Pleurotus eryngii residue and corn straw is 1:3:1.

[0013] Preferably, when preparing the microbial fertilizer base, when inoculating the Bacillus subtilis B115, the inoculation amount is 5%.

[0014] Preferably, when preparing the microbial fertilizer base, the fermentation starting temperature is 30° C. and the fermentation time is 72 hours.

[0015] The present invention also provides application of the tobacco fertilizer composition for resisting disease and increasing yield under cadmium stress in tobacco planting.

[0016] Specifically, when applying, when applying the microbial fertilizer as base fertilizer, 80 g is applied to each tobacco plant as base fertilizer; when applying the water-soluble fertilizer as topdressing, 200 mL is sprayed to each tobacco plant as topdressing.

[0017] Specifically, during application, after applying the microbial fertilizer as base fertilizer, the water-soluble fertilizer is sprayed as topdressing on the seventh day.

[0018] Specifically, when applying, after the first spraying of the water-soluble fertilizer as a topdressing, spray once every 10 days.

[0019] Beneficial effects of the present invention:

[0020] The tobacco fertilizer composition provided by the present invention combines a microbial fertilizer base and a water-soluble fertilizer topdressing agent to promote tobacco growth and effectively prevent tobacco bacterial wilt in cadmium-stressed environments. The composition not only prevents tobacco blight but is also suitable for tobacco cultivation in soils with mild cadmium stress, demonstrating its potential for industrial utilization. DETAILED DESCRIPTION

[0021] The present invention is described in detail below through examples. It is necessary to point out that the following examples are only used to further illustrate the present invention and are not to be construed as limiting the scope of protection of the present invention. Non-essential improvements and adjustments made by those skilled in the art based on the above-mentioned invention still fall within the scope of protection of the present invention.

[0022] Example 1

[0023] 1. Preparation of microbial fertilizer base

[0024] 1.1. Preparation of Pteris viridis aqueous extract

[0025] Wash the fern and chop it into 5-7 mm pieces. Add it into water 5 times the weight of the fern, extract it at 80°C for 4 hours, and filter the filtrate. Add the filter residue into water 3 times the weight of the filter residue, extract it at 80°C for 4 hours, filter the residue phase, and control the water content at 10-12% w / w.

[0026] 1.2 King Oyster Mushroom residue: purchased from Huamo (Shandong) Biotechnology Co., Ltd.

[0027] 1.3 Corn straw: collected by local farmers.

[0028] 1.4 Configuration of fermentation substrate

[0029] The water extract residue of Pteris podioides, Pleurotus eryngii residue (purchased from Huamo (Shandong) Biotechnology Co., Ltd.) and corn stalks (collected from local farmers) were mixed in a weight ratio of 1:3:1, and the water content was controlled to 20% w / w by spraying water.

[0030] 1.5 Fermentation bacteria

[0031] Bacillus subtilis B115, with a deposit number of CGMCC NO.1210, is a publicly available strain purchased from the China General Microbiological Culture Collection Center.

[0032] 1.6 Fermentation plan

[0033] Prepare the fermentation substrate, inoculate the fermentation bacteria at an inoculum size of 5%, start fermentation at 30°C, and control the fermentation time to be 72 hours.

[0034] 2. Preparation of Water-soluble Fertilizer for Topdressing

[0035] 2.1 Preparation of Eleutherodactyla serrata aqueous extract

[0036] Wash and chop the Herba Coleopterae (Herba Coleopterae) into 5-7 mm pieces, add the Herba Coleopterae (Herba Coleopterae) into 5 times the weight of water, extract at 80°C for 4 hours, and filter to obtain the filtrate; add the filter residue into 3 times the weight of water at 80°C, extract at 4 hours, and filter to obtain the filtrate; combine the two filtrates, remove the water by vacuum rotary evaporation to obtain a solid powder.

[0037] 2.2 Configuration of water-soluble fertilizer topdressing

[0038] According to weight parts, 400 parts of water extract of Goosegrass, 100 parts of potassium nitrate, 100 parts of urea, 160 parts of calcium nitrate, 40 parts of sodium alginate, 20 parts of water-soluble starch and 30 parts of polyglutamic acid are mixed to obtain the product.

[0039] Example 2

[0040] Compared with Example 1, the difference is that when preparing the microbial fertilizer base fertilizer, the addition ratio of the water extract residue of the pod fern, the oyster mushroom residue and the corn straw is 1:2:1, and the raw material ratio in the water-soluble fertilizer topdressing is changed. The rest is the same as Example 1. The specific scheme is as follows:

[0041] 1. Preparation of microbial fertilizer base

[0042] 1.1. Preparation of Pteris viridis aqueous extract

[0043] Wash the fern and chop it into 5-7 mm pieces. Add it into water 5 times the weight of the fern, extract it at 80°C for 4 hours, and filter the filtrate. Add the filter residue into water 3 times the weight of the filter residue, extract it at 80°C for 4 hours, filter the residue phase, and control the water content at 10-12% w / w.

[0044] 1.2 King Oyster Mushroom residue: purchased from Huamo (Shandong) Biotechnology Co., Ltd.

[0045] 1.3 Corn straw: collected by local farmers.

[0046] 1.4 Configuration of fermentation substrate

[0047] The water extract residue of Pteris podioides, Pleurotus eryngii residue (purchased from Huamo (Shandong) Biotechnology Co., Ltd.) and corn stalks (collected from local farmers) were mixed in a weight ratio of 1:2:1, and the water content was controlled to 20% w / w by spraying water.

[0048] 1.5 Fermentation bacteria

[0049] Bacillus subtilis B115, with a deposit number of CGMCC NO.1210, is a publicly available strain purchased from the China General Microbiological Culture Collection Center.

[0050] 1.6 Fermentation plan

[0051] Prepare the fermentation substrate, inoculate the fermentation bacteria at an inoculum size of 5%, start fermentation at 30°C, and control the fermentation time to be 72 hours.

[0052] 2. Preparation of Water-soluble Fertilizer for Topdressing

[0053] 2.1 Preparation of Eleutherodactyla serrata aqueous extract

[0054] Wash and chop the Herba Coleopterae (Herba Coleopterae) into 5-7 mm pieces, add the Herba Coleopterae (Herba Coleopterae) into 5 times the weight of water, extract at 80°C for 4 hours, and filter to obtain the filtrate; add the filter residue into 3 times the weight of water at 80°C, extract at 4 hours, and filter to obtain the filtrate; combine the two filtrates, remove the water by vacuum rotary evaporation to obtain a solid powder.

[0055] 2.2 Configuration of water-soluble fertilizer topdressing

[0056] According to weight parts, 350 parts of water extract of Eleutherodactyla serrata, 100 parts of potassium nitrate, 80 parts of urea, 180 parts of calcium nitrate, 40 parts of sodium alginate, 20 parts of water-soluble starch and 30 parts of polyglutamic acid are mixed to obtain the product.

[0057] Example 3

[0058] Compared with Example 1, the difference is that when preparing the microbial fertilizer base fertilizer, the addition ratio of the water extract residue of the pod fern, the oyster mushroom residue and the corn straw is 1:4:1, and the raw material ratio in the water-soluble fertilizer topdressing is changed. The rest is the same as Example 1. The specific scheme is as follows:

[0059] 1. Preparation of microbial fertilizer base

[0060] 1.1. Preparation of Pteris viridis aqueous extract

[0061] Wash the fern and chop it into 5-7 mm pieces. Add it into water 5 times the weight of the fern, extract it at 80°C for 4 hours, and filter the filtrate. Add the filter residue into water 3 times the weight of the filter residue, extract it at 80°C for 4 hours, filter the residue phase, and control the water content at 10-12% w / w.

[0062] 1.2 King Oyster Mushroom residue: purchased from Huamo (Shandong) Biotechnology Co., Ltd.

[0063] 1.3 Corn straw: collected by local farmers.

[0064] 1.4 Configuration of fermentation substrate

[0065] The water extract residue of Pteris podioides, Pleurotus eryngii residue (purchased from Huamo (Shandong) Biotechnology Co., Ltd.) and corn stalks (collected from local farmers) were mixed in a weight ratio of 1:2:1, and the water content was controlled to 20% w / w by spraying water.

[0066] 1.5 Fermentation bacteria

[0067] Bacillus subtilis B115, with a deposit number of CGMCC NO.1210, is a publicly available strain purchased from the China General Microbiological Culture Collection Center.

[0068] 1.6 Fermentation plan

[0069] Prepare the fermentation substrate, inoculate the fermentation bacteria at an inoculum size of 5%, start fermentation at 30°C, and control the fermentation time to be 72 hours.

[0070] 2. Preparation of Water-soluble Fertilizer for Topdressing

[0071] 2.1 Preparation of Eleutherodactyla serrata aqueous extract

[0072] Wash and chop the Herba Coleopterae (Herba Coleopterae) into 5-7 mm pieces, add the Herba Coleopterae (Herba Coleopterae) into 5 times the weight of water, extract at 80°C for 4 hours, and filter to obtain the filtrate; add the filter residue into 3 times the weight of water at 80°C, extract at 4 hours, and filter to obtain the filtrate; combine the two filtrates, remove the water by vacuum rotary evaporation to obtain a solid powder.

[0073] 2.2 Configuration of water-soluble fertilizer topdressing

[0074] According to weight parts, 380 parts of water extract of Eleutherodactyla serrata, 100 parts of potassium nitrate, 120 parts of urea, 150 parts of calcium nitrate, 40 parts of sodium alginate, 20 parts of water-soluble starch and 30 parts of polyglutamic acid are mixed to obtain the product.

[0075] Comparative Example 1

[0076] No corn stalks were added to the fermentation substrate, and the rest was the same as in Example 1. The fermentation substrate was specifically composed of: a mixture of Pteris chinensis water extract residue and Pleurotus eryngii residue (purchased from Huamo (Shandong) Biotechnology Co., Ltd.) at a weight ratio of 1:3, and water was sprayed to control the water content to 20% w / w.

[0077] Comparative Example 2

[0078] The fermentation substrate was prepared in the same manner as in Example 1 except that the proportions of the aqueous extract of fern fern, king oyster mushroom residue, and corn stalks were different. The fermentation substrate was prepared as follows: the aqueous extract of fern fern, king oyster mushroom residue (purchased from Huamo (Shandong) Biotechnology Co., Ltd.), and corn stalks (collected from local farmers) were mixed in a weight ratio of 1:1:1, and the water content was controlled to 20% w / w by spraying water.

[0079] Comparative Example 3

[0080] In the fermentation substrate, the aqueous extract of Eleutherodactylus spp. was used to replace the aqueous extract of Pteris spp., and the rest was the same as in Example 1. The aqueous extract of Eleutherodactylus spp. was prepared by washing and chopping the Eleutherodactylus spp. (5-7 mm pieces), adding the Eleutherodactylus spp. to water 5 times the weight of Pteris spp., extracting at 80° C. for 4 hours, and filtering the filtrate; adding the filter residue to water 3 times the weight of the filter residue, extracting at 80° C. for 4 hours, filtering the residue phase, and controlling the water content to be 10-12% w / w.

[0081] Preliminary Experimental Example 1

[0082] While investigating the impact of using a water extract of Pteris chinensis as a raw material for tobacco water-soluble fertilizer on disease resistance, the inventors discovered that it can improve the control of tobacco bacterial wilt to a certain extent (a separate patent application has been filed for this invention). Based on this, the inventors further investigated the effects of this water extract on tobacco growth under heavy metal cadmium stress. The following is a detailed experimental plan and results.

[0083] 1. Experimental Plan

[0084] Cadmium acetate was added to soil to a concentration of 5 mg / kg to create the cadmium-contaminated soil used in the experiment. The cadmium-contaminated soil was then potted, with 10 kg of soil per pot. Tobacco (Yunyan 87, the same tobacco variety used in other experimental schemes in this invention unless otherwise specified) was transplanted, with one healthy tobacco seedling per pot. After transplanting, a flue-cured tobacco compound fertilizer (produced by Hubei Xiangqing Fertilizer Co., Ltd.) was applied as a base fertilizer, with 80 g per pot applied.

[0085] Experimental group: Seven days after transplanting, water-soluble fertilizer was sprayed once, at a rate of 200 mL per pot. Thereafter, spraying was continued every 10 days at the same rate. The water-soluble fertilizer used in this pilot study was a mixture of a Pteris fasciata aqueous extract and a commercially available conventional water-soluble fertilizer, in a weight ratio of 3:7. The fertilizer was diluted with 100 times the weight of water. The commercially available conventional water-soluble fertilizer, purchased from Guizhou Qiannan Jinfu Co., Ltd., had a N:P₂O₅:K₂O ratio of 22:14:10 and was diluted with 100 times the weight of water. The Pteris fasciata aqueous extract was prepared by washing and chopping the Pteris fasciata into 5-7 mm pieces, adding the mixture to a volume of water five times the weight of the Pteris fasciata, extracting at 80°C for four hours, and filtering the filtrate. The residue was then added to a volume of water three times the weight of the residue, extracting at 80°C for four hours, and filtering the filtrate. The two filtrates were combined and the water removed by vacuum rotary evaporation to yield a solid powder.

[0086] Control group: The spraying system was the same as that of the experimental group, except that the water-soluble fertilizer consisting of the water extract of Pteris viridis and commercially available conventional water-soluble fertilizer was replaced by commercially available conventional water-soluble fertilizer.

[0087] On the 80th day after transplanting, the tobacco plants were measured for plant height, stem girth, leaf number, maximum leaf area (maximum leaf length × maximum leaf width × 0.6345), and biomass. Samples were also taken for determination of chlorophyll, peroxidase (POD), superoxide dismutase (SOD), and malondialdehyde (MDA). The results are shown in Table 1.

[0088] Table 1

[0089] Experimental group control group Plant height (cm) 72.5 72.3 Stem circumference (cm) 9.7 9.6 Number of blades 18.6 18.4 <![CDATA[Maximum leaf area (cm 2 )]]> 479.4 475.2 Biomass (g) 29.8 29.6 Chlorophyll (μg / g) 2.2 2.1 POD (U / g) 45.9 46.2 SOD (U / g) 235.5 237.6 MDA (μg / g) 2.2 2.3

[0090] As shown in Table 1, under cadmium stress, the addition of a water extract of Pteris chinensis to conventional commercially available water-soluble fertilizers had no significant effect on agronomic traits or the content of related components. This suggests that while the addition of a water extract of Pteris chinensis has some control effect on tobacco bacterial wilt, it has no significant effect on tobacco growth under cadmium stress.

[0091] Preliminary Experiment Example 2

[0092] In a separate patent application filed by the inventors, the effects of adding a water extract of Pteris cerifera and a water extract of Eleutherodactyla serrata on the prevention and treatment of tobacco bacterial wilt were investigated, and the combination of the two extracts was found to have a synergistic effect. In this preliminary experiment, the inventors used a water-soluble fertilizer consisting of a water extract of Pteris cerifera, a water extract of Eleutherodactyla serrata, and a commercially available conventional water-soluble fertilizer in a weight ratio of 1.5:1.5:7, replacing the water-soluble fertilizer in Preliminary Experimental Example 1 as the experimental group. The control group followed the same control group as in Preliminary Experimental Example 1.

[0093] Among them, the preparation method of the water extract of Goosegrass is as follows: wash the Goosegrass, chop it into 5-7 mm pieces, add it to water 5 times the weight of the Pteris viridis, extract it at 80°C for 4 hours, and filter the filtrate; add the filter residue to water 3 times the weight of the filter residue, extract it at 80°C for 4 hours, and filter the filtrate; combine the two filtrates, remove water by vacuum rotary evaporation, and obtain a solid powder.

[0094] The experiment was carried out in the potted plant test method of Preliminary Experimental Example 1, and the data of plant height, stem girth, number of leaves, maximum leaf area, biomass, chlorophyll, peroxidase, superoxide dismutase, and malondialdehyde were recorded. The results are shown in Table 2.

[0095] Table 2

[0096] Experimental group control group Plant height (cm) 72.6 72.8 Stem circumference (cm) 9.5 9.4 Number of blades 18.8 19.1 <![CDATA[Maximum leaf area (cm 2 )]]> 481.5 480.3 Biomass (g) 30.3 30.2 Chlorophyll (μg / g) 2.2 2.1 POD (U / g) 46.3 46.9 SOD (U / g) 237.7 239.4 MDA (μg / g) 2.2 2.3

[0097] As shown in Table 2, the application of water-soluble fertilizer consisting of water extracts of Pteris viridis, water extracts of Goosegrass and conventional commercial water-soluble fertilizers had no significant effect on tobacco growth under cadmium stress.

[0098] Preliminary Experiment Example 3

[0099] Since the water-soluble fertilizers in Preliminary Experimental Examples 1 and 2 had no effect on tobacco growth under cadmium stress, the inventors considered developing a new type of base fertilizer. Considering that the preparation of the water extract of Pteris chinensis produces Pteris chinensis water extract residue, and plant extract residues are often used to prepare microbial fertilizers, the inventors investigated the use of Pteris chinensis water extract residue to prepare a base fertilizer for microbial fertilizers.

[0100] (1) Preparation of microbial fertilizer base

[0101] 1. Preparation of Pteris viridis Water Extract

[0102] Wash the fern and chop it into 5-7 mm pieces. Add it into water 5 times the weight of the fern, extract it at 80°C for 4 hours, and filter the filtrate. Add the filter residue into water 3 times the weight of the filter residue, extract it at 80°C for 4 hours, filter the residue phase, and control the water content at 10-12% w / w.

[0103] 2. Configuration of fermentation substrate

[0104] The water extract residue of Pteris podioides, Pleurotus eryngii residue (purchased from Huamo (Shandong) Biotechnology Co., Ltd.) and corn stalks (collected from local farmers) were mixed in a weight ratio of 1:3:1, and the water content was controlled to 20% w / w by spraying water.

[0105] 3. Fermentation bacteria

[0106] Bacillus subtilis B115, with the deposit number CGMCC NO.1210, was purchased from China General Microbiological Culture Collection Center.

[0107] 4. Fermentation plan

[0108] Prepare the fermentation substrate, inoculate the fermentation bacteria at an inoculum size of 5%, start fermentation at 30°C, and control the fermentation time to be 72 hours.

[0109] (2) Potted plant experiment

[0110] In this preliminary experimental example, the base fertilizer in Preliminary Experimental Example 1 was adjusted to the microbial fertilizer base fertilizer prepared in this preliminary experimental example, and the water-soluble fertilizer in Preliminary Experimental Example 1 was used. On this basis, the experimental group and control group were set up with reference to Preliminary Experimental Example 1. The experiment was conducted with reference to the potted plant test method of Preliminary Experimental Example 1, and data on plant height, stem girth, number of leaves, maximum leaf area, biomass, chlorophyll, peroxidase, superoxide dismutase, and malondialdehyde were recorded. The results are shown in Table 3.

[0111] Table 3

[0112] Experimental group control group Plant height (cm) 80.6 78.4 Stem circumference (cm) 11.1 10.2 Number of blades 20.0 19.6 <![CDATA[Maximum leaf area (cm 2 )]]> 556.7 523.5 Biomass (g) 31.4 30.5 Chlorophyll (μg / g) 2.3 2.2 POD (U / g) 35.2 39.4 SOD (U / g) 209.6 221.3 MDA (μg / g) 2.1 2.2

[0113] As shown in Table 3, the microbial fertilizer base fertilizer of this pre-experimental example has an improvement effect on both the agronomic traits of tobacco and the content of related components compared with pre-experimental example 1. At the same time, by comparing the data of the experimental group and the control group of this pre-experimental example, it can also be found that the microbial fertilizer base fertilizer and the water-soluble fertilizer in this pre-experimental example have a certain synergistic effect in resisting cadmium stress.

[0114] Preliminary Experiment Example 4

[0115] Inspired by the preliminary experimental example 3, the inventors investigated the effect of the combined fertilizer on the prevention and control of tobacco bacterial wilt.

[0116] Experimental group: Take the soil with 100% bacterial wilt incidence as potted test soil, use 10kg soil per pot, transplant one tobacco seedling per pot, and use the microbial fertilizer base fertilizer prepared in this pre-experimental example as base fertilizer after transplanting tobacco, and apply 80g per pot; then spray the water-soluble fertilizer prepared in pre-experimental example 1 once on the 7th day after transplanting, and the spraying amount is 200mL per pot, and then spray once every 10 days, and the spraying amount is the same as before.

[0117] Control group 1: Unlike the experimental group, the base fertilizer of the experimental group was replaced with a special compound fertilizer for flue-cured tobacco (produced by Hubei Xiangqing Fertilizer Co., Ltd.), and the water-soluble fertilizer was replaced with a commercially available conventional water-soluble fertilizer (purchased from Guizhou Qiannan Jinfu Co., Ltd., N:P2O5:K2O=22:14:10).

[0118] Control group 2: Different from the experimental group, the base fertilizer of the experimental group was replaced by a special compound fertilizer for flue-cured tobacco (produced by Hubei Xiangqing Fertilizer Co., Ltd.) in the control group 2.

[0119] The incidence rate, disease index and control effect of tobacco bacterial wilt were investigated. The experimental results are shown in Table 4.

[0120] Incidence rate = number of diseased plants / total number of surveyed plants × 100%.

[0121] The disease index is investigated according to the tobacco industry standard tobacco disease classification and investigation method:

[0122] Level 0: All plants are disease-free;

[0123] Level 1: There are occasional chlorotic spots on the stem, or a few leaves wither on the side with streaks;

[0124] Level 2: There are black streaks on the stem but they have not yet reached the top, or more than half of the leaves on the diseased side are withered;

[0125] Level 3: Black streaks on the stem reach the top of the plant, or more than 2 / 3 of the leaves on the diseased side wilt; Level 4: The diseased plant is basically dead.

[0126] Disease index = [∑(disease level × number of strains at this level) / (highest level × total number of strains)] × 100.

[0127] Control effect = (control disease index - treatment disease index) / control disease index × 100%.

[0128] Table 4

[0129]

[0130] As shown in Table 4, the microbial fertilizer base fertilizer in this preliminary experimental example and the water-soluble fertilizer used in preliminary experimental example 1 also have a synergistic effect in preventing and controlling tobacco bacterial wilt, and can achieve a prevention efficiency of 66.4%.

[0131] Through Preliminary Experiments 1 to 4, the inventors have developed a fertilizer combination that exhibits positive effects in both resisting cadmium stress and controlling bacterial wilt. However, the positive effects achieved are still not satisfactory, with some shortcomings in both promoting tobacco growth and controlling bacterial wilt. Based on this, the inventors further adjusted the fertilizer formula and improved the technical solution. See the experimental examples of this invention for details.

[0132] Experimental Example 1

[0133] With reference to the potting scheme of Preliminary Experimental Example 1, the fertilizer compositions of Examples 1 to 3 and Comparative Examples 1 to 3 were examined for their effects on tobacco growth and control of tobacco bacterial wilt.

[0134] The microbial fertilizer base fertilizer and water-soluble fertilizer topdressing in the fertilizer compositions of Examples 1 to 3 and Comparative Examples 1 to 3 were used as base fertilizer and topdressing, respectively. Cadmium acetate was added to the soil so that the cadmium acetate content in the soil was 5 mg / kg to prepare cadmium-contaminated soil for the test. The cadmium-contaminated soil was potted, with 10 kg per pot. When transplanting tobacco, one healthy tobacco seedling was transplanted per pot, and 80 g of base fertilizer was applied to each pot after transplanting the tobacco. Topdressing was sprayed once on the 7th day after transplanting, with a spraying amount of 200 mL per pot, and then sprayed once every 10 days, with the same spraying amount as before.

[0135] The spraying system of the control group was the same as that of the aforementioned groups, except that the base fertilizer used in each group was replaced by the tobacco-specific compound fertilizer in Pre-Experimental Example 1, and the topdressing used in each group was replaced by the commercially available conventional water-soluble fertilizer in Pre-Experimental Example 1.

[0136] The experiment was conducted according to the protocol of Preliminary Experiment Example 1, and data on plant height, stem girth, number of leaves, maximum leaf area, biomass, chlorophyll, peroxidase, superoxide dismutase, and malondialdehyde were recorded. The experimental results are shown in Table 5.

[0137] Table 5

[0138]

[0139] As shown in Table 5, although in Preliminary Experimental Example 3, the inventors found that when the microbial fertilizer base fertilizer prepared in Preliminary Experimental Example 3 and the water-soluble fertilizer used in Preliminary Experimental Example 1 were used as topdressing, a certain anti-cadmium stress effect could be obtained and the growth performance of tobacco was promoted. However, by comparing the data of Examples 1 to 3 of the present invention with those of Preliminary Experimental Example 3, it can be seen that the presence of the Pteris chinensis water extract in the topdressing had a certain antagonistic effect with the Goosegrass water extract and the microbial fertilizer base fertilizer in terms of anti-cadmium stress. When the Pteris chinensis water extract was removed from the topdressing, the effect of the tobacco fertilizer composition of the present invention in terms of anti-cadmium stress was significantly improved.

[0140] In addition, it is worth noting that when preparing the microbial fertilizer base fertilizer, straw was not added as a substrate raw material, and the effect on cadmium stress resistance was even worse than that of the control group, which suggests that there is a slight antagonistic effect between the microbial fertilizer base fertilizer and the water-soluble fertilizer topdressing in Comparative Example 1. At the same time, as shown in Comparative Examples 2 and 3, when the fermentation substrate is adjusted, the resulting fertilizer combination has no promoting effect on tobacco cultivation under cadmium stress environment compared with the control group.

[0141] With reference to Preliminary Experimental Example 4, the inventors conducted experiments on the prevention and treatment of bacterial wilt on Examples 1 to 3 and Comparative Examples 1 to 3. In the control group, the microbial fertilizer base fertilizer of each group was replaced with a special compound fertilizer for flue-cured tobacco (produced by Hubei Xiangqing Fertilizer Co., Ltd.), and the water-soluble fertilizer topdressing was replaced with a commercially available conventional water-soluble fertilizer (purchased from Guizhou Qiannan Jinfu Co., Ltd., N:P2O5:K2O=22:14:10).

[0142] The experimental results are shown in Table 6.

[0143] Table 6

[0144]

Claims

1. A tobacco fertilizer composition for disease resistance and yield increase under cadmium stress, characterized in that: The composition comprises a microbial fertilizer base fertilizer and a water-soluble fertilizer topdressing; The water-soluble fertilizer for topdressing comprises, by weight, 350-400 parts of water extract of Goosegrass, 100 parts of potassium nitrate, 80-120 parts of urea, 150-180 parts of calcium nitrate, 40 parts of sodium alginate, 20 parts of water-soluble starch, and 30 parts of polyglutamic acid; The preparation method of the microbial fertilizer base comprises: using fern pod extract residue, king oyster mushroom residue and corn straw as fermentation substrates in a weight ratio of 1:2 to 4:1, and fermenting with Bacillus subtilis B115 as a fermentation bacterium to obtain the microbial fertilizer base; the fern pod extract residue is a residue phase obtained after fern pod extract is extracted with water; the preservation number of the Bacillus subtilis B115 is CGMCC NO.1210.

2. The tobacco fertilizer composition according to claim 1, characterized in that The water-soluble fertilizer for topdressing comprises, by weight, 400 parts of water extract of oriole, 100 parts of potassium nitrate, 100 parts of urea, 160 parts of calcium nitrate, 40 parts of sodium alginate, 20 parts of water-soluble starch, and 30 parts of polyglutamic acid.

3. The tobacco fertilizer composition according to claim 1, characterized in that When preparing the microbial fertilizer base fertilizer, the preparation method of the water extract residue of the pod fern is: wash the pod fern, chop it, add it to water 5 times the weight of the pod fern, extract it at 80°C for 4 hours, and filter the filtrate; add the filter residue to water 3 times the weight of the filter residue, extract it at 80°C for 4 hours, and filter the residue phase.

4. The tobacco fertilizer composition according to claim 3, characterized in that When preparing the microbial fertilizer base, the weight ratio of the fern water extract residue, the king oyster mushroom residue and the corn straw is 1:3:

1.

5. The tobacco fertilizer composition according to claim 1 or 4, characterized in that When preparing the microbial fertilizer base, when inoculating the Bacillus subtilis B115, the inoculation amount is 5%.

6. The tobacco fertilizer composition according to claim 5, characterized in that When preparing the microbial fertilizer base, the fermentation starting temperature is 30° C. and the fermentation time is 72 hours.

7. Use of a tobacco fertilizer composition for resisting disease and increasing yield under cadmium stress in tobacco cultivation.

8. The use according to claim 7, characterized in that During application, when applying the microbial fertilizer as base fertilizer, 80 g is applied to each tobacco plant as base fertilizer; when applying the water-soluble fertilizer as topdressing fertilizer, 200 mL is sprayed to each tobacco plant as topdressing.

9. The use according to claim 8, characterized in that When applying, after applying the microbial fertilizer as base fertilizer, spray the water-soluble fertilizer as topdressing on the seventh day.

10. The use according to claim 9, characterized in that When applying, after the first spraying of the water-soluble fertilizer as a topdressing, spray once every 10 days.

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