JPS6176402A - Method for increasing the yield of gramineous crops - Google Patents

Abstract

PURPOSE:To increase the yield of gramineous crops such as wheat and corn, by using brassinolide, widely distributed in the vegetable kingdom and exhibiting various kinds of biological effects, as an yield-increasing agent and applying it during the blooming and ripening period of the gramineous crops. CONSTITUTION:To device the yield increase by using (2alpha,3alpha,22R,23R)-tetrahydroxy-24S-methyl-B-homo-7-oxa--5alpha-- cholestan-6-one, i.e. brassinolide, expressed by the formula for treating whole or a part of the gramineous crop such as flowers, leaves, stems, roots, fruits and ears during its blooming and ripening period. As for a treating method, a method suitable for treating each objective part such as spraying, dipping and coating may be adopted. The concentration of the brassinolide is pref. about 10<-1>-10<-3>ppm for the wheat, and its frequency of treatment is pref. 1-5 times when the concentration is 10<-2>ppm.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides (2α, 3α, 22R', 23R)-tetrahydroxy-248-methyl-B-homo-7-oxa-5α-cholestane-6-oznawati represented by the formula -H. , relates to a method for increasing the yield of grass crops using brassinolide, and a crop yield increasing agent used therein.

More specifically, the present invention provides a method for increasing the yield of gramineous crops such as rice, wheat, and corn, which comprises treating the crops with brassinolide during the flowering and ripening stage, and the method. Concerning crop yield enhancers to be used.

Brassinolide is a steroidal plant growth regulator whose structure was isolated from Brassica napus flowers in 1979 [Nature, Vol. 281゜P21
6-217. (1979)]. Many steroids are known as animal and insect hormones, but brassinolide is the first steroidal substance found to exhibit physiological activity in plants. Brassinolide is considered to be the sixth plant hormone, following ethylene, auxin, gibberellin, cytokinin, and absyric acid, and academic research is progressing on its distribution and function in plants. It is being

The effects of brassinolide on living organisms have been evaluated by comparison with other plant hormones using various bioassay methods, including the second internode elongation test for kidney beans, the rice lamina joint test, and the raphanus test for radish. Tests were conducted (Chemical Regulation of Plants, Vol. 18, No. 1, 38~
54, p. 1, 1983) Taken together, brassinolide has attracted attention because it exhibits unique activities different from other plant hormones. In addition, it showed a strong synergistic effect on auxin in a plant elongation test, and a synergistic effect on cytokinin in a callus growth test.
“It exhibits remarkable effects that cannot be seen when used alone.

In addition to brassinolide, more than 10 analogues have already been discovered in plants, and these brassinolides include rice, kidney beans, Chinese cabbage, tea, chestnut, Fuji pea, pine, cattail, etc. It has been confirmed that it is widely included in higher plants such as Isutuki.

The present inventors began research on the use of brassinolide, which is widely distributed in the plant kingdom and exhibits diverse biological effects, from a practical standpoint. The present inventors have discovered that an effect of increasing yield can be obtained when used in the treatment of , and have completed the present invention.

Conventionally, regarding the effects of brassinolide on plants, an example of brushing with a crude extract from the pollen of Brassica napus (K., 7, y, Mitchell et al.
Ll and L, Gregory, Natu
re New Biology, 239. P2S5.
1972), Examples of radish, lettuce, green beans, koshiyo, and potatoes using the synthetic related compound brassinosteroid (5science, yol, 212. P33
~34.1981) is known. In the case of brushing, lanolin paste is applied to seedlings of kidney beans, and in the case of brassinosteroids, an aqueous solution is sprayed on the seedlings.

Furthermore, in JP-A No. 57-118503, homobrassinolide, a synthetic compound of brassinolide analogs, is used in tomatoes, carrots, daikon radish, radish, cucumber,
It has been disclosed that a growth promoting effect can be brought about by soaking and tilling the seeds or young seedlings of azuki beans. Furthermore, the same patent publication states that homobrassinolide exhibits a growth-promoting effect when seed potatoes, sweet potato seedlings, tea cuttings, and tobacco seeds are cultivated after soaking, and also improves the flowering of fruit trees. It has been shown that fruit diameter and fruit weight increase by spraying during the season.

Although these examples are tests using crude extracts or synthesized brassinolide analogues, the present inventors have specifically found that using brassinolide, an effect of increasing crop yield can be obtained. , completed the invention.

The present invention will be explained in detail below. The present inventors treated wheat with brassinolide at each growth stage and examined the effects on the growth process of wheat. As a result, in plots sprayed from the tillering stage, as the brassinolide concentration increased, the tiller panicle weight and main stem panicle weight decreased significantly.

In addition, in plots where spraying was applied from the middle stage of unsettled differentiation, the tiller weight decreased, but no change was observed in the main stem weight. However, in the plots where it was sprayed from the beginning of flowering, both tiller panicle weight and main stem panicle weight clearly increased compared to the untreated plots, and the fruiting rate of weak florets improved. In addition, regarding grain weight, the weight per fruit at the winter-sewn position, the weight of each fruit per unsteadiness, and the total weight of the grains at upper, middle, and lower restlessness all clearly increased.

The total weight of the fruit reached the maximum in the case of the 110-2 pp treatment, which was an increase of 10 inches compared to the untreated one. The increase in the weight of the fruit due to the treatment was particularly remarkable in the weakly hot and restless fruit.

As mentioned above, treatment with brassinolide before the flowering stage has a disadvantageous effect on 1d fertile fruit and yield, but treatment with brassinolide during the flowering fertile stage particularly improves the fruit set rate of low-heat florets and reduces low-heat florets. It was found that this resulted in increased yield through an increase in fruit weight.

In this way, the fact that the fruiting rate is usually low and the fruit weight is low can be increased by treatment with brassinolide during the specific period of flowering and fertile fruiting.The reason for the increase in yield is clear, so it is extremely practical. This can be said to be significant.

The method for increasing the yield of gramineous crops of the present invention involves removing part or all of the gramineous crops such as rice, wheat, corn, etc., such as flowers, leaves, stems, roots, fruits, and ears, during the flowering and ripening stages of the gramineous crops such as rice, wheat, and corn. This is done by processing the Therefore, a method suitable for treating each area, such as spraying, dipping, or coating, is adopted as the treatment method.

The concentration of brassinolide varies depending on the processing method and type of crop, but in the case of wheat, it is practically preferable to spray it over the entire surface, and in that case, a range of 0-1 to io'ppm is recommended. .

The number of times of brassinolide treatment varies depending on the treatment method, type of crop, and concentration used, but when spraying brassinolide at a concentration of 110-2 pp, it is usually carried out within the range of 1 to 5 times.

The mechanism by which this yield-increasing effect occurs is currently unknown, but according to experiments conducted by the present inventors, the rate of photosynthesis,
It has been found that stomatal conductance (gs) and mesophyll conductivity (gm) have a somewhat promoting effect on growth strategies, but rather have a suppressive effect on aging leaves. Both gS and gm are 1 for the change in photosynthetic rate due to brassinolide treatment.
(It seems that they are involved.

Brassinolyte r used in the present invention is synthesized by, for example, the synthesis method of Mori et al. (Agric, Biol, Chem, 4).
7(3)663-664.1983).

Brassinolide used in the method of the present invention can be formulated into various dosage forms and used. For example, solid dosage forms such as powders, granules, tablets, irrigation agents, and water solutions using mineral materials such as clay, bentonite, talc, diatomaceous materials, etc., or emulsions and solutions using water or organic solvents. Liquid dosage forms such as or petrolatum,
It is used as a disinfectant using lanolin and the like.

Examples of organic solvents used include acetone, methanol, ethanol, dimethylformamide, ethylene glycol, ethyl acetate, toluene, and xylene.

In addition, in order to improve the wet spreadability, permeability, dispersibility, adhesion, fixation, suspension, etc. of each of the above dosage forms, Nonionic surfactants such as ethers and polyoxyethylene resin esters; anionic surfactants such as sodium dinaphthylmethane disulfonate, sodium ligninsulfonate, and sodium dodecylbenzenesulfonate; 1. Auxiliary agents such as e-roughin and D-sorbitol can be used.

The amount of brassinolide to be contained in the pharmaceutical dosage form used in the method of the present invention can be determined as appropriate depending on each dosage form, the type of crop to be applied, and the application method. Usually, when spraying, an acetone or ethanol solution with a concentration of about 10 to 1000 ppm is prepared, and this is preferably diluted with water to an active ingredient concentration of 10-1 to 10-''ppm and 8 degrees.

Further, when spraying the brassinolide aqueous solution, it is possible to use the conventional amount of water, and when treating a large area, it is also possible to spray a small amount by aircraft.

lO- In the above dosage form, other plant hormones, fertilizer components, herbicides, fungicides, insecticides, etc. may be mixed and used as required.

Brassinolide is a natural product that is widely contained in various plants eaten by humans, so it can be said that there are no problems with its safety and biodegradability.

The present invention will be explained in more detail below using manufacturing examples, tests, and measurements of the dosage forms used, but it goes without saying that the present invention is not limited thereto.

Formulation Example 1 (Liquid) 1001g of Brassinolide and 10yll of Neoesterin (spreading agent made by Kumiai Chemical Co., Ltd.) mixed with ethyl alcohol 990+
Prepare by dissolving in xl and mixing uniformly. When using, dilute 1,000 to 1,000,000 times with water.

Formulation Example 2 (Emulsion) Brassinolide 0.01 parts by weight Dimethylformamide 60 parts by weight Xylene
Prepared by uniformly mixing 10 parts by weight of 30 Jutsubu Nitten (Bj! chemical spreading agent).

Formulation Example 3 (Wettable powder) Brassinolide: 0.1 parts Diatomaceous solution: 85 parts Polyvinyl alcohol: 5 parts Dodecylbenzenesulfonic acid sorta: 9.9 parts are mixed and ground thoroughly.

Formulation Example 4 (Paste) Brassinolide 0.001 parts Ethyl alcohol 10 parts Lanolin
Prepare by uniformly mixing 90 parts.

Test Example 1 A test was conducted using Asakaze wheat according to the method shown in Table 1.

A 10 (1 ppm) ethyl alcohol solution of brassinolide was diluted with a 5000 times aqueous solution of neoesterin.
Sufficient amounts were applied to the whole wheat at three concentration levels of 0-4.10-2.10 ppm. Cultivation management was carried out as usual, and post-harvest yield surveys were conducted for test plots ■, ■, and ■.

The investigation included (1) Effects on initial growth of germination, (2) Effects on tillering, (3) Effects on heading, (4) Effects on panicle weight, and (5) Effects on fertility of main stem panicles. 5
I have started implementing the items.

The test results for each item are shown below. The Roman numerals in the figure represent the test numbers in Table 1. In addition, in the explanation of the figures, brassinolide is abbreviated as BR.

Table 1 Test method results (1) Effect on early growth after germination At concentrations of 10-2 and 10 ppm, elongation of coleoptiles and roots was strongly suppressed, but the number of plates slightly increased.

(2) Effect on tillering test In ■ and ■, as the concentration of brassinolide increased, the number of tillers increased, but the effective stalk ratio decreased, and therefore the effective number of stalks decreased.

(3) Effect test on heading TT In IC, brassinolide treatment showed the effect of delaying the heading period.

(4) In the effect test on electrical connection■, as the concentration of brassinolide increases,
Both tiller electrical conductivity and main stem electrical conductivity decreased significantly. In test ■, the tiller contact voltage decreased due to the treatment, but no change was observed in the main stem contact voltage. In Test and Test ■, both tiller electrical contact and main stem electrical contact clearly increased due to the treatment.

(5) Effect on the fertility of main stem panicles In test (2), brassinolide treatment improved the fruiting rate of weakly heated florets. The weight per 11 heads of each seedling position, the weight of each crop per 11th seedling, and the total weight of the top, middle, and lower ears increased. The maximum hearing weight was achieved with the 10-2 ppm treatment, which was an increase of 10 inches compared to the untreated sample. The increase in the amount of electricity produced by brassinolide treatment is particularly remarkable in heading and fruiting under low heat.

[Brief explanation of the drawing]

1 and 2 are graphs showing the test results for confirming the effects of the present invention in one embodiment of the present invention, and both of them are graphs showing the results of tests regarding electrical connection in Test Example 1 described in this specification. It is a graph showing the effect of the invention method. Figure 1 (A) shows test ■, (B) shows test ■, (
C) shows the results of test ■, in which the left vertical axis is the total electrical contact per pot (li'/pot), and the right vertical axis is the split electrical contact or main stem electrical connection per pot (7/pot).
), the treatment concentration of horizontal dinolide ('pprn
) is shown. The symbols in the figure have the following meanings.・−−→ Total electrical contact Δ−−−−mu Main stem electrical power 0−−→ Tiller electrical contact The values in parentheses are relative values with the untreated area as /θ0 Figure 2 (A-), (B ), (C), and Figures 3 to 5 all show the results of the efficacy test on Brassinorrhea on the fertile seeds of the main stem panicle in Test ■, and (A) shows the results of the efficacy test on Brassinorrhea on the fertile seeds of the panicle of the main stem in Test ■.
B) shows the relationship between the weight per fruit and the top floret fruiting rate and the treatment concentration for the middle heading and (C) the lower heading. In both cases, the left vertical axis is the weight per fruit Cm9”)C
G, W, ), the right vertical axis is the top floret fruiting rate (G, S
), the horizontal axis indicates the brassinolide treatment concentration (ppm). Figure 3 shows the amount of electric power per spikelet relative to the brassinolide treatment concentration, Figure 4 shows the same, electric power per ear (ratio) is 1, and Figure 5 shows the same, upper, middle, and lower. This shows the relationship between the production of rice and the arrival of rice. Figure 3, the vertical axis is
In the figure, the vertical axis shows heading yield (ratio), the vertical axis shows the upper, middle, and lower heading yield (m9), and the horizontal axis shows the brassinolide treatment concentration (ppm). ) is shown. In this figure, the upper ear is the third ear counting from the top ear, the lower ear is the third ear counting from the base/J-ear, and the position of the ear on the ear is with a at the base. , below towards the top bSc.

Claims (3)

[Claims] (1) At the flowering and fertile stage, grass crops are expressed by the formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ 1. A method for increasing the yield of gramineous crops, comprising treating them with 7-oxa-5α-cholestan-6-one. (2) The method for increasing the yield of a gramineous crop according to claim 1, wherein the gramineous crop is wheat. (3) The method for increasing the yield of a gramineous crop according to claim 1, wherein the gramineous crop is corn.