A mixed culture method of Porphyra yezoensis and Ulva longissima

Abstract

The present invention proposes a mixed culture method of Porphyra yezoensis and Ulva feldspar. The present invention comprises: 1) Porphyra yezoensis is planted in late September, and conchospore seedlings of Porphyra yezoensis are collected on a culture net, and the net is hung in the sea; 2) Porphyra yezoensis culture management is performed by drying and washing the net according to the epiphytic conditions of miscellaneous algae; 3) Porphyra yezoensis is harvested and cultured for 50-60 days, and Porphyra yezoensis is harvested; 4) Ulva feldspar seedlings and planting are collected, Ulva feldspar seed vegetables are washed, ripened, released, filtered, and sprinkled with Ulva feldspar spore water, and the Ulva feldspar seed vegetables are put into a net bag and hung on the culture net for culture; 5) Ulva feldspar culture management continues to harvest Porphyra yezoensis, and all Porphyra yezoensis on the net are harvested; 6) Ulva feldspar is harvested and cultured for 70-80 days, and Ulva feldspar is harvested. The invention has simple operation and fewer steps, improves the breeding efficiency, realizes the mixed breeding of Porphyra yezoensis and Ulva longissima, makes full use of the breeding sea area and equipment, reduces the cost, and achieves the effect of increasing production and income.

Description

Technical Field

[0001] The invention relates to the technical field of seaweed cultivation, in particular to a mixed cultivation method of Porphyra yezoensis and Ulva longissima. Background Art

[0002] Porphyra yezoensis, Rhodophyceae, Rhodophyceae, bright purple or slightly blue-green, oval or oblong, generally 12-70cm high. The base is round or heart-shaped, with wrinkles on the edge, and the cells are neatly arranged, smooth and without serrations; the chromatophores are star-shaped, located in the center, and the base cells extend into an oval or long rod shape; it is monoecious, and the thallus can form a single spore for vegetative reproduction. It is a common species along the northern coast of China and the main cultivated algae north of the Yangtze River. It tastes delicious, rich in amino acids and trace elements, and is an economic seaweed with high edible value, medicinal value and industrial value. The fresh price is 6-10 yuan / kg. The national porphyra cultivation area reaches 72,000 hectares, accounting for half of the national algae cultivation area.

[0003] Ulva linza, a member of the Ulva family, is a common large green algae along the coast of my country. It grows on reefs in the mid- and low-tidal zones or gravels on the inner bay beaches. It has a long growth period and reproduces all year round. March to June is its best growth period, and October to December is its secondary growth period. Ulva linza can lower cholesterol. Its protein content is 27%, and its fat content is only 0.9%. Its magnesium, iron, and zinc content are also higher than other seaweeds such as kelp and laver. It is a low-fat, high-protein, and rich in vitamins and minerals seaweed food. In addition, it can also inhibit the growth of red tide algae, and has great potential in the prevention and control of red tides. It has high nutritional value, medicinal value, and ecological value.

[0004] The cultivation period of Porphyra yezoensis is generally between September and February of the following year, and the first crop of Porphyra yezoensis is harvested around November. Harvesting is usually done by harvesting boats, and the pulling force of the rotating blades will cause many Porphyra yezoensis to be uprooted, making the density thinner in the later stage of growth and causing a large number of algae to reproduce. After the first three crops of Porphyra yezoensis are harvested, its yield and quality often drop sharply, and the price also decreases. Therefore, starting from February, the cultivation sea areas and equipment of Porphyra yezoensis have been idle one after another, resulting in a huge waste of resources. This method of cultivating single Porphyra yezoensis often has the problems of low efficiency, low risk resistance, and large fluctuations in benefits, which is not conducive to the stable and sustainable development of the Porphyra yezoensis cultivation industry. Summary of the invention

[0005] The present invention aims to provide a mixed culture method of Porphyra yezoensis and Ulva longissima, aiming to solve the problems of low culture efficiency, weak continuity, serious waste of resources and low risk resistance in the existing culture method of single Porphyra yezoensis, thus resulting in low culture benefits.

[0006] In order to solve the above technical problems, the technical solution of the present invention is achieved as follows:

[0007] The mixed cultivation method of Porphyra yezoensis and Ulva longissima of the present invention comprises the following steps:

[0008] 1) Porphyra yezoensis cultivation

[0009] In late September, when the water temperature in the aquaculture area is 19-21℃, collect the conchospore seedlings of Porphyra yezoensis onto the aquaculture net and hang the net in the sea;

[0010] 2) Management of Porphyra yezoensis cultivation

[0011] During the breeding process, the nets are dried and washed according to the algae growth. The nets are dried 3-5 days after being put into the sea. They are dried frequently during the germination period. After the germination period, the interval and time of drying the nets are gradually extended. When there are a lot of algae and floating mud, the nets are washed and the frequency of drying the nets is increased.

[0012] 3) Harvesting Porphyra yezoensis

[0013] After 50-60 days of cultivation, the harvest of Porphyra yezoensis begins in mid-November, with one crop harvested every 15-20 days. From mid-November to the end of December, 3-4 crops of Porphyra yezoensis are harvested.

[0014] 4) Collecting and planting Ulva longituba seedlings

[0015] At the end of December, well-grown adults of Ulva femoris were collected and selected as seed vegetables, washed, ripened in a temporary culture pond, and released spores in a release pond; taken out, filtered with a 60-120 mesh filter, spore water after filtration was collected, and the Ulva femoris spore water was sprinkled on the sea surface where Porphyra yezoensis was cultured; at the same time, the Ulva femoris seed vegetables obtained during the filtration process were collected, put into a net bag, and hung on a culture net for culture;

[0016] 5) Ulva longituba cultivation and management

[0017] The seawater temperature is low from January to February. During this period, the young spores of Ulva feldspar on the culture net grow slowly, which does not affect the harvesting of Porphyra yezoensis. Porphyra yezoensis grows normally and is harvested for 3-4 batches. During the last harvest, the position of the harvesting blade is adjusted to harvest all the Porphyra yezoensis on the net to provide space for the growth of Ulva feldspar. From March to June, Ulva feldspar enters a rapid growth period, and the nets are washed, dried and fertilized;

[0018] 6) Harvesting Ulva longituba

[0019] After 70-80 days of cultivation, the harvest of Ulva longituba begins in mid-March, with one crop harvested every 10-15 days. From mid-March to mid-June, 6-8 crops of Ulva longituba are harvested.

[0020] The present invention realizes the mixed cultivation of Porphyra yezoensis and Ulva longissima in one cultivation sea area and one set of cultivation equipment, so that the cultivation sea area and the cultivation equipment are fully utilized, the cultivation sea area and the cultivation equipment are avoided to be idle in winter and spring, and the cultivation period is extended; the cultivation method is simple to operate, easy to master, convenient to implement, low in technical level requirements, saves manpower and material resources, has high cultivation efficiency, and fully utilizes resources, and realizes the increased production cultivation of Porphyra yezoensis and the artificial cultivation of Ulva longissima, achieving the increased production and increased income cultivation of seaweed, and improving the risk resistance of the seaweed cultivation industry.

[0021] As a preferred embodiment, in the step 2), the net is dried once every 2 days for 2-3 hours during the seedling emergence period, and once every 3-5 days for 3-4 hours after the seedling emergence period. In the present invention, during the cultivation process of Porphyra yezoensis, the net is dried according to the epiphytic conditions of the weeds to fully remove the weeds and ensure the healthy growth of Porphyra yezoensis.

[0022] As a preferred embodiment, in step 3), 5-7 cm of remaining algae are retained after each harvest; in step 5), the length of remaining algae after the last harvest does not exceed 1 cm; in step 6), 10-12 cm of remaining algae are retained after each harvest, and all are harvested at the last harvest. In the present invention, Porphyra yezoensis can be harvested 6-8 times in total, and the length of remaining algae after harvesting is relatively long to ensure its subsequent continued growth; after planting Ulva longissima, Porphyra yezoensis can still grow and harvest normally, and continue to harvest 3-4 times, and all of Porphyra yezoensis is harvested at the last harvest; Ulva longissima can be harvested 6-8 times, and the length of remaining algae after each harvest is relatively long to ensure subsequent continued growth, and all are harvested at the last harvest; the length of remaining algae after harvesting is controlled to avoid excessive harvesting that affects the continued growth of the remaining algae, and to avoid improper harvesting that affects the growth rate of the remaining algae.

[0023] As a preferred embodiment, in the step 4), the color of the spore water in the release pool becomes dark green, and the release is stopped when the number of downstream spores reaches 200-300 per visual field under a microscope of 100 times. The present invention determines whether the release is completed by observing the color and the number of downstream spores under the microscope. This method is accurate in judgment, realizes the control of the release of the spores, and improves the utilization rate of the vegetable growing of Ulva longituba.

[0024] As a preferred embodiment, in the step 4), the net bag for hanging and growing Ulva longituba is made of a 60-100 mesh nylon filter net, with a length of 30-40 cm and a width of 20-30 cm, and each net bag contains 300-400 g of Ulva longituba vegetables. The breeding equipment of the present invention includes a breeding raft frame and a breeding net, and the breeding raft frame includes two floating rods arranged in parallel, the arrangement direction of the floating rods is the same as the tidal direction, the two floating rods are connected by cables, and the two ends of the floating rods are horizontally fixed on the foundation piles by pile cables; a buoy is provided on the floating rod, and the breeding net is arranged between the two floating rods, and the two sides of the breeding net are also fixed on the cables by fixed ropes; a breeding net is provided on a breeding raft frame, and adjacent breeding raft frames are connected together. In the present invention, Porphyra yezoensis is planted on the breeding net, Ulva longituba spore water is sprinkled on the breeding net, and the net bag containing Ulva longituba vegetables is hung on the breeding net, the fixed rope and the cable.

[0025] As a preferred embodiment, in the step 4), the collected spore water of Ulva feldspar is sprayed within 24 hours, and is diluted 5-6 times with seawater before spraying, and the spore water is fully stirred. The spore water of Ulva feldspar of the present invention has good uniformity, and the mobile spores do not settle or adhere during spraying, thereby achieving uniform spraying of the spore water of Ulva feldspar.

[0026] As a preferred embodiment, in the step 4), the ripening is accelerated by aeration in the temporary culture pond, and the culture conditions are: light intensity 5000-6000lx, light cycle 10L:14D, culture water temperature 10-14°C, and temporary culture time 3-5 days; the release pond is provided with sand-filtered seawater at 7-10°C, and under stirring and aeration, a light intensity of 7000-8000lx is used for irradiation for 0.5-1 hour. The growth period of Ulva longissima is long, and it reproduces all year round. The present invention adopts low temperature, water flow and light stimulation in the release of Ulva longissima spores, which can make Ulva longissima release a large number of spores in a short time; this method does not require high maturity of Ulva longissima, and the Ulva longissima after release can still be reused. By hanging Ulva longissima vegetables at sea, supplementary seedling collection is achieved, the efficiency of Ulva longissima seedling collection is improved, and the utilization rate of Ulva longissima vegetables is improved.

[0027] As a preferred embodiment, in the step 4), before spraying the spore water of Ulva feldspar and hanging the Ulva feldspar to grow vegetables, the breeding net is washed and dried. In the present invention, before spraying the spore water of Ulva feldspar and hanging the Ulva feldspar to grow vegetables, there is no need to specially clean the breeding net, and only washing and drying the breeding net is required, which is easy to operate and easy to implement.

[0028] As a preferred embodiment, in the step 4), the spraying of the spore water of Ulva feldspar is carried out at low tide. Spraying the spores of Ulva feldspar at low tide can fully ensure the uniformity of the spraying of the spores of Ulva feldspar. The cultivated Ulva feldspar in the present invention has bright green color and good quality.

[0029] As a preferred embodiment, in the step 5), fertilization is carried out by spraying, the nitrogen fertilizer is a nitrogen fertilizer seawater solution with a nitrogen concentration of 18-20 mg / L prepared by ammonium bicarbonate or urea, and the phosphate fertilizer is a phosphate fertilizer seawater solution with a phosphorus concentration of 3-5 mg / L prepared by potassium dihydrogen phosphate. In the present invention, the nitrogen fertilizer is a nitrogen fertilizer seawater solution with a nitrogen concentration of 18-20 mg / L prepared by ammonium bicarbonate (NH4HCO3) or urea, and the phosphate fertilizer is a phosphate fertilizer seawater solution with a phosphorus concentration of 3-5 mg / L prepared by potassium dihydrogen phosphate (KH2PO4); the present invention also successfully realizes the artificial cultivation of Ulva feldspar, realizes the increase of production and income of Ulva feldspar, and improves the economic benefits of seaweed cultivation.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention realizes the mixed cultivation of Porphyra yezoensis and Ulva longissima in one cultivation sea area and one set of cultivation equipment, so that the cultivation sea area and the cultivation equipment are fully utilized, avoiding the idleness of the cultivation sea area and the cultivation equipment in winter and spring, and extending the cultivation period; the cultivation method is simple to operate, easy to master, convenient to implement, has low technical requirements, saves manpower and material resources, has high cultivation efficiency, and fully utilizes resources, which not only realizes the increased production cultivation of Porphyra yezoensis, but also realizes the artificial cultivation of Ulva longissima, achieves the increased production and increased income cultivation of seaweed, and improves the risk resistance of the seaweed cultivation industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic plan view of the structure of one embodiment of the aquaculture equipment in the mixed aquaculture method of Porphyra yezoensis and Ulva longissima proposed by the present invention;

[0032] Figure 2 for Figure 1 A magnified schematic diagram of the structure of the culture raft;

[0033] In the figure: 1-foundation pile; 2-pile cable; 3-breeding raft frame; 4-buoy; 5-breeding net; 6-fixing rope;

[0034] 31- floating rod; 32- cable. DETAILED DESCRIPTION

[0035] The technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] The mixed cultivation method of Porphyra yezoensis and Ulva longissima of the present invention comprises the following steps:

[0037] 1) Porphyra yezoensis cultivation

[0038] In late September, when the water temperature in the aquaculture area is 19-21℃, collect the conchospore seedlings of Porphyra yezoensis onto the aquaculture net and hang the net in the sea;

[0039] 2) Management of Porphyra yezoensis cultivation

[0040] During the breeding process, the nets are dried and washed according to the algae growth. The nets are dried 3-5 days after being put into the sea. They are dried frequently during the germination period. After the germination period, the interval and time of drying the nets are gradually extended. When there are a lot of algae and floating mud, the nets are washed and the frequency of drying the nets is appropriately increased.

[0041] 3) Harvesting Porphyra yezoensis

[0042] After 50-60 days of cultivation, the harvest of Porphyra yezoensis begins in mid-November, with one crop harvested every 15-20 days. From mid-November to the end of December, 3-4 crops of Porphyra yezoensis are harvested.

[0043] 4) Collecting and planting Ulva longituba seedlings

[0044] At the end of December, well-grown adults of Ulva femoris were collected and selected as seed vegetables, washed, ripened in a temporary culture pond, and released spores in a release pond; taken out, filtered with a 60-120 mesh filter, spore water after filtration was collected, and the Ulva femoris spore water was sprinkled on the sea surface where Porphyra yezoensis was cultured; at the same time, the Ulva femoris seed vegetables obtained during the filtration process were collected, put into a net bag, and hung on a culture net for culture;

[0045] 5) Ulva longituba cultivation and management

[0046] The seawater temperature is low from January to February. During this period, the young spores of Ulva feldspar on the culture net grow slowly, which does not affect the harvesting of Porphyra yezoensis. Porphyra yezoensis grows normally and is harvested for 3-4 batches. During the last harvest, the position of the harvesting blade is adjusted to harvest all the Porphyra yezoensis on the net to provide space for the growth of Ulva feldspar. From March to June, Ulva feldspar enters a rapid growth period, and the nets are properly washed, dried and fertilized;

[0047] 6) Harvesting Ulva longituba

[0048] After 70-80 days of cultivation, the harvest of Ulva longituba begins in mid-March, with one crop harvested every 10-15 days. From mid-March to mid-June, 6-8 crops of Ulva longituba are harvested.

[0049] Preferably, in step 2), the nets are dried in the sun once every 2 days for 2-3 hours each time during the seedling emergence period, and the nets are dried in the sun once every 3-5 days for 3-4 hours each time after the seedling emergence period.

[0050] Preferably, in the step 3), 5-7 cm of remaining algae are retained after each harvest; in the step 5), the length of the remaining algae after the last harvest does not exceed 1 cm; in the step 6), 10-12 cm of remaining algae are retained after each harvest, and all are harvested in the last harvest.

[0051] Preferably, in step 4), the color of the spore water in the release pool turns dark green, and the release is stopped when the number of spores in the downstream reaches 200-300 per field of view under a 100x microscope.

[0052] Preferably, in step 4), the mesh bag for growing Ulva is made of 60-100 mesh nylon filter mesh, 30-40 cm in length and 20-30 cm in width, and each mesh bag can hold 300-400 g of Ulva.

[0053] Preferably, in step 4), the collected spore water of Ulva feldspar is sprayed within 24 hours, diluted 5-6 times with seawater before spraying, and the spore water is fully stirred.

[0054] Preferably, in step 4), the ripening is accelerated by aerating the temporary culture pond, and the culture conditions are: light intensity 5000-6000lx, light cycle 10L:14D, culture water temperature 10-14°C, and temporary culture time 3-5 days; the release pond is provided with sand-filtered seawater at 7-10°C, and under stirring and aeration, irradiation is performed with a light intensity of 7000-8000lx for 0.5-1 hour.

[0055] Preferably, in the step 4), before spraying the spore water of Ulva feldspar and hanging the Ulva feldspar to grow vegetables, the breeding net is washed and dried.

[0056] Preferably, in step 4), the spraying of the Ulva feldspar spore water is performed during low tide.

[0057] Preferably, in step 5), fertilization is carried out by spraying, the nitrogen fertilizer is a nitrogen fertilizer seawater solution prepared with ammonium bicarbonate or urea with a nitrogen concentration of 18-20 mg / L, and the phosphate fertilizer is a phosphate fertilizer seawater solution prepared with potassium dihydrogen phosphate with a phosphorus concentration of 3-5 mg / L.

[0058] Embodiment 1

[0059] See attached Figure 1 and attached Figure 2In a mixed culture method of Porphyra yezoensis and Ulva longissima of the present invention, the culture equipment includes a culture raft frame 3 and a culture net 5. The culture raft frame 3 includes two buoys 31 arranged in parallel. The arrangement direction of the buoys 31 is the same as the tidal direction. The two buoys 31 are connected by cables 32. The buoys 31 are provided with buoys 4. The culture net 5 is arranged between the two buoys 31. Both sides of the culture net 5 are fixed to the cables 32 by fixing ropes 6. One culture raft frame 3 is provided with a culture net 5. Adjacent culture raft frames 3 are connected together by buoys 4. Both ends of the outermost buoys 31 are horizontally fixed to the foundation piles 1 by pile cables 2.

[0060] The mixed cultivation method of Porphyra yezoensis and Ulva longissima of the present invention comprises the following steps:

[0061] 1) Porphyra yezoensis cultivation

[0062] On September 25, 2020, in a certain aquaculture area in Rushan City, Weihai City, Shandong Province, the water temperature in the aquaculture area was 21°C, and conchospore seedlings of Porphyra yezoensis were collected on the aquaculture net and hung in the sea;

[0063] 2) Management of Porphyra yezoensis cultivation

[0064] During the breeding process, the nets are dried and washed according to the algae growth. The nets are dried 3 days after going into the sea. The nets are dried frequently during the emergence period, once every 2 days for 2 hours each time. After the emergence of the seedlings, the interval and time of drying the nets are gradually extended to once every 3 days for 3 hours each time. When there are a lot of algae and floating mud, the nets are washed and the frequency of drying the nets is appropriately increased.

[0065] 3) Harvesting Porphyra yezoensis

[0066] After 50 days of cultivation, the harvest of Porphyra yezoensis began on November 15, with one crop harvested every 15 days. From November 15 to December 30, four crops of Porphyra yezoensis were harvested, with 5 cm of remaining algae retained after each harvest.

[0067] 4) Collecting and planting Ulva longituba seedlings

[0068] On December 30, 2020, well-grown adults of Ulva longituba were collected and selected as seed vegetables and washed;

[0069] In the temporary culture pond, the fish are accelerated to mature and aerated. The culture conditions are: light intensity 5000lx, light cycle 10L:14D, culture water temperature 14℃, and temporary culture time 3 days;

[0070] The spores are released in a release tank, which is equipped with sand-filtered seawater at 7°C. Under stirring and aeration, the spore water is irradiated with a light intensity of 7000 lx for 0.5 hours, and the color of the spore water turns dark green. The release is stopped when the number of spores in each field of view under a microscope with a magnification of 100 times reaches 200;

[0071] The spore water is taken out and filtered with a 60-mesh filter, and the filtered spore water is collected. When the tide is low, the spore water of Ulva feldspar is sprinkled on the sea surface where Porphyra yezoensis is cultured. The collected spore water of Ulva feldspar is sprinkled within 24 hours. Before the sprinkle, the spore water is diluted 5 times with seawater and the spore water is fully stirred;

[0072] The long-necked Ulva vegetables obtained during the filtering process are collected, put into a mesh bag, and hung on a breeding net for breeding. The mesh bag for breeding the long-necked Ulva vegetables is made of a 60-mesh nylon filter net, with a length of 30 cm and a width of 20 cm. 300 g of long-necked Ulva vegetables are placed in each mesh bag;

[0073] Before spraying the spore water of Ulva feldspar and hanging the Ulva feldspar to grow vegetables, wash and dry the breeding net;

[0074] 5) Ulva longituba cultivation and management

[0075] From January to February 2021, the seawater temperature was relatively low. During this period, the growth of the young S. longituba on the culture net was slow, which did not affect the harvesting of Porphyra yezoensis. Porphyra yezoensis grew normally and was harvested for 4 more times. During the last harvest, the position of the harvesting blade was adjusted to harvest all the Porphyra yezoensis on the net. The length of the remaining algae was 1 cm, providing space for the growth of S. longituba. From March to June, S. longituba entered a rapid growth period, and the nets were washed, dried and fertilized appropriately;

[0076] Fertilization was carried out by spraying. The nitrogen fertilizer was a seawater solution of nitrogen fertilizer prepared with NH4HCO3 with a nitrogen concentration of 20 mg / L, and the phosphate fertilizer was a seawater solution of phosphate fertilizer prepared with KH2PO4 with a phosphorus concentration of 5 mg / L.

[0077] 6) Harvesting Ulva longituba

[0078] After 70 days of cultivation, the harvesting of Ulva longituba began on March 15, 2021, with one harvest every 15 days. From March 15 to June 10, six harvests of Ulva longituba were harvested. After each harvest, 10 cm of remaining algae were retained, and all were harvested in the last harvest.

[0079] Embodiment 2

[0080] The mixed cultivation method of Porphyra yezoensis and Ulva longissima of the present invention comprises the following steps:

[0081] 1) Porphyra yezoensis cultivation

[0082] On September 28, 2020, in a certain aquaculture area in Rongcheng City, Weihai City, Shandong Province, the water temperature in the aquaculture area was 19°C, and conchospore seedlings of Porphyra yezoensis were collected on the aquaculture net and hung in the sea;

[0083] 2) Management of Porphyra yezoensis cultivation

[0084] During the breeding process, the nets are dried and washed according to the algae growth. The nets are dried 5 days after going into the sea. The nets are dried frequently during the germination period, once every 2 days for 3 hours each time. After the germination, the interval and time of drying the nets are gradually extended to once every 5 days for 4 hours each time. When there are a lot of algae and floating mud, the nets are washed and the frequency of drying the nets is appropriately increased.

[0085] 3) Harvesting Porphyra yezoensis

[0086] After 57 days of cultivation, the harvest of Porphyra yezoensis began on November 24, with one crop harvested every 19 days. From November 24 to December 31, Porphyra yezoensis was harvested three times, with 7 cm of remaining algae retained after each harvest.

[0087] 4) Collecting and planting Ulva longituba seedlings

[0088] On December 26, 2020, well-grown adults of Ulva longituba were collected and selected as seed vegetables and washed;

[0089] In the temporary culture pond, the fish are accelerated to mature and aerated. The culture conditions are as follows: light intensity 6000lx, light cycle 10L:14D, culture water temperature 10℃, and temporary culture time 5 days;

[0090] The spores are released in a release tank, which is equipped with sand-filtered seawater at 10°C. Under stirring and aeration, the spore water is irradiated with a light intensity of 8000 lx for 1.0 hour, and the color of the spore water turns dark green. The release is stopped when the number of spores in each field of view under a microscope with a magnification of 100 times reaches 300;

[0091] The spore water is taken out and filtered with a 120-mesh filter, and the filtered spore water is collected. When the tide is low, the spore water of Ulva feldspar is sprinkled on the sea surface where Porphyra yezoensis is cultured. The collected spore water of Ulva feldspar is sprinkled within 24 hours. Before the sprinkle, the spore water is diluted 6 times with seawater and the spore water is fully stirred;

[0092] The long-necked Ulva vegetables obtained during the filtering process are collected, put into a mesh bag, and hung on a breeding net for breeding. The mesh bag for breeding the long-necked Ulva vegetables is made of a 100-mesh nylon filter net, with a length of 40 cm and a width of 30 cm. 400 g of long-necked Ulva vegetables are placed in each mesh bag;

[0093] Before spraying the spore water of Ulva feldspar and hanging the Ulva feldspar to grow vegetables, wash and dry the breeding net;

[0094] 5) Ulva longituba cultivation and management

[0095] From January to February 2021, the seawater temperature was relatively low. During this period, the growth of young spores of Ulva femoris on the culture net was slow, which did not affect the harvesting of Porphyra yezoensis. Porphyra yezoensis grew normally and was harvested for three more times. During the last harvest, the position of the harvesting blade was adjusted to harvest all the Porphyra yezoensis on the net. The length of the remaining algae was 0.8 cm, providing space for the growth of Ulva femoris. From March to June, Ulva femoris entered a rapid growth period, and the nets were properly washed, dried and fertilized;

[0096] Fertilization was carried out by spraying. The nitrogen fertilizer was a seawater solution of nitrogen fertilizer prepared with urea with a nitrogen concentration of 18 mg / L, and the phosphate fertilizer was a seawater solution of phosphate fertilizer prepared with KH2PO4 with a phosphorus concentration of 3 mg / L.

[0097] 6) Harvesting Ulva longituba

[0098] After 80 days of cultivation, the harvesting of Ulva longituba began on March 18, 2021, with one harvest every 10 days. From March 18 to June 5, 8 crops of Ulva longituba were harvested. After each harvest, 12 cm of remaining algae were retained, and all were harvested in the last harvest.

[0099] The data of Example 1 and Example 2 in the mixed cultivation method of Porphyra yezoensis and Ulva longituba are listed in Table 1. It can be seen from Table 1 that the Porphyra yezoensis obtained by the mixed cultivation method of Porphyra yezoensis and Ulva longituba of the present invention can be harvested 6-8 times, and the average per-acre yield of Porphyra yezoensis per crop is 800-850Kg, and the average selling price of Porphyra yezoensis is 7-8 yuan / Kg; however, when Porphyra yezoensis is cultivated alone according to the method of the present invention, when Porphyra yezoensis is harvested 8 times, the average per-acre yield of Porphyra yezoensis per crop is only 610Kg, and the average selling price of Porphyra yezoensis is 7 yuan / Kg; when Porphyra yezoensis is harvested 6 times, the average per-acre yield of Porphyra yezoensis per crop is 750Kg, and the average selling price of Porphyra yezoensis is 7 yuan / Kg; therefore, in the mixed cultivation method of Porphyra yezoensis and Ulva longituba of the present invention, Porphyra yezoensis grows well, has bright color, few impurities, high yield, and high selling price of fresh vegetables. The Ulva obtained by the mixed cultivation method of Porphyra yezoensis and Ulva longituba of the present invention can be harvested 6-8 times, and the average per-acre yield of Ulva longituba per crop is 700-760Kg, and the average selling price of Ulva longituba is 0.7-0.8 yuan / Kg; however, when Ulva longituba is cultivated alone according to the method of the present invention, when Ulva longituba is harvested 8 times, the average per-acre yield of Ulva longituba per crop is only 510Kg, and the average selling price of Ulva longituba is 0.7 yuan / Kg; when Ulva longituba is harvested 6 times, the average per-acre yield of Ulva longituba per crop is 660Kg, and the average selling price of Ulva longituba is 0.7 yuan / Kg. Therefore, in the mixed cultivation method of Porphyra yezoensis and Ulva longituba of the present invention, Ulva longituba grows well, has bright green color, few impurities, high yield, and high selling price of fresh vegetables. Therefore, the mixed culture method of Porphyra yezoensis and Ulva feldspar of the present invention not only realizes the production-increasing culture of Porphyra yezoensis, but also realizes the artificial culture of Ulva feldspar, thus greatly improving the economic benefits of fishermen's culture.

[0100] Table 1 Statistical table of experimental results of mixed breeding method

[0101]

[0102] Therefore, compared with the prior art, the beneficial effects of the present invention are as follows: the present invention realizes the mixed cultivation of Porphyra yezoensis and Ulva longissima in one cultivation sea area and one set of cultivation equipment, so that the cultivation sea area and the cultivation equipment are fully utilized, avoiding the idleness of the cultivation sea area and the cultivation equipment in winter and spring, and extending the cultivation period; this cultivation method is simple to operate, easy to master, convenient to implement, has low technical requirements, saves manpower and material resources, has high cultivation efficiency, and fully utilizes resources, which not only realizes the increased production cultivation of Porphyra yezoensis, but also realizes the artificial cultivation of Ulva longissima, achieves the increased production and increased income cultivation of seaweed, and improves the risk resistance of the seaweed cultivation industry.

[0103] 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 mixed culture method of Porphyra yezoensis and Ulva longissima, characterized in that: The following steps are involved: 1) Porphyra yezoensis cultivation In late September, when the water temperature in the aquaculture area is 19-21℃, collect the conchospore seedlings of Porphyra yezoensis onto the aquaculture net and hang the net in the sea; 2) Management of Porphyra yezoensis cultivation During the breeding process, the nets are dried and washed according to the algae growth. The nets are dried 3-5 days after being put into the sea. They are dried frequently during the germination period. After the germination period, the interval and time of drying the nets are gradually extended. When there are a lot of algae and floating mud, the nets are washed and the frequency of drying the nets is increased. 3) Harvesting Porphyra yezoensis After 50-60 days of cultivation, the harvest of Porphyra yezoensis begins in mid-November, with one crop harvested every 15-20 days. From mid-November to the end of December, 3-4 crops of Porphyra yezoensis are harvested. 4) Collecting and planting Ulva longituba seedlings At the end of December, well-grown adults of Ulva femoris were collected and selected as seed vegetables, washed, ripened in a temporary culture pond, and released spores in a release pond; taken out, filtered with a 60-120 mesh filter, spore water after filtration was collected, and the Ulva femoris spore water was sprinkled on the sea surface where Porphyra yezoensis was cultured; at the same time, the Ulva femoris seed vegetables obtained during the filtration process were collected, put into a net bag, and hung on a culture net for culture; 5) Ulva longituba cultivation and management The seawater temperature is low from January to February. During this period, the young spores of Ulva feldspar on the culture net grow slowly, which does not affect the harvesting of Porphyra yezoensis. Porphyra yezoensis grows normally and is harvested for 3-4 batches. During the last harvest, the position of the harvesting blade is adjusted to harvest all the Porphyra yezoensis on the net to provide space for the growth of Ulva feldspar. From March to June, Ulva feldspar enters a rapid growth period, and the nets are washed, dried and fertilized; 6) Harvesting Ulva longituba After 70-80 days of cultivation, the harvest of Ulva longituba begins in mid-March, with one crop harvested every 10-15 days. From mid-March to mid-June, 6-8 crops of Ulva longituba are harvested.

2. The mixed culture method of Porphyra yezoensis and Ulva longissima according to claim 1, characterized in that: In the step 2), the nets are dried in the sun once every 2 days during the seedling emergence period, for 2-3 hours each time; and the nets are dried in the sun once every 3-5 days after the seedlings emerge, for 3-4 hours each time.

3. The mixed culture method of Porphyra yezoensis and Ulva longissima according to claim 1, characterized in that: In the step 3), 5-7 cm of algae are retained after each harvest; in the step 5), the length of the algae remaining after the last harvest does not exceed 1 cm; in the step 6), 10-12 cm of algae are retained after each harvest, and all are harvested in the last harvest.

4. The mixed culture method of Porphyra yezoensis and Ulva longissima according to any one of claims 1 to 3, characterized in that: In the step 4), the color of the spore water in the release pool turns dark green, and the release is stopped when the number of spores in the downstream reaches 200-300 per visual field under a microscope at 100 times magnification.

5. The mixed culture method of Porphyra yezoensis and Ulva longissima according to any one of claims 1 to 3, characterized in that: In the step 4), the net bag for growing Ulva is made of a 60-100 mesh nylon filter net, with a length of 30-40 cm and a width of 20-30 cm. Each net bag can hold 300-400 g of Ulva.

6. The mixed culture method of Porphyra yezoensis and Ulva longissima according to any one of claims 1 to 3, characterized in that: In the step 4), the collected spore water of Ulva feldspar is sprayed within 24 hours, diluted 5-6 times with seawater before spraying, and the spore water is fully stirred.

7. The mixed culture method of Porphyra yezoensis and Ulva longissima according to any one of claims 1 to 3, characterized in that: In the step 4), the ripening is accelerated by aerating the temporary culture pond, and the culture conditions are: light intensity 5000-6000lx, light cycle 10L:14D, culture water temperature 10-14°C, and temporary culture time 3-5 days; the release pond is provided with sand-filtered seawater at 7-10°C, and under the action of stirring and aeration, irradiation is performed with a light intensity of 7000-8000lx for 0.5-1.0 hour.

8. The mixed culture method of Porphyra yezoensis and Ulva longissima according to any one of claims 1 to 3, characterized in that: In the step 4), before spraying the spore water of Ulva feldspar and hanging the Ulva feldspar to grow vegetables, the breeding net is washed and dried.

9. The mixed culture method of Porphyra yezoensis and Ulva longissima according to any one of claims 1 to 3, characterized in that: In the step 4), the spraying of the spore water of Ulva feldspar is carried out at low tide.

10. The mixed culture method of Porphyra yezoensis and Ulva longissima according to claim 1, characterized in that: In the step 5), fertilization is carried out by spraying, the nitrogen fertilizer is a nitrogen fertilizer seawater solution prepared with ammonium bicarbonate or urea with a nitrogen concentration of 18-20 mg / L, and the phosphate fertilizer is a phosphate fertilizer seawater solution prepared with potassium dihydrogen phosphate with a phosphorus concentration of 3-5 mg / L.

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