JP5063540B2

JP5063540B2 - Method for enhancing resistance to stem blight

Info

Publication number: JP5063540B2
Application number: JP2008235038A
Authority: JP
Inventors: 直樹川村
Original assignee: 晃栄化学工業株式会社
Priority date: 2008-09-12
Filing date: 2008-09-12
Publication date: 2012-10-31
Anticipated expiration: 2028-09-12
Also published as: JP2010065004A

Description

本発明は、茎疫病の技術分野に属する。 The present invention belongs to the technical field of stem blight.

ダイズ茎疫病は病原菌ファイトフィソラソージャ(Phytophthora sojae)によって引き起こされる土壌伝染性の難防除病害で、近年では全国の水田転換畑や不耕起栽培地域を中心に発生が増加傾向にある。茎疫病に罹病した株は枯死して収穫不能となるため、被害額は黒大豆だけでも6.8億円(兵庫県)といわれている。そのため、ダイズ茎疫病の防除技術
が求められている。 Soybean stem blight is a soil-borne, difficult-to-control disease caused by the pathogen Phytophthora sojae. In recent years, the incidence is increasing mainly in paddy field conversion fields and no-tillage cultivation areas throughout the country. Strains that suffer from stem blight have died and cannot be harvested, so the amount of damage is said to be 680 million yen (Hyogo Prefecture) for black soybeans alone. Therefore, there is a demand for techniques for controlling soybean stem blight.

そうした中で、カルシウムが茎疫病に効果があることが、Journal of Phytopathology 153,536-543(2005)に報告されている。
Journal of Phytopathology 153,536-543(2005) Among them, it has been reported in Journal of Phytopathology 153,536-543 (2005) that calcium is effective for stem plague.
Journal of Phytopathology 153,536-543 (2005)

非特許文献１に開示されているとおりカルシウムが茎疫病に効果があることは知られるものの、カルシウムの施用方法、施用時期、好適なカルシウム資材などに関して具体的な提示はなされていない。つまり、農家が実施できるほどに具体化されてはいなかった。 Although it is known that calcium is effective for pesticidal disease as disclosed in Non-Patent Document 1, no specific presentation has been made regarding calcium application method, application time, suitable calcium material, and the like. In other words, it was not materialized enough for farmers to implement.

請求項１記載の茎疫病に対する抵抗性増強方法は、ダイズ又はアズキの苗を、カルシウム濃度が０．４〜１０ｍＭの水溶液に湛水処理した後に定植することを特徴とする。なお、湛水処理とは根鉢部分を水溶液に浸漬する処理である。 Enhancing the resistance method for claim 1 wherein the stem plague, seedlings of soybean or adzuki bean, calcium concentration, characterized in that planting after flooding treatment in an aqueous solution of 0.4 to 10 mM. The submerged treatment is a treatment of immersing the root pot portion in an aqueous solution.

ダイズ又はアズキの苗を湛水処理する水溶液のカルシウム濃度は、０．４〜１０ｍＭであれば本発明の目的すなわち茎疫病に対する抵抗性を増強できる。 If the calcium concentration of the aqueous solution in which soybean or azuki bean seedlings are submerged is 0.4 to 10 mM, the object of the present invention, that is, the resistance against pesticidal diseases can be enhanced .

水溶液中のカルシウムは、水溶性のカルシウム塩である蟻酸カルシウムに由来する構成、すなわち水溶液のカルシウム源を蟻酸カルシウムにするとよい。 Calcium in aqueous solutions is configured derived from calcium formate calcium salts of water soluble, i.e. the calcium source of the aqueous solution may be the calcium formate.

水溶液にしたときのｐＨが中性〜弱酸性であることが植物にとって好ましいので、この条件を考慮すると蟻酸カルシウムが優れている。蟻酸カルシウムは水溶液（１０％溶液）のｐＨ値がほぼ７で、例えば５００〜１００００倍程度に希釈して用いれば事実上中性と言えるのできわめて好適である。 Since it is preferable for plants pH when the water solution is neutral to weakly acidic, calcium formate is better view of this condition. Calcium ants acid at pH value of approximately 7 aqueous solution (10% solution), it is very preferable because it can be said that practically neutral be used by diluting, for example, about 500 to 10,000 times.

前記湛水処理はカルシウムを植物体（ダイズ又はアズキ）に取り込ませるための処理であるから、例えば１〜２日というような短期間では十分な効果を期待できず、請求項２記載のように４日以上にわたっておこなわれるのが好ましい。一方、定植適期との関係もあるから長ければよいというものでもなく、１０日以内が好ましい。 Since the flooding treatment is a process for the incorporation of calcium into plants (soybean or red bean), for example, a short period of time can not be expected to sufficient effect as that 1-2 days, as claimed in claim 2, wherein It is preferably performed over 4 days. On the other hand, there is also a relationship with the optimal planting time, so it is not necessary that it is long, and it is preferably within 10 days.

湛水処理は、できるだけ幼苗期に行うのが好ましく、請求項３記載のように初生葉確認から２日以内に開始されるのが望ましい。特に、請求項４に記載の初生葉確認後直ちに実施するのが望ましい。なお、「初生葉確認後直ちに」というのは、初生葉確認後できるだけ速やかにということであり、具体的には「初生葉を確認したなら当日中に」ということである。 The flooding treatment is preferably performed at the seedling stage as much as possible, and is preferably started within 2 days from the confirmation of the primary leaves as described in claim 3 . In particular, it is desirable to carry out immediately after confirming the primary leaves according to claim 4 . Note that “immediately after confirming the primary leaves” means as soon as possible after confirming the primary leaves, and specifically “when the primary leaves are confirmed, during the day”.

そして、請求項５に記載のように、湛水処理は、初生葉確認後から１週間にわたっておこなわれるのが望ましい。 And as described in Claim 5, it is desirable to perform the flooding treatment for one week after the confirmation of the primary leaves.

次に、本発明の実施例等により発明の実施の形態を説明する。なお、本発明は下記の実施例等に限定されるものではなく、本発明の要旨を逸脱しない範囲でさまざまに実施できることは言うまでもない。
［実施例］
（１）カルシウム資材
本実施例ではカルシウム源として蟻酸カルシウムを使用した。蟻酸カルシウムを希釈して水溶液を調製した場合、そのカルシウム濃度（ｍＭ）と希釈倍率との関係は表１に示す通りである。 Next, embodiments of the present invention will be described based on examples of the present invention. The present invention is not limited to the following examples and the like, and it goes without saying that the present invention can be implemented in various ways without departing from the gist of the present invention.
[Example]
(1) Calcium material In this example, calcium formate was used as a calcium source. When an aqueous solution is prepared by diluting calcium formate, the relationship between the calcium concentration (mM) and the dilution ratio is as shown in Table 1.

（２）瓶培養試験（寒天培地接種法）
試験方法：素寒天培地（０．７％寒天と１．３％ショ糖）に蟻酸カルシウムの水溶液（カルシウム濃度は０．４，４，１０，２０ｍＭ、無処理区は０ｍＭ）を処理後、大豆を播種した。初生葉確認後の大豆の地際部にＰＤＡ培地で７日問培養した菌糸を貼り付け接種した。接種後２０日目まで毎日調査を行った。品種は中生光黒、菌はレースＥ（兵庫）を使用し、含菌培地接種法で評価を行った。
結果：表２の通りとなった。すなわち、接種７日目の発病株率は無処理区５８．５％に対して、蟻酸カルシウム処理区は２．３４％（１．４ｍＭ），０％（４ｍＭ），０％（１０ｍＭ），１．４３％（２０ｍＭ）であった。一方、接種２０日目の発病株率は無処理区１００％に対して、蟻酸カルシウム処理区は４８．３％（０．４ｍＭ），７．１４％（４ｍＭ〉，１．４３％（１０ｍＭ），１．４３％（２０ｍＭ）であった。以上の結果から、接種条件が非常に厳しい瓶培養試験においてカルシウム資材による茎疫病に対する抵抗性増強効果が確認できた。 (2) Bottle culture test (agar medium inoculation method)
Test method: Soybean agar medium (0.7% agar and 1.3% sucrose) treated with an aqueous solution of calcium formate (calcium concentration 0.4, 4, 10, 20 mM, untreated section 0 mM) Sowing. After confirming the primary leaves, the mycelia cultured for 7 days in PDA medium were pasted on the border of soybean and inoculated. The investigation was conducted every day until the 20th day after inoculation. The varieties were Meiko Koguro and the fungus was Race E (Hyogo).
Result: As shown in Table 2. That is, the diseased strain rate on the 7th day after inoculation was 58.5% in the untreated group, whereas the calcium formate-treated group was 2.34% (1.4 mM), 0% (4 mM), 0% (10 mM), 1 .43% (20 mM). On the other hand, the diseased strain rate on the 20th day of inoculation was 100% for the untreated group, while 48.3% (0.4 mM), 7.14% (4 mM), 1.43% (10 mM) for the calcium formate treated group. 1.43% (20 mM) From the above results, it was possible to confirm the effect of enhancing the resistance against stalk disease caused by calcium materials in a bottle culture test under very severe inoculation conditions.

（３）土壌施用試験（含菌培地接種法）
試験方法：プラスティックセルトレイにバーミュキュライトを入れ、大豆を播種した。播種後７日目に予め調製しておいた蟻酸カルシウムの水溶液(カルシウム濃度は０．４，４
，１０，２０ｍＭ、無処理区は０ｍＭ)に湛水し、１週間湛水条件下においた。品種は中
生光黒、サチユタカ、丹波黒、菌はレースＥ（兵庫）を使用し、含菌培地接種法により抵抗性増強の評価を行った。
結果：表３の通りとなった。すなわち、中生光黒の接種２０日目の発病株率は無処理区３５．７％に対して、蟻酸カルシウム処理区は２１．４％（０．４ｍＭ），３．４％（４ｍＭ），３．７％（１０ｍＭ），３．２％（２０ｍＭ）であった。一方、サチユタカの接種２０日目の発病株率は無処理区２８．６％に対して、蟻酸カルシウム処理区は１３．１％（０．４ｍＭ），６．３％（４ｍＭ），０％（１０ｍＭ），０％（２０ｍＭ）であった。丹波黒の接種２０日目の発病株率は無処理区９３．３％に対して、蟻酸カルシウム処理区は１９．１％（０．４ｍＭ），５．０％（４ｍＭ），５．０％（１０ｍＭ），７．４％（２０ｍＭ）であった。 (3) Soil application test (bacteria-containing medium inoculation method)
Test method: Vermiculite was placed in a plastic cell tray and seeded with soybeans. An aqueous solution of calcium formate prepared in advance 7 days after sowing (calcium concentration is 0.4, 4
, 10, 20 mM, and 0 mM in the non-treated section), and the mixture was left under the irrigation condition for 1 week. The varieties were Meiko Koguro, Sachiyutaka, Tamba Kuro, and the fungus was Race E (Hyogo), and the resistance enhancement was evaluated by the bacterial culture medium inoculation method.
Result: As shown in Table 3. That is, the pathogenic rate on the 20th day of inoculation with Meiko Koguro was 35.7% in the untreated group, whereas 21.4% (0.4 mM), 3.4% (4 mM) in the calcium formate-treated group, They were 3.7% (10 mM) and 3.2% (20 mM). On the other hand, on the 20th day of inoculation with Sachiyutaka, the disease-causing strain rate was 28.6% in the untreated group, whereas the calcium formate-treated group was 13.1% (0.4 mM), 6.3% (4 mM), 0% ( 10 mM) and 0% (20 mM). On the 20th day of inoculation of Tamba-Kuro, the disease-causing strain rate is 93.3% in the non-treated group, whereas the calcium formate-treated group is 19.1% (0.4 mM), 5.0% (4 mM), 5.0% (10 mM), 7.4% (20 mM).

（４）土壌施用試験（遊走子接種法）
試験方法：プラスティックセルトレイにバーミュキュライトを入れ、大豆を播種した。播種後７日目に予め調製しておいた蟻酸カルシウムの水溶液(カルシウム濃度は０．４，４
，１０，２０ｍＭ、無処理区は０ｍＭ)に湛水し、１週間湛水条件下においた。品種は中
生光黒、菌はレースＥ（兵庫）を使用し、遊走子接種法（１０³×２ｍｌ）で評価を行っ
た。
結果：表４の通りとなった。すなわち、接種７日目の発病株率は無処理区４３．４％に対して、蟻酸カルシウム処理区は１２．７％（０．４ｍＭ），５．００％（４ｍＭ），１．８５％（１０ｍＭ），４．０５％（２０ｍＭ）であった。接種２０日目の発病株率は無処理区１００％に対して、スイカル処理区は６８．０％（０．４ｍＭ），２９．９％（４ｍＭ），１６．０３％（１０ｍＭ），５．７９％（２０ｍＭ）であった。 (4) Soil application test (Plant inoculation method)
Test method: Vermiculite was placed in a plastic cell tray and seeded with soybeans. An aqueous solution of calcium formate prepared in advance 7 days after sowing (calcium concentration is 0.4, 4
, 10, 20 mM, and 0 mM in the non-treated section), and the mixture was left under the irrigation condition for 1 week. The varieties used were Meiko Kurokuro, the fungus used Race E (Hyogo), and evaluation was performed by the zoospore inoculation method (10 ³ × 2 ml).
Result: As shown in Table 4. That is, the diseased strain rate on the 7th day of inoculation is 43.4% in the untreated group, whereas in the calcium formate-treated group, 12.7% (0.4 mM), 5.00% (4 mM), 1.85% ( 10 mM) and 4.05% (20 mM). On the 20th day after inoculation, the disease-causing strain rate was 100% in the untreated group, while the water-treated group was 68.0% (0.4 mM), 29.9% (4 mM), 16.6.0% (10 mM), and 5. 79% (20 mM).

（５）定植前湛水
上記の（２）瓶培養試験（寒天培地接種法）、（３）土壌施用試験（含菌培地接種法）及び（４）土壌施用試験（遊走子接種法）から、特に（３）、（４）から１週間湛水条件下におくことが茎疫病の発生を抑制するのに有効であることが分かる。 (5) Pre-planting flooding From the above (2) bottle culture test (agar medium inoculation method), (3) soil application test (bacteria-containing medium inoculation method) and (4) soil application test (zoospore inoculation method), In particular, it can be seen from (3) and (4) that it is effective to suppress the occurrence of stalk disease by placing it under a flooding condition for one week.

これを前提にして栽培試験を実施した結果、プラスティックセルトレイに播種し、初生葉確認の日から1週間（プラスティックセルトレイのまま）大豆の根鉢部分をカルシウム
溶液に湛水処理してから定植すれば、茎疫病の発生を抑制できることを確認した。 As a result of carrying out a cultivation test on the premise of this, if seeded in a plastic cell tray, and after one week from the date of confirmation of the initial leaves (with the plastic cell tray), the soybean root pot portion is submerged in a calcium solution and then planted It was confirmed that the occurrence of stem plague can be suppressed.

カルシウムの茎疫病に対する抵抗性増強には、１）菌感染前のペクチン酸との結合による細胞壁の強化だけでなく、２）感染後ではカルシウムイオンまたは水溶性カルシウムによる植物体内でのシグナル伝達、菌の増殖や移行の制御が関わっていると考えられ、定植前の湛水処理はこれら１）、２）の両方に有効である。
［その他］
実施例では本発明をダイズに適用した例を説明したが、本発明はアズキにも適用できる。 In order to enhance the resistance of calcium to stem blight, not only 1) strengthening the cell wall by binding to pectic acid before infection, but 2) signal transmission in the plant by calcium ions or water-soluble calcium after infection, bacteria It is thought that the control of the growth and migration of the plant is involved, and the flooding treatment before planting is effective for both 1) and 2).
[Others]
In the examples, the present invention is applied to soybean, but the present invention can also be applied to azuki bean.

Claims

Seedlings of soybean or red bean, planted after the calcium concentration was flooding treatment in an aqueous solution of 0.4 to 10 mM,
A method for enhancing resistance to stem blight, characterized in that the calcium is derived from calcium formate .

The flooding process, enhancing the resistance method for claim 1 Symbol mounting stem blight characterized by being carried out over four days.

3. The method for enhancing resistance to stem plague according to claim 1 or 2 , wherein the flooding treatment is started within 2 days after confirmation of the primary leaves.

The method for enhancing resistance to stem plague according to claim 3 , wherein the flooding treatment is performed immediately after confirmation of primary leaves.

5. The method for enhancing resistance to stem blight according to claim 4 , wherein the flooding treatment is carried out for 1 week after confirmation of the primary leaves.