A plant growth regulator for promoting rice seed filling and its use method and application

Abstract

The application discloses a plant growth regulator for promoting rice seed setting and filling, and a use method and application thereof, wherein an effective component of the plant growth regulator is naphthalene acetic acid, a fungicide and leucine; according to a use concentration, the naphthalene acetic acid is 10-50 micromoles per liter, the volume percentage concentration of the fungicide is 0.1-0.5%, and the mass percentage concentration of the leucine is 0.1-0.5%. The fungicide is rice clear. When in use, a mixed aqueous solution of the plant growth regulator is used for spraying on a rice leaf surface and a rice ear, and is sprayed at a rice flowering period and a seed filling middle period respectively. The plant growth regulator for promoting rice seed setting and filling can promote rice seed setting and filling, can improve a seed setting rate and a grain weight, and can increase a rice yield.

Description

Technical Field

[0001] This invention relates to the field of plant growth regulators, and in particular to a plant growth regulator that promotes grain filling and ripening in rice, as well as its application and usage. Background Technology

[0002] The grain filling rate of rice is a crucial factor in yield, primarily determined by flowering and fertilization, and grain filling. The flowering and fertilization process begins with the splitting of the anthers of the stamens, transferring pollen grains to the stigma of the pistil. The pollen grains then germinate, and the pollen tube elongates, entering the stigma, passing through the style, and reaching the ovary and ovule. There, the pollen carries a pair of sperm cells into the embryo sac, fertilizing the egg cell and the central cell, respectively. After fertilization, the ovary continuously swells and fills, the endosperm cells proliferate, accumulate and store starch, and the grains fill and develop into caryopsis. The quality of fertilization during flowering determines the number of empty grains on the spikelet, while the degree of grain filling affects both the number of shriveled grains and grain weight, both ultimately determining the rice yield.

[0003] The fertilization and grain-filling period is a time when rice is highly sensitive to environmental factors such as water and temperature. Unfavorable environmental factors at this time can affect the grain-filling rate of spikelets by influencing floret dehiscence, pollen fertility, and pollen tube germination and elongation. Environmental factors during the grain-filling period mainly affect the proliferation rate of endosperm cells, thus influencing the degree of grain filling and determining not only yield but also rice quality by affecting the accumulation and arrangement of starch granules. For example, drought stress during the flowering and grain-filling period can delay heading, reduce pollen germination rate, increase the number of degenerated florets, decrease the number of grains per spike, reduce grain weight, and worsen rice quality. High temperatures above 35℃ during the flowering period can reduce the grain-filling rate of rice varieties to about 55%, resulting in a yield reduction of 160 kg / mu. The main mechanisms include high temperatures inhibiting anther dehiscence, stigma pollen germination, and pollen tube elongation in the pistil tissue, leading to spikelet abortion, increased empty grains, and a reduced grain-filling rate.

[0004] Studies have found that nitrogen application, especially during the flowering and grain-filling stage, can improve the nutritional status of rice in the later stages of growth, delay the senescence of functional leaves, increase grain sink capacity and activity, coordinate the balance among nitrogen sources, sinks, and runoff, increase or decrease the proportion of photosynthetic products per unit grain sink capacity, and enhance the physiological activity of grain filling. Some studies suggest that moderate soil drought after rice heading and flowering is beneficial for improving photosynthesis in the flag leaf, increasing the accumulation of assimilates, and influencing the activity of key enzymes in the starch synthesis pathway by regulating the balance of certain hormones in the plant, thereby promoting the filling of grains with grain-filling substances. Compared to traditional water and fertilizer management methods, spraying chemical regulators is timely and efficient, making it one of the most effective measures for regulating the physiological activity of rice grain filling and coping with unpredictable environmental stresses. Therefore, providing a plant growth regulator that synergistically promotes rice grain filling has become a pressing goal for the industry. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a plant growth regulator that can synergistically promote grain filling and grain filling in rice, as well as its method of use and application.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] On the one hand, the present invention provides a plant growth regulator for promoting grain filling in rice, the active ingredients being naphthaleneacetic acid (NAA), a fungicide, and leucine (LEC). Calculated by the concentration used, the NAA is 10-50 μmol / L, the fungicide is 0.1-0.5% by volume, and the leucine is 0.1-0.5% by mass.

[0008] Furthermore, the fungicide is rice fungicide.

[0009] Furthermore, the active ingredient content of the rice extract is 9% pyraclostrobin.

[0010] Further, the naphthaleneacetic acid is 10-20 μmol / L, the bactericide has a volume percentage concentration of 0.1-0.22%, and the leucine has a mass percentage concentration of 0.1-0.2%.

[0011] Furthermore, the naphthaleneacetic acid concentration is 10 μmol / L, the bactericide concentration is 0.1% by volume, and the leucine concentration is 0.1% by mass.

[0012] Alternatively, the naphthaleneacetic acid concentration is 20 μmol / L, the bactericide concentration is 0.2-0.22% by volume, and the leucine concentration is 0.2% by mass.

[0013] Furthermore, the plant growth regulator also contains adjuvants to formulate a dosage form suitable for agricultural use.

[0014] Secondly, the present invention also provides a method for using the above-mentioned plant growth regulator for promoting rice grain filling, wherein the mixed aqueous solution of the plant growth regulator is used for foliar spraying and panicle spraying on rice, respectively during the flowering period and the middle stage of grain filling.

[0015] Thirdly, the present invention also provides an application of the above-mentioned plant growth regulator for promoting rice grain filling, wherein the application is used to promote rice grain filling and grain development, increase grain filling rate and grain weight, and increase rice yield.

[0016] By adopting the above technical solution, the present invention has at least the following beneficial effects:

[0017] (1) This invention has found through research that the ternary compound combination of plant growth regulator naphthaleneacetic acid, fungicide rice chlorine and leucine has a significant effect on rice seed setting during flowering and grain filling during the late heading stage. This invention screened the optimal application concentration range of this compound combination. Under this concentration combination, rice grain setting and filling are significantly improved, material translocation rate is significantly increased, seed setting rate and grain weight are significantly increased, and yield is significantly increased.

[0018] (2) The plant growth regulator of the present invention can be widely used in rice production to promote grain filling, increase the grain filling rate and grain weight, and improve yield. Its significance lies not only in its application to varieties that are widely used in production to improve their grain filling, but also in its important reference value for hybrid seed production with low grain filling rate. Detailed Implementation

[0019] This invention relates to a plant growth regulator for promoting rice grain filling and ripening, primarily used to promote grain filling and ripening, increase grain filling rate and weight, and ultimately increase rice yield. Its active ingredients are naphthaleneacetic acid (NAA), a fungicide, and leucine, forming a ternary compound composition. NAA acts as a plant growth regulator, the fungicide primarily functions as a bactericide, and leucine is an amino acid nutrient. Based on the concentration used, NAA is 10-50 μmol / L, the fungicide is 0.1-0.5% by volume, and the leucine is 0.1-0.5% by mass. As a preferred embodiment, the fungicide is selected from Daoqing (BASF China Co., Ltd.), which contains 9% pyraclostrobin as its active ingredient. More preferably, NAA is 10-20 μmol / L, the fungicide is 0.1-0.22% by volume, and the leucine is 0.1-0.2% by mass.

[0020] The recommended concentration for use is as follows:

[0021] Naphthaleneacetic acid: 3.724 mg dissolved in 1 L of water (1000 g of water), i.e., the concentration is 20 μmol / L;

[0022] Daoqing (active ingredient is 9% pyraclostrobin): 0.22ml dissolved in 100mL of water, i.e., volume percentage concentration is 0.22%;

[0023] Leucine: 0.2g dissolved in 100mL of water (100g of water) has a mass percentage concentration of 0.2%.

[0024] In addition to the active ingredient, the aforementioned plant growth regulators may also contain adjuvants to formulate formulations suitable for agricultural use. Examples include commonly used wettable powders, water-dispersible granules, microemulsions, emulsions, emulsifiable concentrates, suspensions, or granules. This embodiment preferably uses water-dispersible granules.

[0025] When used in the field, the mixed aqueous solution of plant growth regulator is applied to the leaves and ears of rice, respectively, during the flowering period and the middle of the grain filling stage (20 days after flowering), by spraying; the amount of liquid to be sprayed per acre is 30 liters, and the leaves and ears are sprayed evenly.

[0026] The following detailed description is provided through examples:

[0027] 2021-2022, Experimental Field of China National Rice Research Institute, Fuyang City, Zhejiang Province. The tested rice varieties were Chunyou 927 and Yongyou 7860, large-panicle hybrid indica-japonica rice with a high grain-to-palm number. The rice was sprayed twice, once during flowering and once during mid-grain-filling, with the following concentrations: 20 μmol / L naphthaleneacetic acid, 0.22% BASF rice extract, and 0.2% leucine.

[0028] The tested varieties flowered from September 5th to 10th. During the flowering period and mid-grain filling period from September 25th to 30th, various concentrations of naphthaleneacetic acid, isopyridine, leucine, and their compound formulations were sprayed. Samples were taken every other day to analyze their effects on the physiological indicators of rice leaves. The yield and its composition changes under each treatment were also measured at harvest.

[0029] Table 1 shows the yield changes of rice variety C Liangyou Huazhan under different concentrations of naphthaleneacetic acid (NAA) and leucine spray. The results indicate that spraying either NAA or leucine alone can increase rice yield, with the effect varying depending on the spray concentration. Specifically, NAA at a concentration of 20 μmol / L increased rice yield by 4.31%; while leucine (0.22% by volume) also had a certain yield-increasing effect, with an increase of approximately 4.08%. Furthermore, spraying leucine alone had a relatively small impact on rice yield.

[0030] Table 1. Effects of naphthaleneacetic acid (NAA) spraying on rice yield (2021)

[0031]

[0032] The same letter in the same column indicates that there is no significant difference at the 5% level.

[0033] Based on the results of single-component concentration spraying experiments, 20 μmol / L naphthaleneacetic acid (NAA), 0.22% isopyridine (v / v), and 0.2% leucine (m / m) were selected for compound experiments. Table 2 shows the changes in rice yield under different compound combinations of spraying agents. The results showed that spraying NAA + isopyridine could increase rice yield, with average yield increases of 5.88% and 5.22% for Chunyou 927 and Yongyou 7860, respectively; while spraying the compound of NAA + isopyridine + leucine significantly increased rice yield, with an increase of approximately 7.66%-11.17%.

[0034] Table 2. Effects of spraying naphthaleneacetic acid and rice extract combined on rice yield (2021)

[0035]

[0036] Within the same column and for the same variety, different letters indicate significant differences between treatments at the 5% level.

[0037] From the perspective of yield composition, the combined application of naphthaleneacetic acid, isopyridine, and leucine had no significant effect on the number of panicles and grains per panicle in rice, but it significantly increased the seed setting rate and grain weight, thereby significantly increasing the yield by 10.29%-11.34% (Table 3). The effects of the pesticide treatments on the number of pollen grains and germination rate of rice stigmas were determined. The results showed that after spraying the combined application of naphthaleneacetic acid, isopyridine, and leucine, the number of pollen grains on the stigmas of rice florets significantly increased, and the pollen grain germination rate significantly improved (Table 4). This indicates that the increase in the number of pollen grains and the pollen germination rate after spraying the combined pesticides effectively promoted the success rate of rice fertilization and seed setting, thereby increasing the seed setting rate and ultimately significantly increasing the yield.

[0038] Table 3. Effects of the combination of naphthaleneacetic acid, isopyridine, and leucine on rice yield composition (2022)

[0039]

[0040] Different letters for the same variety in the same column indicate significant differences between treatments at the 0.05 level; the same applies to the following table.

[0041] Table 4. Effects of spraying naphthaleneacetic acid, isopyridine, and leucine on the number of pollen grains and germination rate of rice spikelets in 2022.

[0042]

[0043] Measurements of various physiological indicators in rice leaves showed that spraying a compound of naphthaleneacetic acid (NAA), oreganoic acid, and leucine significantly increased chlorophyll content and photosynthetic rate in the later stages of grain filling, while decreasing malondialdehyde (MDA) and hydrogen peroxide content (Table 5). The increased chlorophyll content during the grain filling stage indicates a reduced degree of leaf senescence, thus helping to maintain a higher net photosynthetic rate, produce more photosynthetic assimilates, and promote the accumulation of carbohydrates during grain filling. The decreased content of MDA and hydrogen peroxide, products of membrane lipid peroxidation damage, indicates that spraying a compound of NAA, oreganoic acid, and leucine can effectively alleviate the decline in physiological activity of plant leaf organs in the later stages of grain filling, improve photosynthetic and other physiological metabolism, and increase assimilate accumulation. With sufficient "source" (nutrients), grain filling proceeds smoothly, resulting in increased seed setting rate, grain weight, and yield.

[0044] Table 5 Effects of spraying naphthaleneacetic acid, isopyridine and leucine on physiological indicators of rice leaves (2022)

[0045]

[0046] Further investigation was conducted into the optimal spraying concentration of the compound naphthaleneacetic acid, isopyridine, and leucine. The results are shown in Table 6 below.

[0047] Table 6. Effects of different concentrations of naphthaleneacetic acid and isopyrazine compound spray on rice yield (2022)

[0048]

[0049] Table 6 shows that different concentrations of the compound application of naphthaleneacetic acid (NAA), isopyram, and leucine have varying effects on rice yield. 10-50 μmol / L NAA, 0.1-0.5% isopyram, and 0.1-0.5% leucine all significantly increased yield, with increases ranging from 8.9% to 12.6%. The compound combination of "10 μmol / L NAA + 0.1% isopyram + 0.1% leucine" showed the greatest yield increase, at 11.4-12.6%.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, equivalent changes, or alterations made by those skilled in the art using the disclosed technical content shall fall within the protection scope of the present invention.

Claims

1. A plant growth regulator that promotes grain filling and ripening in rice, characterized in that, The active ingredients are naphthaleneacetic acid (NAA), a bactericide, and leucine. Based on the concentration used, NAA is 10-50 μmol / L, the bactericide is 0.1-0.5% by volume, and the leucine is 0.1-0.5% by mass. The active ingredient content of the fungicide is 9% pyraclostrobin.

2. The plant growth regulator for promoting grain filling in rice according to claim 1, characterized in that, The naphthaleneacetic acid concentration is 10-20 μmol / L, the bactericide concentration is 0.1-0.22% by volume, and the leucine concentration is 0.1-0.2% by mass.

3. The plant growth regulator for promoting grain filling in rice according to claim 2, characterized in that, The naphthaleneacetic acid concentration is 10 μmol / L, the bactericide concentration is 0.1% by volume, and the leucine concentration is 0.1% by mass. Alternatively, the naphthaleneacetic acid is 20 μmol / L, the bactericide has a volume percentage concentration of 0.2-0.22%, and the leucine has a mass percentage concentration of 0.2%.

4. The plant growth regulator for promoting grain filling in rice according to any one of claims 1-3, characterized in that, The plant growth regulator also contains adjuvants to formulate a dosage form suitable for agricultural use.

5. A method of using the plant growth regulator for promoting grain filling in rice as described in any one of claims 1-4, characterized in that, The mixed aqueous solution of the plant growth regulator is used for foliar and panicle spraying of rice, applied during the flowering period and mid-grain filling period of rice, respectively.

6. The application of a plant growth regulator for promoting grain filling in rice as described in any one of claims 1-4, characterized in that, It is used to promote rice grain filling and grain filling, increase grain filling rate and grain weight, and increase rice yield.

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