A symbiotic breeding method of halodule and grouper

Abstract

The present application belongs to the technical field of aquaculture, and particularly relates to a symbiotic breeding method of sea grapes and grouper. In the process of symbiotic planting of the sea grapes and the grouper, the sea grapes absorb carbon dioxide and release oxygen through photosynthesis, and absorb harmful substances such as ammonia nitrogen, which helps to maintain a good water quality environment. At the same time, the algal bed formed by the sea grapes can not only provide hiding places for the grouper to reduce the stress response, but also indirectly provide natural bait for the grouper to promote its growth and development. The grouper will feed on part of the miscellaneous algae and other microorganisms to prevent excessive proliferation of other competitive algae and maintain the dominant position of the sea grapes. In addition, the activities of the grouper can agitate the bottom material to promote the decomposition of organic matter in the bottom mud. Therefore, the symbiotic breeding of the sea grapes and the grouper can not only improve the survival rate of the grouper, but also improve the yield and quality of the sea grapes.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of aquaculture, and particularly relates to a symbiotic breeding method of Caulerpa racemosa and Epinephelus. BACKGROUND

[0002] Epinephelus is a kind of popular edible and ornamental fish, belonging to Perciformes and Epinephelidae, and widely distributed in tropical and subtropical sea areas. Epinephelus not only has tender meat and delicious taste, but also has high nutritional value, such as rich in high-quality protein, unsaturated fatty acids, vitamins A, D and various minerals (such as calcium, phosphorus and iron), which is very beneficial to human health. Caulerpa racemosa, also known as "green caviar" or "sea elf", is a unique marine plant belonging to chlorophyta, caulerpaceae and caulerpa, which has very important significance in ecological and economic value.

[0003] In the prior art, Epinephelus and Caulerpa racemosa are often bred or planted separately. For example, by strictly controlling the breeding environment and feeding method of Epinephelus, the survival rate and growth rate of Epinephelus are improved in Chinese patent CN107455292A; by providing a device suitable for the growth of Caulerpa racemosa, the planting efficiency of Caulerpa racemosa is improved in Chinese patent CN218680920U. However, separate breeding of Epinephelus or separate planting of Caulerpa racemosa often causes waste of water body breeding environment resources. Therefore, how to provide a symbiotic breeding method of Caulerpa racemosa and Epinephelus not only improves the efficient use of the breeding environment, but also promotes the healthy and green development of the industries of Caulerpa racemosa and Epinephelus. SUMMARY

[0004] The purpose of the present application is to provide a symbiotic breeding method of Caulerpa racemosa and Epinephelus, which not only saves water resources, but also improves the survival rate of Epinephelus and the yield and quality of Caulerpa racemosa.

[0005] The present application provides a symbiotic breeding method of Caulerpa racemosa and Epinephelus, comprising the following steps:

[0006] Preparation of breeding substrate: mixing sand and soil and sterilizing at high temperature to obtain sterilized substrate; mixing the sterilized substrate with Rhodospirillum and air-drying to obtain breeding substrate;

[0007] Setting up a breeding tank: laying the breeding substrate and the attachment base in the sterilized breeding tank in turn, and injecting saltwater with a salinity of 2.3% to 2.6% and a height of >1.5m into the breeding tank for 2-3d, and then adjusting the height of the saltwater in the breeding tank to <1.4m to obtain a breeding tank for releasing seedlings;

[0008] The healthy sea grape seedlings are put into the breeding pool for 4-5 days, and then the grouper seedlings are put in for symbiotic breeding.

[0009] When the symbiotic breeding is carried out, the water environment parameters in the breeding pool include: temperature is 26-27℃, and dissolved oxygen is 6-8mg / L.

[0010] Preferably, the amount of the sea grape seedlings is 500-700 per square meter. 2 ;

[0011] The amount of the grouper seedlings is 75-100 per square meter. 2 .

[0012] Preferably, the mass ratio of the sand and the soil is 4-5:1.

[0013] The temperature of the high-temperature disinfection is 150-180℃, and the time of the high-temperature disinfection is 30-40min.

[0014] Preferably, the mass-volume ratio of the disinfected substrate and the Rhodospirillum is 30-50g:0.5-1mL.

[0015] The effective viable count of the Rhodospirillum is ≥0.5×10 6 cfu / mL.

[0016] Preferably, when the breeding substrate is laid, the thickness of the breeding substrate is 15-25cm.

[0017] Preferably, 7-10 days after the symbiotic breeding is carried out, the first fertilization is carried out in the breeding pool; the amount of the first fertilization includes: 30-35g / m 2 of seaweed residue, 5-8g / m 2 of sodium phosphate, 8-10g / m 2 of potassium chloride, and 10-20g / m 2 of soybean meal.

[0018] Preferably, 35-42 days after the symbiotic breeding is carried out, the second fertilization is carried out in the breeding pool; the amount of the second fertilization includes: 54-56g / m 2 of seaweed residue, 7-10g / m 2 of sodium phosphate, 12-15g / m 2 of potassium chloride, and 10-20g / m 2 of soybean meal.

[0019] Preferably, the step of disinfecting the breeding pool is that the breeding pool is disinfected by potassium permanganate.

[0020] Preferably, when the sea grape seedlings are cultured alone, the temperature of the water environment is 22-23℃, and the dissolved oxygen of the water environment is >6mg / L.

[0021] Preferably, the grouper is fed with small fish.

[0022] Beneficial effects:

[0023] The present application provides a symbiotic breeding method of sea grape and grouper, which uses sand, soil and Rhodopseudomonas to prepare a breeding substrate, which not only provides a good attachment base for sea grape, but also helps to exert the self-purification function of water quality; disinfecting the breeding pond helps to improve the stress resistance of sea grape and grouper; by culturing sea grape seedlings alone first, it is beneficial to the absorption of nutrients by sea grape in the early stage and improves its quality.

[0024] In the process of co-cultivation of sea grape and grouper, sea grape absorbs carbon dioxide and releases oxygen through photosynthesis, and also absorbs harmful substances such as ammonia nitrogen, which helps to maintain a good water quality environment; in addition, the algal bed formed by sea grape can provide a hiding place for grouper, reduce stress response and promote its growth and development; the rich algal resources attract small plankton to gather, forming a complete food chain and indirectly providing natural bait for grouper; at the same time, grouper will feed on some miscellaneous algae and other microorganisms, preventing the overgrowth of other competitive algae and maintaining the dominant position of sea grape; in addition, the activity of grouper can agitate the bottom material and promote the decomposition of organic matter in the bottom mud. Therefore, co-cultivation of sea grape and grouper not only improves the breeding efficiency, but also improves the water quality and reduces the incidence of diseases. DETAILED DESCRIPTION

[0025] In order to further illustrate the present application, the schemes provided by the present application are described in detail below in conjunction with examples, but they should not be understood as limiting the scope of protection of the present application.

[0026] Example 1

[0027] Experimental materials:

[0028] The variety of sea grape is Caulerpa lentillifera var.philippina;

[0029] The variety of grouper is Epinephelus akaara.

[0030] A symbiotic breeding method of sea grape and grouper, comprising the following steps:

[0031] (1) preparing the breeding substrate: mixing sand and crushed soil according to the mass ratio of 5:1, and then high-temperature sterilizing (the temperature of high-temperature sterilization is 180℃, and the time of high-temperature sterilization is 30min) to obtain the sterilized substrate; mixing the Rhodospirillum with the effective viable count of 0.5×10 6 cfu / mL with the sterilized substrate according to the volume-mass ratio of 1mL:50g, and then air-drying to obtain the breeding substrate;

[0032] (2) setting the breeding pond: selecting the cement breeding pond, and sterilizing the cement breeding pond by using potassium permanganate; after sterilization, laying the breeding substrate in step (1) and the plastic grid with the thickness of 20cm on the bottom of the breeding pond in turn, that is, completely covering the breeding substrate with the plastic grid as the attached substrate; then, injecting the salt water with the salinity of 2.5% and the height >1.5m into the breeding pond for 2-3d; then, adjusting the height of the salt water in the breeding pond to <1.4m to obtain the breeding pond for releasing the seedlings;

[0033] (3) releasing the seedlings: releasing the healthy sea grape seedlings into the breeding pond for releasing the seedlings in step (2) for separate culture, wherein the releasing amount of the sea grape seedlings is 500strains / m 2 ; by adding the water quality circulation system in the cement breeding pond, the temperature of the water body environment is maintained at 23℃, and the dissolved oxygen of the water body environment is >6mg / L during the separate culture;

[0034] After 5d of separate culture, the healthy grouper seedlings are released into the breeding pond for symbiotic breeding, wherein the releasing amount of the grouper seedlings is 100tails / m 2 ; during the symbiotic breeding, the water body environment temperature in the breeding pond is maintained at 27℃ by the water quality circulation system, and the dissolved oxygen is 7mg / L;

[0035] After 7d of symbiotic breeding, 30g / m 2 of seaweed residue, 8g / m 2 of sodium dihydrogen phosphate, 10g / m 2 of potassium chloride and 15g / m 2 of soybean meal are applied in the breeding pond; after 35d of symbiotic breeding, 55g / m 2 of seaweed residue, 10g / m 2 of sodium dihydrogen phosphate, 12g / m 2 of potassium chloride and 20g / m 2 of soybean meal are applied in the breeding pond; the grouper is fed with small miscellaneous fish twice a day, and the feeding rate is 3%-5% of the body weight of the grouper per day.

[0036] Example 2

[0037] Experimental materials:

[0038] The variety of sea grape is: Caulerpa lentillifera var. philippina;

[0039] The species of grouper is: Brown Spotted Grouper (Epinephelus fuscoguttatus).

[0040] A method for the symbiotic cultivation of sea grapes and grouper, comprising the following steps:

[0041] (1) Preparation of aquaculture substrate: Sand and crushed soil were mixed at a mass ratio of 5:1 and then sterilized at high temperature (180℃ for 30 minutes) to obtain the sterilized substrate; the effective viable bacteria count was 0.5×10 6 The cfu / mL Rhodospirillum was mixed with the sterilized substrate at a volume ratio of 1mL:50g and then dried to obtain the culture substrate.

[0042] (2) Setting up a breeding pond: Select a cement breeding pond and disinfect it with potassium permanganate. After disinfection, lay the breeding substrate and plastic mesh with a thickness of 20cm from step (1) on the bottom of the breeding pond, that is, use the plastic mesh as an attachment base to completely cover the breeding substrate; then inject salt water with a salinity of 2.3% and a height of >1.5m into the breeding pond and soak for 2-3 days; then adjust the height of the salt water in the breeding pond to <1.4m to obtain the breeding pond for stocking seedlings.

[0043] (3) Seedling introduction: Healthy sea grape seedlings are introduced into the culture pond described in step (2) for separate cultivation. The seedling introduction rate is 500 seedlings / m². 2 By adding a water circulation system to the cement aquaculture pond, the water temperature was maintained at 23℃ and the dissolved oxygen in the water environment was >6mg / L during individual cultivation.

[0044] After being cultured separately for 5 days, healthy grouper fry were released into the rearing pond for symbiotic farming, with a stocking density of 100 fry / m³. 2 During the aforementioned symbiotic farming, the water temperature in the aquaculture pond is maintained at 27°C and the dissolved oxygen at 7 mg / L through a water circulation system.

[0045] After 7 days of symbiotic cultivation, apply 30g / m³ of seaweed residue to the aquaculture pond. 2 Sodium dihydrogen phosphate 8g / m 2 Potassium chloride 10g / m 2 15g / m of soybean meal 2 ; During the 35-day period of symbiotic cultivation, apply 55g / m³ of seaweed residue to the aquaculture pond. 2 Sodium dihydrogen phosphate 10g / m2 , 12 g / m 2 and 20 g / m 2 ; the grouper is fed with small fish twice a day, and the feeding rate is 3%-5% of the body weight of the grouper per day.

[0046] Comparative Example 1

[0047] Experimental materials:

[0048] The variety of the green algae is Caulerpa lentillifera var. philippina.

[0049] The variety of the grouper is Epinephelus akaara.

[0050] A symbiotic breeding method of green algae and grouper, comprising the following steps:

[0051] (1) Preparing a breeding substrate: mixing sand and crushed soil at a mass ratio of 2:1, and then high-temperature sterilizing (the high-temperature sterilization temperature is 180°C, and the high-temperature sterilization time is 30 min) to obtain a sterilized substrate; mixing 1 mL of Rhodospirillum with an effective viable count of 0.5×10 6 cfu / mL with 50 g of the sterilized substrate at a volume-mass ratio of 1 mL:50 g, and then air-drying to obtain the breeding substrate;

[0052] (2) Setting up a breeding tank: selecting a cement breeding tank, and sterilizing the cement breeding tank by using potassium permanganate; after sterilization, laying the breeding substrate in step (1) and a plastic grid with a thickness of 20 cm on the bottom of the breeding tank in turn, i.e. completely covering the breeding substrate with the plastic grid as an attachment base; then, pouring saltwater with a salinity of 2.5% and a height >1.5 m into the breeding tank for 2-3 d; then, adjusting the height of the saltwater in the breeding tank to <1.4 m to obtain a breeding tank for releasing seedlings;

[0053] (3) Releasing seedlings: releasing healthy green algae seedlings into the breeding tank for releasing seedlings in step (2) for separate culture, wherein the releasing amount of the green algae seedlings is 500 plants / m 2 ; by adding a water quality circulation system in the cement breeding tank, the water body environment temperature is maintained at 23°C, and the dissolved oxygen is >6 mg / L during separate culture;

[0054] After 5 d of separate culture, releasing healthy grouper seedlings into the breeding tank for symbiotic breeding, wherein the releasing amount of the grouper seedlings is 100 tails / m 2 ; during the symbiotic breeding, the water body environment temperature in the breeding tank is maintained at 27°C by the water quality circulation system, and the dissolved oxygen is 7 mg / L;

[0055] After 7 days of symbiotic breeding, seaweed residue 30 g / m 2 , sodium dihydrogen phosphate 8 g / m 2 , potassium chloride 10 g / m 2 and soybean meal 15 g / m 2 ; 35 days of symbiotic breeding, seaweed residue 55 g / m 2 , sodium dihydrogen phosphate 10 g / m 2 , potassium chloride 12 g / m 2 and soybean meal 20 g / m 2 ; the grouper is fed with small miscellaneous fish twice a day, and the feeding rate is 3%-5% of the body weight of the grouper per day.

[0056] Comparative example 2

[0057] Experimental materials:

[0058] The variety of green seaweed is: Caulerpa lentillifera var. philippina;

[0059] The variety of grouper is: Epinephelus akaara.

[0060] A symbiotic breeding method of green seaweed and grouper, comprising the following steps:

[0061] (1) preparing the breeding substrate: mixing sand and crushed soil according to a mass ratio of 5:1, then high-temperature sterilizing (the high-temperature sterilization temperature is 180℃, and the high-temperature sterilization time is 30 min) to obtain the sterilized substrate; drying the sterilized substrate to obtain the breeding substrate;

[0062] (2) setting up the breeding pond: selecting a cement breeding pond, sterilizing the cement breeding pond with potassium permanganate, and then laying the breeding substrate in step (1) and the plastic grid with a thickness of 20 cm on the bottom of the breeding pond in turn, that is, the plastic grid is completely covered on the breeding substrate as the attachment base; then, injecting saltwater with a salinity of 2.5% and a height >1.5 m into the breeding pond for 2-3 days; then adjusting the height of the saltwater in the breeding pond <1.4 m to obtain the breeding pond for seedling planting;

[0063] (3) planting seedlings: planting healthy green seaweed seedlings into the breeding pond for seedling planting in step (2) for separate culture, wherein the planting amount of green seaweed seedlings is 500 plants / m 2 , and adding a water quality circulation system in the cement breeding pond to maintain the water body environment temperature at 23℃ and the dissolved oxygen >6 mg / L during separate culture;

[0064] After culturing for 5 days, the healthy grouper fry is put into the breeding pond for symbiotic breeding, wherein the amount of grouper fry put into the breeding pond is 100 per square meter 2 When the symbiotic breeding is carried out, the water body environment temperature in the breeding pond is maintained at 27°C and the dissolved oxygen is maintained at 7 mg / L by a water quality circulation system;

[0065] After 7 days of symbiotic breeding, 30 g / m 2 of seaweed residue, 8 g / m 2 of sodium dihydrogen phosphate, 10 g / m 2 of potassium chloride and 15 g / m 2 of soybean meal are applied in the breeding pond; after 35 days of symbiotic breeding, 55 g / m 2 of seaweed residue, 10 g / m 2 of sodium dihydrogen phosphate, 12 g / m 2 of potassium chloride and 20 g / m 2 of soybean meal are applied in the breeding pond; the grouper is fed with small miscellaneous fish twice a day, and the feeding rate is 3%-5% of the body weight of the grouper per day.

[0066] Comparative Example 3

[0067] Experimental materials:

[0068] The variety of green seaweed is Caulerpa lentillifera var. philippina;

[0069] The variety of grouper is Epinephelus akaara.

[0070] A symbiotic breeding method of green seaweed and grouper, comprising the following steps:

[0071] (1) preparing a breeding substrate: mixing sand and crushed soil according to a mass ratio of 5:1, and then high-temperature sterilizing (the high-temperature sterilization temperature is 180°C, and the high-temperature sterilization time is 30 min) to obtain a sterilized substrate; mixing Rhodospirillum with an effective viable count of 0.5×10 6 cfu / mL with the sterilized substrate according to a volume-mass ratio of 1 mL:50 g, and then air-drying to obtain the breeding substrate;

[0072] (2) setting a breeding pond: selecting a cement breeding pond, and sterilizing the cement breeding pond by using potassium permanganate; after sterilization, the breeding substrate in step (1) and a plastic grid with a thickness of 20 cm are laid on the bottom of the breeding pond in sequence, that is, the plastic grid is completely covered on the breeding substrate as an attachment base; then, salt water with a salinity of 2.1% and a height >1.5 m is injected into the breeding pond for 2-3 days; then, the height of the salt water in the breeding pond is adjusted to <1.4 m to obtain a breeding pond for putting seedlings;

[0073] (3) putting seedlings: putting healthy green seaweed seedlings into the breeding pool of step (2) for separate culture, wherein the amount of green seaweed seedlings is 500 plants / m 2 The water quality circulation system is added in the cement breeding pool to maintain the water body environment temperature at 23℃ and the dissolved oxygen at more than 6 mg / L during the separate culture;

[0074] After 5 days of separate culture, healthy grouper seedlings are put into the breeding pool for symbiotic breeding, wherein the amount of grouper seedlings is 100 tails / m 2 The water quality circulation system is used to maintain the water body environment temperature at 27℃ and the dissolved oxygen at 7 mg / L in the breeding pool during the symbiotic breeding;

[0075] After 7 days of symbiotic breeding, seaweed residue 30 g / m 2 , sodium dihydrogen phosphate 8 g / m 2 , potassium chloride 10 g / m 2 and soybean meal 15 g / m 2 are applied in the breeding pool; after 35 days of symbiotic breeding, seaweed residue 55 g / m 2 , sodium dihydrogen phosphate 10 g / m 2 , potassium chloride 12 g / m 2 and soybean meal 20 g / m 2 are applied in the breeding pool; the grouper is fed with small miscellaneous fish twice a day, and the feeding rate is 3%-5% of the body weight of the grouper per day.

[0076] Comparative Example 4

[0077] Experimental materials:

[0078] The variety of green seaweed is Caulerpa lentillifera var. philippina;

[0079] The variety of grouper is Epinephelus akaara.

[0080] A symbiotic breeding method of green seaweed and grouper, comprising the following steps:

[0081] (1) preparing breeding substrate: mixing sand and crushed soil at a mass ratio of 5:1, then high-temperature sterilizing (the high-temperature sterilization temperature is 180℃, and the high-temperature sterilization time is 30 min) to obtain sterilized substrate; mixing Rhodospirillum with an effective viable bacterial count of 0.5×10 6 cfu / mL with the sterilized substrate at a volume-mass ratio of 1 mL:50 g, and then air-drying to obtain the breeding substrate;

[0082] (2) setting up a culture pond: selecting a cement culture pond and disinfecting the cement culture pond by using potassium permanganate, after disinfection, laying the culture substrate in step (1) and the plastic grid with a thickness of 20 cm on the bottom of the culture pond in turn, that is, completely covering the culture substrate with the plastic grid as the attached base; then injecting brine with a salinity of 2.5% and a height of <1.4 m into the culture pond to obtain a culture pond for releasing seedlings;

[0083] (3) releasing seedlings: releasing healthy sea grape seedlings into the culture pond for releasing seedlings in step (2) for separate culture, wherein the release amount of sea grape seedlings is 500 plants / m 2 The water quality circulation system is added in the cement culture pond to maintain the water body environment temperature at 23℃ and the dissolved oxygen at >6 mg / L during separate culture;

[0084] After 5 days of separate culture, healthy grouper seedlings are released into the culture pond for symbiotic breeding, wherein the release amount of grouper seedlings is 100 tails / m 2 During the symbiotic breeding, the water quality circulation system is used to maintain the water body environment temperature at 27℃ and the dissolved oxygen at 7 mg / L in the culture pond;

[0085] After 7 days of symbiotic breeding, seaweed residue 30 g / m 2 , sodium dihydrogen phosphate 8 g / m 2 , potassium chloride 10 g / m 2 and soybean meal 15 g / m 2 are applied in the culture pond; after 35 days of symbiotic breeding, seaweed residue 55 g / m 2 , sodium dihydrogen phosphate 10 g / m 2 , potassium chloride 12 g / m 2 and soybean meal 20 g / m 2 are applied in the culture pond; the grouper is fed with small miscellaneous fish twice a day, and the daily feeding rate is 3%-5% of the body weight of the grouper.

[0086] Comparative Example 5

[0087] Experimental materials:

[0088] The variety of sea grape is: Caulerpa lentillifera var. philippina;

[0089] The variety of grouper is: Epinephelus akaara.

[0090] A symbiotic breeding method of sea grape and grouper, the steps are:

[0091] (1) preparing the breeding substrate: mixing the sand and the crushed soil according to the mass ratio of 5:1, and then high-temperature sterilizing (the temperature of high-temperature sterilization is 180℃, and the time of high-temperature sterilization is 30min) to obtain the sterilized substrate; mixing the Rhodospirillum with the effective viable count of 0.5×10 6 cfu / mL and the sterilized substrate according to the volume-mass ratio of 1mL:50g, and then air-drying to obtain the breeding substrate;

[0092] (2) setting the breeding tank: selecting the cement breeding tank, and sterilizing the cement breeding tank by using potassium permanganate; after sterilization, laying the breeding substrate in step (1) and the plastic grid with the thickness of 20cm on the bottom of the breeding tank in turn, that is, completely covering the breeding substrate with the plastic grid as the attached substrate; then, injecting the salt water with the salinity of 2.5% and the height >1.5m into the breeding tank for 2-3d; then, adjusting the height of the salt water in the breeding tank to <1.4m to obtain the breeding tank for releasing the seedlings;

[0093] (3) releasing the seedlings: releasing the healthy sea grape seedlings into the breeding tank for releasing the seedlings in step (2) for separate culture, wherein the releasing amount of the sea grape seedlings is 800 plants / m 2 ; by adding the water quality circulation system in the cement breeding tank, the temperature of the water body environment is maintained at 23℃, and the dissolved oxygen of the water body environment is maintained at 5mg / L during the separate culture;

[0094] After 5d of separate culture, the healthy grouper seedlings are released into the breeding tank for symbiotic breeding, wherein the releasing amount of the grouper seedlings is 100 tails / m 2 ; during the symbiotic breeding, the water body environment temperature in the breeding tank is maintained at 27℃ by the water quality circulation system, and the dissolved oxygen is maintained at 7mg / L;

[0095] After 7d of symbiotic breeding, 30g / m 2 of seaweed residue, 8g / m 2 of sodium dihydrogen phosphate, 10g / m 2 of potassium chloride and 15g / m 2 of soybean meal are applied in the breeding tank; after 35d of symbiotic breeding, 55g / m 2 of seaweed residue, 10g / m 2 of sodium dihydrogen phosphate, 12g / m 2 of potassium chloride and 20g / m 2 of soybean meal are applied in the breeding tank; the grouper is fed with small miscellaneous fish twice a day, and the feeding rate is 3%-5% of the body weight of the grouper per day.

[0096] Comparative Example 6

[0097] Experimental materials:

[0098] The species of green seaweed is Caulerpa lentillifera var. philippina;

[0099] The species of grouper is Epinephelus akaara.

[0100] A symbiotic breeding method of green seaweed and grouper, comprising the following steps:

[0101] (1) Preparing breeding substrate: mixing sand and crushed soil according to a mass ratio of 5:1, and then performing high-temperature sterilization (the temperature of high-temperature sterilization is 180℃, and the time of high-temperature sterilization is 30 min) to obtain sterilized substrate; mixing Rhodospirillum with an effective viable count of 0.5×10 6 cfu / mL with the sterilized substrate according to a volume-mass ratio of 1 mL:50 g, and then air-drying to obtain breeding substrate;

[0102] (2) Setting up a breeding tank: selecting a cement breeding tank, and sterilizing the cement breeding tank by using potassium permanganate; after sterilization, laying the breeding substrate in step (1) and plastic grid with a thickness of 20 cm on the bottom of the breeding tank in turn, that is, completely covering the breeding substrate with the plastic grid as an attachment base; then, pouring saltwater with a salinity of 2.5% and a height >1.5 m into the breeding tank for 2-3 days of soaking; then, adjusting the height of the saltwater in the breeding tank to <1.4 m to obtain a breeding tank for seedling release;

[0103] (3) Releasing seedlings: releasing healthy green seaweed seedlings into the breeding tank for seedling release in step (2) for separate culture, wherein the release amount of the green seaweed seedlings is 500 plants / m 2 ; by adding a water quality circulation system in the cement breeding tank, the temperature of the water body environment is maintained at 23℃, and the dissolved oxygen of the water body environment is >6 mg / L during separate culture;

[0104] After 5 days of separate culture, releasing healthy grouper seedlings into the breeding tank for symbiotic breeding, wherein the release amount of the grouper seedlings is 100 tails / m 2 ; during the symbiotic breeding, the water body environment temperature in the breeding tank is maintained at 25℃ by the water quality circulation system, and the dissolved oxygen is 5 mg / L;

[0105] After 7 days of symbiotic breeding, applying seaweed residue 30 g / m 2 , sodium dihydrogen phosphate 8 g / m 2 , potassium chloride 10 g / m 2 and soybean meal 15 g / m 2 in the breeding tank; after 35 days of symbiotic breeding, applying seaweed residue 55 g / m 2 , sodium dihydrogen phosphate 10 g / m 2, potassium chloride 12 g / m 2 and soybean meal 20 g / m 2 ; the grouper is fed with small miscellaneous fish twice a day, and the feeding rate is 3%-5% of the body weight of the grouper per day.

[0106] Comparative Example 7

[0107] Experimental materials:

[0108] The variety of the green algae is: Caulerpa lentillifera var. philippina;

[0109] The variety of the grouper is: Epinephelus akaara.

[0110] A symbiotic breeding method of green algae and grouper, comprising the following steps:

[0111] (1) Preparing a breeding substrate: mixing sand and crushed soil according to a mass ratio of 5:1, and then high-temperature sterilizing (the high-temperature sterilization temperature is 180℃, and the high-temperature sterilization time is 30 min) to obtain a sterilized substrate; mixing 1 mL of Rhodospirillum with an effective viable count of 0.5×10 6 cfu / mL with 50 g of the sterilized substrate according to a volume-mass ratio of 1 mL:50 g, and then air-drying to obtain the breeding substrate;

[0112] (2) Setting up a breeding tank: selecting a cement breeding tank, and sterilizing the cement breeding tank by using potassium permanganate; after sterilization, laying the breeding substrate in step (1) and a plastic grid with a thickness of 20 cm on the bottom of the breeding tank in turn, that is, completely covering the breeding substrate with the plastic grid as an attachment substrate; then, pouring saltwater with a salinity of 2.5% and a height >1.5 m into the breeding tank for 2-3 days of soaking; then, adjusting the height of the saltwater in the breeding tank to <1.4 m to obtain a breeding tank for releasing seedlings;

[0113] (3) Releasing seedlings: releasing healthy green algae seedlings into the breeding tank for releasing seedlings in step (2) for separate culture, wherein the release amount of the green algae seedlings is 500 plants / m 2 ; by adding a water quality circulation system in the cement breeding tank, the temperature of the water body environment during separate culture is maintained at 23℃, and the dissolved oxygen of the water body environment is >6 mg / L;

[0114] After 5 days of separate culture, releasing healthy grouper seedlings into the breeding tank for symbiotic breeding, wherein the release amount of the grouper seedlings is 100 tails / m 2 ; during the symbiotic breeding, the water body environment temperature in the breeding tank is maintained at 27℃ by the water quality circulation system, and the dissolved oxygen is 7 mg / L;

[0115] After 7 days of symbiotic breeding, seaweed residue 30 g / m 2 , sodium dihydrogen phosphate 8 g / m 2 , potassium chloride 10 g / m 2 and soybean meal 15 g / m 2 are applied in the breeding pond; the grouper is fed with small miscellaneous fish twice a day, and the daily feeding rate is 3%-5% of the body weight of the grouper.

[0116] Comparative example 8

[0117] Experimental materials:

[0118] The variety of the green seaweed is Caulerpa lentillifera var. philippina;

[0119] A method for planting green seaweed, comprising the following steps:

[0120] (1) Preparing a breeding substrate: mixing sand and crushed soil according to a mass ratio of 5:1, and then high-temperature sterilizing (the high-temperature sterilization temperature is 180℃, and the high-temperature sterilization time is 30 min) to obtain a sterilized substrate; mixing Rhodospirillum with an effective viable count of 0.5×10 6 cfu / mL with the sterilized substrate according to a volume-mass ratio of 1 mL:50 g, and then air-drying to obtain a breeding substrate;

[0121] (2) Setting up a breeding pond: selecting a cement breeding pond, and sterilizing the cement breeding pond by using potassium permanganate; after sterilization, laying the breeding substrate in step (1) and a plastic grid with a thickness of 20 cm on the bottom of the breeding pond in turn, i.e. completely covering the breeding substrate with the plastic grid as an attachment base; then, pouring saltwater with a salinity of 2.5% and a height >1.5 m into the breeding pond for 2-3 days; then, adjusting the height of the saltwater in the breeding pond to <1.4 m to obtain a breeding pond for planting seedlings;

[0122] (3) Planting seedlings: planting healthy green seaweed seedlings into the breeding pond for planting seedlings in step (2) for separate culture, wherein the planting amount of the green seaweed seedlings is 500 plants / m 2 ; by adding a water quality circulation system in the cement breeding pond, the temperature of the water body environment is maintained at 23℃, and the dissolved oxygen of the water body environment is >6 mg / L;

[0123] After 7 days of separate culture, seaweed residue 30 g / m 2 , sodium dihydrogen phosphate 8 g / m 2 , potassium chloride 10 g / m 2 and soybean meal 15 g / m 2 are applied in the breeding pond; after 35 days of symbiotic breeding, seaweed residue 55 g / m2 sodium phosphate 10 g / m 2 potassium chloride 12 g / m 2 and soybean meal 20 g / m 2 .

[0124] Comparative Example 9

[0125] Experimental materials:

[0126] The grouper species is: Epinephelus akaara.

[0127] A grouper breeding method, the steps are:

[0128] (1) Preparation of breeding substrate: mix sand and crushed soil according to a mass ratio of 5:1, then high-temperature sterilize (high-temperature sterilization temperature is 180℃, high-temperature sterilization time is 30 min) to obtain the sterilized substrate; mix 1 mL of Rhodospirillum with an effective viable count of 0.5×10 6 cfu / mL with 50 g of the sterilized substrate according to a volume-mass ratio of 1 mL:50 g, and air dry to obtain the breeding substrate;

[0129] (2) Set up the breeding pond: select a cement breeding pond, and sterilize the cement breeding pond with potassium permanganate; after sterilization, lay the breeding substrate in step (1) and the plastic grid with a thickness of 20 cm on the bottom of the breeding pond in turn, that is, the plastic grid is completely covered on the breeding substrate as an attached substrate; then, inject saltwater with a salinity of 2.5% and a height >1.5 m into the breeding pond for 2-3 d; then adjust the height of the saltwater in the breeding pond to <1.4 m to obtain the breeding pond for releasing fry;

[0130] (3) Release fry: release healthy grouper fry into the breeding pond for breeding, wherein the release amount of grouper fry is 100 tails / m 2 ; maintain the water body environmental temperature in the breeding pond at 27℃ and the dissolved oxygen at 7 mg / L through a water quality circulation system; feed the grouper with small miscellaneous fish twice a day, and the daily feeding rate is 3%-5% of the body weight of the grouper.

[0131] Application Example 1

[0132] The survival rate, yield and polysaccharide content of sea grapes in Examples 1-2 and Comparative Examples 1-8 are counted respectively, and the results are shown in Table 1.

[0133] Table 1 Production of sea grapes in different treatments

[0134]

[0135]

[0136] As can be seen from Table 1, compared with Comparative Examples 1-8, the survival rate of Gracilaria dura in Example 1-2 is high, and the yield is high, and the polysaccharide content is as high as 44.9%; while in Comparative Examples 1-8, the highest polysaccharide content is only 42.9%. In addition, as can be seen from Comparative Example 8, when Gracilaria dura is planted alone, not only the polysaccharide content is low, but also the survival rate is low. It can be seen that after symbiotic cultivation of Gracilaria dura and Epinephelus, the activity of Epinephelus not only helps to prevent the overgrowth of other competitive algae, but also promotes the decomposition of organic matter in the sediment, thereby improving the yield of Gracilaria dura.

[0137] Application Example 2

[0138] The survival rates of Epinephelus in Example 1-2, Comparative Example 1-7 and Comparative Example 9 after 3 weeks of cultivation were counted respectively, and the results are shown in Table 2.

[0139] Table 2 Survival rates of Epinephelus in different treatments

[0140] Treatment Survival (%) Example 1 99.2％ Example 2 99％ Comparative Example 1 98％ Comparative Example 2 98.7％ Comparative Example 3 94.3％ Comparative Example 4 95.4％ Comparative Example 5 91.7％ Comparative Example 6 96.8％ Comparative Example 7 94.6％ Comparative Example 9 90.5％

[0141] As can be seen from Table 2, compared with Comparative Examples 1-7 and Comparative Example 9, the survival rate of Epinephelus in Example 1-2 is as high as 99% or more, while the highest survival rate of Epinephelus in the comparative examples is only 98.7%; especially in Comparative Example 9, the survival rate of Epinephelus is only 90.5%. It can be seen that Gracilaria dura helps to maintain a good water quality environment; the algal bed formed by Gracilaria dura not only provides a hiding place for Epinephelus to reduce stress response, but also indirectly provides natural feed for Epinephelus to promote its growth and development.

[0142] In summary, in the process of symbiotic cultivation of Epinephelus and Gracilaria dura, Gracilaria dura absorbs carbon dioxide and releases oxygen through photosynthesis, and absorbs harmful substances such as ammonia nitrogen, which helps to maintain a good water quality environment; the algal bed formed by Gracilaria dura not only provides a hiding place for Epinephelus to reduce stress response, but also indirectly provides natural feed for Epinephelus to promote its growth and development; Epinephelus will feed on part of the miscellaneous algae and other microorganisms to prevent the overgrowth of other competitive algae and maintain the dominant position of Gracilaria dura; in addition, the activity of Epinephelus can agitate the bottom material to promote the decomposition of organic matter in the sediment. Therefore, the technical scheme provided by the present application symbiotic cultivation of Gracilaria dura and Epinephelus not only can improve the cultivation efficiency, but also can improve the water quality and reduce the disease incidence

[0143] Although the above examples have made a detailed description of the present application, it is only a part of the embodiments of the present application, not all the embodiments, and other embodiments can be obtained according to the present embodiments without creativity, which belong to the protection scope of the present application.

Claims

1. A method for symbiotic breeding of sea grapes and grouper, characterized by, The method comprises the following steps: Preparation of breeding substrate: after mixing sand and clay, high-temperature sterilization is performed to obtain sterilized substrate; Mixing the sterilized substrate with Rhodospirillum and air-drying to obtain breeding substrate; Setting up breeding pond: the breeding substrate and attachment base are sequentially laid in the sterilized breeding pond, and saltwater with salinity of 2.3%-2.6% and height >1.5m is injected into the breeding pond for 2-3d, and then the height of the saltwater in the breeding pond is adjusted to <1.4m to obtain breeding pond for seedling release; Release of seedlings: after healthy sea grape seedlings are released into the breeding pond for seedling release and cultured for 4-5d, grouper seedlings are released for symbiotic breeding; When the symbiotic breeding is performed, the water environmental parameters in the breeding pond include: temperature of 26-27℃, and dissolved oxygen of 6-8mg / L.

2. The symbiotic species breeding method according to claim 1, characterized by, The amount of the sea grape seedlings to be put is 500-700 seedlings / m 2 ; The quantity of the grouper fry to be released is 75-100 tails / m 2 .

3. The symbiotic species breeding method according to claim 1, characterized by, The mass ratio of the sand and clay is 4-5:1; The high-temperature sterilization is performed at a temperature of 150-180℃ for 30-40min.

4. The symbiotic species breeding method according to claim 1, characterized by, The mass-volume ratio of the sterilized substrate and Rhodospirillum is 30-50g:0.5-1mL. The effective viable cell number of the Rhodospirillum is ≥ 0.5 x 10 6 cfu / mL.

5. The symbiotic species breeding method according to claim 1, characterized by, When the breeding substrate is laid, the thickness of the breeding substrate is 15-25cm.

6. The symbiotic species breeding method according to claim 1, characterized by, After 7-10 days of the symbiotic breeding, the first fertilization is carried out in the breeding pool; the amount of the first fertilization includes: 30-35 g / m 2 of seaweed residue, 5-8 g / m 2 of sodium dihydrogen phosphate, 8-10 g / m 2 of potassium chloride and 10-20 g / m 2 of soybean meal.

7. The symbiotic species breeding method according to claim 1, characterized by, After 35-42 days of the symbiotic breeding, secondary fertilization is carried out in the breeding pond, and the amount of the secondary fertilization includes: 54-56 g / m 2 of seaweed residue, 7-10 g / m 2 of sodium dihydrogen phosphate, 12-15 g / m 2 of potassium chloride, and 10-20 g / m 2 of soybean meal.

8. The symbiotic species breeding method according to claim 1, characterized by, The breeding pond is sterilized by using potassium permanganate.

9. The symbiotic species breeding method according to claim 1, characterized by, When the sea grape seedlings are cultured alone, the temperature of the water environment is 22-23℃, and the dissolved oxygen of the water environment is >6mg / L.

10. The symbiotic species breeding method according to claim 1, characterized by, The grouper is fed with small fish.

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