JP2009225696A - Method for enhancing seed stress tolerance, and method of disinfection treatment - Google Patents
Method for enhancing seed stress tolerance, and method of disinfection treatment Download PDFInfo
- Publication number
- JP2009225696A JP2009225696A JP2008072787A JP2008072787A JP2009225696A JP 2009225696 A JP2009225696 A JP 2009225696A JP 2008072787 A JP2008072787 A JP 2008072787A JP 2008072787 A JP2008072787 A JP 2008072787A JP 2009225696 A JP2009225696 A JP 2009225696A
- Authority
- JP
- Japan
- Prior art keywords
- seed
- seeds
- aqueous solution
- hot water
- water treatment
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Abstract
Description
本発明は、種子のストレスに対する耐性を強化する方法、及び種子を消毒処理する方法に関するものである。 The present invention relates to a method for enhancing resistance to seed stress and a method for disinfecting seeds.
農作物の栽培において、温度や水分などの物理的ストレス、及び病害虫や雑草などの生物的ストレスに耐える丈夫な苗を育てることは極めて重要である。丈夫な苗を育てるためには、ストレスに強い性質を持った種子を用いる必要がある。ストレスに強い種子を生産・流通する技術が開発できれば、農薬使用量の削減及び収量や品質の安定化が図れ、農業生産に大きく寄与できる。 In the cultivation of crops, it is extremely important to grow strong seedlings that can withstand physical stresses such as temperature and moisture, and biological stresses such as pests and weeds. In order to grow strong seedlings, it is necessary to use seeds that are resistant to stress. If technology that produces and distributes stress-resistant seeds can be developed, the use of pesticides can be reduced and the yield and quality can be stabilized, greatly contributing to agricultural production.
例えば、従来から行われている、種子を温水に浸漬させて種子伝染性病害を抑える温湯処理において、病害を十分に防止するには温水の温度を高くする必要があるが、温水の温度を高くすると種子の発芽不良が生じる。水稲を用いた試験によると、温度６２℃の温湯処理では、良好な病害防除効果が得られるものの、種子の発芽不良が見られ、温度５８℃の温湯処理では、種子の発芽に影響はないものの、病害防除効果に低下が見られ、さらに、温度６０℃の温湯処理では、種子の発芽及び病害防除が共に不十分であったとの結果が報告されている。 For example, in the conventional hot water treatment in which seeds are immersed in warm water to suppress seed infectious diseases, it is necessary to increase the temperature of the hot water in order to sufficiently prevent the disease. Then, seed germination failure occurs. According to a test using paddy rice, although hot water treatment at a temperature of 62 ° C. can provide a good disease control effect, seed germination is poor, and hot water treatment at a temperature of 58 ° C. does not affect seed germination. In addition, a decrease in the disease control effect was observed, and it was reported that the hot water treatment at a temperature of 60 ° C. was insufficient for both germination and disease control of seeds.
このことは、水稲において病原菌の死滅温度と種子の死滅温度とが近接していること示している。そうすると、種子の耐熱性を数℃でも上げることができれば、病原菌の死滅温度と種子の死滅温度との温度差が広がり、種子の発芽等に影響を与えることなく、温湯処理によって病害の防除を行えるようになる。 This indicates that the killing temperature of pathogenic bacteria is close to the killing temperature of seeds in rice. Then, if the heat resistance of the seed can be increased even at several degrees C, the temperature difference between the killing temperature of the pathogen and the killing temperature of the seed widens, and the disease can be controlled by the hot water treatment without affecting the germination of the seed. It becomes like this.
耐熱性などの種子のストレス耐性を強化するには、遺伝子組み換え手法を用いることも可能であり、実際にそのような研究開発も種々行われている。しかし、遺伝子組み換えを用いた場合、ストレス耐性を強化する対象の品種毎に遺伝子組み換え体を作出する必要があり、多大な労力、時間を要する。また、遺伝子組み換え処理された種子の栽培については、健康や環境に悪影響があるのではと不安を抱く者も多く、消費者、生産者、行政などの間で時間をかけて合意形成すべき問題であって、わが国において早期に実用化できる農業技術とはいえない。それゆえ、遺伝子組み換え手法を用いずに、種子のストレス耐性を高める技術の創出が強く望まれている。
本発明はこのような現状を踏まえてなされたものであり、その目的とするところは、遺伝子組み換え手法を用いずに、種子のストレス耐性を高める方法を提供することにある。 The present invention has been made in view of such a current situation, and an object of the present invention is to provide a method for increasing the stress tolerance of seeds without using a genetic recombination technique.
また、本発明の他の目的は、種子の発芽等を阻害することなく、また化学合成農薬等の薬剤を用いることなく種子の消毒処理を行える方法を提供することにある。 Another object of the present invention is to provide a method capable of disinfecting seeds without inhibiting seed germination or the like and without using chemicals such as chemically synthesized agricultural chemicals.
さらに、本発明の他の目的は、薬剤を使用せずに殺菌消毒された種子を提供することにある。 Furthermore, it is another object of the present invention to provide a sterilized seed that does not use a drug.
本発明者等は、前記目的を達成すべく鋭意検討を重ねた結果、種子に対して含水量を制限するというストレスを与えることによって、物理的ストレスや生物的ストレスに対する耐性が誘発されるという新たな知見を得て本発明をなすに至った。すなわち、本発明に係る種子のストレス耐性強化方法は、浸透圧が０．５〜４ＭＰａの範囲の水溶液に種子を浸漬することを特徴とする。 As a result of intensive studies to achieve the above object, the present inventors have newly introduced that resistance to physical stress and biological stress is induced by applying a stress that restricts the water content to seeds. As a result, the present invention has been achieved. That is, the seed stress tolerance enhancing method according to the present invention is characterized in that the seed is immersed in an aqueous solution having an osmotic pressure in the range of 0.5 to 4 MPa.
種子の浸漬時間としては、３時間〜１２０時間の範囲が好ましい。また使用する水溶液としては、ポリエチレングリコール、マンニトール、ソルビトール、硝酸カリウム、リン酸カリウム、炭酸カルシウム、塩化ナトリウムの少なくとも１つを含有する水溶液が好ましい。 The seed soaking time is preferably in the range of 3 hours to 120 hours. The aqueous solution used is preferably an aqueous solution containing at least one of polyethylene glycol, mannitol, sorbitol, potassium nitrate, potassium phosphate, calcium carbonate, and sodium chloride.
ストレス耐性を強化した種子を保存する観点からは、前記水溶液に種子を浸漬させた後、種子を水洗し、乾燥させるのが好ましい。 From the viewpoint of preserving seeds with enhanced stress tolerance, it is preferable to immerse the seeds in the aqueous solution and then wash and dry the seeds.
また、本発明によれば、浸透圧が０．５〜４ＭＰａの範囲の水溶液に種子を浸漬する工程と、前記種子を温湯処理する工程とを有することを特徴とする種子の消毒処理方法が提供される。 In addition, according to the present invention, there is provided a seed disinfection method characterized by comprising a step of immersing seeds in an aqueous solution having an osmotic pressure in the range of 0.5 to 4 MPa, and a step of treating the seeds with hot water. Is done.
前記温湯処理の温度は４５〜７０℃の範囲が好ましく、温湯処理の時間は１分〜６０分の範囲が好ましい。また、ストレス耐性を付与した種子であっても、長期間にわたり水分を含んだ状態で高温下に放置すると、発芽不良が起こる可能性があるため、前記の温湯処理後、種子を冷却するのが好ましい。 The temperature of the hot water treatment is preferably in the range of 45 to 70 ° C., and the time of the hot water treatment is preferably in the range of 1 minute to 60 minutes. Moreover, even if the seed has been given stress tolerance, if it is left under high temperature in a state of containing moisture for a long period of time, germination failure may occur. preferable.
さらに、本発明によれば、前記のいずれかに記載の方法で処理された種子が提供される。 Furthermore, according to this invention, the seed processed by the method in any one of the above is provided.
本発明に係る種子のストレス耐性強化方法では、遺伝子組み換え手法を用いることなく、所定範囲の浸透圧の水溶液に種子を浸漬するという簡単な処理によって、種子のストレス耐性を高めることができる。これにより、大きなコストや長期間の開発期間を要することなく、また、健康や環境への悪影響の心配もなく、農薬使用量の削減及び収量や品質の安定化が図れる。 In the method for enhancing stress tolerance of seeds according to the present invention, the stress tolerance of seeds can be increased by a simple treatment of immersing seeds in an aqueous solution having an osmotic pressure within a predetermined range without using a genetic recombination technique. As a result, the amount of agricultural chemicals used can be reduced and the yield and quality can be stabilized without requiring a large cost and a long development period, and without worrying about adverse effects on health and the environment.
また、本発明に係る種子の消毒処理では、種子のストレス耐性を強化した後、温湯処理を行うので、発芽不良等を招くことなく、通常の処理温度よりも高い温度で温湯処理を行うことができ、病害の防除を確実に行えるようになる。 Moreover, in the seed disinfection treatment according to the present invention, hot water treatment is performed after enhancing the stress tolerance of seeds, so that hot water treatment can be performed at a temperature higher than the normal treatment temperature without causing germination failure or the like. It will be possible to control the disease reliably.
さらに、本発明の種子では、遺伝子組み換え手法を用いることなく、ストレス耐性が強化され、また薬剤を使用することなく殺菌消毒がなされているので、農薬使用量の削減及び収量や品質の安定化が図れる。 Furthermore, in the seeds of the present invention, stress tolerance is enhanced without using a genetic recombination technique, and sterilization and disinfection is performed without using a drug, so that the amount of agricultural chemicals used can be reduced and the yield and quality can be stabilized. I can plan.
本発明に係る種子のストレス耐性強化方法の大きな特徴は、所定範囲の浸透圧を有する水溶液に種子を浸漬することにある。所定範囲の浸透圧の水溶液に種子を浸漬すると、種子の含水量が制限される。水溶液の浸透圧が高いほど種子の含水量は低く制限される。このようなストレスを種子に与えることによって、物理的ストレスや生物的ストレスに対する耐性が誘発される。 A major feature of the seed stress tolerance enhancing method according to the present invention is that the seed is immersed in an aqueous solution having an osmotic pressure within a predetermined range. When seeds are immersed in an aqueous solution having an osmotic pressure within a predetermined range, the moisture content of the seeds is limited. The higher the osmotic pressure of the aqueous solution, the lower the moisture content of the seed. By applying such stress to seeds, tolerance to physical stress or biological stress is induced.
上記方法によって種子にストレス耐性が誘発される具体的機構は未だ明確ではないが、次のような機構であろうと推測される。植物のストレス耐性には、活性酸素消去系が中心的に関わっていることが分かってきつつある。実際に、遺伝子組み換え操作により作物に活性酸素消去酵素遺伝子を導入し、植物体のストレス耐性を高める研究では、水稲におけるカラターゼ高発現体形質転換体での塩分耐性の向上や、アスコルビン酸パーオキシターゼ高発現体の低温耐性の向上などが報告されている。 Although the specific mechanism by which stress tolerance is induced in seeds by the above method is not yet clear, it is presumed that the mechanism is as follows. It has been found that the active oxygen scavenging system plays a central role in plant stress tolerance. In fact, in research to increase the stress tolerance of plants by introducing an active oxygen scavenging enzyme gene into crops by genetic recombination, improvement of salinity tolerance in transformants with high expression of kalatase in rice, as well as high ascorbate peroxidase Improvement of low temperature tolerance of the expressed body has been reported.
一方、本発明者等の実験によれば、種子に対して含水量を制限してストレスを与えると、種子中の活性酸素生成が促進されることはわかっている。活性酸素は、シグナリオン分子として生物の活性酸素消去能を向上させることは、動植物を通じた多くの実験系で認められている。そうすると、種子に対して含水量を制限してストレスを与えることで、種子中に活性酸素が生成され、これによって活性酸素消去能が高まりストレス耐性が向上するものと考えられる。 On the other hand, according to the experiments by the present inventors, it has been found that when the moisture content is limited and the stress is applied to the seed, the generation of active oxygen in the seed is promoted. It has been recognized in many experimental systems through animals and plants that active oxygen improves the active oxygen scavenging ability of organisms as a signalion molecule. Then, it is considered that, by applying a stress to the seed while limiting the water content, active oxygen is generated in the seed, which increases the ability of scavenging active oxygen and improves stress tolerance.
そこで、本発明者等は実際に次の実験を行い、種子の活性酸素消去能の経時的変化を測定した。 Therefore, the present inventors actually performed the following experiment and measured the change with time of the active oxygen scavenging ability of the seed.
（活性酸素消去能の測定）
乾燥した水稲（品種：コシヒカリ）種子を浸透圧２ＭＰａのポリエチレングリコール（以下「ＰＥＧ」と記すことがある）水溶液に２４時間浸漬した。その後、種子を流水で１０分間洗浄し、２０分間通風乾燥した。そして、飽和塩化リチウム溶液で空気中の湿度を１１％に保持したデシケータ内に７日間放置し再乾燥させた。
次に、再乾燥した種子を不織布袋に入れ、温度６０℃の温湯に４０分間浸漬させて温湯処理を行った。温湯処理後、直ちに１０分間流水で冷却し、ペーパータオルで水気を切って発芽試験を行った。
このような種子の各処理の間、定期的にサンプリングを行い、脱頴して−８０℃で冷凍保存し、ｘｙｚ活性酸素消去発光法によって活性酸素消去能を測定した。測定結果を図１に示す。なお、ｘｙｚ活性酸素消去発光法は、活性酸素（ｘ：2%H2O2）に抗酸化物質（ｙ：種子）と触媒（ｚ：2%CH3CHO KHCO3飽和溶液）が作用し、発光する際のフォトン量（ph/pix s）を測定するものである。
(Measurement of active oxygen scavenging ability)
Dried paddy rice (variety: Koshihikari) seeds were immersed in an aqueous solution of polyethylene glycol (hereinafter sometimes referred to as “PEG”) having an osmotic pressure of 2 MPa for 24 hours. Thereafter, the seeds were washed with running water for 10 minutes and dried by ventilation for 20 minutes. Then, it was left to dry again in a desiccator in which the humidity in the air was maintained at 11% with a saturated lithium chloride solution for 7 days.
Next, the re-dried seeds were placed in a non-woven bag and immersed in hot water at a temperature of 60 ° C. for 40 minutes for hot water treatment. After the hot water treatment, the sample was immediately cooled with running water for 10 minutes, drained with a paper towel, and a germination test was performed.
Sampling was periodically performed during each treatment of such seeds, dehydrated and stored frozen at −80 ° C., and the active oxygen scavenging ability was measured by the xyz active oxygen scavenging luminescence method. The measurement results are shown in FIG. In the xyz active oxygen elimination luminescence method, an antioxidant (y: seed) and a catalyst (z: 2% CH 3 CHO KHCO 3 saturated solution) act on active oxygen (x: 2% H 2 O 2 ), It measures the amount of photons (ph / pix s) when emitting light.
図１から理解されるように、種子中の活性酸素消去能は、ＰＥＧ水溶液への浸漬過程で確かに増加している。そして、ＰＥＧ水溶液への浸漬工程によって増加した活性酸素消去能は、乾燥工程の間も維持され、温湯処理によって一時的にさらに増加した後、通常の種子と同じ水準となった。 As can be seen from FIG. 1, the ability to scavenge active oxygen in seeds certainly increases in the course of immersion in an aqueous PEG solution. And the active oxygen scavenging ability increased by the immersion process in PEG aqueous solution was maintained even during the drying process, and after temporarily further increasing by the hot water treatment, it became the same level as that of normal seeds.
本発明のストレス耐性強化方法で用いる水溶液の溶質としては、特に限定はないが、通常は、ポリエチレングリコールやマンニトール、ソルビトール等の糖アルコール類；硝酸カリウム等の硝酸塩やリン酸カリウム等のリン酸塩、あるいは炭酸カルシウムや塩化ナトリウム等が好ましい。 The solute of the aqueous solution used in the stress tolerance enhancing method of the present invention is not particularly limited. Usually, sugar alcohols such as polyethylene glycol, mannitol, sorbitol; nitrates such as potassium nitrate; phosphates such as potassium phosphate; Or calcium carbonate, sodium chloride, etc. are preferable.
また、水溶液の浸透圧は０．５〜４ＭＰａの範囲である必要がある。水溶液の浸透圧が０．５ＭＰａよりも小さいと、種子の含水率が高くなるため、処理中に発芽準備が進み、処理中に種子が発芽したり、ストレス耐性がかえって低下するという問題がある。他方、水溶液の浸透圧が４ＭＰａより大きいと、ストレス耐性の誘導に十分な水分を種子が吸収できないという問題がある。より好ましい水溶液の浸透圧は１〜４ＭＰａの範囲である。 The osmotic pressure of the aqueous solution needs to be in the range of 0.5 to 4 MPa. When the osmotic pressure of the aqueous solution is less than 0.5 MPa, the moisture content of the seeds increases, so that germination preparation proceeds during the treatment, and the seeds germinate during the treatment, and the stress tolerance is reduced. On the other hand, if the osmotic pressure of the aqueous solution is larger than 4 MPa, there is a problem that the seeds cannot absorb sufficient moisture for inducing stress tolerance. A more preferable osmotic pressure of the aqueous solution is in the range of 1 to 4 MPa.
なお、浸透圧の測定は、溶質が多価アルコール等のポリマーである場合は、例えば、ミッチェル等の研究（Plant Physiol Vol.51:914-916、1973）で明らかにされた、水１ｋｇ当たりの溶質量Ｃ（ｇ）及び液温Ｔと浸透圧ψ（ｂａｒ）の関係を示す次式、
ψ(bar)＝-(1.18×10−２)Ｃ−(1.18×10−４)Ｃ2＋(2.67×10−４)ＣＴ＋(8.39×10−７)Ｃ2Ｔ
において、特に記載していない限り液温Ｔを１５℃として算出すればよい。
一方、溶質がポリマーではない無機塩類等の場合は、例えば、ファント・ホッフによる次式、
ＰＶ ＝ ｎＲＴ
（Ｐ：浸透圧、ｎ：溶質のモル数、Ｖ：溶液の体積、Ｔ：絶対温度、Ｒ：気体定数）
により、特に記載していない限り液温を１５℃として算出すればよい。
In the measurement of osmotic pressure, when the solute is a polymer such as a polyhydric alcohol, it is clarified in, for example, a study by Mitchell (Plant Physiol Vol. 51: 914-916, 1973). The following equation showing the relationship between the melt mass C (g) and the liquid temperature T and the osmotic pressure ψ (bar),
ψ (bar) =-(1.18 × 10 −2 ) C− (1.18 × 10 −4 ) C 2 + (2.67 × 10 −4 ) CT + (8.39 × 10 −7 ) C 2 T
In this case, the liquid temperature T may be calculated as 15 ° C. unless otherwise specified.
On the other hand, in the case of inorganic salts, etc., where the solute is not a polymer, for example, the following formula by Fant Hoff,
PV = nRT
(P: osmotic pressure, n: number of moles of solute, V: volume of solution, T: absolute temperature, R: gas constant)
Therefore, the liquid temperature may be calculated as 15 ° C. unless otherwise specified.
次に、本発明者等は、種子を浸漬させる水溶液の浸透圧と浸漬時間との関係について検討を行った。まず、コシヒカリ種子を用いて、この種子を、浸透圧１，２，３，４ＭＰａのＰＥＧ水溶液に０，２４，７２，１２０時間浸漬した。その後、種子を流水で１０分間洗浄し、２０分間通風乾燥した。そして、飽和塩化リチウム溶液で空気中の湿度を１１％に保持したデシケータ内に７日間放置し再乾燥させた。次に、再乾燥した種子を不織布袋に入れ、温度６０℃の温湯に４０分間浸漬させて温湯処理を行った。温湯処理後、直ちに１０分間流水で冷却し、ペーパータオルで水気を切って発芽試験を行った。
発芽試験は、９０ｍｍのシャーレ内の湿潤濾紙上に、前記処理した種子５０粒を播き、３０℃光条件（光強度：6.5〜13.5μmmol・S-1/m-2）のインキューベータ内に置いて７日後の発芽率を測定した。結果を図２に示す。
Next, the present inventors examined the relationship between the osmotic pressure of an aqueous solution in which seeds are immersed and the immersion time. First, using Koshihikari seeds, the seeds were immersed in an aqueous PEG solution having an osmotic pressure of 1, 2, 3, 4 MPa for 0, 24, 72, 120 hours. Thereafter, the seeds were washed with running water for 10 minutes and dried by ventilation for 20 minutes. Then, it was left to dry again in a desiccator in which the humidity in the air was maintained at 11% with a saturated lithium chloride solution for 7 days. Next, the re-dried seeds were placed in a non-woven bag and immersed in hot water at a temperature of 60 ° C. for 40 minutes for hot water treatment. After the hot water treatment, the sample was immediately cooled with running water for 10 minutes, drained with a paper towel, and a germination test was performed.
In the germination test, 50 treated seeds were sown on wet filter paper in a 90 mm petri dish, and placed in an incubator under 30 ° C. light conditions (light intensity: 6.5 to 13.5 μmmol · S −1 / m −2 ). The germination rate after 7 days was measured. The results are shown in FIG.
図２は、縦軸を発芽率とし、横軸をＰＥＧ水溶液への浸漬時間として、ＰＥＧ水溶液の浸透圧ごとに、浸漬時間に対する発芽率の変化をプロットしたものである。浸透圧１ＭＰａのＰＥＧ水溶液を除き、浸透圧２，３，４ＭＰａのＰＥＧ水溶液の浸漬処理では、浸漬時間が２４時間で発芽率は約９５％と最大値を示し、その後、浸漬時間が長くなると発芽率は低下する傾向が見られた。 FIG. 2 is a plot of changes in germination rate versus immersion time for each osmotic pressure of the PEG aqueous solution, with the vertical axis being the germination rate and the horizontal axis being the immersion time in the PEG aqueous solution. Except for the PEG aqueous solution with an osmotic pressure of 1 MPa, the immersion treatment of the PEG aqueous solution with an osmotic pressure of 2,3,4 MPa shows a maximum germination rate of about 95% when the immersion time is 24 hours. The rate tended to decrease.
一方、浸透圧１ＭＰａのＰＥＧ水溶液の浸漬処理では、２４時間浸漬処理した種子は発芽率が約６０％と、浸漬処理しない種子と差がなく、その後７２時間、１２０時間浸漬処理した種子は発芽率が０％であった。これは次のような原因によるものであると推測される。すなわち、水溶液の浸透圧が低いほど種子は吸水しやすくなり、種子の含水量は増加する。また浸漬時間が長くなるほど種子の含水量は増加する。このため、浸透圧１ＭＰａのＰＥＧ水溶液の浸漬処理では、浸漬時間が２４時間でも種子の含水量が十分に多くなってしまい、耐性強化に必要なストレスを種子に与えられなかった。そして、２４時間を超えて長時間浸漬されることによって、種子の含水量が多くなって種子の発芽準備が促進され、これに伴い熱や乾燥等に対する耐性が著しく低下し種子は死滅したと考えられる。そうすると、浸透圧１ＭＰａのＰＥＧ水溶液の浸漬処理では、浸漬時間を２４時間未満、例えば１２時間にすれば発芽率は６０％よりも大きな値となるであろうことが予測され、本発明者等は今後このような確認実験を行う予定である。 On the other hand, in the dip treatment with an aqueous PEG solution having an osmotic pressure of 1 MPa, the seeds that were soaked for 24 hours had a germination rate of about 60%, which was not different from the seeds that were not soaked. Was 0%. This is presumably due to the following reasons. That is, the lower the osmotic pressure of the aqueous solution, the easier the seed absorbs water, and the moisture content of the seed increases. In addition, the moisture content of the seed increases as the soaking time increases. For this reason, in the immersion treatment of the PEG aqueous solution having an osmotic pressure of 1 MPa, the moisture content of the seeds was sufficiently increased even when the immersion time was 24 hours, and the stress necessary for enhancing the resistance could not be given to the seeds. And, it is considered that the seeds have been killed because the moisture content of the seeds is increased and the germination preparation of the seeds is promoted by being soaked for more than 24 hours, and the resistance to heat and drying is significantly reduced. It is done. Then, in the immersion treatment of the PEG aqueous solution having an osmotic pressure of 1 MPa, it is predicted that if the immersion time is less than 24 hours, for example, 12 hours, the germination rate will be larger than 60%. Such confirmation experiments will be conducted in the future.
以上の実験結果及び発明者等の推測によれば、発芽率は、浸漬時間とともに高くなり、最大値となった後低くなる、いわゆる上に凸の曲線形状を描くと考えられ、さらに発芽率の最大値は、水溶液の浸透圧が低いほど浸漬時間の短いところに現れると考えられる。種子の浸漬時間は、このような傾向を踏まえた上で、浸漬する水溶液の浸透圧及び種子の種類などから適宜決定すればよく、通常は、５時間〜１２０時間の範囲が好ましい。 According to the above experimental results and the inventors' estimation, the germination rate is considered to draw a so-called convex curve shape that increases with the immersion time and decreases after reaching the maximum value. It is considered that the maximum value appears at a place where the immersion time is shorter as the osmotic pressure of the aqueous solution is lower. The soaking time of the seeds may be appropriately determined based on such a tendency, based on the osmotic pressure of the aqueous solution to be soaked, the kind of seeds, and the like, and is usually preferably in the range of 5 hours to 120 hours.
本発明のストレス耐性強化方法では、所定範囲の浸透圧の水溶液に種子を所定時間浸漬した後、乾燥させるのが好ましい。これによって、活性酸素消去能が高まりストレス耐性が向上する。乾燥方法は、前述の調湿されたデシケータに放置する方法に限定されるものではなく、従来公知の方法を用いることができる。また、乾燥時間に限定はなく、種子の種類や含水量などから適宜決定すればよい。 In the stress tolerance enhancing method of the present invention, it is preferable that the seed is dipped in an aqueous solution having a osmotic pressure within a predetermined range for a predetermined time and then dried. As a result, the active oxygen scavenging ability is increased and the stress resistance is improved. The drying method is not limited to the method of leaving it in the humidity-controlled desiccator described above, and a conventionally known method can be used. Moreover, there is no limitation in drying time, What is necessary is just to determine suitably from the kind of seed, moisture content, etc.
本発明の方法が適用できる種子としては、例えば、レタス、ゴボウ等のキク科作物、ネギ、タマネギ、ニラ等のユリ科作物、カンラン、ハクサイ、ダイコン等のアブラナ科作物、ナス、トマト、台木ナス、トウガラシ等のナス科作物、ニンジン、セロリ、パセリ等のセリ科作物、テンサイ、ホウレンソウ等のアカザ科作物、キュウリ、メロン等のウリ科作物、スイートコーン等のイネ科作物等の野菜種子；ユーストマ、パンジー、ベゴニア等の花種子；ギニアグラス、ローズグラス等の牧草種子；イネ、コムギ、オオムギ、トウモロコシ等の穀物種子；ユーカリ等の樹木種子；ダイズ、エンドウ等の豆科作物、ヒマワリ等のキク科作物、ソバ等のタデ科作物、食用のアワ、キビ、ヒエ等のイネ科作物の食用および工芸作物等の種子が挙げられる。 The seeds to which the method of the present invention can be applied include, for example, asteraceae crops such as lettuce and burdock, lily family crops such as leek, onion and leek, cruciferous crops such as kanran, Chinese cabbage and radish, eggplant, tomato and rootstock Vegetable seeds such as eggplants, peppers and other solanaceous crops, carrots, celery, parsley and other cereals crops, sugar beet, spinach and other red crustacean crops, cucumber, melon and other cucurbits, sweet corn and other rice Flower seeds such as Eustoma, Pansy, Begonia; Grass seeds such as guinea grass and rosegrass; Grain seeds such as rice, wheat, barley and corn; Tree seeds such as eucalyptus; Legumes such as soybeans and peas; Examples include seeds such as asteraceae crops, buckwheat crops such as buckwheat, edible millet, millet, millet, etc. .
次に、本発明に係る種子の消毒処理方法について説明する。この消毒処理方法は、前述の方法によってストレスに対する耐性が強化された種子を、温湯処理することが大きな特徴である。これにより、従来の温湯処理に比べて高い温度で温湯処理することが可能となり、発芽不良等を招くことなく病害の防除を効果的に行えるようになる。 Next, the seed disinfection method according to the present invention will be described. This disinfecting treatment method is characterized in that the seed whose resistance to stress is enhanced by the above-described method is treated with hot water. This makes it possible to perform hot water treatment at a higher temperature than conventional hot water treatment, and to effectively control diseases without causing poor germination and the like.
以下、本発明者等の行った実験に基づき本発明の消毒処理方法を説明する。まず、浸透圧４ＭＰａのＰＥＧ水溶液に２４時間浸漬した水稲（品種：コシヒカリ）種子を、前記と同様に、流水で１０分間洗浄し、２０分間通風乾燥した後、飽和塩化リチウム溶液で空気中の湿度を１１％に保持したデシケータ内に７日間放置し再乾燥させた。次に、再乾燥した種子を不織布袋に入れ、温度５５，６０，６５℃の温湯に各８段階の浸漬時間で温湯処理を行った。温湯処理後、直ちに１０分間流水で冷却し、ペーパータオルで水気を切って発芽試験を行った。発芽試験は、前述と同様の方法で行った。 Hereinafter, the disinfection processing method of the present invention will be described based on experiments conducted by the present inventors. First, paddy rice (variety: Koshihikari) seeds immersed in an aqueous PEG solution having an osmotic pressure of 4 MPa for 24 hours was washed with running water for 10 minutes and air-dried for 20 minutes, and then the humidity in the air with a saturated lithium chloride solution. Was left to dry in a desiccator maintained at 11% for 7 days. Next, the re-dried seeds were placed in a non-woven bag, and hot water treatment was performed in hot water at temperatures of 55, 60, and 65 ° C. for each of eight stages of immersion time. After the hot water treatment, the sample was immediately cooled with running water for 10 minutes, drained with a paper towel, and a germination test was performed. The germination test was performed in the same manner as described above.
種子の耐熱性評価として、耐熱性モデル（武山ら,日作紀,76 別 1,36-37,2007）に基づき、発芽率が９５％となる温湯温度−浸漬時間の回帰式を求め、この回帰式から温湯処理の時間と限界温湯温度との関係、及び温湯処理の温度と限界温湯時間との関係を算出した。算出結果を表１及び表２に示す。 To evaluate the heat resistance of seeds, a regression equation of hot water temperature-immersion time at which the germination rate is 95% was obtained based on a heat resistance model (Takeyama et al., Nisakuki, 76, 1,36-37, 2007). From the regression equation, the relationship between the hot water treatment time and the limit hot water temperature, and the relationship between the hot water treatment temperature and the limit hot water time were calculated. The calculation results are shown in Tables 1 and 2.
表１は、温湯処理の時間を５分，１０分，・・・３０分と変えたときの、発芽率が９５％となる限界温湯温度である。例えば、温湯処理時間が１５分間の場合、限界温湯温度は、通常の種子では６０．６℃であるのに対し、耐性強化処理を行った種子では限界温湯温度は６２．１℃と通常の種子に比べ１．５℃も高くなっていることがわかる。その他の各温湯処理時間においても、限界温湯温度は、耐性強化処理を行った種子の方が、通常の種子よりも１．３℃〜１．７℃高い温度であった。 Table 1 shows the limit hot water temperature at which the germination rate becomes 95% when the hot water treatment time is changed to 5 minutes, 10 minutes,..., 30 minutes. For example, when the hot water treatment time is 15 minutes, the limit hot water temperature is 60.6 ° C. for normal seeds, while the limit hot water temperature is 62.1 ° C. for seeds subjected to tolerance enhancement treatment, which is normal seeds. It can be seen that the temperature is as high as 1.5 ° C. In each other hot water treatment time, the limit hot water temperature was 1.3 ° C. to 1.7 ° C. higher than that of normal seeds in the seed subjected to the tolerance enhancement treatment.
また表２は、温湯処理の温度を５５℃，５６℃，・・・６５℃と変えたときの、発芽率が９５％となる限界温湯時間である。例えば、温湯処理温度が６０℃の場合、限界温湯時間は、通常の種子では１７．０分間であるのに対し、耐性強化処理を行った種子では２１．７分間と通常の種子に比べ４．７分も長くなっていることがわかる。その他の温湯処理温度においても、限界温湯時間は、耐性強化処理を行った種子の方が、通常の種子よりも２．３〜９．６分間長くなった。 Table 2 shows the limit hot water time when the germination rate is 95% when the temperature of the hot water treatment is changed to 55 ° C., 56 ° C.,. For example, when the hot water treatment temperature is 60 ° C., the limit hot water time is 17.0 minutes for normal seeds, whereas 21.7 minutes for seeds subjected to tolerance enhancement treatment, which is 41.7% compared to normal seeds. It can be seen that it is 7 minutes longer. Even at other hot water treatment temperatures, the limit hot water time was 2.3 to 9.6 minutes longer in the seeds subjected to the resistance enhancement treatment than in the normal seeds.
以上のように、前述の耐性強化処理を行うことによって種子の熱に対する耐性が向上し、温湯処理の温度をより高く、そして処理時間をより長くできることが実験的に確かめられた。 As described above, it has been experimentally confirmed that by performing the above-described resistance enhancement treatment, the heat resistance of the seed is improved, the temperature of the hot water treatment can be increased, and the treatment time can be lengthened.
温湯処理の具体的条件は、種子の種類や防除したい病害の種類などを考慮して適宜決定すればよい。例えば、水稲種子の場合、イネばか苗病、イネいもち病、イネもみ枯細菌病及びイネ苗立枯細菌病等の主要な種子伝染性病害の防除には、温度６０℃で５〜１０分間程度の温湯処理が有効とされている。温湯処理温度としては、通常、４５〜７０℃の範囲が好ましく、温湯処理時間としては、通常、１分〜６０分の範囲が好ましい。 The specific conditions for the hot water treatment may be appropriately determined in consideration of the type of seed and the type of disease to be controlled. For example, in the case of paddy rice seeds, the control of major seed infectious diseases such as rice sapling disease, rice blast disease, rice blast bacterial disease and rice seedling bacterial disease is performed at a temperature of 60 ° C. for about 5 to 10 minutes. Hot water treatment is considered effective. As hot water processing temperature, the range of 45-70 degreeC is preferable normally, and as hot water processing time, the range of 1 minute-60 minutes is preferable normally.
温湯処理において、種子を浸漬させる液体には通常は水を使用するが、所定の溶質を含む水溶液を使用しても構わない。例えば、ストレス耐性強化処理で用いた水溶液をそのまま温湯処理に用いてもよい。すなわち、所定の浸透圧の水溶液に種子を浸漬させて、種子のストレス耐性強化をした後、種子を浸漬させた水溶液を温湯処理温度まで加熱し、温湯処理を行うのである。このような方法によれば、ストレス耐性強化と温湯処理とを同じ水溶液で行うことができ、作業性及び生産性の向上が図れる。 In the hot water treatment, water is usually used as the liquid in which the seeds are immersed, but an aqueous solution containing a predetermined solute may be used. For example, the aqueous solution used in the stress tolerance enhancement treatment may be used as it is for the hot water treatment. That is, seeds are immersed in an aqueous solution of a predetermined osmotic pressure to enhance the stress tolerance of the seeds, and then the aqueous solution in which the seeds are immersed is heated to a hot water treatment temperature to perform hot water treatment. According to such a method, stress tolerance enhancement and hot water treatment can be performed with the same aqueous solution, and workability and productivity can be improved.
また、本発明の消毒処理方法では、温湯処理後、種子を直ちに冷却するのが望ましい。温湯処理後の残熱によって種子の発芽が阻害されるのを防止するためである。冷却方法に特に限定はないが、流水による冷却が冷却効率や簡便性などの点で推奨される。 In the disinfection method of the present invention, it is desirable to cool the seed immediately after the hot water treatment. This is to prevent seed germination from being inhibited by residual heat after hot water treatment. There is no particular limitation on the cooling method, but cooling with running water is recommended in terms of cooling efficiency and simplicity.
本発明に係る方法によれば、温度や乾燥等のストレスに対して強い種子が得られ、農薬使用量の削減及び収量や品質の安定化が図れ、農業生産に大きく寄与できる。 According to the method of the present invention, seeds that are strong against stresses such as temperature and drying can be obtained, the amount of agricultural chemicals used can be reduced, and the yield and quality can be stabilized, greatly contributing to agricultural production.
Claims (8)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2008072787A JP2009225696A (en) | 2008-03-21 | 2008-03-21 | Method for enhancing seed stress tolerance, and method of disinfection treatment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2008072787A JP2009225696A (en) | 2008-03-21 | 2008-03-21 | Method for enhancing seed stress tolerance, and method of disinfection treatment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2009225696A true JP2009225696A (en) | 2009-10-08 |
Family
ID=41241863
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2008072787A Pending JP2009225696A (en) | 2008-03-21 | 2008-03-21 | Method for enhancing seed stress tolerance, and method of disinfection treatment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2009225696A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010150845A1 (en) * | 2009-06-25 | 2010-12-29 | 森下仁丹株式会社 | Method for storage of seeds |
| JP2015119691A (en) * | 2013-12-25 | 2015-07-02 | 住化農業資材株式会社 | Selection method of seed |
| CN109511306A (en) * | 2018-10-12 | 2019-03-26 | 云南滇都种业有限公司 | A kind of store method of corn seed |
| JP2019136031A (en) * | 2018-02-05 | 2019-08-22 | 国立大学法人東京農工大学 | Seed preservation method |
| CN115280931A (en) * | 2022-09-02 | 2022-11-04 | 华中农业大学 | Seed treatment method for improving stain resistance |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01199901A (en) * | 1988-02-03 | 1989-08-11 | Mitsui Petrochem Ind Ltd | Method for storing seeds, seedlings and bulbs |
| JPH07255218A (en) * | 1994-03-01 | 1995-10-09 | Sandoz Ag | Processing seed |
| JPH09233911A (en) * | 1996-03-01 | 1997-09-09 | Yazaki Corp | Germination stimulating method for plant seed |
| JPH09510604A (en) * | 1994-01-13 | 1997-10-28 | コニンクリューケ ザーイザードベドリューベン ゲブローダーズ スルイス ベー．ファウ． | Method for producing embryoid body of drought-tolerant plant and method for germination of drought-resistant embryoid body |
| JP2003023815A (en) * | 2001-07-13 | 2003-01-28 | Tiger Kawashima Co Ltd | Seed rice pretreatment method and operation manual therefor |
| JP2006512071A (en) * | 2002-12-31 | 2006-04-13 | ユニバーシティ オブ デリー | Novel rice gene OSISAP1 imparting stress tolerance and method for imparting stress tolerance |
| JP2007503391A (en) * | 2003-08-22 | 2007-02-22 | ストラー・エンタープライジズ・インコーポレーテツド | Method for improving plant growth and crop productivity by regulating plant hormone levels, ratios and / or cofactors |
-
2008
- 2008-03-21 JP JP2008072787A patent/JP2009225696A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01199901A (en) * | 1988-02-03 | 1989-08-11 | Mitsui Petrochem Ind Ltd | Method for storing seeds, seedlings and bulbs |
| JPH09510604A (en) * | 1994-01-13 | 1997-10-28 | コニンクリューケ ザーイザードベドリューベン ゲブローダーズ スルイス ベー．ファウ． | Method for producing embryoid body of drought-tolerant plant and method for germination of drought-resistant embryoid body |
| JPH07255218A (en) * | 1994-03-01 | 1995-10-09 | Sandoz Ag | Processing seed |
| JPH09233911A (en) * | 1996-03-01 | 1997-09-09 | Yazaki Corp | Germination stimulating method for plant seed |
| JP2003023815A (en) * | 2001-07-13 | 2003-01-28 | Tiger Kawashima Co Ltd | Seed rice pretreatment method and operation manual therefor |
| JP2006512071A (en) * | 2002-12-31 | 2006-04-13 | ユニバーシティ オブ デリー | Novel rice gene OSISAP1 imparting stress tolerance and method for imparting stress tolerance |
| JP2007503391A (en) * | 2003-08-22 | 2007-02-22 | ストラー・エンタープライジズ・インコーポレーテツド | Method for improving plant growth and crop productivity by regulating plant hormone levels, ratios and / or cofactors |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010150845A1 (en) * | 2009-06-25 | 2010-12-29 | 森下仁丹株式会社 | Method for storage of seeds |
| JP2015119691A (en) * | 2013-12-25 | 2015-07-02 | 住化農業資材株式会社 | Selection method of seed |
| JP2019136031A (en) * | 2018-02-05 | 2019-08-22 | 国立大学法人東京農工大学 | Seed preservation method |
| CN109511306A (en) * | 2018-10-12 | 2019-03-26 | 云南滇都种业有限公司 | A kind of store method of corn seed |
| CN115280931A (en) * | 2022-09-02 | 2022-11-04 | 华中农业大学 | Seed treatment method for improving stain resistance |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP3016493B1 (en) | Treatment for seeds disinfection | |
| Maiti et al. | Vegetable seed priming: a low cost, simple and powerful techniques for farmers’ livelihood | |
| RU2582368C2 (en) | Method of stimulating plant growth | |
| CN106804150A (en) | A kind of germination accelerating method of rice paddy seed | |
| JP2006232690A (en) | Method for preventing rice plant from bacterial disease | |
| CN105432181B (en) | The method for promoting gomuti palm seed to sprout | |
| CN104938429A (en) | Method for feeding orius sauteri | |
| JP2009225696A (en) | Method for enhancing seed stress tolerance, and method of disinfection treatment | |
| US20220248614A1 (en) | Method for eliminating pathogens in plant growing and corresponding system | |
| CN104145559B (en) | A kind of method making watermelon germination neat and consistent | |
| CN103798068B (en) | A kind of processing method of strawberry seedling | |
| CN105432769A (en) | Method for fresh keeping of dishcloth gourds by utilizing acidic electrolyzed water | |
| CN106717304A (en) | A kind of rice paddy seed sterilization method | |
| Larnyo et al. | Effect of temperature treatments on seed germination and seedling growth of jute mallow (Corchorus olitorius) | |
| CN107094394A (en) | A kind of gomuti palm seed accelerating germination method | |
| CN104663721A (en) | Treating agent for high-germination-rate disease-resistant corn seeds | |
| KR101499759B1 (en) | Large Scale Screening Method for the Evaluation of Resistance against Bakanae diseases | |
| Aliyu | The effect of Sodium Hypochlorite and Ethanol as seed sterilants on cowpea infected with Cowpea Mottle Virus | |
| JP3990691B2 (en) | Disease control method of rice | |
| RU2435350C1 (en) | Method of pre-sowing treatment of goat's rue and other perennial legume grasses seeds | |
| JP2004292354A (en) | Method for controlling disease damage to seed and coated seed | |
| JP3248875B2 (en) | Sterilization method of Japanese cabbage radish | |
| RU2292131C1 (en) | Method for presowing seed treatment | |
| Krishnotar et al. | Response of rabi maize crop to seed invigoration with magnesium nitrate and distilled water | |
| BR112020011338A2 (en) | method for producing a seed, methods for increasing the germination potential, seeds, use of glycine-betaine and plants or seedlings |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20110310 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20121003 |
|
| A131 | Notification of reasons for refusal |
Effective date: 20121030 Free format text: JAPANESE INTERMEDIATE CODE: A131 |
|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20130326 |