Use of a gibberellic acid (ga3) containing stimulator in increasing yield and quality of kiwifruit

Abstract

The application provides a use of a GA3-containing accelerating agent in improving yield and quality of kiwifruit, and belongs to the technical field of fruit tree cultivation. The application provides application of GA3 in improving yield and quality of kiwifruit, wherein the working concentration of the GA3 is 50-100 mg / L. The application also provides a GA3-containing accelerating agent. As shown in the examples, after the fruit is treated by immersing in a solution of 100 mg / L GA3+5 g / L CaCl2, the single fruit weight of the kiwifruit can be significantly increased, the soluble solid content, ascorbic acid content, soluble sugar content and sugar-acid ratio of the fruit can be significantly improved, the acidity of the fruit can be significantly reduced, and the influence on the fruit peel thickness is not great. It can be seen that by using the accelerating agent, the comprehensive quality of the kiwifruit can be significantly improved on the premise of increasing the fruit yield.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of fruit tree cultivation, and relates to a use of a GA3-containing promoting agent in improving yield and quality of kiwifruit. BACKGROUND

[0002] Kiwifruit (Actinidia spp.) is a perennial deciduous liana, and the fruit is rich in a large number of mineral elements, natural pigments and phenolic substances and other antioxidant components, especially rich in vitamin C, and is known as the "King of Fruits". China is the country with the highest kiwifruit planting area and annual yield in the world. The annual yield of kiwifruit in China is about 2.38 million tons, accounting for 53% of the world's annual yield of kiwifruit. China is the origin and center of kiwifruit, and has rich resources of Actinidia plants. At present, the main Actinidia chinensis and Actinidia deliciosa are widely used for commercial cultivation. In addition, a small amount of Actinidia arguta (also known as kiwi) and Actinidia eriantha are also cultivated.

[0003] Kiwifruit fruits are generally small in natural growth state, and the yield is also low. In production, in order to improve the yield and quality of kiwifruit, researchers and growers have taken many measures, such as taking grafting, adjusting tree structure, applying different components of fertilizer and spraying swelling agent, etc. to strengthen tree vigor, improve photosynthetic capacity of tree, promote fruit growth and development, and then improve fruit yield and quality. Forchlorfenuron (CPPU) is the most commonly used plant growth regulator in kiwifruit production. CPPU belongs to phenylurea derivatives, can promote cell division, increase cell number and expand cell volume, has the effects of increasing single fruit weight and improving fruit setting rate, and has significant effect on increasing fruit size and improving yield, so it is widely used in kiwifruit production. However, improper use of CPPU can cause tree early decline, fruit quality reduction, and fruit shelf life shortening, etc. For example, excessive use of CPPU can cause fruit malformation, rough fruit skin, thick and large fruit core, even hollow fruit, rough fruit flesh, color change, flavor change, etc. Long-term use of CPPU can also cause imbalance between reproductive growth and vegetative growth, weaken tree stress resistance, easily cause 'large-small' year phenomenon, and even cause tree early decline and develop into small old tree. CPPU is a low-toxicity plant growth regulator, and large-dose use of CPPU can increase the residual amount of forchlorfenuron in kiwifruit and reduce the safety of products. The residual CPPU in kiwifruit may pose potential health risks to human body, such as trace residues of CPPU can harm the nervous system of human body and cause children's encephalitis and developmental disorders. Although the excellent yield-increasing effect of CPPU brings rich economic benefits to kiwifruit growers, in recent years, there are numerous negative reports about the use of swelling agent, consumers are more and more worried about the use of swelling agent and dare not to buy products using swelling agent, and the voice of banning swelling agent is getting stronger and stronger. Therefore, it is very urgent to select high-efficiency and non-toxic CPPU substitutes to promote the sustainable and healthy development of kiwifruit industry and protect people's health.

[0004] Gibberellin (GA3) is an important plant growth regulator, which plays an important role in the growth and development of plants. GA3 has important effects such as promoting plant growth, promoting flowering and fruiting, preventing fruit abscission, breaking dormancy, etc., and is widely used in agriculture, forestry and horticulture. For example, exogenous use of GA3 can promote the development of pear flower stalk and increase the size of pear fruit. In grape production, GA3 is the most commonly used growth regulator, and application after flowering can induce the increase of auxin in grape fruit body, promote the absorption of nutrients by young fruit, increase the seedless rate, lengthen the cluster, improve the fruit retention rate, and promote the fruit enlargement. GA3 is a plant hormone, and there is no corresponding binding receptor in human body, so a small amount of GA3 is harmless to human body. At present, there are few reports on the use of GA3 in kiwifruit, and the suitable application concentration and treatment combination of GA3 are not clear for the fruit quality and yield of kiwifruit. SUMMARY

[0005] The application provides the use of a GA3-containing promoting agent in improving the yield and quality of kiwifruit, which can significantly improve the comprehensive quality of kiwifruit while increasing the yield of fruit.

[0006] The application provides the use of GA3 in improving the yield and quality of kiwifruit, wherein the working concentration of the GA3 is 50-100 mg / L.

[0007] In one specific embodiment of the application, the working solution of the GA3 further comprises CaCl2.

[0008] In one specific embodiment of the application, the concentration of CaCl2 in the working solution is 5 g / L.

[0009] In one specific embodiment of the application, the quality comprises the contents of soluble sugar, ascorbic acid, soluble solids, sugar-acid ratio and fruit acid.

[0010] The application further provides a promoting agent for the yield and quality of kiwifruit, which comprises a mixed solution of GA3 and CaCl2.

[0011] The working concentration of GA3 in the mixed solution is 50-100 mg / L.

[0012] In one specific embodiment of the application, the working concentration of CaCl2 in the mixed solution is 5 g / L.

[0013] The application further provides a preparation method of the above-mentioned promoting agent, which comprises the following steps: dissolving CaCl2 in water to prepare a CaCl2 aqueous solution, dissolving GA3 in anhydrous ethanol to prepare a GA3 ethanol solution, mixing the CaCl2 aqueous solution and the GA3 ethanol solution, and then using distilled water to make up the volume to obtain the promoting agent.

[0014] In one specific embodiment of the application, 5 g of CaCl2 is completely dissolved in 100 mL of distilled water to prepare a 50 g / L CaCl2 aqueous solution; and 0.5-1 g of GA3 is completely dissolved in 100 mL of anhydrous ethanol to prepare a 5-10 g / L GA3 ethanol solution.

[0015] 10 mL of the GA3 ethanol solution is mixed with the CaCl2 aqueous solution, and then the volume is made up to 1 L to obtain the promoting agent.

[0016] The application further provides a method for improving the yield and quality of kiwifruit, which comprises fruit soaking with the above-mentioned promoting agent 15 days after the flowering of kiwifruit.

[0017] In one specific embodiment of the application, the fruit soaking time is 6-8 seconds.

[0018] Beneficial effects: the application provides application of GA3 in improving yield and quality of kiwifruit, wherein the working concentration of the GA3 is 50-100 mg / L. The application also provides a promoter containing GA3, wherein after the fruit is treated by the solution of 100 mg / L GA3+5 g / L CaCl2, the single fruit weight of the kiwifruit is significantly increased, the soluble solid content, ascorbic acid content, soluble sugar content and sugar-acid ratio of the fruit are significantly improved, the acidity of the fruit is significantly reduced, and the influence on the thickness of the kiwifruit peel is not great. Therefore, the promoter can significantly improve the comprehensive quality of the kiwifruit while increasing the yield of the fruit. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 Figure 4 is a result graph of the influence of different GA3 concentrations and treatment combinations on the thickness of the outer peel of kiwifruit, wherein T1-T7 represent treatment 1-treatment 6 and the control. DETAILED DESCRIPTION

[0020] The application provides application of GA3 in improving yield and quality of kiwifruit, wherein the working concentration of the GA3 is 50-100 mg / L.

[0021] The application does not have special limitations on the variety of the kiwifruit, and the conventional variety in the art can be used for operation, for example, the Chinese kiwifruit yellow-flesh variety 'Jin Feng' (also known as 'Feng Huang No. 1') is selected as the research material in the examples, and it is found that the GA3 and the promoter containing the GA3 can increase the single fruit weight of the kiwifruit and have little influence on the thickness of the peel of the kiwifruit; and can improve the quality of the kiwifruit, including the soluble sugar content, ascorbic acid content, soluble solid content, sugar-acid ratio and fruit acid content, for example, the soluble sugar content, ascorbic acid content, soluble solid content and sugar-acid ratio are improved, and the fruit acid content is reduced.

[0022] In one specific embodiment of the application, the working solution of the GA3 further comprises CaCl2, and the concentration of the CaCl2 in the working solution can be 5 g / L. Calcium is an important component of the cell wall and plays an important role in maintaining the integrity of the cell wall.

[0023] The application also provides a promoter for improving yield and quality of kiwifruit, which comprises a mixed solution of CA3 and CaCl2.

[0024] The working concentration of the GA3 in the mixed solution is 50-100 mg / L.

[0025] In one specific embodiment of the application, the working concentration of the CaCl2 in the mixed solution is 5 g / L, and the working concentration of the GA3 is 50-100 mg / L, for example, 100 mg / L GA3+5 g / L CaCl2.

[0026] The application also provides a preparation method of the above-mentioned accelerator, comprising the following steps: dissolving CaCl2 in water to prepare a CaCl2 aqueous solution, dissolving GA3 in anhydrous ethanol to prepare a GA3 ethanol solution, mixing the CaCl2 aqueous solution and the GA3 ethanol solution, and then using distilled water to make up the volume to obtain the accelerator.

[0027] In one specific embodiment of the application, 5g of CaCl2 is completely dissolved in 100mL of distilled water to prepare a 50g / L CaCl2 aqueous solution; 0.5-1g of GA3 is weighed and completely dissolved in 100mL of anhydrous ethanol to prepare a 5-10g / L GA3 ethanol solution.

[0028] 10mL of the GA3 ethanol solution is mixed with the CaCl2 aqueous solution, and then distilled water is used to make up the volume to 1L to obtain the accelerator.

[0029] The application also provides a method for improving the yield and quality of kiwifruit, comprising immersing the kiwifruit in the above-mentioned accelerator 15 days after the kiwifruit is in full bloom.

[0030] In one specific embodiment of the application, the immersing time is 6-8 seconds. When the fruit is immersed, the whole fruit surface should be ensured to be wet.

[0031] In order to further illustrate the application, the use of the accelerator containing GA3 provided by the application in improving the yield and quality of kiwifruit is described in detail below in combination with examples, but they should not be understood as limiting the protection scope of the application.

[0032] GA3 in the examples of the application 3、 NAA is dissolved in anhydrous ethanol, and CaCl2 is dissolved in water. When preparing, the concentrations are matched, for example, when preparing an accelerator containing 100mg / L of GA3 and 5g / L of CaCl2 (referred to as 100mg / L GA3+5g / L CaCl2), the specific preparation method is as follows: 5g of CaCl2 is completely dissolved in 100mL of distilled water; 1g of GA3 is completely dissolved in 100mL of anhydrous ethanol. 10mL of the dissolved solution of GA3 is mixed with the CaCl2 solution, and then distilled water is used to make up the volume to 1L.

[0033] Example 1

[0034] (I) Preparation of GA3 solutions with different concentrations and treatment combinations:

[0035] Treatment 1 (T1): 50mg / L GA3;

[0036] Treatment 2 (T2): 100mg / L GA3;

[0037] Treatment 3 (T3): 100 mg / L GA3 + 5 g / L CaCl2;

[0038] Treatment 4 (T4): 50 mg / L GA3 + 50 mg / L NAA;

[0039] Treatment 5 (T5): 5 g / L CaCl2;

[0040] Treatment 6 (T6): 50 mg / L NAA;

[0041] Control (T7): water.

[0042] (II) Fruit soaking treatment:

[0043] The Chinese kiwifruit yellow-fleshed variety 'Jin Feng' (also known as 'Feng Huang No. 1') was chosen as the research material. 'Jin Feng' was grafted onto a 6-year-old kiwifruit rootstock 'Jin Kui' and managed routinely. For each treatment combination, 3 trees with similar growth vigor were selected, and 50 young fruits were randomly selected from each tree for fruit soaking treatment 15 days after flowering. The fruits were soaked in the treatment solution for 6-8 seconds to ensure that the entire fruit surface was wet.

[0044] Control treatment: water was used to soak the fruits, and the treatment process was the same as (2).

[0045] (III) Fruit picking and treatment:

[0046] (1) After the fruits matured (soluble solids content ≥ 7.0%), fruits with uniform size, normal shape without deformity, and no diseases and pests were selected for picking. 30 fruits were picked from each tree. After the fruits were transported back to the laboratory and the field heat was removed, the external quality indicators of the fruits were detected, and the middle peel of the fruits was treated with liquid nitrogen and stored in a -80°C refrigerator for the determination of soluble sugar, titratable acid, ascorbic acid, and other fruit quality indicators.

[0047] (2) The soluble solids content of the fruits was measured using a handheld digital sugar meter (PAL-1). The soluble sugar content was determined using the anthrone colorimetric method. The total titratable acid content of the fruits was determined using the NaOH neutralization method. The ascorbic acid content was determined using the molybdenum blue colorimetric method. The dry matter content of the fruits was determined using the drying method, i.e., a 2mm thick peel slice was cut from the equatorial part of the kiwifruit and placed in a constant temperature drying oven at 60°C until it reached a constant weight. The dry matter content (%) was the ratio of the dry weight to the fresh weight. Each index had 3 biological replicates.

[0048] (3) Fruit appearance quality determination. Single fruit weight was measured using a one-thousandth electronic balance; the transverse and longitudinal diameters of the fruit were measured using a digital vernier caliper, and the fruit shape index (the ratio of the longitudinal diameter to the transverse diameter of the fruit) was calculated. There were 3 biological replicates, and 10 fruits were randomly selected for determination in each replicate.

[0049] (4) Fruit peel thickness determination. The peel of the equatorial part of the fruit was taken and cut into a rectangle with a length of 0.3-0.5 cm and a width of 0.3-0.5 cm, fixed with FAA (alcohol-acetic acid-formalin mixed fixing solution, prepared according to the proportion of 90 mL 70% ethanol + 5 mL glacial acetic acid + 5 mL formaldehyde), and dyed and observed using the safranin-fast green staining method. A Nikon upright white light microscope was used for observation and photography. Image-Pro Plus 6.0 software was used to measure the epidermal thickness on the axis perpendicular to the fruit surface.

[0050] (5) Data analysis. Microsoft Excel 2020 was used for data integration, and SPSS 22.0 was used for difference and correlation analysis.

[0051] (Four), test results:

[0052] (1) Effect of GA3 treatment on the external quality of kiwifruit

[0053] The effects of different GA3 concentrations and treatment combinations on the external quality of ‘Jin Feng’ kiwifruit are shown in Table 1. Compared with the control (CK), different GA3 concentrations and treatment combinations significantly promoted the growth of the transverse diameter, longitudinal diameter, and single fruit weight. Among them, the transverse diameter, longitudinal diameter, and single fruit weight of the fruit treated with 100 mg / L GA3 + 5 g / L CaCl2 were the largest, and there was no significant difference in fruit shape index between the treatment and the control.

[0054] Table 1 Effects of different GA3 concentrations and treatment combinations on the external quality of ‘Jin Feng’ kiwifruit

[0055] Treatment Transverse diameter (mm) Longitudinal diameter (mm) Fruit weight (g) Fruit shape index Treatment 1 51.42±1.78b 74.21±2.54a 111.28 ± 6.01 bc 1.45±0.06a Treatment 2 54.87±1.69a 73.19 ± 2.27 ab 111.92 ± 4.08 bc 1.34 ± 0.06 cd Treatment 3 54.16±2.95a 73.95±1.61a 116.18 ± 8.56 ab 1.37±0.08b Treatment 4 52.57 ± 1.89 ab 72.17 ± 2.95 bc 114.21 ± 7.38 abc 1.38±0.09b Treatment 5 52.43 ± 3.72 ab 67.49±5.73d 99.64±7.16d 1.29±0.12e Treatment 6 54.21±0.86a 72.23 ± 2.11 bc 121.23±4.21a 1.33 ± 0.04 cd Control 46.68±1.60c 63.19±2.46e 80.31±5.49e 1.36 ± 0.08 bc

[0056] Note: Different lowercase letters indicate significant differences (p<0.05).

[0057] (2) Effect of GA3 treatment on the internal quality of ‘Jin Feng’ kiwifruit

[0058] The effects of different GA3 concentrations and treatment combinations on the internal quality of 'Jinfeng' kiwifruit are shown in Table 2. In Table 2, soluble solids (%), dry matter (%), titratable acid (%), soluble sugar (%), and ascorbic acid (VC) (mg / 100g) are listed. Compared with the control (CK), different GA3 concentrations and treatment combinations had different effects on the internal quality of 'Jinfeng' kiwifruit. The 100mg / L GA3 + 5g / L CaCl2 treatment combination resulted in the highest soluble solids and dry matter content, but there was no significant difference compared to the CK. This treatment combination significantly reduced the titratable acid content, significantly increased the soluble sugar content, and significantly improved the sugar-acid ratio. Furthermore, this treatment combination had the highest ascorbic acid content among all treatments, significantly higher than other treatments and the control.

[0059] Table 2. Effects of different GA3 concentrations and treatment combinations on the intrinsic quality of 'Jinfeng' kiwifruit.

[0060] Treatment Total soluble solids Titratable acidity Soluble sugar Sugar-acid ratio VC Treatment 1 110.02 ± 0.10 bc 15.80±0.81b 18.58±0.47b 0.96±0.01d 12.85±0.73a 13.42±0.85a Treatment 2 14.90 ± 0.60 bc Treatment 3 18.43±0.83b 1.04±0.01b 10.71±0.31c 10.32±0.24d 113.13±0.21b 12.98 ± 0.35 ab 18.1±0.24a 19.79±0.50a 0.97±0.01d 12.54±0.28a Treatment 4 119.12±1.94a 15.10 ± 0.53 bc 12.10 ± 0.18 bc 17.74±0.48c 1.00±0.01c 12.11±0.05a 110.76 ± 1.47 bc Treatment 5 15.2 ± 0.70 bc Treatment 6 17.72±0.22c 1.01±0.01c 9.06±0.21d 9.01±0.17e 111.45±1.64b Control 14.6±0.94c 16.86±0.24d 1.04±0.01b 9.70±0.10d 9.34±0.15e 104.31+2.60d 1.08 ± 0.0 ba 17.9±0.68a 20.00±0.71a Figure 1 11.25±0.29b 10.42±0.22d 98.12±2.35e

[0061] (3) Effect of GA3 treatment on the thickness of the pericarp of 'Jinfeng' kiwifruit

[0062] The effects of different concentrations of GA3 and treatment combinations on the pericarp thickness of 'Jinfeng' kiwifruit are as follows: Fruit weight / g As shown in the figure. Compared with the control, the T1 and T3 treatments had no significant effect on the thickness of the pericarp of 'Jinfeng' kiwifruit, while the T2, T4 and T6 treatments significantly increased the pericarp thickness, and the T5 treatment decreased the pericarp thickness.

[0063] In conclusion, soaking the fruit in a solution of 100 mg / L GA3 + 5 g / L CaCl2 significantly improves the overall quality of kiwifruit. This treatment combination significantly increases the weight of individual kiwifruit, significantly increases the content of soluble solids, ascorbic acid, and soluble sugar, as well as the sugar-acid ratio, and significantly reduces the acidity of the fruit, but has little effect on the thickness of the kiwifruit peel.

[0064] Comparative Example 1

[0065] The CPPU treatment described in the paper "Effects of Chlorpyrifos (CPPU) Fruit Soaking on the Quality of 'Fenghuang No. 1' Kiwifruit" published in *South China Fruits* was used as a comparative example. The results showed that CPPU treatment of 'Fenghuang No. 1' kiwifruit generally resulted in increased single-fruit weight, decreased fruit shape index, increased sugar-acid ratio, and increased dry matter and soluble solids content. The optimal treatment concentration was 2.5 ml / L (Tables 3 and 4).

[0066] Table 3. Appearance quality of 'Fenghuang No. 1' kiwifruit treated with different concentrations of CPPU

[0067] Concentration / mL·L -1 ]] Longitudinal diameter / mm Transverse diameter / mm Fruit shape index Lateral diameter / mm CK (water) 1.37 ± 0.03 cd 97.89±1.89e 71.28±1.76e 49.89±0.58e 1.42±0.03a 45.35±1.24d 1.0 113.42±7.18d 74.62±0.88c 53.35±1.92d 1.39 ± 0.02 abc 47.94±2.03b 2.5 141.31±6.97a 79.64±1.78a 56.19±0.35b 72.82 ± 1.37 de 50.12±1.37a 4.0 128.43±2.64b 54.44 ± 2.51 cd 1.41 ± 0.05 ab 121.65 ± 7.16 bc 48.10±1.16b 5.5 55.10 ± 0.56 bc 76.83±1.18b 1.38 ± 0.01 bcd 46.61 ± 1.72 bcd 115.29 ± 5.84 cd 7.0 55.22 ± 0.91 bc 77.06±1.39b 47.13 ± 0.71 bc 1.35±0.04d 73.59 ± 1.69 cd 8.5 108.69±7.16d 46.09 ± 1.31 cd 58.39±1.69a 1.29±0.05e 1.38 ± 0.01 bc 10.0 101.28±6.08e 71.58±1.34e 51.15±1.04e ​ 45.18±0.67d

[0068] Note: Fruit soaking was carried out 15 days after full bloom, the concentration was calculated according to 0.1% forabenzuron soluble liquid, and different lowercase letters represented significant difference (p<0.05).

[0069] Table 4 Intrinsic quality of 'Fenghuang No.1' kiwifruit treated by different concentrations of CPPU

[0070]

[0071] Note: Fruit soaking was carried out 15 days after full bloom, the concentration was calculated according to 0.1% forabenzuron soluble liquid, and different lowercase letters represented significant difference (p<0.05).

[0072] From the above, it can be seen that the fruit quality index of the fruit treated by using 100mg / L GA3+5g / L CaCl2 solution is similar to the result of 2.5ml / L CPPU treatment, but the intrinsic quality indexes such as soluble solids, dry matter, titratable acid, soluble sugar, sugar acid ratio, ascorbic acid and the like are higher than those of CPPU treatment. The results show that the fruit treated by using 100mg / L GA3+5g / L CaCl2 solution can achieve similar effect to CPPU treatment, and some intrinsic indexes are better than those of CPPU treatment, so it is an effective alternative to CPPU treatment.

[0073] Although the above embodiment has made a detailed description of the present application, it is only a part of the embodiments of the present application, but not all the embodiments, and people can also obtain other embodiments according to the present embodiment without creativity, and these embodiments all belong to the protection scope of the present application.

Claims

1. Use of a stimulator to increase the yield and quality of kiwifruit, characterized in that, The accelerator is a mixed solution of GA3 and CaCl2; The working concentration of GA3 in the mixed solution is 50-100 mg / L, and the working concentration of CaCl2 in the mixed solution is 5 g / L. The quality includes soluble sugar, ascorbic acid content, soluble solid content, sugar-acid ratio and fruit acid content.

2. A method of improving yield and quality of kiwifruit, characterized by, The fruit is soaked with the accelerator 15 days after the kiwi flowers bloom; the accelerator is a mixed solution of GA3 and CaCl2; The working concentration of GA3 in the mixed solution is 50-100 mg / L, and the working concentration of CaCl2 in the mixed solution is 5 g / L.

3. The method of claim 2, wherein, The fruit soaking time is 6-8 seconds.

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