Crop rotation method for reducing morbidity of root-knot nematodes

Abstract

The invention provides a rotation method for reducing morbidity of root-knot nematodes, which comprises the following steps: planting waltheria indica: preparing soil, sowing waltheria indica in the middle of a furrow bed, covering soil, and spraying water until the furrow bed is infiltrated until the waltheria indica is harvested; one month before the tobacco seedlings are transplanted, the harvested waltheria indica is used as waltheria indica fertilizer, deep ploughing is carried out, the tobacco seedlings are transplanted, topping is carried out, leaves are reserved, and tobacco leaves are harvested. The waltheria indica and the tobacco are subjected to crop rotation, the waltheria indica fertilizer prepared from the waltheria indica, the edible mushroom residues and the black fungus fermentation liquor is applied in combination with planting of the waltheria indica, the two modes cooperate with each other, the soil microbial community structure is adjusted, the soil organic matter content is improved, the good prevention and control effect on the root-knot nematode is achieved, and the prevention and control effect can reach 88%; the harvested tobacco leaves are light in membrane lipid peroxidation degree, growth and development of tobacco plants are promoted, accumulation of substances contained in the tobacco leaves is improved, and the quality of the tobacco leaves is good.

Description

Technical Field

[0001] The invention relates to the technical field of crop planting, and in particular to a crop rotation method for reducing the incidence of root-knot nematodes. Background Art

[0002] Meloidogyne is a highly specialized omnivorous plant pathogenic nematode, which is mainly distributed in the deep soil layer of the arable layer. It has the characteristics of great destructive power, wide occurrence range, and great difficulty in prevention and control. Tobacco is one of the crops with extremely high economic value in my country, and accounts for a large proportion of the income of farmers in tobacco-growing areas. In recent years, the area of ​​tobacco cultivation has been reduced due to the influence of other crops, and the phenomenon of continuous cropping of tobacco is more serious, resulting in the high incidence of root-knot nematode diseases year by year. It causes a series of continuous cropping obstacles, resulting in high economic losses for tobacco, and the quality of tobacco leaves is also adversely affected. In the early stage of prevention and control of root-knot nematodes, thiazolyl, avermectin, thiamethoxam, etc. were mainly used, which easily made root-knot nematodes resistant to drugs and had certain toxicity, and their application in the field was limited. At present, more scholars tend to develop green anti-nematode agents for root-knot nematodes, but have not considered the problem of continuous cropping of tobacco. Summary of the invention

[0003] In view of this, the object of the present invention is to propose a crop rotation method for reducing the incidence of root-knot nematodes, by rotating snakewort and tobacco, combining snakewort fertilizer prepared by snakewort harvested from the crop rotation, edible mushroom residues and black fungus fermentation liquid, the two methods cooperate with each other, regulate the soil microbial community structure, improve the soil organic matter content and other characteristics, have a good prevention and control effect on root-knot nematodes, and have a better solution to the problem of continuous cropping of tobacco, the harvested tobacco leaves have a lighter degree of membrane lipid peroxidation, which is helpful to promote the growth and development of tobacco plants, and improve the accumulation of substances contained in tobacco leaves, and the tobacco leaves have good quality.

[0004] The technical solution of the present invention is achieved in this way:

[0005] A crop rotation method for reducing the incidence of root-knot nematodes comprises the following steps:

[0006] S1 Planting snakewort: prepare the land, sow snakewort in the middle of the bed, cover with soil, spread snakewort fertilizer, spray water to soak the bed, and harvest the snakewort;

[0007] S2 Planting tobacco: One month before transplanting tobacco seedlings, use the harvested snakehead as snakehead fertilizer, deep ploughing, transplanting tobacco seedlings, top cutting and leaving leaves, and harvesting tobacco leaves; the snakehead fertilizer includes snakehead, edible mushroom residue and black fungus fermentation liquid.

[0008] A further solution is that, by weight, the snakewort fertilizer includes 30-40 parts of snakewort, 20-35 parts of edible mushroom residues and 6-10 parts of black fungus fermentation liquid, and the usage amount is 600-750kg / mu.

[0009] A further solution is that in step S2, after transplanting the tobacco seedlings, the step also includes spraying black fungus fermentation liquid.

[0010] A further solution is that the spraying amount of black fungus fermentation liquid is 400-600 mL / m 2 , dilute the black fungus fermentation liquid 200 to 300 times before spraying.

[0011] A further solution is that the method for preparing the black fungus fermentation liquid is as follows: inoculate the black fungus strain into a PDA medium, culture at 24-26° C. for 1-1.5 days, add a liquid fermentation medium, and culture at 24-26° C. and 200-250 r / min for 5-6 days to obtain the black fungus fermentation liquid;

[0012] The liquid fermentation medium comprises glucose, potassium dihydrogen phosphate, tyrosinase powder, copper sulfate and magnesium sulfate.

[0013] In a further embodiment, each 1L of the liquid fermentation medium comprises 180-220g of glucose, 0.1-0.2g of potassium dihydrogen phosphate, 0.8-1.2g of tyrosinase powder, 0.3-0.5g of copper sulfate and 0.3-0.5g of magnesium sulfate.

[0014] A further solution is that the edible mushroom is at least one of Tremella fuciformis, Auricularia auricula, Pleurotus ostreatus, and Flammulina velutipes.

[0015] A further plan is to apply top dressing after transplanting the tobacco seedlings, with the ratio of nitrogen fertilizer, phosphorus fertilizer and potassium fertilizer in the fertilizer being 0.8-1:1-1.5:1-2.

[0016] A further plan is to apply topdressing 1 to 2 times within 15 to 25 days and 35 to 50 days after transplanting the tobacco seedlings.

[0017] A further solution is to apply 300-400 kg / hm2 2 .

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The invention rotates snakeweed and tobacco, combines snakeweed harvested from the rotation, edible mushroom residues and black fungus fermentation liquid to prepare snakeweed fertilizer, and the two methods cooperate with each other, help to regulate the soil microbial community structure, improve soil organic matter content and other properties, have a good control effect on root-knot nematodes, and the control effect can reach 88%.

[0020] The invention rotates coleus and tobacco, combines coleus harvested from the rotation, edible mushroom residues and black fungus fermentation liquid to prepare coleus fertilizer, and the harvested tobacco leaves have a lower lipid peroxidation degree, is helpful to promote the growth and development of tobacco plants, and improves the accumulation of substances contained in tobacco leaves, so that the tobacco leaves have good quality. DETAILED DESCRIPTION

[0021] In order to better understand the technical content of the present invention, specific embodiments are provided below to further illustrate the present invention.

[0022] Unless otherwise specified, the experimental methods used in the embodiments of the present invention are all conventional methods.

[0023] Unless otherwise specified, the materials, reagents, etc. used in the embodiments of the present invention can be obtained from commercial sources.

[0024] The mushroom residue used in the present invention is tremella residue and auricularia auricula residue in a mass ratio of 1:1, and the black auricularia auricula strain is purchased from the Institute of Microbiology of Heilongjiang Academy of Sciences, and the strain is Heiwei 15.

[0025] Example 1

[0026] Experimental design

[0027] The experiment was conducted in the tobacco experimental field in Danzhou City, Hainan Province from 2021 to 2022. The soil pH was 5.57, the organic matter content was 30.58g / kg, the available potassium content was 90.22mg / kg, the available phosphorus content was 46.50mgkg, and the available nitrogen content was 107.30mg / kg. The tobacco seedlings were grown by floating seedling cultivation. After disinfection and land preparation, deep plowing was carried out, and the tobacco seedlings were transplanted. The tops were removed about 45 days after transplanting, leaving 18 to 20 leaves, and the tobacco leaves were harvested. The total amount of nitrogen fertilizer applied was 300kg / hm 2 (The usage ratio of nitrogen, phosphorus and potassium is 1:1.2:2), which is applied once within 20 days and 40 days after transplanting tobacco seedlings; after disinfection and land preparation, take snakewort and sow it in the middle of the bed. After covering with soil, spray water to soak the bed until the snakewort is harvested.

[0028] The preparation method of black fungus fermentation liquid is as follows: black fungus strains with a diameter of about 5 mm are selected and inoculated into PDA culture medium, cultured at 24-26° C. for 1 day, and then liquid fermentation medium is added, and cultured at 24-26° C. and 250 r / min for 6 days to obtain black fungus fermentation liquid.

[0029] The components of the liquid fermentation medium are: 200 g / L glucose, 0.2 g / L potassium dihydrogen phosphate, 1.0 g / L tyrosinase powder, 0.4 g / L copper sulfate and 0.4 g / L magnesium sulfate.

[0030] The experiment set up 6 treatments according to the cultivation method and fertilizer management, each treatment was about 30m 2The planting areas are as follows:

[0031] (1) Continuous tobacco cropping;

[0032] (2) Codling-tobacco rotation: One month before transplanting tobacco seedlings, add harvested codling as codling fertilizer to deep plow the land. The codling fertilizer is 400 kg of codling and 500 kg of air-dried cow dung per mu.

[0033] (3) Tobacco continuous cropping - snake fruit fertilizer: One month before the second round of tobacco transplanting, add snake fruit fertilizer to deep plow and prepare the land. The snake fruit fertilizer is 350 kg of purchased snake fruit, 250 kg of edible mushroom residue and 80 kg of black fungus fermentation liquid per mu;

[0034] (4) Snakewort-tobacco rotation-snakewort fertilizer: One month before transplanting tobacco, add harvested snakewort as snakewort fertilizer to deep plow and prepare the land. The snakewort fertilizer is 350 kg of snakewort, 250 kg of edible mushroom residue and 80 kg of black fungus fermentation liquid per mu;

[0035] (5) Snakewort-tobacco rotation-snakewort fertilizer-fermentation liquid: One month before transplanting tobacco, add harvested snakewort as snakewort fertilizer to deep plowing and land preparation. Snakewort fertilizer is applied at a rate of 350 kg of snakewort, 250 kg of edible mushroom residue and 80 kg of black fungus fermentation liquid per mu. After transplanting tobacco seedlings, dilute the black fungus fermentation liquid 200 times before use, and spray at a rate of 500 mL / m 2 , sprayed 5 times in total;

[0036] (6) Continuous tobacco cropping: clean water control.

[0037] Example 2

[0038] According to GB / T 23222-2008 tobacco pest classification and investigation method, the incidence of root-knot nematode disease in different treatment groups was investigated. The formula is as follows:

[0039]

[0040] Table 1 Disease index and control effect of root-knot nematodes in each treatment group

[0041] Treatment Group T1 T2 T3 T4 T5 Disease index 62.38 45.86 26.44 12.53 11.23 Control effect / % 37.62 54.14 73.56 87.47 88.77

[0042] As shown in Table 1 above, the tobacco plants in each treatment group were infected with root-knot nematodes to varying degrees, and the control effects were from high to low in the order of T5 treatment group, T4 treatment group, T3 treatment group, T2 treatment group, and T8 treatment group. Among them, the control effect of T5 treatment group reached 88.77%; from the disease index, different treatment groups had a certain resistance to root-knot nematodes, among which the disease index of T4-T5 treatment groups was lower, indicating that the two treatments of T4-T5 made the tobacco plants have better resistance to root-knot nematodes, and the rotation of snakewort and tobacco, combined with the snakewort fertilizer prepared from the snakewort harvested in the rotation, edible mushroom residue and black fungus fermentation liquid, the two methods synergized with each other, adjusted the soil microbial community structure, improved the soil organic matter content and other characteristics, and had a good control effect on root-knot nematodes.

[0043] Example 3

[0044] The malondialdehyde (MDA) content was determined using a kit (Shanghai Youxuan Biotechnology Co., Ltd.), and the 10th to 12th tobacco leaves from the bottom to the top of the tobacco strain were selected for determination. The results are as follows.

[0045] Table 2 MDA content in each treatment group

[0046]

[0047]

[0048] As can be seen from Table 2 above, the MDA content in the T1 group was the highest, and the MDA content in the tobacco leaves of the T2, T4, and T5 groups remained at a relatively low level, indicating that the degree of membrane lipid peroxidation in the tobacco leaves of the T2, T4, and T5 groups was relatively light, which was helpful in promoting the growth and development of tobacco plants and increasing the accumulation of substances contained in the tobacco leaves.

[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A crop rotation method for reducing the incidence of root-knot nematodes, characterized in that: The steps include: S1 Planting snakewort: prepare the land, sow snakewort in the middle of the bed, cover with soil, spray water to soak the bed, and harvest the snakewort; S2 Planting tobacco: One month before transplanting tobacco seedlings, use the harvested snakehead as snakehead fertilizer, deep ploughing, transplanting tobacco seedlings, top cutting and leaving leaves, and harvesting tobacco leaves; the snakehead fertilizer includes snakehead, edible mushroom residue and black fungus fermentation liquid.

2. A crop rotation method for reducing the incidence of root-knot nematodes according to claim 1, characterized in that: Calculated by weight, the snakewort fertilizer comprises 30-40 parts of snakewort, 20-35 parts of edible mushroom residues and 6-10 parts of black fungus fermentation liquid, and the usage amount is 600-750kg / mu.

3. A crop rotation method for reducing the incidence of root-knot nematodes according to claim 1, characterized in that: In step S2, after transplanting the tobacco seedlings, the process also includes spraying black fungus fermentation liquid.

4. A crop rotation method for reducing the incidence of root-knot nematodes according to claim 3, characterized in that: The spraying rate of black fungus fermentation liquid is 400~600mL / m 2 , dilute the black fungus fermentation liquid 200 to 300 times before spraying.

5. A crop rotation method for reducing the incidence of root-knot nematodes according to any one of claims 1 to 4, characterized in that: The preparation method of the black fungus fermentation liquid comprises: taking black fungus strains and inoculating them into a PDA culture medium, culturing them at 24-26° C. for 1-1.5 days, adding a liquid fermentation culture medium, and culturing them at 24-26° C. and 200-250 r / min for 5-6 days to obtain the black fungus fermentation liquid; The liquid fermentation medium comprises glucose, potassium dihydrogen phosphate, tyrosinase powder, copper sulfate and magnesium sulfate.

6. A crop rotation method for reducing the incidence of root-knot nematodes according to claim 5, characterized in that: Each 1L of the liquid fermentation medium comprises 180-220g of glucose, 0.1-0.2g of potassium dihydrogen phosphate, 0.8-1.2g of tyrosinase powder, 0.3-0.5g of copper sulfate and 0.3-0.5g of magnesium sulfate.

7. A crop rotation method for reducing the incidence of root-knot nematodes according to claim 1 or 2, characterized in that: The edible mushroom is at least one of Tremella fuciformis, Auricularia auricula, Pleurotus ostreatus and Flammulina velutipes.

8. A crop rotation method for reducing the incidence of root-knot nematodes according to claim 1, characterized in that: After transplanting the tobacco seedlings, top dressing is also required. The ratio of nitrogen fertilizer, phosphorus fertilizer and potassium fertilizer in the fertilizer is 0.8~1:1~1.5:1~2.

9. A crop rotation method for reducing the incidence of root-knot nematodes according to claim 8, characterized in that: The timing for topdressing is 1 to 2 times within 15 to 25 days and 35 to 50 days after transplanting the tobacco seedlings.

10. A crop rotation method for reducing the incidence of root-knot nematodes according to claim 9, characterized in that: The application rate is 300~400kg / hm 2 .

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