JPS5810509A - Agent for controlling blight of edible seaweed and method for using the same - Google Patents

Abstract

PURPOSE:To provide an agent for controlling the blight of edible seaweeds, and containing a water-soluble alkaline inorganic compound such as NaOH, KOH, etc. preferably in combination with a water-soluble compound of Cu, Zn, Al, etc. CONSTITUTION:The objective agent contains (A) one or more water-soluble inorganic compounds exhibiting alkaline state in water (e.g. sodium carbonate, ammonia, etc.) as an active component, and if necessary, (B) at least one water- soluble compound of a metal selected from Cu, Zn, Al, Ga, Ge, Sn and Pb (e.g. copper sulfate, zinc nitrate, etc.). The agent is added to sea water, and the seaweed to be treated is immersed in or sprayed with the sea water. EFFECT:Especially high effect to the wasting disease caused by the adhesion of miscellaneous algae can be attained by the combined use of the compounds of Cu, Zn, etc.

Description

[Detailed description of the invention] The present invention relates to a disease control agent for edible seaweed and its use.

The growth of edible seaweeds, especially red algae such as Norifolia and Norifolia, is inhibited by pathological bacteria and microorganisms. Typical diseases of nori include pot-shaped fungal disease and red rot due to intracellular parasitism of pathological bacteria, as well as filamentous bacterial enthesis and dota rot due to adhesion of bacteria and algae to the leaf surface. etc. These diseases occur almost every year and cause great damage to seaweed aquaculture.

Conventionally, the following methods have been used to control these diseases. In other words, for pot-shaped fungal disease, early plucking or removal of diseased leaves (no effective chemotherapy is known yet), and for red rot, prolonging the drying time, freezing treatment, and acid treatment. Treatment with seawater or high-salinity seawater, and for stain rot, drying, freezing, or treatment with acidic seawater are performed. However, at present, no countermeasures against filamentous bacterial adhesion have yet been developed. These diseases often occur as complications, and one disease may spread to another.

The present inventor has conducted various research on a control agent that can effectively control various diseases of edible seaweed, does not cause environmental pollution, and does not have any adverse effects such as toxicity on aquatic organisms. Completed the invention.

The present invention is an edible seaweed disease control agent characterized by containing a water-soluble inorganic compound exhibiting alkalinity as an active ingredient.

Furthermore, the present invention is a method for controlling diseases of edible seaweed by adding this control agent to seawater and immersing the seaweed in this seawater or spraying the seaweed with this seawater.

The active substances used in the present invention are water-soluble and alkaline inorganic compounds, such as alkali metal hydroxides or carbonates, such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, These include sodium hydrogen carbonate, potassium hydrogen carbonate, and ammonia.

The pesticidal agent of the present invention may consist only of one or more of the above-mentioned compound agents, but may further contain Cu, Zn,
A water-soluble compound (B) of at least one metal selected from the group consisting of Al, Ga, Ge, Sn and pb, such as a halide, preferably a chloride, sulfate, nitrate,
It is preferable to contain a phosphate or the like. When these substances are used in combination, a particularly high effect can be obtained against the rot caused by algae attachment.

In addition, the present control agent can also be blended with inorganic and organic fertilizers, vitamins, and others commonly used for the growth of seaweed. Inorganic fertilizers include, for example, Na1, Mg
, Ca, B, I, Mg1Fe, Co, Ni, Zn,
In addition to inorganic compounds of elements such as Mo, organic fertilizers include urea, amino acids, sugars, nucleic acids, nucleic acid bases, vitamins, etc., and fertilizers based on seaweed hydrolysates (JP-A-55-149567). (see specification). These fertilizer substances are used in appropriate combinations depending on the target seaweed.

It is particularly advantageous to use the disease control agent of the present invention containing fertilizer, since the disease control effect of the present invention and the fertilizer effect can be obtained at the same time. This is because diseased seaweed loses its vitality and its growth is severely inhibited, so restoring vitality and promoting growth with fertilizer will help cure the disease.

The fertilizer-containing disease control agent can be made into a solid preparation by, for example, mixing an alkaline compound (N and optionally a metal compound (B) and fertilizer components in solid form. Aqueous formulations can also be prepared by dissolving or mixing chelating agents such as chelating organic acids such as citric acid, ethylenediaminetetraacetic acid, hydroxyl, etc. to stabilize trace metal ions in the aqueous solution. It is preferable to add ethylenediaminetriacetic acid, salts thereof, and the like.

When using the disease control agent of the present invention, first, the basic principle is added to seawater to prepare alkaline seawater. In this case, the alkaline compound (A) and, if desired, the metal compound (B) can be added to the seawater directly or in the form of an aqueous solution. Next, the seaweed is immersed in the alkaline seawater obtained, or the seaweed is sprayed with this seawater. The pH value of alkaline seawater is generally 9 or more, preferably from 9 to 13 when ammonia is used as the compound (A), and from 10 to 14 when other compounds (A) are used. If the pH value is lower than 9, the desired control effect will hardly be obtained. Spraying is generally done at sunrise, and after a certain period of time has elapsed after spraying,
The treated seaweed is returned to seawater. The immersion time and sunrise time are determined by the type of alkaline compound used and its concentration or pH value in seawater. Metal compounds (
B) is generally used at a concentration of 50-10001) pm.

When used in combination with a fertilizer, the alkaline compound (A) and optionally the metal compound (B) and the fertilizer are added in any order, or the fertilizer formulation prepared as described above is added to seawater. In this case, the amount of compound motive force required to make seawater alkaline is determined primarily by the fertilizer components.

The dipping treatment and the spraying treatment are then carried out in the same manner as described above.

The disease control agent of the present invention is extremely effective against pot-shaped fungal disease, red rot, congealed white rot, filamentous bacterial enthesosis, pot rot and other diseases, and hardly any damage to seaweed is observed. Furthermore, the basic rules are also useful for exterminating miscellaneous algae (diatoms, green laver, etc.).

EXAMPLE An organic liquid fertilizer for seaweed culture having a bactericidal effect according to the present invention is prepared from the following components (in units of J).

Organic fertilizer described in Example 2 of JP-A-53-149567 100 Chelate liquid having the composition shown below 100 Sodium nitrate
1゜Disodium phosphate
5 urea
20L-Leucine
1L-inoleucine 0.
2L-Tyrone 1L-Arginine 0.2Adenine
0.1 glucose
5 sucrose
2 galactose
OA fructose 0.1
Lactose 0.1 salt
3゜EDTA-4Na
25 citric acid
1゜Potassium hydroxide
8゜Sodium hydroxide 120 water
490.2
1000.0 Composition of chelate liquid (unit: s): Copper sulfate 0.25 Zinc nitrate 2.5 Ferric chloride
0.4 cobalt chloride
0.5 manganese chloride
0.5 Nickel chloride 0.7
5 Calcium nitrate 2,5 Magnesium sulfate 2.5 Sodium molybdate 0.6 Boric acid
1. .

Potassium hydroxide 5.0 Potassium iodide 0.75 Citric acid
5, EDTA-4Na
3-hydroxyethylenediamine triacetic acid trisodium 0.5 water
76.
25100.00 Test Example 1 Sodium hydroxide was added to seawater to prepare alkaline seawater exhibiting various pH values. The pH value was measured by a glass electrode method. The pH value of seawater without the addition of sodium hydroxide was 8. In these alkaline seawater, the laver fronds and the laver fronds infested with pot-shaped fungi, red rot fungi, and filamentous bacteria were immersed for a predetermined period of time. In order to examine the resistance of the glue leaves and pathological bacteria to alkaline seawater, the degree of damage to the glue and the amount of bacteria attached were measured by microscopic observation or erythrosin staining (dead cells in the glue are stained) before and after immersion. After immersion, the cells were cultured for an additional 10 days under normal conditions, and the presence or absence of disease progression was investigated.

The samples used were those collected at an outdoor fishing ground. The thallus of each sample was slightly weaker than that of normal cells, and therefore the drug resistance was also reduced.

The results obtained are shown in Tables 1-4.

When similar tests were conducted using potassium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogen carbonate, and potassium hydrogen carbonate instead of sodium hydroxide, almost the same results as in Tables 1 to 4 were obtained, respectively.

Test Example 2 Table 5 shows the results obtained by operating in the same manner as in Test Example 1 using ammonia instead of potassium hydroxide. The symbols in the tables have the same meanings as in Tables 1-4.

Test Example 6 The metals shown in Table 6 were added in the form of chlorides or sulfates to seawater in an amount such that the metal concentration was 5 D C 1 ppm, and then an equimolar amount of EDTA-4Na was added.

The pH value was adjusted to 12 with IJ hydroxide.

In each of the obtained liquids, add 6 pieces of glue with diatoms attached to the surface.
After immersion for 0 minutes, the cells were cultured for 24 hours under normal conditions. The diatom extermination rate was determined from the amount of diatom adhesion before dipping and after culturing. The results are shown in Table 6.

Table 6: Diatom extermination effect of metals, Test Example 4 Using the liquid fertilizer with the bactericidal effect described in the example, a seaweed disease control test was conducted in an outdoor fishing area as follows. A solution diluted 50 times with seawater (pH 12)
) for 40 minutes, or
A twice diluted solution (pH 11) was sprayed on the cracks during drying, and the dried condition was maintained for 2 hours. After immersion or spraying in this manner, normal culture was carried out for 5 days, and the progress of the disease and the growth of the seaweed were examined. The results are shown in Table 7 together with the results without treatment.

Test Example 5 Liquid fertilizer described in Example and 6% water-soluble metal salt added to it
An algae extermination test was conducted at an outdoor fishing area using the additive. After diluting each of the above-mentioned liquid fertilizers 100 times with seawater, the glue cracks with diatoms and green laver attached to them are soaked for 60 minutes, and then normal cultivation is carried out for 5 days. The algae extermination rate was calculated from the amount of algae attached before dipping and after cultivation. The results are shown in Table 8.

Table 8: Test example 6 of the algae-killing effect of metals in field tests The metals shown in Table 9 were added to seawater in the form of chlorides or sulfates at various concentrations, and then EDTA-4Na was added.
The pH value was adjusted to 11 with sodium hydroxide. In each of the obtained solutions, the paste affected by red rot was immersed for 10 minutes, and then cultured for 10 days under normal conditions. The lowest metal concentration at which the number of diseased cells after culturing was reduced to 10% or less compared to that before immersion (the survival of bacteria was almost no longer observed) was determined.

A test was also conducted on pot-shaped fungus-affected glue using the same method (
However, the pH value is 12).

These results are summarized in Table 9.

Claims (1)

[Scope of Claims] 1. An edible seaweed disease control agent, which contains a water-soluble inorganic compound exhibiting alkalinity as an active ingredient. 2. The disease according to claim 1, which contains a water-soluble compound of at least one metal selected from the group consisting of copper, zinc, aluminum, gallium, germanium, tin, and lead. Pesticide. 6. A disease control agent for edible seaweed containing an alkaline water-soluble inorganic compound as an active ingredient is added to seawater, and the seaweed is immersed in this seawater or the seaweed is sprayed with this seawater. Disease control methods for edible seaweed. 4. Claim 6, characterized in that a water-soluble compound of at least one metal selected from the group consisting of copper, zinc, aluminum, gallium, germanium, tin, and lead is added to seawater. the method of.