JPH0662690A - Production of seed of seaweed of brown algae - Google Patents

Abstract

PURPOSE:To promote the growth of a seed and prevent disease-affected marine bacteria from breeding by specifying the intensity and irradiation time of ultraviolet rays for irradiating the initial sporophore after the fertilization of gametophytes of seaweeds of brown algae. CONSTITUTION:A planospore sticking to a thread of a seed organ is germinated and grown into gametophytes of a female and a male to further carry out the fertilization and a sporophore is formed. The sporophore in the initial fertilization is then irradiated with ultraviolet rays at 50-500muW/cm<2> intensity for 5-30sec. The sporophore is irradiated with the ultraviolet rays by taking out the seed organ in which the sporophore is formed from a culture tank, lighting ultraviolet lamps arranged at an interval so as to irradiate the sporophore therewith at 50-500muW/cm<2> intensity and irradiating the sporophore for 5-30sec. When the resultant irradiated sporophore subjected to the treatment is cultured to produce a seed, the growth of the seed can be promoted to prevent disease and injury from occurring.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing brown algae seaweeds such as seaweed and kelp, which promotes the growth of seedlings by irradiating the early sporophytes of the brown algae seaweeds with ultraviolet rays to the early stage. The present invention relates to a method for shortening the seedling process.

[0002]

2. Description of the Related Art Seaweeds of the order Astragalus, such as seaweed, kelp, black chrome, lamme, Honda straw, red mok, are edible,
In recent years, aquaculture business such as seedlings and large-scale culture has been attempted because it is extremely useful for underwater forest creation business and marine environment purification business, including for feed. Seaweeds of the order Astragalus have a so-called kelp-type life in which the sporophyte generation (asexual generation) and the gametophyte generation (sexual generation) alternate. Meiosis occurs when zoospores form on the sporophyte. The zoospores released from the mature mother algae float in the sea and adhere to the seabed or the surface of aquaculture threads, germinate and grow into female and male gametophytes, and fertilization takes place to become juveniles (spore bodies). , Then grows and grows into seaweed such as so called kelp.

Among these brown algae seaweeds of the order Astragalus, especially kelp and wakame seaweed have been conventionally cultivated, and at present, forcible cultivation techniques are carried out in about 4 to 10 months from seedling collection to cultivation and incorporation. Is being developed. In forced-cultivation of kelp, zoospores are taken out from natural mother algae (2nd year) and attached to a prescribed seedling thread (seedling), and then this is supplied to sterile seawater or filtered seawater with nutrients such as phosphoric acid and nitrogen. It is put in the added culture solution, and indoor culture is performed up to a juvenile with a leaf length of 3 to 5 mm, and then it is taken out into the sea and cultured. In the forced cultivation, seedlings are collected from late August to early September when the natural leaf body that is the mother alga matures, indoor culture is carried out to the juveniles for about 45 to 60 days, and they are released in the middle of October. 7-1
Temporarily planted on day 0 to make seedlings.

[0004]

As described above, conventionally, zoospores collected from mother algae are attached to seedling threads, which are then cultivated with an artificial nutrient salt using sterilized or filtered seawater to grow long seedlings. After that, he was producing seedlings. For this reason, there is a problem that the culture efficiency of seedling production is poor. Further, in the cultivation of kelp and seaweed, there is a possibility that marine bacteria (Alterromonas genus) may cause red spot disease, and germs such as sporangial hole rot may cause marine bacterial diseases. In order to prevent these diseases, conventionally, chlorine-based disinfectant treatment has been performed, or although it is not preferable for the growth of seedlings, measures such as limiting nitrogen nutrients in the culture solution in indoor culture are taken. However, the countermeasures against these diseases also delay the seedling production period.

The present invention has been made in view of the above circumstances, and is capable of promoting the growth of seedlings and preventing the growth of diseased marine bacteria to produce healthy seedlings in a short period of time. The purpose is to provide a method for producing seedlings of seaweed.

[0006]

The method of producing seedlings of brown algae seaweed according to the present invention is characterized in that the initial sporophytes of the brown algae seaweed are irradiated with 5 to 500 μW / cm ² of ultraviolet light having an intensity of 50 to 500 μW / cm ^2.
It was irradiated for 30 seconds, and this was cultivated to produce seedlings, thereby achieving the above-mentioned object.

[0007]

[Action] In the early sporophyte after gametophyte fertilization of brown algae seaweed,
By irradiating with ultraviolet rays having an intensity of 50 to 500 μW / cm ² for 5 to 30 seconds and culturing this, the growth of sporophytes is promoted as compared with non-irradiation, and the culture period for obtaining seedlings of a predetermined size is increased. It is cut in half. Further, the irradiation of ultraviolet rays makes it possible to prevent the propagation of disease marine bacteria.

[0008]

EXAMPLES As an example of the method of the present invention, the case where the present invention is applied to the cultivation of a typical kelp of the brown algae seaweed will be described below. FIG. 1 is a diagram explaining a seedling and seedling process of kelp according to the present invention. In the production of kelp, first, zoospores are taken out from the mother alga and the zoospores are allowed to settle in a predetermined seedling collecting device (seedling). In this seedling, the mature mother algae is placed in an aquarium, the zoospores are released into the aquarium, the mother algae is then removed from the aquarium, and the seawater containing the zoospores in the bath is filtered with a cloth, etc. It is carried out by diluting the zoospores by allowing them to stand for about one day by placing a seedling collecting device in this solution. As the seed-collecting device, a device in which a seedling thread of several hundred m is wound around a frame is preferably used.

The seedling device (seedling device) on which the zoospores have settled is placed in another water tank and cultured indoors. The culture solution used here is a culture solution obtained by adding nutrients such as phosphates and nitrogen salts to filtered seawater or sterilized seawater, for example, Propasoli ESI.
Nutrient seawater or the like is preferably used. In addition, the culture conditions were irradiation of 2000-6000 lx fluorescent light (day length 12-
It is desirable to do it in about 16 hours.

The zoospores attached to the threads of the seedlings germinate and grow into gametophyte of female and male, and then fertilization is performed to form sporophytes. In the present invention, ultraviolet rays having an intensity of 50 to 500 μW / cm ² are added to the sporophytes in the early stage after fertilization for 5 to 3 times.
Irradiate for 0 seconds. To irradiate the sporophyte with ultraviolet rays, take out the seedling device in which the sporophyte is formed from the culture tank and
It is carried out by turning on ultraviolet lamps arranged at intervals such that ultraviolet rays having an intensity of 0 μW / cm ² are irradiated and irradiating for 5 to 30 seconds. Ultraviolet light having a wavelength of around 234 nm is suitable as the wavelength of the ultraviolet rays to be applied.

In the ultraviolet irradiation of the spores, if the ultraviolet intensity is less than 50 μW / cm ² , the effects of promoting the growth of the spores and suppressing the propagation of disease marine bacteria cannot be sufficiently obtained.
There is no difference from those that do not irradiate with ultraviolet rays. If the UV intensity is higher than 500 μW / cm ² , the damage to the sporophytes due to the UV rays will be large and, on the contrary, the growth of the sporophytes will be inhibited. If the UV irradiation time is shorter than 5 seconds, the effect of promoting the growth of sporophytes and the growth of disease marine bacteria cannot be sufficiently obtained, and there is no difference from the case where the UV irradiation is not performed, and the UV irradiation time is longer than 30 seconds. It will inhibit the growth of sporophytes. Ultraviolet rays with an intensity of 50 to 500 μW / cm ² were applied to the sporophytes in the early stage after fertilization of gametophyte for 5 to 3 times.
By irradiating for 0 seconds, the growth of sporophytes is promoted as compared with non-irradiation, and the culture period for obtaining seedlings of a predetermined size is shortened to about half. Further, the irradiation of ultraviolet rays makes it possible to prevent the propagation of disease marine bacteria.

The sporophyte irradiated with ultraviolet rays under the above conditions is
It is placed in a culture tank and cultivated, and grows into a young body (seedling) in a short period of time compared to the unirradiated one. When the seedling becomes a certain size, that is, a juvenile with a leaf length of 3 to 5 mm, the thread of the seed and seedling device is removed from the frame body, hung on the raft of the ocean, temporarily planted in the open sea, and further transferred to the main training. Harvested after several months of culture.

The present invention is applied to the initial sporophyte after gametophyte fertilization in the culture of brown algae such as kelp and seaweed, and the amount of 50 to 500
By irradiating with ultraviolet rays with an intensity of μW / cm ² for 5 to 30 seconds and culturing this to produce seedlings, it is possible to promote the growth of seedlings as compared with the conventional method which does not irradiate with ultraviolet rays, so that the seedlings can be grown for a short period of time. Large seedlings can be produced by culture, and the seedling period can be shortened. Moreover, diseased marine bacteria can be sterilized by ultraviolet irradiation, and the occurrence of disease can be prevented. As a result, the step of sterilizing seeds and seedlings with a conventional chemical bactericide can be omitted, and the bactericidal effect can be enhanced as compared with the chemical bactericide. Furthermore, in the conventional method, the nutrient components such as nitrogen sources were reduced in order to suppress the reproduction of the diseased bacteria, but in the method of the present invention, the diseased bacteria can be sterilized by ultraviolet irradiation, so that the diseased bacteria can be sterilized under nutritional conditions sufficient for development. Can be cultured without damage. Therefore, according to the present invention,
Healthy seedlings can be produced by culturing for a short period of time, the seedling production turnover rate can be increased, and the culturing cost can be reduced.
Incidentally, the present invention can be applied not only to kelp but also to seaweeds of brown algae kelp order such as wakame, kurome, arame, hondawara, and red moku, and the same effect as in the case of kelp can be obtained. .

(Experimental Example) An ultraviolet irradiation experiment in mackerel culture as a typical example of seaweed of the order Astragalus of the brown alga will be described. Put the mature mother alga of the second year in sterilized seawater to release the zoospores, and after filtering and diluting, put a seeder around which seed threads are wound in the seed solution containing the zoospores, and use the gametophytes as seed threads. Attached.
This seedling was transferred to a culture tank containing ESI nutrient seawater, and after fertilization was confirmed to form sporophytes, a wavelength of 234.7
UV light having a wavelength of 400 nm was irradiated at an intensity of 400 μW / cm ² for 5 to 30 seconds, and the cells were further cultured. The results are shown in Table 1.

[0015]

[Table 1]

As can be seen from Table 1, ultraviolet rays of 5 to 20
In the case of culturing with second irradiation, the growth of seedlings was faster than that of non-irradiation, and seedlings could be produced in about half the number of culture days as compared with non-irradiation. On the other hand, the one irradiated with ultraviolet rays for 30 seconds showed growth inhibition. In addition, the seedlings that were irradiated with ultraviolet rays did not show any disease, and healthy seedlings could be produced.

(Experimental Example 2) 50-500 μW / c at the time of producing a seedling of a male and female cross-bred strain of Rhus unikonbu and macombi
By irradiating with ultraviolet rays of m ² intensity for 5 to 30 seconds,
A germination promoting effect was observed.

[0018]

INDUSTRIAL APPLICABILITY As described above, according to the present invention, in the culture of brown algae such as kelp and the like, the early spore bodies after gametophyte fertilization are exposed to ultraviolet rays of 50 to 500 μW / cm ² intensity.
By irradiating for ~ 30 seconds and culturing the seeds to produce seedlings, it is possible to promote the growth of seedlings as compared with the conventional method in which ultraviolet rays are not irradiated, and it is possible to produce large seedlings by culturing for a short period of time. Therefore, the seedling period can be shortened. Moreover, diseased marine bacteria can be sterilized by ultraviolet irradiation, and the occurrence of disease can be prevented. As a result, the step of sterilizing seeds and seedlings with a conventional chemical bactericide can be omitted, and the bactericidal effect can be enhanced as compared with the chemical bactericide.
Furthermore, in the conventional method, the nutrient components such as nitrogen sources were reduced in order to suppress the reproduction of the diseased bacteria, but in the method of the present invention, the diseased bacteria can be sterilized by ultraviolet irradiation, so that the diseased bacteria can be sterilized under nutritional conditions sufficient for development. Can be cultured without damage. Therefore, according to the present invention, healthy seedlings can be produced by short-term culture, the seedling production turnover rate can be increased, and the culture cost can be reduced.

[Brief description of drawings]

FIG. 1 is a flow chart for explaining an example of a seedling production method for brown algae seaweed according to the present invention.

Claims (1)

[Claims] 1. An ultraviolet ray having an intensity of 50 to 500 μW / cm ² is applied to the early sporophytes after fertilization of the gametophyte of brown algae seaweed to 5 to 5 μW / cm ^2.
A method for producing seeds of brown algae, which comprises irradiating for 30 seconds and culturing the seeds to produce seeds.