JP2019202978A - Nematode repellant containing asteraceae plant extract as active ingredient - Google Patents

Abstract

To provide a nematode repellant that is excellent in sustained-release of an active ingredient and exhibits a high control effect persistently.SOLUTION: A nematode repellant is composed of a porous body containing agar and Asteraceae plant extract.SELECTED DRAWING: None

Description

  The present invention relates to a nematode repellent containing an Asteraceae plant extract as an active ingredient.

Soil supports plants and is essential for the growth of plants, such as a source of water and nutrients, and a source of storage, but plant parasitic nematodes, bacteria and fungi that cause diseases by infesting and infecting plants There are many other pests.
Plant parasitic nematodes parasitize the roots of the plant, and take up the nutrients absorbed by the plant to grow and multiply, thereby inhibiting the growth of the plant. There are many types of plant parasitic nematodes, but the damage of root-knot nematodes, nepheles nematodes, and cyst nematodes is great. In particular, root-knot nematodes can infest more than 700 types of plants and form one of the most harmful pests that cause significant yield loss and death in a wide range of crops by forming a hump on the parasitic roots and inhibiting nutrient absorption. It is.

Soil disinfection using a fumigant is the most common method for controlling pests that inhabit the soil, but it also has a great impact on the soil ecosystem because it also controls useful organisms. In addition, there is a problem that individuals that live in the deep layer or individuals that have resistance cannot be controlled, and a drug leaks from the surface of the ground, exposing workers and residents in the vicinity. Although a method of spraying chemical pesticides on the soil has also been carried out, pest control that is concentrated on chemical pesticides is not preferable due to environmental impact and food safety concerns.
In addition, methods such as injecting hot water or heating the soil by covering the soil surface with vinyl, methods of reducing the oxygen concentration in the soil by watering after mixing organic substances and covering with vinyl, etc. However, there are problems such as requiring large-scale processing and special equipment, a heavy work load, and limited planting opportunities.

  Plants and pests continue to evolve while struggling to acquire and overcome countermeasures, and some plants have significant resistance to pests. For example, the present inventors have found a powerful anti-nematode action in an extract of Asteraceae plants such as Ayuyusendangusa, and transplanted after immersing plant roots and seeds in a control agent containing the extract Have proposed a method of irrigating a control agent in soil (Patent Document 1).

  Even if these conventional control methods are applied, it is difficult to completely remove pests from the soil. Most plant parasitic nematodes are as small as 1 mm in length, and bacteria and fungi are as small as a few micrometers. They are carried by soil, rainwater, etc. attached to farmer's shoes and agricultural machinery tires. End up. Therefore, in order to prevent agricultural damage caused by nematodes, regular control is necessary regardless of the occurrence of occurrence, and the burden on farmers is large.

Japanese Patent No. 4528982

  This invention makes it a subject to provide the nematode repellent which is easy to apply and exhibits a high control effect continuously.

Means for solving the problems of the present invention are as follows.
1. A nematode repellent characterized by comprising a porous body containing agar and an Asteraceae plant extract.
2. 1. The compounding amount (dry weight) of the Asteraceae plant extract with respect to 100 parts by weight (dry weight) of the agar is 50 parts by weight or more and 1000 parts by weight or less. Nematode repellent described in 1.
3. 1. The Asteraceae plant extract is Ayuyukisendanusa extract Or 2. Nematode repellent described in 1.

The nematode repellent of the present invention only needs to be placed on the soil, mixed, etc., and is easy to apply. The nematode repellent of the present invention can exert its nematode repellent effect continuously because the active ingredient diffuses into the soil little by little by irrigation or rainwater. Since the nematode repellent of the present invention can exert its control effect continuously, it is not necessary to spray agricultural chemicals regularly, and the amount of agricultural chemicals used and the work load can be reduced. Moreover, the balance of immediate effect and sustainability can be adjusted by the compounding amount of the Asteraceae plant extract.
Asteraceae plant extracts act only on plant parasitic nematodes that are harmful to plants, not on autoactive nematodes. Therefore, the nematode repellent of the present invention has little influence on the soil ecosystem and can prevent a decrease in soil vitality due to a decrease in beneficial microorganisms in the soil.
Since the nematode repellent of the present invention is composed mainly of naturally-derived materials, both agar and asteraceae plant extracts, it has little impact on the environment.

  The nematode repellent of the present invention is characterized by comprising a porous body containing agar and an Asteraceae plant extract.

"Agar"
Agar is a polysaccharide contained in red algae such as gonogori, amakusa, and buckwheat, and is mainly composed of agarose and agaropectin. Agar is soluble in hot water and gels when an aqueous solution of hot water is cooled.
In the present invention, as the agar, stick agar, yarn agar, powder agar, powdered agar, etc. can be used without particular limitation. Moreover, it can also be used individually or in mixture of 2 or more types of agar.

"Asteraceae extract"
The asteraceae plant for obtaining an extract that acts as an active ingredient in the present invention is not particularly limited as long as the extract has a controlling effect on pests that inhabit the soil. Can do. Specific examples include asteraceae plants selected from the genus Sendangusa, the genus Himejoon, the genus Artemisia, and the genus Achillinaceae. Plants belonging to the genus Sendangsa include Kosendungusa (Bidens pilosa L.) and its varieties or varieties. Specific examples of the varieties include Abyssendungsa (Bidens pilosa. Var. Radiata Scherff.) L. var. Radiata Sch. Bip.), Etc., and examples of the varieties include Bidens pilosa L. var. Radiata Scherff. F. Decumbens Scherff. Examples of the plant belonging to the genus Himejoon include Himejoon (Stenactis annuus (L.) Cass.). Examples of plants belonging to the genus Artemisia include echinoderm (Erigeron bonariensis L.), giant echinoderm (Erigeron sumatrensis Retz.) And the like. Examples of the genus Akinokirinso include Solidago altissima L. and the like. Among the above-mentioned Asteraceae plants, Awayukisendangusa, Tachiawayukisendangusa, Hiawayukisendangusa, Himejoon, Giant peony, and Aedes albaensis are particularly preferable. An extract of the Asteraceae plant may be used alone, or two or more extracts may be mixed and used.

  As an extract, the extract extracted using the solvent or the solid content obtained by drying the extract can be used. As a method for obtaining an extract from the above Asteraceae plants, any method for obtaining an extract from a plant can be used. For example, after cutting various parts (flowers, leaves, stems, roots or whole grasses, preferably whole grass parts excluding roots, more preferably leaves) of raw or dried asteraceae plants, An aqueous solvent such as a mixed solution with alcohol is added about 5 to 250 times the mass of the Asteraceae plant, extraction is performed for about 10 minutes to several days from room temperature to the boiling point of the solvent, and filtration is performed to obtain an extract Can be mentioned.

The asteraceae plant extract used in the present invention acts only on plant parasitic nematodes that are harmful to plants, and has no or very little effect on autoactive nematodes. This selective action is a very advantageous attribute that Asteraceae plants gained in the course of evolution while fighting plant parasitic nematodes.
Specifically, from the family Tylenchida (Meloidogynidae), Meloidogyne arenaria (Neal) Chitwood, Meloidogyne incognita Kofoid et White, Meloidogyne hapla (Meloidogyne hapla) Meloidogyne java (Treub) Chitwood) and other species, Pratylenchus (Pimmerylenchus coffeae (Zimmermann) Filipjev & Schuurmans Stekhoven), Kittanegus penetrans (Cobb) Fiurjev Negrass nematodes such as Pratylenchus loosi Loof, Heterodera family, potato cyst nematode (Globodera rostochiensis (Wollenweber) Mulvey & Stone), okabo cyst nematode (Heterodera elachista Ohshima), soybean Cyst nematodes such as preparative nematode (Heterodera glycines Ichinohe), having preferably Meloidogyne incognita, soybean cyst nematode, motion inhibition southern Negu Sare nematode, lethality, hatching inhibition, chemical nematocidal action of repelling like.

  Autoactive nematodes can be categorized into bacteriophages, filamentous fungi and carnivorous nematodes, which are responsible for the degradation of organic matter and material circulation in the soil and play an important role in enriching the soil ecosystem. . Asteraceae plant extracts include Plectus sp., Cephalobus sp., Rhabditis sp., Panagrolaimus sp., Etc. It does not show chemical anti-nematode action on self-active nematodes.

  The asteraceae plant extract used in the present invention does not have an allelopathy action that inhibits the growth of plants other than the asteraceae plants, and therefore the cultivated plant species is not limited to asteraceae plants. For example, besides asteraceae such as lettuce, celery, burdock, cucumber, melon, watermelon, pumpkin and other cucurbitaceae, eggplant, tomato, pepper, pepper, potato and other solanaceae, soybean, kidney bean and other legumes, carrot It can be used for cultivation of various plants that are damaged by the above-mentioned pests, such as the celery family and the sweet potato family such as sweet potato.

`` Nematode repellent ''
The nematode repellent of the present invention consists of a porous body of agar and an Asteraceae plant extract. The compounding amount (dry weight) of the Asteraceae plant extract with respect to 100 parts by weight (dry weight) of agar is preferably 50 parts by weight or more and 1000 parts by weight or less. When the compounding amount of the Asteraceae plant extract with respect to 100 parts by weight of agar is less than 50 parts by weight, the amount of active ingredients decreases, and the repellent action and persistence on nematodes are reduced. When the compounding amount of the Asteraceae extract with respect to 100 parts by weight of agar exceeds 1000 parts by weight, it becomes difficult to obtain a uniform porous body, and when the obtained porous body is brittle and cut into an appropriate size It is easy to break apart. The compounding ratio (dry weight) of agar and asteraceae plant extract is high when the asteraceae plant extract is more than 300 parts by weight and less than 500 parts by weight with respect to 100 parts by weight of agar. Excellent immediate effect. Moreover, it is excellent in sustainability when the Asteraceae plant extract is 100 parts by weight or more and 300 parts by weight or less. The detailed cause of the difference in the release properties is unknown, but it is assumed that there is a difference in the structure inside the porous body.

  The nematode repellent of the present invention is combined with a chemical such as an insecticide, acaricide, nematicide, fungicide, herbicide, plant growth regulator, fertilizer, etc., as long as it does not inhibit moldability. be able to. In particular, by combining with pesticides that have a pest control action against pests such as insecticides, acaricides, nematicides, fungicides, etc., reduce agricultural damage not only by nematodes but also by other pests be able to. These agents can be used alone or in combination of two or more. In addition to the chemicals, additives such as stabilizers, coloring agents, extenders, ultraviolet absorbers, antioxidants, anti-corruption agents and the like can be added to the nematode repellent of the present invention.

  The nematode repellent of the present invention can be applied by placing, mixing, etc. on soil. Since the nematode repellent of the present invention is composed of a porous body having agar as the main skeleton, it can contain water inside, and the asteraceae plant extract is dissolved in this water and slowly diffuses into the surrounding soil. It exhibits anti-nematode ability. As described above, the nematode repellent of the present invention can control its release by the weight ratio of agar and asteraceae plant extract. The nematode repellent of the present invention can be applied to those having different weight ratios of agar and asteraceae extract, if necessary, and nematodes having different weight ratios of agar and asteraceae extract. A repellent can also be used in combination.

"Production method"
The porous body containing agar and asteraceae plant extract, which is the nematode repellent of the present invention, was obtained, for example, by drying a asteraceae plant extract or asteraceae plant extract into a hot water aqueous solution of agar. It can be produced by a method in which one or both of the solid components are mixed, uniformly dissolved or dispersed, cooled, gelled, and dried. Although the density | concentration of the hot water aqueous solution of agar is not restrict | limited in particular, For example, they are 1% or more and 15% or less. The higher the agar concentration, the more difficult it is to dissolve uniformly.

  The drying method is not particularly limited, and methods such as freeze drying, vacuum drying, and high temperature drying can be used. Among these, lyophilization is preferable because a porous body having a small amount of water and fine pores can be obtained.

  Next, the present invention will be described more specifically based on examples, but the present invention is not limited to these examples.

-Asteraceae plant extract Awayukisendangusa dried at 100 ° C for 24 hours using a dry heat sterilizer was cut with scissors and then finely pulverized with a mixer. 250 g of this pulverized product was placed in a 2 L beaker, 1250 ml of distilled water was added and mixed well, and a wrap film was further covered with aluminum foil to prevent evaporation. After boiling this mixed liquid for 30 minutes, it cooled to room temperature (25 degreeC), and squeezed with the cotton cloth, and the asteraceae plant extract was obtained. This extract was vacuum-dried to obtain a powdery Asteraceae plant extract.

“Experiment 1”
20 g of a asteraceae plant extract was added to 100 g of a 10% strength agar aqueous solution to obtain a molded product of resin: repellent = 1: 2.
30 g of a asteraceae plant extract was added to 100 g of a 20% aqueous solution of PVA to obtain a molded product of resin: repellent = 2: 3.
100 g of Yoshino kuzu powder was dissolved in 400 ml of water, 100 g was taken, 25 g of Asteraceae plant extract was added, and a molded product of resin: repellent = 1: 1 was obtained.
10 g of an Asteraceae plant extract was added to 100 g of a 10% gelatin aqueous solution to obtain a molded article of resin: repellent 1: 1.
Although 10 g of Asteraceae plant extract was added to 100 g of 10% aqueous pectin solution, it did not harden and a molded product could not be obtained.
To a place where 10 g of gelatin was dissolved in 60 g of water, 5 g of pectin powder and 10 g of Asteraceae plant extract were added, dissolved by heating, and then cooled and gelled to obtain a molded product of resin: repellent = 3: 2. .

The molded body was evaluated as follows. The results are shown in Table 1.
(Gelation)
Gelation was judged from the visual and tactile sensations of the molded body.
(Drying)
The gelled compact is dried, and the appearance after drying is visually determined.
(Stability)
The molded body that was cooled and gelled was heated to 40 ° C.
○: Maintained gel state ×: Melted and fluid

"Experiment 2"
From the gelling agents used in Experiment 1 above, agar and PVA are selected from the viewpoints of moldability and stability, and a porous material is produced from these and an Asteraceae plant extract, and a tomato cultivation test is conducted. It was.

-Porous material 10g, 20g of Asteraceae plant extract (dried product) is added to 100g of 10% agar aqueous solution heated to 100 ° C, poured into a predetermined mold, cooled, cut into 1cm square, and freeze-dried. The porous body of 1: 1 and 1: 2 was obtained.
To 100 g of 10% PVA aqueous solution heated to 90 ° C., 10 g or 20 g of Asteraceae plant extract (dried product) is added, poured into a predetermined mold and cooled to obtain a molded article having a composition of 1: 1, 1: 2. It was. Thereafter, freeze-drying was performed to obtain a porous body, which was cut into 1 cm square.

・ Meloidogyne incognita Kofoid et White
Put a paper wiper (made by Nippon Paper Crecia Co., Ltd., trade name “Kimwipe”) in a petri dish containing sterilized water, and place an eggplant collected from the original parasitic eggplant of Yonagi Nishihara, Uruma City, Nakagami-gun, Okinawa. The second stage larvae hatched in an incubator were collected with a Pasteur pipette, inoculated into a cherry tomato “Chibikko” (Lycopersicum esculentum Mill.), And the second stage larvae of the sweet potato nematode were used.

-Tomato cultivation Commercially available Shimajiri merge (trade name: Shimajiri red clay, manufactured by Green Earth Sangyo Co., Ltd.) and vermiculite (manufactured by Nittai Co., Ltd.) were mixed at a ratio of 4: 1 and sterilized. Organic fertilizer (trade name: Minori, manufactured by Minori Co., Ltd.) was mixed as basic fertilizer in terms of 3 t per 10a to obtain a test soil. The 1 / 10,000a Wagner pot was filled with the test soil, sufficiently irrigated and allowed to stand for one week.
Polypot No. 6 (Product name: TO polypot round type, capacity 360cc, manufactured by Tokai Kasei Co., Ltd.) planted the root pot of mini tomato seedling ("Lycopersicum esculentum Mill.") In the above Wagner pot The soil was inoculated with 10 ml of a sweet potato nematode suspension (1,000 heads / 10 ml) using a 10 ml measuring pipette.

Two porous bodies having a composition of 1: 1 and one porous body having a composition of 1: 2 were installed in the stock company.
As a control, a porous body that does not contain an extract of Asteraceae plant, a nematicide phosthiazeate granule (trade name: Nematrine Ace Granule, manufactured by Ishihara Sangyo Co., Ltd.) 15 kg per 10a What was mixed in terms of soil was used as soil, with no porous material installed, with only nematode inoculation, and with no porous material installed and with root-knot nematode inoculation. The number of each sample was six.

  Forty days after planting, after growing in the greenhouse of the University of the Ryukyus, Faculty of Agriculture, Nishihara-cho, Nakagami-gun, Okinawa Prefecture, the growth volume (plant height, root length, above-ground weight and root weight), root-kump degree, soil nematode density Were counted. The growth amount of the plant body was measured for all six samples according to a conventional method. Counting the root-knot index and soil nematode density was performed according to the following method. The measurement results are shown in Table 2.

-Root Hump Degree According to the following evaluation criteria, the degree of root hump was evaluated in a total of 9 stages, 5 stages from 0 to 4 and 4 stages of each intermediate value, and the average value of 6 samples was calculated.
Evaluation Content 0: No hump.
1: A slight hump is observed, but the damage is not noticeable.
2: A gall is recognized at first glance. There are few large or continuous root bumps.
3: Many large and small root bumps are observed. Although thickened roots are also seen, they are less than 50% of the total root area.
4: Many roots are full of roots and thick.

-Soil nematode density About 100 g of soil around each root was taken from 6 samples and mixed. 20 g of the mixed soil was weighed, and the number of nematodes was counted by the Baleman funnel method. Separation was performed at 25 ° C. for 72 hours. Counting was repeated 3 times using different soils.

Neither agar nor PVA alone had the effect of suppressing (controlling) the gallbladder.
A porous body using agar showed anti-nematode properties, and in particular, a porous body having a composition of 1: 2 showed an effect equivalent to that of a commercially available nematicide. As for PVA, a porous material having a composition of 1: 2 showed a control effect, but its root-knot suppression effect was lower than that of agar.

“Experiment 3”
In the same manner as in Experiment 2 above, porous bodies having a composition of 1: 2, 1: 4, 1: 8 were obtained from agar and Asteraceae extract. Moreover, the 1 cm square gel was obtained, without freeze-drying the molded object of composition 1: 2.

  The porous body or gel was immersed in 10 mL of distilled water, all the water was collected after a predetermined time, and 10 mL of fresh distilled water was added. The sugar content of the collected water was measured with a sugar content meter (manufactured by Atago Co., Ltd., pocket sugar content / concentration meter PAL-1). The results are shown in Table 3.

All the porous bodies were excellent in the release property of the Asteraceae plant extract. On the other hand, the gel which was not freeze-dried was inferior in the release property of the Asteraceae plant extract. This is presumably because the exchange of water did not proceed between the inside and outside of the gel.
The greater the amount of the Asteraceae plant extract, the better the initial (after 2 hours) release, but after 23 hours, the composition 1: 2 released more Asteraceae plant extract.
From this, it can be confirmed that a nematode repellent superior in immediate effect can be obtained by increasing the compounding amount of the Asteraceae plant extract, and excellent in sustainability by reducing the compounding amount of the Asteraceae plant extract. It was.

Claims (3)

  A nematode repellent characterized by comprising a porous body containing agar and an Asteraceae plant extract.   The nematode repellent according to claim 1, wherein the compounding amount (dry weight) of the Asteraceae plant extract with respect to 100 parts by weight (dry weight) of the agar is 50 parts by weight or more and 1000 parts by weight or less.   The nematode repellent according to claim 1 or 2, wherein the Asteraceae plant extract is an Ayuyukisendanusa extract.