Manufacturing method of seaweed seed thread

Abstract

To provide a novel method for producing filamentous wakame seedlings.SOLUTION: A method for producing filamentous wakame seedlings with young wakame sporophores attached thereto includes, for example, the steps for: attaching wakame spores to filamentous attachment substrates capable of suspending in seawater, to obtain filamentous wakame seeds capable of suspending in seawater; and culturing the filamentous wakame seeds or the filamentous wakame seedlings that are obtained by growing the filamentous wakame seeds and capable of suspending in seawater, while allowing them to suspend in the seawater flowing in a culture device.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a method for producing seaweed seed thread used in seaweed cultivation. [Background technology]

[0002] Wakame cultivation generally involves the steps of: attaching wakame spores to a filamentous adhesion substrate to obtain wakame seed threads on which the wakame spores are attached; cultivating the wakame spores that have attached to the obtained wakame seed threads to obtain wakame seed threads on which wakame spores or wakame juvenile sporophytes are attached; further cultivating the wakame seed threads in the ocean before cultivation and acclimatizing them to the marine environment, a so-called "acclimatization cultivation" process; attaching the wakame seed threads on which the wakame juvenile sporophytes grown in the acclimatization cultivation are attached to a parent rope; and growing the wakame juvenile sporophytes in the ocean, for example, by suspending the parent rope to which the wakame seed threads on which the wakame juvenile sporophytes are attached to a raft. Among these processes, acclimatization is one of the most important processes indispensable for wakame cultivation, and if wakame seedlings are attached to a parent rope and cultivated without acclimatization, the wakame will likely grow poorly or die, which will affect the productivity of the wakame. On the other hand, acclimatization also carries the risk of the wakame seedlings dying, or "sprout drop," depending on the marine environment. In addition, acclimatization requires extensive work at sea, which is a heavy burden for farmers, so there is a demand for alternative methods to acclimatization that are more efficient and are expected to improve the quality and productivity of wakame.

[0003] As an alternative to acclimatization, a method has been considered in which seaweed seeds attached to seaweed seed threads are grown into young seaweed sporophytes that can withstand aquaculture. However, seaweed seed threads that use conventional Cremona threads or the like as an attachment substrate tend to sink to the bottom of the culture tank, causing the seaweed seed threads to gather on the bottom, resulting in poor growth of the seaweed seeds. The technique for cultivating wakame seaweed seedlings by floating them without them sinking is to infuse seaweed spores 1cm 2 10 per 4Patent Document 1 discloses a seaweed cultivation method that involves seeding spores or young embryos of brown algae on a plate at a high density of 10 or more, culturing them to form spore clumps in which a plurality of spores are linked together, or clumps in which the germinated bodies of the spores are entangled, and then peeling them off from the plate; and Patent Document 2 discloses a culture and cultivation method for cultivating young brown algae as seeds, comprising the steps of: (a) seeding spores or young embryos of brown algae on a substrate and cultivating them to form young, (b) peeling the young from the substrate, and (c) transferring the peeled young to a water tank and culturing the tank while injecting seawater and aerating the tank to keep each young floating.

[0004] However, these techniques require time and skill to detach the wakame seedlings from the flat plate or base. Even if the detached wakame seedlings are allowed to grow into wakame juvenile sporophytes, they are difficult to attach to the parent rope used for aquaculture via an attachment substrate because they do not have a substrate such as thread. Even if the wakame juvenile sporophytes themselves are forcibly sandwiched between the parent rope, the wakame juvenile sporophytes may be damaged or may not attach to the parent rope, which will affect the growth of the wakame. Therefore, there is a demand for a more practical wakame seedling technology that can contribute to improving the quality and productivity of wakame. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2002-176866 A [Patent Document 2] JP 2004-187574 A Summary of the Invention [Problem to be solved by the invention]

[0006] The object of the present invention is to provide novel (e.g., useful in suspension culture) wakame seed threads and wakame seed threads, a manufacturing method thereof, a culture method using the wakame seed threads and wakame seed threads (a manufacturing method of wakame seed threads), etc. [Means for solving the problem]

[0007] As a result of intensive research into the above-mentioned problems, the inventors have found that the above-mentioned problems can be solved by causing wakame spores to adhere using a filamentous adhesion substrate that is capable of floating in seawater (and further by carrying out a process of culturing the resulting wakame seed threads or wakame seed sapling threads that are capable of floating in seawater while floating them in flowing seawater in a culture device), and have developed the present invention based on this finding.

[0008] That is, the present invention relates to the following inventions, etc. [1] A method for producing wakame seed thread, comprising a process (hereinafter sometimes referred to as the attachment process, etc.) of attaching wakame spores to a thread-like attachment substrate capable of floating in seawater, and obtaining wakame seed thread (or wakame seed thread capable of floating in seawater) [seed thread (wakame seed thread, wakame seed thread capable of floating in seawater) composed of a thread-like attachment substrate capable of floating in seawater and wakame spores attached (attached) to the substrate].

[0009] [2] A method for producing wakame seed thread (e.g., wakame seed thread (A) or wakame seed thread (B) described below)) which includes at least a step (hereinafter sometimes referred to as the attachment step, etc.) of attaching wakame spores to a filamentous attachment substrate capable of floating in seawater to obtain wakame seed thread (or wakame seed thread capable of floating in seawater) [seed thread (wakame seed thread, wakame seed thread capable of floating in seawater) composed of a filamentous attachment substrate capable of floating in seawater and wakame spores attached (attached) to the substrate)] (or includes at least the attachment step described in [1]).

[0010] [3] The method described in [2] further comprises a step of raising (raising the wakame seed threads) after the attachment step to obtain wakame seed threads (or wakame seed threads capable of floating in seawater, hereinafter sometimes referred to as wakame seed threads (A) etc.) [wakame seed threads (Wakame seed threads (A)) composed of a thread-like attachment substrate capable of floating in seawater and wakame spores or wakame young sporophytes (Wakame young sporophytes (a)) attached (attached) to the substrate] (hereinafter sometimes referred to as a raising step, etc.).

[0011] [4] The method described in [2] or [3], further comprising a step (hereinafter sometimes referred to as a culture step, etc.) of culturing the wakame seed thread or wakame seed thread (wakame seed thread (A)) while floating it in flowing seawater in a culture device after the attachment step [or after the attachment step and further after the seedling raising step (seedling raising step (seedling raising step described in [3]))] {cultivating and obtaining wakame seed thread (wakame seed thread (B) or the like) on which wakame juvenile sporophytes (hereinafter sometimes referred to as wakame seed thread (b) or the like) are attached [cultivating and obtaining wakame seed thread (wakame seed thread (B)) composed of a thread-like attachment substrate capable of floating in seawater and wakame juvenile sporophytes (wakame juvenile sporophytes (b)) attached (attached) to the substrate} (hereinafter sometimes referred to as a culture step, etc.).

[0012] [5] A method for cultivating wakame seaweed using wakame seaweed seed threads (wakame seaweed seed threads (B)) consisting of a filamentous adhesion substrate capable of floating in seawater and wakame seaweed juvenile sporophytes (wakame seaweed juvenile sporophytes (b)) that have adhered (attached) to the substrate [or wakame seaweed seed threads (wakame seaweed seed threads (B)) after the cultivation step described in [4]].

[0013] [6] The method described in [5], which comprises a process of attaching wakame seed thread (wakame seed thread (B)) to a support (e.g., a parent rope) (hereinafter, sometimes referred to as the attachment process, etc.) and a process of installing the support (e.g., the parent rope) obtained in this process (attachment process) in the sea (hereinafter, sometimes referred to as the installation process, etc.).

[0014] [7] Wakame seed threads are composed of a filamentous adhesion substrate capable of floating in seawater and wakame spores attached to the substrate.

[0015] [8] A wakame seedling thread (Wakame seedling thread (A)) composed of a filamentous adhesion substrate capable of floating in seawater and a wakame spore or a wakame juvenile sporophyte (Wakame juvenile sporophyte (a)) adhered (attached) to the substrate.

[0016] [9] The wakame seed thread or wakame seedling thread described in [7] or [8], which is for use in floating culture (for floating culture in seawater).

[0017]

[10] Wakame seedling thread (Wakame seedling thread (B)) is composed of a filamentous adhesion substrate capable of floating in seawater and Wakame juvenile sporophytes (Wakame juvenile sporophytes (b)) that have adhered (attached) to the substrate.

[0018]

[11] The wakame seaweed seedling thread described in

[10] , which is for aquaculture (for cultivating wakame seaweed).

[0019]

[12] A substrate consisting of a filamentous substrate that can float in seawater and wakame seaweed that has grown (attached) to the substrate (seaweed substrate).

[0020]

[13] A support (seaweed growth support) composed of a support (e.g., a parent rope) and the seaweed growth substrate described in

[12] attached to the support (e.g., the parent rope).

[0021] The present invention includes, for example, the following invention: (1) A method for producing a wakame seed thread (wakame seed thread (B)) having a wakame juvenile sporophyte (wakame juvenile sporophyte (b)) attached thereto, the method comprising the steps of: attaching wakame spores to a filamentous attachment substrate capable of floating in seawater to obtain a wakame seed thread (wakame seed thread capable of floating in seawater); and culturing the wakame seed thread or the wakame seed thread capable of floating in seawater (wakame seed thread (A)) obtained by cultivating the wakame seed thread while floating it in flowing seawater in a culture device; (2) A method for cultivating wakame seaweed, comprising a step of attaching the wakame seaweed seedling thread on which the wakame seaweed juvenile sporophytes obtained by the manufacturing method described in (1) to a support (e.g., a parent rope) and a step of installing the support (e.g., the parent rope) obtained by the step in the sea; It may consist of. Effect of the Invention

[0022] According to the present invention, it is possible to provide novel (e.g., useful in suspension culture) wakame seed threads and wakame seed threads, methods for producing them, and a culture method using the wakame seed threads or wakame seed threads (method for producing wakame seed threads). Such wakame seed threads and wakame seed threads can be suitably used for floating culture (culture process). Wakame seed threads obtained through such floating culture (for example, wakame seed threads on which wakame juvenile sporophytes are attached, obtained by the method for producing wakame seed threads of the present invention) have good quality [for example, quality that allows for cultivation without acclimatization cultivation], and can be easily attached to a parent rope, etc., via an attachment substrate during cultivation. As a result, poor growth and death of the wakame are suppressed, and the quality and productivity of the wakame in wakame cultivation are improved. [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 is a photograph showing wakame seedling thread A after seedling cultivation before the start of culture. [Diagram 2] FIG. 2 is a photograph showing the growth state of seaweed seedlings in the seaweed seedling threads obtained in Examples 1 and 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] In the manufacturing method of the present invention for seaweed seed thread or seaweed seed thread (seaweed seed thread (A) and seaweed seed thread (B)), seaweed spores are first allowed to attach to a filamentous attachment substrate capable of floating in seawater to obtain seaweed seed thread (seaweed seed thread capable of floating in seawater). In other words, such a method of the present invention includes a step (attachment step) of allowing seaweed spores to attach to a filamentous attachment substrate capable of floating in seawater to obtain seaweed seed thread. In this specification, "wakame seed thread" refers to a filamentous substrate on which wakame spores grow.

[0025] There are no particular limitations on the filamentous growth substrate, so long as it is of a filamentous material and shape that can float in seawater and support the growth of wakame spores; examples of the material include plastics [e.g., olefin-based resins (e.g., polyethylene, polypropylene, etc.), non-olefin-based resins (e.g., polyamide resins, polyvinyl acetal resins, etc.)]. The filamentous adhesion substrate may be made of the same material (or the same type of material), or may be made of a combination of a number of different materials (for example, a combination of an olefin-based resin and a non-olefin-based resin). In particular, the filamentous adhesion substrate may be made of at least an olefin-based resin (for example, made of an olefin-based resin and a non-olefin-based resin) from the viewpoint of the balance between flotation and ease of adhesion.

[0026] The thread-like adhesion substrate may have a diameter of, for example, 0.1 mm or more, 0.3 mm or more, 0.5 mm or more, 10 mm or less, 5 mm or less, etc. The thread-like adhesion substrate may be a single yarn or a twisted yarn, and may be a twisted yarn in particular. In the twisted yarn, the diameters of the individual yarns may be the same or different. In particular, in consideration of ease of attachment, it is preferable that the diameters of the individual yarns are different. The filamentous adhesion substrate may be made of the same (or similar) material, or may be made of multiple different materials in terms of the balance between flotation and ease of adhesion (for example, each thread making up the twisted yarn may be made of a different material (for example, a combination of an olefin-based resin and a non-olefin-based resin)). The length of the filamentous adhesion substrate is not particularly limited, but may be, for example, 1 cm or more, 3 cm or more, 5 cm or more, 1 m or less, 50 cm or less, 30 cm or less, 20 cm or less, 10 cm or less, etc.

[0027] A representative example of a filamentous adhesion substrate (shape) is one having a diameter of 1 to 3 mm and a filamentous shape in which multiple fibers are twisted together. There is no particular limit to the length, but it is preferable to use one that has been pre-adjusted to a length of 5 to 10 cm, in terms of ease of flow in the culture device described below and ease of attachment to a support (such as a parent rope). In this specification, "floating in seawater" means maintaining a floating state on the seawater surface or in seawater. Whether or not a thread-like adhesion substrate or seaweed seed thread is capable of floating in seawater can be determined by putting the thread-like adhesion substrate or seaweed seed thread into a transparent container such as a beaker filled with seawater, stirring, and then letting it sink to the bottom of the container when left to stand. If the thread-like adhesion substrate or seaweed seed thread sinks to the bottom of the container when left to stand, it can be determined to be a thread-like adhesion substrate that does not float in seawater or a seaweed seed thread that does not float in seawater. If the thread-like adhesion substrate or seaweed seed thread maintains a floating state on the seawater surface or in seawater over time when left to stand, it can be determined to be a thread-like adhesion substrate that is capable of floating in seawater or a seaweed seed thread that is capable of floating in seawater. Examples of filamentous adhesion substrates that can float in seawater include commercially available products such as DR-2 (product name; diameter 2 mm; manufactured by Daiichi Seimo Co., Ltd.), and such commercially available products can also be used in the present invention.

[0028] The wakame spores are spores derived from wakame, which belongs to the genus Undaria and the family Polytrichum commune of the order Laminariales. The wakame species include Undaria pinnatifida, U. undarioides, and U. peterseniana. In the present invention, spores derived from any species of wakame can be preferably used. The wakame spores used in the present invention may be wakame spores used in conventional wakame cultivation, such as wakame zoospores released from mekabu, and wakame gametophytes that have been attached to a substrate in advance and then germinated into gametophytes and cultured into free gametophytes.

[0029] There are no particular limitations on the method (adhesion process) for causing wakame spores to adhere (attach) to a filamentous adhesion substrate capable of floating in seawater, but examples of such a method include a method of immersing a filamentous adhesion substrate capable of floating in seawater in a liquid matter or liquid (such as a solution) containing wakame spores, and a method of applying or spraying a liquid matter or liquid (such as a solution) containing wakame spores to a filamentous adhesion substrate capable of floating in seawater. As described below, when the seedling raising step is carried out by fixing the seedlings to a frame or the like after the attachment step, the attachment step may be carried out while the seedlings are fixed to the frame or the like. The number of seaweed spores attached to a filamentous adhesion substrate capable of floating in seawater is not particularly limited as long as the number of spores that can be used for seaweed cultivation is sufficient, and when taking into consideration the yield of seaweed and the quality of seaweed (shape of the algae, presence or absence of wrinkles on the surface of the thallus, etc.), for example, it is preferably 5 to 20 spores / 10 cm, more preferably 8 to 12 spores / 10 cm. If the number is within the above range, the seaweed will grow longer by being encouraged to grow vertically in an attempt to avoid mutual coverage, and further grown seaweed will have a shape with fewer wrinkles on the surface of the thallus, which is preferable.

[0030] In the manufacturing method of the present invention for producing wakame seed threads (wakame seed threads (A), wakame seed threads (B)), after the step of attaching wakame spores to a filamentous attachment substrate capable of floating in seawater to obtain wakame seed threads capable of floating in seawater (attachment step) (and before the culture step), a step of cultivating the wakame seed threads to obtain wakame seed threads (wakame seed threads (A)) [wakame seed threads (A) grown to wakame spores or wakame young sporophytes (wakame young sporophytes (a))] (raising step) may be further carried out (included). In this specification, "wakame seed" refers to wakame spores or wakame young sporophytes obtained by cultivating wakame spores, and "wakame seed threads" refers to a filamentous attachment substrate on which wakame seed threads are attached.

[0031] As a method for cultivating the wakame seed threads and growing them into wakame spores or young wakame sporophytes (young wakame sporophytes (a)), the cultivation method used for conventional wakame seed threads for wakame cultivation can be adopted. In the seedling raising step, conditions (seedling raising conditions) such as temperature (seedling raising temperature), the presence or absence of separate light irradiation and its amount (light amount), the presence or absence of ventilation and its amount, and period may be appropriately selected.

[0032] For example, when forming wakame spores from wakame gametophytes and growing them into wakame spores or wakame young sporophytes (e.g., wakame spores or wakame young sporophytes with a size of about 1 to 5 mm), the seawater temperature should be 5°C or higher (e.g., 10°C or higher, 15°C or higher, 30°C or lower, 25°C or lower, 18 to 20°C), and the light intensity should be 10 μmol / m 2 / s or more (e.g., 20 μmol / m 2 / s or more, 30μmol / m 2 / s or more, 150μmol / m 2 / s or less, 100μmol / m 2 / s, less than 90 μmol / m 2 / s or less, 45~80 μmol / m 2 / s) for a predetermined period of time or more [for example, 3 days or more, 1 week or more, 2 weeks or more, 3 weeks or more, 30 days or more (for example, 30 days)] can be employed.

[0033] The light amount may be an average value (average light amount). Also, the light amount may be an amount smaller than the light amount in the culture step described below.

[0034] In the seedling raising process, nutrients may be added to the seawater as necessary.

[0035] The seedling raising process can be carried out in seawater, which may or may not be flowing.

[0036] In addition, during the seedling raising process, the seawater may or may not be exchanged, but it is preferable that it is exchanged.

[0037] Furthermore, the seedling raising process may usually be carried out without allowing the wakame seed thread to float or flow (by restricting the floating or flow of the wakame seed thread) [for example, by fixing the wakame seed thread (by fixing it to a fixing means such as a frame)].

[0038] Through these adhesion and seedling cultivation processes, wakame seed threads [wakame seed threads composed of a filamentous adhesion substrate capable of floating in seawater and wakame spores attached (adhered) to the substrate] and wakame seedling threads (wakame seedling threads (A)) [wakame seedling threads (Wakame seedling threads (A)) composed of a filamentous adhesion substrate capable of floating in seawater and wakame spores or wakame young sporophytes (Wakame young sporophytes (a)) attached (adhered) to the substrate] are obtained.

[0039] The wakame seed thread and wakame seed thread (wakame seed thread (A)) thus obtained have wakame spores, wakame spores or wakame young sporophytes (wakame young sporophytes (a)) attached to the filamentous attachment substrate, and usually float (can float) in seawater. When the wakame seed thread is grown and allowed to grow into a wakame spore or wakame young sporophyte (wakame young sporophyte (a)), the size (length) of the wakame spores or wakame young sporophytes (wakame young sporophytes (a)) attached to the wakame seed thread (wakame seed thread (A)) may be 0.5 mm or more, 20 mm or less, 10 mm or less, 8 mm or less, etc., and 1 to 5 mm is preferable. The size (length) of such a wakame spore or wakame young sporophyte (wakame young sporophyte (a)) is usually smaller than the size (length) of the wakame young sporophyte (b) described below. In addition, whether or not the seaweed seed thread (seaweed seed thread (A)) is capable of floating in seawater can be confirmed using a method similar to that for determining whether or not the thread-shaped attachment substrate is capable of floating in seawater or whether or not the seaweed seed thread is capable of floating in seawater.

[0040] In the manufacturing method of the present invention for seaweed seed thread (seaweed seed thread (B)), the next step is to culture the seaweed seed thread or seaweed seed thread (seaweed seed thread (A)) obtained in the above steps (attachment step, seedling cultivation step) while floating it in flowing seawater in a culture device (culture step).

[0041] In the culture process, the wakame seed thread or wakame seed thread (wakame seed thread (A)) obtained in the above process may be used as is, or, taking into consideration the fluidity in the culture device, it may be adjusted to a length of preferably 5 to 10 cm.

[0042] The culture device used in the process of culturing seaweed seed threads or seaweed seed threads (seaweed seed threads (A)) while suspending them in flowing seawater in the culture device is not particularly limited as long as it can make seawater flow, but it usually includes (has) a tank (container). Examples of materials for such a tank (culture tank) include plastic (acrylic, polycarbonate, etc.), glass, FRP (fiber reinforced plastic), etc.

[0043] From the standpoint of efficient light supply and visibility, the tank may be transparent at least in transparent parts (e.g., the side surfaces (side portions), the side surfaces (side portions) and the bottom surface (bottom portion)).

[0044] The shape of the culture tank is preferably circular (cylindrical, columnar) in terms of the fluidity of seawater. In addition, the tank may or may not have an opening. For example, the tank may have an opening in its upper portion (upper surface).

[0045] The capacity of the culture tank is preferably 500 L or more, more preferably 1000 L or more, from the viewpoint of productivity of wakame seed thread. The culture device preferably has a device (fluidization device) for fluidizing the seawater in the culture tank. Examples of such devices include an air pump that feeds air into the seawater in the culture tank, a discharge / supply pump that discharges seawater from the culture tank and supplies seawater to the culture tank, and a stirring device that stirs the seawater in the culture tank. The culture device preferably has a water thermometer that measures the seawater temperature. The culture device preferably has lighting for supplying light into the culture tank and a light-shielding device for blocking light, and preferably has a photon meter that measures the amount of light. The culture device preferably has a filtration device that filters the seawater in the culture tank. There is no particular limitation on the location of the culture device, and it may be indoors or outdoors.

[0046] The culture step may be performed in an open system or a closed system, depending on the specifications of the apparatus (tank), etc. Typically, the culture step may be performed in an open system (e.g., with the top open) using a tank having an opening (e.g., an opening at the top).

[0047] Examples of the method for culturing wakame seed threads or wakame seed threads (wakame seed threads (A)) while suspending them in flowing seawater in a culture device include (1) a method for culturing by feeding gas (air, etc.) into seawater filled in a culture tank to cause the seawater to flow, (2) a method for culturing by discharging and supplying seawater while maintaining (particularly keeping it constant) the seawater filled in the culture tank to cause the seawater to flow, (3) a method for culturing by stirring the seawater filled in the culture tank to cause the seawater to flow, and (4) a combination of these methods. Among these, at least method (2) [for example, a method for culturing by using a drainage / supply pump, etc. to cause the seawater to flow while maintaining the seawater constant, thereby discharging and supplying seawater] is preferred in terms of supplying fresh seawater to the culture tank and maintaining a good growth environment for the wakame seedlings.

[0048] When the seawater in the culture tank is discharged and new seawater is supplied while maintaining (particularly keeping constant) the amount of seawater in the culture tank, the ratio of the amount of new seawater supplied per day (L) to the amount of seawater maintained (particularly kept constant) in the culture tank (L) is defined as the "flow rate ratio," and the flow rate ratio (amount of new seawater supplied (L) / amount of seawater maintained constant in the culture tank (L)) is preferably 10 or more, and more preferably 20 or more.

[0049] If the ratio of the total length (cm) of wakame seed threads or wakame seedling threads (or filamentous attachment substrate) to the volume of seawater (L) in the culture tank during cultivation is defined as the "culture density," the culture density (total length (cm) of wakame seed threads or wakame seedling threads / volume of seawater in the culture tank (L)) may be 80 cm / L or less (e.g., 60 cm / L or less, 50 cm / L or less), etc., in order to suppress the attachment of diatoms and maintain a good growth environment for the wakame seedlings, and is preferably 20 to 40 cm / L, and more preferably 30 to 40 cm / L.

[0050] The seawater used for the culture (including the seawater supplied in the above method (2)) is preferably at least 5°C (for example, at least 10°C, at least 15°C, at most 30°C, at most 25°C, at most 10 to 20°C) in order to provide a seawater temperature suitable for the growth of wakame seedlings. A fertilizing material may be added to the seawater used for the culture in order to promote the growth of the wakame seedlings. Examples of the fertilizing material include ammonium nitrate, ammonium sulfate, urea, potassium nitrate, and calcium superphosphate. As a method for adding the fertilizing material, for example, in the case of ammonium nitrate, it is preferable to use 0.01 g or more per day per 1 L of seawater in the culture tank. It is preferable to filter the seawater used for the culture using a filtration device.

[0051] During cultivation, in order to provide a constant amount of light to the wakame seedlings, light may be irradiated onto the seawater in the cultivation tank using lighting or the like, and when culturing outdoors, the amount of light may be adjusted by using a shading device or the like for the seawater in the cultivation tank. The amount of light at the seawater surface in the cultivation tank is set to 50 μmol / m in order to simultaneously promote the growth of the wakame seedlings and inhibit the occurrence of diatoms. 2 / s or more, 10000μmol / m 2 / s or less, 8000μmol / m 2 / s or less, 5000μmol / m 2 / s or less, 3000μmol / m 2 / s or less, 2000μmol / m 2 / s or less, 1500μmol / m 2 / s or less, 1000μmol / m 2 / s or less, 800μmol / m 2 / s or less, and 100 to 500 μmol / m 2 / s is preferred, and 100 to 300 μmol / m 2 / s is more preferable. Note that such a light amount may be an average value (average light amount).

[0052] The culture period is usually 10 to 45 days, preferably 15 to 40 days, and more preferably 20 to 30 days.

[0053] Through this cultivation process, wakame seedling threads (wakame seedling threads (B)) [wakame seedling threads (B)) consisting of a thread-like attachment substrate capable of floating in seawater and wakame juvenile sporophytes (wakame juvenile sporophytes (b)) attached (attached) to the substrate] are obtained.

[0054] The wakame seed threads thus obtained contain young wakame sporophytes and can be used for aquaculture without undergoing acclimation culture. The size (length) of the wakame juvenile sporophyte (wakame juvenile sporophyte (b)) may be, for example, more than 0.5 cm (eg, 0.8 cm or more) or 10 cm or less, and preferably 1 to 5 cm. In addition, since the wakame seed thread (wakame seed thread (B)) also has a thread-like adhesion substrate that can float in seawater, it can usually float in seawater. Whether or not it can float in seawater can be confirmed using the same method as described above. Another embodiment of the present invention is a method for cultivating wakame seaweed, which includes a step (attaching step) of attaching the wakame seaweed seed thread (wakame seaweed seed thread (B)) on which the wakame seaweed juvenile sporophyte (wakame seaweed juvenile sporophyte (b)) has grown to a support (master rope, etc.), and a step (installation step) of installing the support (master rope, etc.) obtained in the above step (attaching step) in the sea.

[0055] The support used in the attachment step is usually called a master rope. Such a support (master rope) may be one that is usually used in wakame seaweed farming, and there are no particular limitations on its material and shape. Specific materials include, for example, chemical fibers such as polyester and vinylon. Specific shapes include, for example, rope-like structures with a diameter of 20 to 50 mm formed by twisting together multiple ropes, and although the length varies depending on the farm, it is generally about 50 to 200 m. Furthermore, a master rope equipped with a steel wire in the center of the rope-like master rope can also be used.

[0056] There is no particular limitation on the method of attaching the seaweed seed thread (seaweed seed thread (B)) on which seaweed juvenile sporophytes (seaweed juvenile sporophytes (b)) have grown to the support (parent rope), but any conventional method used in seaweed cultivation can be adopted. For example, the seaweed seed thread can be attached by sandwiching it between the twisted ropes of the parent rope, by directly fixing it to the parent rope with a tacker or the like, or by wrapping it around the parent rope and then sandwiching it between the ropes or fixing it with a tacker or the like. In this case, it is preferable to attach the seaweed seed thread so that the total length of the seaweed seed thread is 5 to 10 cm for a 60 cm length of the parent rope. For example, if each seaweed seed thread is 5 cm long, it is preferable to attach 1 to 2 threads for a 60 cm length of the parent rope.

[0057] The method of installing the support (mother rope) with the seaweed seed thread (seaweed seed thread (B)) on which the thus obtained seaweed juvenile sporophytes (seaweed juvenile sporophytes (b)) are attached in the sea can be the same as that used in conventional seaweed cultivation. For example, one end of the mother rope with the seaweed seed thread attached is tied to a rope stretched toward the water surface from an anchor installed on the seabed of the seaweed cultivation site, and the other end is tied to a rope stretched from another anchor on the water surface while the mother rope is stretched horizontally on the sea surface for the length of the mother rope. In this case, the mother rope with the seaweed seed thread attached can be installed at a depth of 1 to 2 m using a float, or another method can be used.

[0058] As described above, the parent rope with the seaweed seedling thread attached installed at the seaweed farm can be used to farm seaweed using the method used in conventional seaweed farming. For example, when the water temperature generally falls below about 18°C, which is usually mid-October to late November in the Sanriku coast, farming begins, and after about three months, it is harvested between March and the end of April.

[0059] The wakame cultivated by the wakame cultivation method of the present invention can be harvested by conventional methods and can be further processed by conventional methods. The harvested raw wakame can be processed into processed products such as boiled frozen wakame and boiled salted wakame by conventional processing such as blanching, freezing, salting, etc., and further processed products such as cut dried wakame can be obtained by processing such as washing, cutting, drying, etc. The wakame cultivated by the wakame cultivation method of the present invention can obtain quality and yields equal to or higher than those obtained by conventional cultivation requiring acclimatization. Therefore, the aquaculture operator is freed from the trouble and risk of acclimatization cultivation and can improve the quality and productivity of the wakame.

[0060] The present invention also includes the following inventions (product inventions):

[0061] A seaweed seed thread (e.g., seaweed seed thread for use in floating culture (culture process)) that is composed of a thread-like adhesion substrate capable of floating in seawater and seaweed spores that have adhered (attached) to the substrate.

[0062] A wakame seedling thread (wakame seedling thread (A)) composed of a filamentous adhesion substrate capable of floating in seawater and wakame spores or wakame young sporophytes (wakame young sporophytes (a)) that have adhered (attached) to the substrate [for example, a wakame seedling thread (wakame seedling thread (A)) for use in floating culture (culture process)].

[0063] A wakame seedling thread (wakame seedling thread (B)) composed of a thread-like adhesion substrate capable of floating in seawater and wakame juvenile sporophytes (wakame juvenile sporophytes (b)) that have adhered (attached) to the substrate [for example, a wakame seedling thread for aquaculture (for cultivating wakame) (wakame seedling thread (B))].

[0064] The epiphytic substrate (wakame epiphytic substrate) is composed of a filamentous epiphytic substrate that can float in seawater and wakame that has grown (attached) to the substrate.

[0065] A support (seaweed growth support) composed of a support (e.g., a parent rope) and the seaweed growth substrate attached to the support (e.g., the parent rope).

[0066] The aspects of the constituent elements in these inventions (e.g., adhesion substrate, wakame spores, wakame seed threads, wakame spore bodies, wakame young sporophytes, wakame seed threads, support bodies, etc.) are all the same as described above, including preferred aspects (and can be selected from the same).

[0067] In addition, such objects of the invention (seaweed seed threads, seaweed seed threads, seaweed adhesion substrates, seaweed adhesion support bodies) can be produced, for example, by the methods described above.

[0068] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these. EXAMPLES

[0069] [Selection of filamentous substrates that can float in seawater] As thread-like adhesion substrates, 5 cm of each of Cremona thread (product name; diameter 1.4 mm; manufactured by Daiichi Seimo Co., Ltd.) and DR-2 (product name; diameter 2 mm; manufactured by Daiichi Seimo Co., Ltd.) were placed into a 500 mL beaker filled with seawater and stirred for 30 seconds. After that, they were left to stand for 5 minutes to check whether they could float in the seawater. As a result, it was found that the Cremona thread sank to the bottom of the beaker and did not float in the seawater. On the other hand, DR-2 floated near the seawater surface, indicating that it could float in seawater.

[0070] [Preparation of wakame spore-containing solution] Approximately 0.1 g of female and 0.1 g of male wakame gametophytes (Iwate Prefecture strain) were added to 10 g of sterilized seawater, and crushed for 2 minutes at 5000 rpm using a homogenizer (model: Pro200 homogenizer; manufactured by Pro Scientific), and 90 g of sterilized seawater was added to obtain approximately 100 g of wakame spore-containing solution. When the obtained wakame spore-containing solution was examined using an inverted microscope, the cell count of each of the crushed male and female spores was 5 to 30 cells.

[0071] [Production of seaweed seed thread 1] (1) Adhesion of wakame spores to filamentous substrates A frame was made using polyvinyl chloride piping, and DR-2 (product name; diameter 2 mm; manufactured by Daiichi Seimo Co., Ltd.) was wrapped around and fixed as a thread-like attachment substrate around the frame. The wakame spore-containing solution was then applied to the DR-2 with a brush to produce wakame seed thread A.

[0072] (2) Raising wakame seedlings Wakame seed thread A fixed to a frame was immersed in UV-sterilized seawater at a temperature of 18°C ​​and exposed to a light intensity of 45 μmol / m 2 The seedlings were grown for 30 days under conditions of 0.1 s and 0.2 s with aeration. The seawater was changed once every 3 to 10 days, and 0.2 mL of Nori Seed (product name; Daiichi Seimo Co., Ltd.) was added per 1 L of seawater as a nutrient when the seawater was changed. After seedling growth was completed, it was confirmed that the wakame seedling thread A obtained had spores of about 5 mm in size that had germinated from the wakame spores, with 30 to 100 spores attached per 1 cm of the wakame seedling thread A. A photograph of the wakame seedling thread A adjusted to about 7 cm is shown in Figure 1.

[0073] (3) Seawater floatation test 5 cm of seaweed seed thread A was placed in a 500 mL beaker filled with seawater and stirred for 30 seconds. After leaving it to stand for 5 minutes, it floated near the surface of the seawater, indicating that seaweed seed thread A was capable of floating in seawater.

[0074] [Production of seaweed seed thread 2] (1) Adhesion of wakame spores to filamentous substrates A frame was made using polyvinyl chloride piping, and Cremona thread (product name: diameter 1.4 mm; manufactured by Daiichi Seimo Co., Ltd.) was wrapped around and fixed as a thread-like attachment substrate around the frame. The seaweed spore-containing solution was then applied to the Cremona thread with a brush to produce seaweed seed thread B.

[0075] (2) Raising wakame seedlings Wakame seed thread B fixed to the frame was immersed in UV-sterilized seawater at a temperature of 18°C ​​and exposed to a light intensity of 45 μmol / m 2The seedlings were grown under conditions of 0.1 s and 0.2 s with aeration for 30 days. The seawater was changed once every 3 to 10 days, and 0.2 mL of Nori Seed (product name; Daiichi Seimo Co., Ltd.) was added per 1 L of seawater as a nutrient when the seawater was changed. After seedling growth was completed, it was confirmed that spores of about 5 mm in size that had germinated from the wakame spores were attached to the obtained wakame seedling thread B, with 30 to 100 pieces attached per 1 cm of the wakame seedling thread B.

[0076] (3) Seawater floatation test 5cm of seaweed seed thread B was placed in a 500mL beaker filled with seawater and stirred for 30 seconds. After leaving it to stand for 5 minutes, it sank to the bottom of the beaker, indicating that seaweed seed thread B did not float in the seawater.

[0077] [Production of wakame seed threads by suspension culture in a culture device 1] (1) Example 1 A 500L Artemia tank (product name: Artemia hatching tank; manufactured by Earth Co.) was installed outdoors as a culture tank, and after filling it with 500L of seawater, about 2280 pieces of Wakame seedling thread A, which had been removed from the frame and adjusted to about 7 cm each, were added (culture density: 32 cm / L). Next, while aerating the seawater in the culture tank with an air pump, 4800L / day of seawater was discharged from the culture tank with a discharge pump to maintain the seawater volume in the culture tank at 500L, while 4800L / day of seawater was supplied to the culture tank with a supply pump (flow rate ratio: 9.6), and culture was started while the Wakame seedling thread A was suspended in the seawater. During the cultivation, a photon meter (product name: Light Analyzer; manufactured by Nippon Medical and Chemical Equipment Manufacturing Co., Ltd.) was used to measure the amount of light on the seawater surface in the cultivation tank. The cultivation tank was shaded with a light-shielding net during the day and illuminated at night, so that the average daytime light intensity on the seawater surface in the cultivation tank was 100-200 μmol / m 2 The seawater temperature during the culture was 18-24°C. The wakame seedling threads obtained 17 days after the start of culture were taken out and the growth status of the wakame juvenile sporophytes was confirmed. A photograph of the wakame seedling threads at that time is shown in Figure 2.

[0078] (2) Example 2 A 500L Artemia tank (product name: Artemia hatching tank; manufactured by Earth Co., Ltd.) was installed indoors as a culture tank, and after filling it with 500L of seawater, about 2280 pieces of seaweed seed thread A, which had been removed from the frame and adjusted to about 7 cm each, were added (culture density: 32 cm / L). Next, while aerating the seawater in the culture tank with an air pump, 4800 L / day of seawater was discharged from the culture tank with a discharge pump to maintain the seawater volume in the culture tank at 500 L, while 4800 L / day of seawater was supplied to the culture tank with a supply pump (flow rate ratio: 9.6), and culture was started while floating the seaweed seed thread A in the seawater. During the culture, a photon meter (product name: Light Analyzer; manufactured by Nippon Medical and Chemical Equipment Co., Ltd.) was used to measure the amount of light on the seawater surface in the culture tank, and white LED light was irradiated onto the culture tank to measure the amount of light on the seawater surface in the culture tank at 50 to 150 μmol / m 2 The seawater temperature during the culture was 14-19°C. The wakame seedling threads obtained 17 days after the start of culture were taken out and the growth status of the wakame juvenile sporophytes was confirmed. A photograph of the wakame seedling threads at that time is shown in Figure 2.

[0079] (3) Comparative Example 1 A 500L Artemia tank (product name: Artemia hatching tank; manufactured by Earth Co.) was installed outdoors as a culture tank, and after filling it with 500L of seawater, about 2280 pieces of seaweed seed thread B, which had been removed from the frame and adjusted to about 7 cm each, were added (culture density: 32 cm / L). Next, while aerating the seawater in the culture tank with an air pump, 4800 L / day of seawater was discharged from the culture tank with a discharge pump to keep the seawater volume in the culture tank at 500 L, and 4800 L / day of seawater was supplied to the culture tank with a supply pump (flow rate ratio: 9.6). However, the seaweed seed thread B sank to the bottom of the culture tank and could not be cultured while floating in the seawater. After that, the seaweed seed threads continued to be densely packed on the bottom of the culture tank, and the culture was discontinued because future growth of the seaweed seedlings was not expected.

[0080] As shown in Figures 1 and 2, the wakame seed threads obtained in Examples 1 and 2 grew well from the start of cultivation, and both were wakame seed threads with quality suitable for cultivation. In particular, the wakame seed threads obtained in Example 1 were in good condition. This was because the light intensity on the seawater surface in the cultivation tank was 200 μmol / m 2 / s, which is thought to be one of the reasons for the promotion of the growth of the wakame seedlings. In addition, in Comparative Example 1, floating culture could not be performed in the culture device, and wakame seedlings that could withstand aquaculture could not be grown using the wakame seedling threads that used the conventional thread-like adhesion substrates that do not float in seawater, such as Cremona threads.

[0081] [Production of wakame seed threads by suspension culture in a culture device 2] (1) Example 3 A 1000L Artemia tank (product name: Artemia hatching tank; manufactured by Earth Co.) was installed outdoors as a culture tank, and after filling it with 1000L of seawater, about 9600 seaweed seed threads A, which had been removed from the frame and adjusted to about 5 cm each, were added (culture density: 48 cm / L). Next, while aerating the seawater in the culture tank with an air pump, 24000L / day of seawater was discharged from the culture tank with a discharge pump to keep the seawater volume in the culture tank at 1000L, and 24000L / day of seawater was supplied to the culture tank with a supply pump (flow rate ratio: 24), and culture was started while the seaweed seed threads A were suspended in the seawater. During the cultivation, a photon meter (product name: Light Analyzer; manufactured by Nippon Medical and Chemical Equipment Manufacturing Co., Ltd.) was used to measure the amount of light on the seawater surface in the cultivation tank. The cultivation tank was shaded with a light-shielding net during the day and illuminated at night, so that the average daytime light intensity on the seawater surface in the cultivation tank was 100-200 μmol / m 2 The seawater in the culture tank was filtered using a 1 μm filter to adjust the flow rate to 100 / s. The seawater temperature during culture was 8-12°C. 29 days after the start of culture, 10 pieces of each wakame seed thread were taken out to check the growth status of the wakame juvenile sporophytes and to measure their mass. The results of the growth status of the wakame seed and the average mass (g) per wakame seed thread are shown in Table 1.

[0082] (2) Example 4 The seaweed seed threads were produced in the same manner as in Example 3, except that the number of seaweed seed threads A added was changed to about 6,400, the culture density was changed to 32 cm / L, and a filter was not used. The growth state of the seaweed juvenile sporophytes was confirmed and the weight was measured. The results of the growth state of the seaweed seeds and the average mass (g) per seaweed seed thread are shown in Table 1.

[0083] (3) Example 5 The seaweed seed threads were produced in the same manner as in Example 3, except that the number of seaweed seed threads A added was changed to about 3,200, the culture density was changed to 16 cm / L, and a filter was not used. The growth state of the seaweed juvenile sporophytes was confirmed and the mass was measured. The results of the growth state of the seaweed seeds and the average mass (g) per seaweed seed thread are shown in Table 1.

[0084] (4) Example 6 The number of seaweed seed threads A put in was changed to about 6,400, the culture density was changed to 32 cm / L, a filter was not used, and the culture tank was not shaded by a shading net. The average daily light intensity on the seawater surface in the culture tank was changed to 2,000 to 5,000 μmol / m 2 The seaweed seed threads were produced in the same manner as in Example 3, except that the temperature was adjusted to 100° C. / s, and the growth state of the seaweed juvenile sporophytes was confirmed and the mass was measured. The results of the growth state of the seaweed seeds and the average mass (g) per seaweed seed thread are shown in Table 1.

[0085] [Table 1]

[0086] As shown in Table 1, all of the seaweed seed threads obtained in Examples 3 to 6 had the quality required for cultivation. Among these, the seaweed seed threads obtained in Examples 3 and 4 were free of diatoms and in good growth condition, and the seaweed seed thread obtained in Example 4 was particularly excellent in growth condition.

[0087] [Wakame seaweed cultivation using seaweed seed thread 1 (farm: Utatsu, Miyagi Prefecture)] (1) Example 7 The wakame seedling thread (about 7 cm) obtained in Example 1 was fixed to a 60 cm master rope at intervals using a tacker. In mid-November, the master rope with the wakame seedling thread attached was set at a water depth of about 1.5 m, and culture was started. In early March of the following year, the wakame was harvested, and the quality of the wakame was evaluated.

[0088] (2) Comparative Example 2 Wakame seedling thread B was set at a depth of about 2m, and cultured in the ocean for two weeks. Next, the wakame seedling threads (approximately 5cm) obtained from the culture were fixed at intervals to a 40cm master rope. In mid-November, the master rope with the wakame seedling threads attached was set at a depth of about 1.5m, and culture began. In early March of the following year, the wakame was harvested, and its quality was evaluated.

[0089] The wakame obtained in Example 7 was equivalent to the wakame obtained in Comparative Example 2 in terms of quality such as color and size, and yield.

[0090] [Wakame seaweed farming using seaweed seedling thread 2 (farm: Koshikirai, Iwate Prefecture)] (1) Example 8 The wakame seedling thread (about 7 cm) obtained in Example 1 was fixed to a 25 cm master rope at intervals using a tacker. In late November, the master rope with the wakame seedling thread attached was set at a water depth of about 1.5 m, and culture was started. In early April of the following year, the wakame was harvested and the quality of the wakame was evaluated.

[0091] (2) Comparative Example 3 Except for changing the farming site to Oshikurai, Iwate Prefecture, changing the start of farming to late November, and changing the harvesting time to early April, wakame was cultivated in the same manner as in Comparative Example 2, and the wakame yield and quality were evaluated.

[0092] The wakame obtained in Example 8 was larger than the wakame obtained in Comparative Example 3, had better quality, and was in greater yield.

[0093] [Wakame seaweed farming using seaweed seedling thread 3 (farm: Matsushima, Miyagi Prefecture)] (1) Example 9 The wakame seedling thread (about 7 cm) obtained in Example 1 was fixed to a 50 cm master rope at intervals using a tacker. In early December, the master rope with the wakame seedling thread attached was set at a water depth of about 1.5 m, and culture was started. In mid-April of the following year, the wakame was harvested and the quality of the wakame was evaluated.

[0094] (2) Comparative Example 4 Except for changing the farming site to Matsushima, Miyagi Prefecture, changing the start of farming to early December, and changing the harvesting time to mid-April, wakame was cultivated in the same manner as in Comparative Example 2, and the wakame yield and quality were evaluated.

[0095] The wakame obtained in Comparative Example 4 had many pieces that lost their color, but the wakame obtained in Example 9 had no loss of color and was of good quality. The yields were also comparable for both.

Claims

1. The present invention provides a method for producing seaweed seed threads on which seaweed juvenile sporophytes are attached, the method comprising the steps of: attaching seaweed spores to a filamentous attachment substrate capable of floating in seawater to obtain seaweed seed threads capable of floating in seawater; and culturing the seaweed seed threads or the seaweed seed threads capable of floating in seawater obtained by cultivating the seaweed seed threads while floating them in flowing seawater in a culture device.

2. A manufacturing method as described in claim 1, wherein the filamentous adhesion substrate has a diameter of 5 mm or less and / or a length of 10 cm or less.

3. A method for cultivating wakame seaweed, comprising the steps of: attaching wakame seaweed seed threads bearing young wakame seaweed sporophytes obtained by the manufacturing method according to claim 1 or 2 to a support; and installing the support obtained in the above step in the sea.

4. A wakame seed thread or wakame seed thread for use in floating culture, which is composed of a filamentous adhesion substrate capable of floating in seawater (excluding the case where the outer periphery of a filamentous core material treated with an aquaculture agent is covered with a foam material containing a mixture of interconnected and independent air bubbles) and wakame spores attached to said substrate, or a wakame seed thread composed of a filamentous adhesion substrate capable of floating in seawater and wakame juvenile sporophytes attached to said substrate.

5. A wakame seed thread composed of a thread-like attachment substrate having a diameter of 5 mm or less that can float in seawater and wakame spores attached to the substrate, or a wakame seed thread composed of a thread-like attachment substrate that can float in seawater and wakame juvenile sporophytes attached to the substrate, which is for use in floating culture.

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