JPH05286813A - Method for promoting germination and initial growth of seed - Google Patents

Abstract

PURPOSE:To promote the germination and the initial growth of a plant seed, especially rice seed by treating the plant seed before germination with paclobutrazol known as a lodging preventing agent for rice. CONSTITUTION:A seed is treated with an aqueous solution of an active amount of paclobutrazol (preferably about 1-100ppb) before germination by immersing the seed in the solution or spraying the solution to the seed (preferably immersion in the solution) to promote the germination and the initial growth of the plant seed. The plant suitable for the treatment by this process is Japanese radish, carrot, spinach, etc., in addition to rice.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for promoting germination and initial growth of plant seeds.

[0002]

2. Description of the Related Art In cultivating crops, it is important to improve the germination rate and initial growth of seeds in order to secure a necessary amount of growth and obtain a stable yield.
For example, in direct seeding cultivation of rice in flooded soil, seeds are directly embedded in the paddy soil after substituting, so that the labor for raising seedlings can be saved as compared with mechanical transplant cultivation. However, in submerged soil cultivation, it is necessary to make the seeding depth uniform in order to stabilize the emergence rate and the seedling establishment rate, but the present seeding technology varies the seeding depth. In particular, when the seeding depth is 3 cm or more, the germination rate and the seedling establishment rate decrease due to the physiological disorder resulting from the lack of oxygen, and the growth of rice after emergence becomes poor.

Further, the sowing time for direct sowing in submerged soil is
It is carried out from the end of April to the middle of June, but especially when it is sown from the end of April to the middle of May, there are many opportunities to encounter a low temperature after sowing, and the seed seeds that have been seeded or the seedlings that have just emerged are cold. Due to the obstacles, the seedling establishment rate tends to decrease. As a method for promoting emergence and initial growth in direct seeding cultivation in submerged soil under various environmental stresses as described above, dressing seeds with calcium peroxide (Hodogaya Chemical trade name: Calper) has been put into practical use. There is. However, there are times when the germination and initial growth promoting effect is not sufficient even when the calper is dressed, and a method for further improving the germination and initial growth promoting effect is desired. In addition, a method that saves the trouble of dressing the calper is expected.

On the other hand, paclobutrazol is used as an agent for reducing lodging in rice. The usage is 20 to 10
This is a method of treating a submerged soil with an active ingredient amount of 12 to 18 g / 10a in advance. As a result, the culm length is shortened and lodging is reduced. It is also known that continuous growth of rice with germinated seeds of paclobutrazol (emergent seeds) at a concentration exceeding 1 ppb suppresses rice elongation (Showa 59).
Annual Report of Phytochemical Regulation Research, p.50 (1984)).

[0005]

[Means for Solving the Problems] The present inventors have found that treatment of pre-germinated plant seeds with paclobutrazol promotes germination and suppresses germination and elongation as in the case of treating germinated seeds. The present invention was completed by discovering that there is no unexpected effect of promoting initial growth.

The present invention is a method for promoting germination and initial growth of plant seeds (hereinafter referred to as the method of the present invention), which comprises treating an ungerminated plant seed with an effective amount of paclobutrazol. Examples of plant seeds include rice, radish, carrot, spinach, and the like, and particularly rice.

The form of paclobutrazol treated in the present invention is not particularly limited, but an aqueous solution form is desirable, and its concentration is usually 0.01 to 1000 ppb, preferably 1 to 100 ppb. .. Examples of the treatment method include a method of immersing seeds before germination in an aqueous solution of paclobutrazol, a method of spraying the solution with the aqueous solution, and the like, and a method of immersing seeds before germination is preferable.

When the seeds before germination are soaked, the soaking time is not particularly limited, but usually 1 hour or more,
It is preferably 5 hours or more. The seeds thus treated are washed with water, dried and sown. However, in the case of rice, after being washed with water, it is soaked in water at room temperature for 3 to 5 days for germination. The paclobutrazol used in the method of the present invention is put to practical use in the form of wettable powder, flowable, emulsion, liquid preparation and the like produced by a usual method. Further, it is also put to practical use as a mixture with other plant growth regulators, fungicides, insecticides, herbicides and other agricultural chemicals, or fertile substances.

Next, specific formulation examples containing paclobutrazol as an active ingredient will be shown, but the formulation used in the method of the present invention is not limited thereto. In the following formulation examples, "part" means part by weight. [Formulation Example] Liquid drug Paclobutrazol 0.001 part Ethanol 1.0 part Water 98.999 parts The above ingredients are mixed uniformly to give a liquid drug. In use, the above liquid agent is diluted with water 10 to 1,000,000 times and adjusted so that the concentration of the active ingredient is 0.01 to 1000 ppb.

[0010]

【Example】

[Test Example 1] A seed agent (variety: Nihonbare) before germination was immersed in an aqueous solution having a predetermined concentration prepared according to the above formulation example for 24 hours. After washing with water, soak in water to germinate,
Calpa (Hodogaya Chemical trade name) was sown separately in a section coated with Calper and a section not coated with Calper. The paddy field topsoil was put into a plastic vat (45 × 30 cm ² , height 15 cm), and 20 grains were sown in each treatment section. Sowing was performed using tweezers, and the seedlings were planted at a depth of 3 cm in the greenhouse and 2 cm in the low temperature (15 ° C. constant temperature). The water was flooded to a depth of 3 cm, and germinated and grown in a greenhouse and an outdoor climate chamber (15 ° C. constant temperature).

The test was conducted in two consecutive systems, and the greenhouse area was investigated 25 days after sowing, and the low temperature area was investigated 35 days after sowing. The results are shown in Tables 1 and 2.

[0012]

[Table 1] Table 1 Greenhouse area ─────────────────────────────── Carpar paclobutrazol Emergence rate Plant height Leaf age Raw weight Powder concentration (ppb)% cm g / 100 ──────────────────────────────── Yes 0 60 23.8 2.9 18.3 10 65 24.1 3.0 19.5 100 75 25.1 3.2 23.0 None 0 55 23.2 2.7 15.5 10 60 24.3 2.9 18.0 100 70 24.1 2.9 21.2 ──────────────────────── ────────

[0013]

[Table 2] Table 2 Low temperature zone (constant temperature of 15 ℃) ─────────────────────────────── Carpar paclobutrazole Emergence rate Plant height Leaf age Raw weight Clothes concentration (ppb)% cm g / 100 ─────────────────────────────── Yes 0 20 4.3 2.1 13.3 10 50 5.3 2.3 15.5 100 45 5.5 2.3 15.3 No 0 5 3.8 1.9 9.5 10 40 4.7 2.0 14.3 100 35 4.8 2.1 12.5 ────────────────── ──────────────

[Test Example 2] A reagent agent prepared according to the above-mentioned formulation example was made into an aqueous solution having a predetermined concentration, and carrot seeds (variety: Shin Kuroda 5 inch) before germination were immersed for 1 hour. After washing the carrot seeds with water and air-drying, a plastic vat (30 x 45
Diluvial soil was put in cm ² and height 6 cm), and 20 grains of each treatment area were sown and covered with soil. I went in two cycles. After germination in a greenhouse, the germination rate was examined 10 days after sowing. The results are shown in Table 3.

[0015]

[Table 3]

Claims (4)

[Claims] 1. A method for promoting germination and initial growth of plant seeds, which comprises treating an ungerminated plant seed with an effective amount of paclobutrazol. 2. The method according to claim 1, wherein the ungerminated plant seeds are immersed in an aqueous solution of paclobutrazol. 3. The concentration of the aqueous solution of paclobutrazol is 0.
The method according to claim 1, which is from 01 to 1000 ppb. 4. The method according to claim 1, wherein the plant seed is rice.