CN111201936A

CN111201936A - Selenium-rich kiwi fruit and cultivation method thereof

Info

Publication number: CN111201936A
Application number: CN201911302150.7A
Authority: CN
Inventors: 程水源; 饶申; 许锋; 黄仁华; 李丽
Original assignee: Wuhan Polytechnic University
Current assignee: Wuhan Polytechnic University
Priority date: 2019-12-17
Filing date: 2019-12-17
Publication date: 2020-05-29

Abstract

The invention belongs to the technical field of biochemistry, and particularly discloses selenium-rich kiwi fruits and a cultivation method thereof. The cultivation method comprises the following steps: spraying selenite solution on kiwi fruit leaves during the flowering period of kiwi fruit, and obtaining the selenium-rich kiwi fruit after the kiwi fruit is mature physiologically; wherein the concentration of selenium in the selenite solution is 25 mg/L-100 mg/L. Compared with the traditional method for applying selenium to soil, the method overcomes the defects of complex operation, low utilization rate and easy soil pollution, and provides a simple selenium-rich cultivation method for the kiwi fruits.

Description

Selenium-rich kiwi fruit and cultivation method thereof

Technical Field

The invention belongs to the technical field of biochemistry, and particularly relates to a selenium-rich kiwi fruit and a cultivation method thereof.

Background

Kiwi fruit is a fruit king recognized in the world, has extremely high nutritional value and medical health care effect, and is one of novel health care fruits which are competitively developed in all countries in the world, particularly developed countries, and optimal fruits recommended by the world health organization. The kiwi fruits are native to China and are widely cultivated in China, and the kiwi fruits are fresh and tender in quality, rich in nutrition and delicious in flavor. In recent years, kiwi fruits are popular with consumers as special fruits, the cultivation area in China is rapidly enlarged, the planting area reaches about 100 ten thousand mu, and the total area of kiwi fruits accounts for about 50% of the total area of kiwi fruits cultivated in the world.

The kiwi fruit has rich nutritive value, contains rich trace elements such as calcium, potassium, selenium, zinc, germanium, etc., 17 amino acids essential to human body, and rich vitamins such as vitamin C, gluconic acid, fructose, citric acid, malic acid, actinidine, proteolytic enzyme, tannin pectin and saccharides. Selenium is one of essential trace elements in human life, is an antioxidant in human body, and has the functions of improving human immunity, eliminating excessive oxygen free radicals in human body, preventing and resisting cancer, reducing blood fat and blood pressure, preventing liver virus diseases and other biological functions. Selenium is taken in by a human body mainly through a dietary way, and kiwi fruits which are popular and widely cultivated by people can be used as an effective carrier of selenium to supplement the requirements of the human body. Therefore, the cultivation of the selenium-rich kiwi fruits through cultivation measures has important significance for improving the nutritional value of the kiwi fruits and increasing the selenium intake of people. The traditional method for adding selenium in soil is used in selenium-rich cultivation, the method has low conversion rate and complex operation, and is easy to generate selenium residue in soil to cause soil selenium pollution, thus being not beneficial to large-scale industrialized planting.

Disclosure of Invention

The invention aims to provide the selenium-rich kiwi fruit and the cultivation method thereof, and the cultivation method is simple to operate, high in selenium conversion rate, environment-friendly and suitable for large-scale industrial planting.

In order to achieve the above object, the present invention provides a cultivation method of selenium-rich kiwi fruit, including:

in the flowering period of the kiwi fruits, selenite solution with the selenium concentration of 25 mg/L-100 mg/L is sprayed on kiwi fruit leaves, and the selenium-rich kiwi fruits are obtained after the kiwi fruits reach physiological maturity.

According to the invention, the concentration of selenium in the selenite solution is preferably 45-55 mg/L.

The selenite adopted in the invention is soluble selenite, the solution of the selenite is prepared by mixing the soluble selenite with water, and preferably, the selenite is sodium selenite.

In the cultivation method provided by the invention, no special requirement is imposed on the time for spraying, and the spraying is only carried out in the flowering period of the kiwi fruits. In order to enable inorganic selenium to be absorbed and converted into organic selenium to the maximum extent in the kiwi fruits and enable the kiwi fruits not to generate selenium poisoning, preferably, the spraying frequency is 2-5 times. In order to further increase the absorption and conversion efficiency, the spraying interval is 1-3 days.

On the other hand, the invention provides the selenium-rich kiwi fruit cultivated by the cultivation method.

In the kiwi fruit cultivated by the method, preferably, the selenium content in the pulp of the kiwi fruit is 75-130 mug/kg, the protein selenium content is 25-38 mug/kg, and the organic selenium content is 50-80 mug/kg.

Compared with the traditional method for applying selenium to soil, the method overcomes the defects of complex operation, low utilization rate and easy soil pollution, and provides a simple selenium-rich cultivation method for the kiwi fruits.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The above and other objects, features and advantages of the present invention will become more apparent by describing in more detail exemplary embodiments thereof with reference to the attached drawings, in which like reference numerals generally represent like parts throughout.

Fig. 1 shows a schematic diagram of iron ion reduction/oxidation resistance of selenium-enriched kiwi fruits in the examples and comparative examples of the present invention.

Fig. 2 shows a schematic diagram of the oxidative radical absorption capacity of selenium-enriched kiwi fruit samples in the examples and comparative examples of the present invention.

Detailed Description

Preferred embodiments of the present invention will be described in more detail below. While the following describes preferred embodiments of the present invention, it should be understood that the present invention may be embodied in various forms and should not be limited by the embodiments set forth herein.

Example 1

Spraying sodium selenite solution with selenium concentration of 25mg/L onto kiwi fruit leaves in flowering period of kiwi fruit, spraying once every two days for three times, and obtaining selenium-rich kiwi fruit when kiwi fruit reaches physiological maturity.

Example 2

Spraying sodium selenite solution with selenium concentration of 50mg/L onto kiwi fruit leaves in flowering period of kiwi fruit, spraying once every two days for three times, and obtaining selenium-rich kiwi fruit when kiwi fruit reaches physiological maturity.

Example 3

Spraying sodium selenite solution with selenium concentration of 100mg/L onto kiwi fruit leaves in flowering period of kiwi fruit, spraying once every two days for three times, and obtaining selenium-rich kiwi fruit when kiwi fruit reaches physiological maturity.

Comparative example 1

And (3) spraying distilled water on the kiwi fruit leaves once every two days and three times in total in the flowering period of the kiwi fruit, and obtaining the selenium-enriched kiwi fruit after the kiwi fruit reaches physiological maturity.

Comparative example 2

Spraying sodium selenite solution with the selenium concentration of 10mg/L onto kiwi fruit leaves in the flowering period of kiwi fruit, wherein the sodium selenite solution is sprayed once every two days for three times, and selenium-enriched kiwi fruit is obtained when the kiwi fruit reaches physiological maturity.

Comparative example 3

Spraying sodium selenite solution with the selenium concentration of 110mg/L onto kiwi fruit leaves as raw materials at the flowering period of kiwi fruit, spraying once every two days for three times, and obtaining the kiwi fruit after the kiwi fruit reaches physiological maturity.

The kiwi fruits obtained in examples 1-3 and comparative examples 1-3 were subjected to selenium content measurement, and the results are shown in table 1 below:

TABLE 1

As can be seen from table 1, spraying sodium selenite solution to the leaf surface can effectively increase the selenium content in the kiwi fruits, and the total selenium and organic selenium content in the pulp increases with the increase of the selenium concentration. When the selenium spraying concentration is 100mg/L, the total selenium content in the pulp reaches 124 mug/kg, the organic selenium content reaches 76.28 mug/kg and accounts for 61.43 percent of the total selenium, the protein selenium content is 36.64 mug/kg and accounts for 48.04 percent of the organic selenium, and the polysaccharide selenium content is 17.71 mug/kg and accounts for 23.22 percent of the organic selenium.

When the selenium spraying concentration is less than 25mg/L, the selenium content in the kiwi fruits can not reach the selenium-rich standard; when the selenium spraying concentration is more than 100mg/L, the yield of the kiwi fruits is reduced, the fruit drop is obvious, black spots appear on the surfaces of the kiwi fruits, partial kiwi fruits are even malformed, the quality of the kiwi fruits is poor, and the commercial value is not high.

During the flowering period of the kiwi fruits, 100mg/L sodium selenite solution is sprayed on leaves, the kiwi fruits are most enriched in selenium, the organic selenium content is high, and selenium poisoning is avoided; the effect of the kiwi fruits obtained by spraying 50mg/L sodium selenite solution on the leaves is similar to that of 100mg/L sodium selenite, and the spraying effect of the 50mg/L sodium selenite solution is the best in consideration of cost saving and environmental protection.

Meanwhile, the kiwi fruits of examples 1 to 3 and comparative examples 1 to 3 were measured for iron ion reduction/oxidation resistance (FRAP) and Oxidative Radical Absorption Capacity (ORAC), also called oxidation resistance, respectively, and the measurement results are shown in fig. 1 to 2.

From FIGS. 1-2, it can be seen that the iron ion reducing/antioxidant capacity and the oxidative radical absorption capacity of the pericarp, pulp and seed all increased with increasing selenium treatment concentration.

The change of the selenium content and the antioxidant capacity shows that the sodium selenite sprayed on the leaves can obviously improve the total selenium content and the organic selenium content of the kiwi fruit pulp, improve the antioxidant capacity of the kiwi fruit and greatly improve the quality of the kiwi fruit.

Having described embodiments of the present invention, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A cultivation method of selenium-rich kiwi fruits is characterized by comprising the following steps:

and spraying selenite solution with the selenium concentration of 25-100 mg/L to kiwi fruit leaves during the flowering period of kiwi fruit, and obtaining the selenium-rich kiwi fruit after the kiwi fruit reaches physiological maturity.

2. The cultivation method as claimed in claim 1, wherein the concentration of selenium in the selenite solution is 45-55 mg/L.

3. A cultivation process as claimed in claim 1, wherein the selenite is sodium selenite.

4. The cultivation method according to claim 1, wherein the number of spraying is 2 to 4.

5. The cultivation method according to claim 4, wherein each spraying is performed at an interval of 1 to 3 days.

6. Selenium-enriched kiwi fruit cultured by the cultivation method according to any one of claims 1 to 5.

7. The selenium-enriched kiwi fruit of claim 6, wherein the selenium content in the pulp of the selenium-enriched kiwi fruit is 75-130 μ g/kg.

8. The selenium-enriched kiwi fruit of claim 6, wherein the pulp of the selenium-enriched kiwi fruit contains 50-80 μ g/kg of organic selenium.

9. The selenium-enriched kiwi fruit of claim 6, wherein the selenium protein content in the pulp of selenium-enriched kiwi fruit is 25-38 μ g/kg.