JPS62146537A - Culture of puddy rice - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Industrial application field] This invention relates to a method of cultivating rice.

[Conventional technology]

Generally, rice cultivation in Japan begins with the selection of rice seeds in the spring, followed by sowing, germination, transplanting, and harvesting in the fall. During this period, rice transplanted to cultivated land, such as rice fields, goes through the rooting stage, nine tillering stage, the panicle formation stage, and the heading stage.

It grows and bears fruit through the flowering stage and full ripening stage.

[Problem that the invention seeks to solve]

In rice cultivation, the factor that determines the yield per R-planted area is the number of ears per unit planted area.

■There are four points: number of paddy per ear, ripening ratio of paddy, and weight per 1,000 grains of brown rice. The number of panicles per unit area is determined by the number of rice grains that form panicles per unit cultivated area,
In other words, it is the number of valid votes.

When transplanting seedlings, several bacteria are treated as one strain.

Since rice is planted at regular intervals on cultivated land, the number of effective tiller votes per unit cropped area is the product of the number of rice plants per unit cultivated area and the number of effective tiller votes per rice plant. however,
From these calculations.

Simply increase the number of plants per unit acreage.

Increasing the number of rice plants per plant not only does not increase the number of effective tillers, but also weakens the rice plants, as the growing environment deteriorates due to overcrowding.

As rice plants grow from seedlings, stalks grow by dividing from the nodes of the parent stalk, and secondary divisions also occur from the dividing stalks. Good rice plants are divided from the lower nodes of the parent stem, and secondary division from the stem is also active.

The division of rice begins shortly after transplanting and after the rooting period has passed, and the number of votes gradually increases as the rice grows. and,
The number of votes reaches its highest a few days before reaching the panicle differentiation stage, after which some of the stems die without producing panicles, and the remaining stems produce panicles.
ripen.

The latter stems that produce ears are called effective tillers, and the former stems that wither and die without producing ears are called ineffective tillers.

For example, when cultivating Koshihikari in the paddy fields downstream of Toneyo, a rice farm in the Kanto region, the tillering period usually reaches its peak around 45 days after transplanting the seedlings.

In so-called 4-planted plants, each plant has 4 parent stems.
The number of votes will be around 20. After that, during the panicle differentiation stage, about 20% of the above votes die as invalid tillers, and the remaining 16 plants set ears.

Another problem in rice cultivation is lodging of rice during the full ripening stage. Lodging rice plants not only make harvesting difficult, but also cause various problems. [The more ears the iB produces and the higher the rate of ripening, the more likely the rice will lodge;
Varieties such as Koshihikari and Sazanishiki are especially prone to lodging. Lodging of rice plants is related to stem thickness and internodal distance.

Rice is said to be less likely to lodge if it is exposed to sufficient sunlight during the growing period, avoiding overcrowding and excessive nitrogen fertilizers.

In the current situation of conventional rice cultivation, the inventor of the present invention aimed at unit cropping in order to obtain a larger harvest per area, without reducing the number of paddy per ear, and to secure a larger number of effective tiller votes. They also considered whether it was possible to grow rice that was durable and resistant to lodging. This invention was achieved as a result of the above studies.

[Means to solve the problem]

That is, in the cultivation of rice from planting to harvest, this invention usually involves cultivating rice during at least one of the hours after sunset or before sunrise for several days to several tens of days before the rice reaches its maximum tillering stage. It irradiates the rice with light.

〔Example〕

Next, examples of the present invention will be described together with comparative examples, and desirable embodiments will also be described.

The table below shows the rice fields in Shintone Village, Inashiki District, Ibaraki Prefecture.
After transplanting the Koshihikari seedlings sown on March 15th on May 5th, the method according to the present invention and the conventional method were carried out.
This is a record of experimental cultivation of rice under the same conditions. There are 4 seedlings
Book planting binding.

The number of votes indicates the average number of votes per share. Also.

The total length was the average length from the root to the tip of the rice plant. In the remarks column, (al) indicates the example, and (b) indicates the comparative example.

The relationship between February date and the number of votes is also shown in the graph in Figure 1.

5/25 12 pieces 25cm 12 pieces 25cm15
36 45 3G 45 (a) Irradiation start 25 40 55 40 55 (bl highest division 7/1 40 65 40 65
10 50 70 33 70 (bl
Young ears confirmed 25 90 102 32 102 (
bl Earing start 30 104 i05 32
1058/1 104 110 32 110
ta+irradiation stop 15101 120 32 120
(al young panicle confirmation 915 101 130 32
130 (bl reaping 1015 tot
130 (al reaping may 5
Seedlings transplanted into rice fields on a daily basis are divided as they grow, starting with four parent stems per plant.

The number of votes continued to increase from 12 to 15 to 25, reaching an average of 40 votes between June 20th and July 10th. This is the peak tillering period for normal rice.

In this invention, light irradiation is started on the rice plants several days before reaching the highest tillering stage. For example, in the example, irradiation started on June 15th. Light is applied for several hours at least either before sunrise or after sunset. In the case of the example, irradiation was carried out for an average of 10 hours every day from sunset until sunrise. The best light to irradiate is from a fluorescent lamp.For example, using a typical daylight-colored fluorescent lamp, 40 m of cultivated land
Aim for the brightness of one W fluorescent lamp.

After that, in the comparative rice plants that were not irradiated with light, about 20% of tillers died after the maximum tillering stage, and the number of votes was about 3.
Now there are two. Next, young panicles can be seen around July 10th, 10 to 20 days after the maximum tillering period, and then 20 to 20 days from now.
Earing started around July 30th, ~25 days later. and 8
The ears were harvested around September 5th and harvested on September 5th. The average height of the rice plants at that time was 115 cm, and the number of stalks with ears, that is, the number of effective tillers, was 32 per plant.

On the other hand, in the example in which light was irradiated, the tillering of rice continued even after the maximum tillering period of double characters, and the number of votes continued to increase. That is.

After starting the light irradiation on June 15th, the number of votes was 4 on the 20th.
The number of votes continued to increase until August 1, when the light irradiation was stopped, reaching a maximum of 104.

During this period, no young panicles were observed.

After that, several percent of the tillers die and become so-called invalid tillers, but after stopping the irradiation with light, one
Young ears were confirmed four days later on August 15th, and heading started on August 30th. Next, on September 5th, the grains were ready, and on October 5th,
I was able to reap it in a day. The total length of the rice plant when harvested was 130c+n.

The number of stems with ears, ie, the number of valid tillers, was 101. That is, an average of three stems per plant were ineffective tillers.

The fact that 3-tillation progresses in sea urchins when irradiated with light and the panicles are not seen until the irradiation is stopped is 9.
This means that by continuing to irradiate the grain with light until a certain number of tiller votes are obtained, panicle differentiation can be suppressed and two tillers can be maintained. However, it depends on each region.

Although it is natural that there is a limit to the timing of ear differentiation that can be delayed due to the climate, it is possible to control the timing of rice heading to a certain extent within the range allowed by such environmental conditions. At the time of heading, after the light irradiation is stopped,
Aim for around 30 days.

Next, in each of the Examples and Comparative Examples, 10 harvested rice plants were randomly sampled, and the number of rice grains attached to each ear, that is, the number of grains per grain, was determined. As a result, the distribution of the number of grains set on each ear per plant was as shown in the table below.

Around 120 grains 10 pieces Around 120 grains 4 pieces 100
〃21〃100〃8〃 80 〃30〃 )(0〃 12〃70〃
35〃70〃15〃65〃5〃65〃2〃In the example, 101 stems per plant produced ears, and in the comparative example,
There are 32 stalks with ears, but the distribution of the number of grains per seed is 9.
Both are generally the same, and therefore, in the example, the number of rice grains per plant was about three times that of the comparative example.

Furthermore, when the appearance of the harvested rice was compared, there was no significant difference in the total length of the rice in both Examples and Comparative Examples, but the rice in the Examples all had thicker stems than the rice in the Comparative Examples. Also,
The parent stem of the latter rice had all five nodes, while the parent stem of the former rice had six nodes, and the internodal distance was shorter than that of the latter rice. . Due to these differences,
Although the former rice had a higher number of grains set than the latter, there was no lodging at the full ripening stage.

〔Effect of the invention〕

As explained above, according to the present invention, f! It is possible to secure a large number of effective tillers with an I mark, and also to cultivate one case of rice in an inverted manner.

Effects such as being able to artificially delay the heading period can also be obtained.

[Brief explanation of drawings]

Figure 1 is a graph showing the change in the number of votes from rice seedling transfer to reaping for the examples and comparative examples of the present invention. It is a drawing showing the state of a stem. Inventor and patent applicant Masao Matsuura Attorney Kazuyoshi Hojo Ura

Claims (1)

[Claims] During rice cultivation, from transplanting seedlings to harvest, the rice is exposed to light for at least one of the hours after sunset or before sunrise for several days to several tens of days before the rice reaches its highest tillering stage. A method of cultivating rice characterized by irradiation.