Abstract According to the understanding of current situation of Guangxi selenium containing passion fruit products and the advantages and disadvantages of related product markets， the corresponding improvement plans were proposed for the supply and demand of products and the adjustment of industrial development， so as to provide theoretical data support for optimizing the industrial structure and increasing the market share of selenium rich passion fruit in Guangxi.
　　Key words Se enrichment; Passion fruit; Current situation; Development strategy
　　 Passion fruit （Passiflora edulia Sims）， also known as Jidanguo， is a kind of edible plant fruit with good nutritional value. Passion fruit has the effect of protecting gastrointestinal tract， contains super fiber which can act on the gastrointestinal tract and has the effects of regulating the environment inside the gastrointestinal tract and eliminating impurities and poisons of the gastrointestinal tract. Meanwhile， it has a good effect of promoting digestion and absorption of the gastrointestinal tract， thereby protecting the health of the gastrointestinal tract. Selenium rich passion fruit is rich in selenium， which is a very important element in organisms. The lack of selenium in human body can lead to a series of problems in the body. Selenium has strong binding ability with heavy metals， especially with cadmium， forming metal selenoproteins， which effectively prevent damage to the kidneys and central nervous system by heavy metals and protect the healthy and normal operation of the body. Meanwhile， selenium also has the function of enhancing the immune system. After entering the body， selenium can be used as a foreign matter to stimulate the bodys immune system and enhance the bodys immune function. Selenium enriched passion fruit combines the functions of selenium and passion fruit to enhance human immunity and promote human metabolism， so as to improve blood circulation efficiency， speed up blood vessel renewal， facilitate the absorption and utilization of nutrients and promote blood circulation.
　　According to the latest data， the per capita selenium intake of Chinese nationals is 14-21 μg/d， while the normal daily demand for a body is 60-250 μg/d. After the reform and opening up， China vigorously develops the economy， and up to now， Chinas living standards have changed dramatically. People are no longer worried about simple food and clothing problems， but think about how to eat better and healthier. After the Internet is developed， peoples vision becomes wider， and they gradually know what foods are good for health， so selenium enriched foods are being sought after by more and more people， and the market still has great development needs. 　　Current Status and Favorable Conditions for Planting Selenium enriched Passion Fruit
　　Planting status of selenium enriched passion fruit
　　The selenium enriched passion fruit in Guangxi is mainly concentrated in the southeastern part of Guangxi， and the development in Guigang City and Beiliu City is the most prominent. Guigang City of Guangxi Province， the largest region rich in passion fruit， is located in the lower subtropical China and the mid subtropical zone of China， which has a superior geographical position， enough sunshine， comfortable temperature and abundant rain. It is very suitable for the growth of passion fruit. Most importantly， the land is rich in selenium， and up to one third of the land has a higher selenium content. The local people achieve a high utilization value of the land， and produce a variety of selenium enriched agricultural products. By August 2018， the planting area of passion fruit in Guigang City has exceeded 7 000 hm2， and the annual production of passion fruit has reached 100 000 t. According to the data of Ali in January 2018， the production and sales of passion fruit in Beiliu City of Guangxi Province has been far ahead in the country， accounting for 76%. In recent years， with the support of the national policy， a large number of young people started their business， and the industrial chain of passion fruit has been continuously repaired and perfected， gradually forming a sound passion fruit industry system that integrates the production， processing and sales of passion fruit. The data show that there are four passion fruit production and processing enterprises in Beiliu City， which are responsible for the production of related products such as passion fruit juice， with an annual production capacity of 20 000 t. Moreover， the processing enterprises have rich production types， more than ten kinds. The transportation of products is also relatively developed， and the courier services companies are widely distributed， 54 companies in total， which also do a good job in product preservation， involving six companies.
　　Selenium enriched passion fruit has obvious economic benefits
　　More than half of Chinas population， which is a large population， lives in mountainous areas. The geographical environment in which residents live depends on the job nature of residents. Nowadays， the issue of agriculture， rural areas and farmers is also a major problem that China urgently needs to solve. As people have gradually realized the value of passion fruit in recent years， the market of passion fruit is optimistic， and the fruit can be harvested in the very year of planting. Therefore， passion fruit is promoted by many places as a "short and fast" precision poverty alleviation project. Compared with other industries， the technical requirements for selenium enriched agricultural products are not high， so there is no need for a large amount of capital investment in the cultivation and processing of selenium enriched agricultural products， which contributes to the large scale cultivation of agricultural products. Selenium enriched agricultural products are widely accepted by consumers in the market， and consumers have higher recognition of the nutritional value of such agricultural products， resulting in higher market demand for selenium enriched agricultural products. Moreover， the profits of such agricultural products are higher than the profits of other agricultural products， and analyzing such products in the long term， the market prospects for such agricultural products are good. 　　Guangxi has abundant selenium containing land resources
　　The selenium enriched soil in Guangxi has a large area in a wide distribution with a high average value of selenium in the soil. It is the largest area in Chinas multi target selenium rich areas. According to data of 2016 from the Guangxi Bureau of Geological and Mineral Resources， Guangxis contiguous selenium rich soil area is of 30 000 km2， ranking first in the country， and the arable area is 6 626 km2， ranking first in the country. And the selenium content of soil is also higher than any area in the country. According to the data of the Ministry of Agriculture， among the 2 182 soil samples from 286 villages and towns in 34 counties （cities， districts）， 1245 samples （with a selenium content greater than 0.40 mg/kg） reached the selenium rich soil standard， accounting for 57.1%; and the average content of selenium in the soil was 0.55 mg/kg， which is twice the national average （0.26 mg/kg） and is among the best in the country.
　　Guangxi is blessed with climatic conditions for growing passion fruit
　　Passion fruit is a thermophilic plant. Temperature and ground temperature play a major role in its growth and development. Passion fruit is planted in areas where the annual average temperature is above 18 ℃ and the winter temperature is not lower than 0 ℃， and the plant will be seriously damaged or even die at -2 ℃. Guangxi is a tropical monsoon climate and subtropical monsoon climate region， where the annual sunshine hours are 2 300-2 800 h and the annual rainfall is between 1 500-2 000 ml. The growth and development of plants requires sufficient sunlight and moisture， as well as suitable external conditions， and passion fruit is no exception. A good planting environment is conducive to the growth of passion fruit， so the yield is higher. The geographical location of Guangxi provides a unique growth resource for passion fruit.
　　Existing Problems
　　The standardized quantitative selenium enriching technology is not mature enough
　　Compared with grape， mulberry， kiwi， etc.， passion fruit has a weaker absorption of selenium. For example， in a test field in Guigang， under the action of the selenium enhancer （300）， the selenium content of the passion fruit is only 0.002 6 mg/kg， while the contents in dragon fruit and rice are 0.30 and 0.28 mg/kg， respectively; under the action of selenium enhancer （500）， the selenium content of passion fruit was only 0.002 8 mg/kg， while the contents of pitaya and rice are 0.41 and 0.32 mg/kg， respectively; and in the case of selenium enhancer （800）， the selenium content of passion fruit is only 0.003 8 mg/kg， while the contents of pitaya and rice are  0.56  and  0.40  mg/kg， respectively. Research institutes and enterprises should improve the selenium enriching technology of passion fruit according to the different regions and the growth habits of different crops， to promote growth and improve the yield and disease resistance of passion fruit. In some areas， there is excessive dependence on the foreign selenium， and the unique soil conditions are not fully used， so inorganic selenium can be converted into organic selenium to improve the activation of selenium. 　　The disease prevention and control has not been broken through， and the cultivation management is difficult
　　Passion fruit is planted in the same way as ordinary plants. Its growth is hindered due to environmental influences， especially soil borne rot disease， which occurs within one or two years after planting， especially in high temperature and when it rains for many days， causing great damage to plants. In response to such diseases， China has not yet developed corresponding seedlings resistant to root rot， which is a major factor affecting the yield of passion fruit. Severe pests and diseases are also one of the important problems. When weeds are not cleaned up in time， a considerable part of the pests and diseases are spread from the surrounding trees. There are also many problems in the production management of passion fruit. The first is the interference of pests and diseases， because weeds are inconvenient to handle and cause many harmful pests and diseases， affecting the normal growth of passion fruit. Secondly， the production technology is immature. Because the ripening time of passion fruit is not unified， the picking of passion fruit has become particularly difficult. The existing solution is to pick every 3 d， but this solution leads to longer work time， larger workload and lower work efficiency. Therefore， it is necessary to improve the production technology continuously.
　　The economic and technological investment is large， and the development is limited
　　Based on the understanding of the current situation， the initial cost of planting passion fruit mainly includes three aspects. ① The early construction of the reinforced cement columns and iron lines will cost about 1 200 yuan， and after the completion of the project， it is also necessary to avoid the collapse of the greenhouse caused by external factors. ② The capital requirement for formal planting is 800 to 1 200 yuan. And ③ It is difficult to avoid risk. Because of the funding problem， the planting site is often unsatisfactory. Because the rainy season in Guangxi is certainly to be rainy， if there is a problem with the site selection， the rainwater will not be discharged， and the passion fruit seedlings will die due to excessive rain. Also， in the case of no rain and dry weather for many days， the plant will be dehydrated， and the growth and development of the individual will be deteriorated， so that the yield is reduced. Due to the lack of effective prevention and handling of abnormal weather， farmers often feel overwhelmed when abnormal weather occurs， and some are almost completely annihilated and suffer heavy losses. 　　There are certain requirements for the cultivation of passion fruit. For farmers who have insufficient theoretical knowledge， the planting process does encounter some difficulties. And the selenium enriched agricultural products have relatively high requirements on the soil. Therefore， in the specific planting process， the farmers need to strictly control the plants through strict temperature control， humidity control and supplement of nutrients required by crops in different periods， otherwise it will lead to poor growth of crops and greatly reduced yield. Moreover， because of the characteristics of passion fruit， i.e.， belonging to the climbing plant， it can grow normally by relying on corresponding supports， and some farmers build the supports at will， which are not high enough for the plant to grow well. Neglecting the details of the daily growth management of crops， the situation of weed cleaning and random pruning of branches will directly affect the yield.
　　The tertiary industrialization is not well conducted
　　The Beilius passion fruit industry has developed well. In recent years， it has formed multiple mutually beneficial intensive industrial systems：  "e commerce +production base+farmer"，  "processing  enterprise+e commerce+base+farmer"， "e commerce+logistics company+base+farmer" and  "cooperative+ e commerce +farmer"， forming a competitive new industrial structure from product planting， technology update and iteration for increasing production， multi channel promotion and sales， to the establishment of brand effect and the improvement of industrial system. In other regions， the development of passion fruit， under the basic conditions including the slow pace of development， the lack of innovation， the imperfect industrial structure and the single product， drastic development and reform is also required to combine the cultivation and processing of agricultural products， catering and even tourism， so as to create an industrial system that one plus one is greater than two.
　　Agricultural Biotechnology2019
　　Development Strategy of Selenium rich Passion Fruit Industry
　　Introducing advanced technology， strengthening the capacity of scientific research
　　At present， the selenium rich passion fruit in Guangxi is mainly based on fresh fruit， and there are not many deep processed products， which greatly reduces the profit of selenium rich passion fruit， and is also not conducive to the promotion of selenium rich passion fruit. In recent years， China has supported the vigorous development of agriculture， and has given certain preferential policies. It has opened up a shortcut in the production of selenium enriched agricultural products. The quality of agricultural products has been effectively improved through the support of planting management technology for selenium enriched agricultural products， and the yield has also been greatly improved. Through the multi angle innovation of selenium enriched agricultural products， the product category has been increased， which has increased consumers choice of selenium enriched agricultural products. It is necessary to make full use of the selenium enriched passion fruit series， expand the scale of selenium enriched passion fruit planting process and innovation in planting areas and rationally use the accessory products of passion fruit and process green fruits， roots and leaves， so as to reduce production waste and increase profits. At the same time， we will improve the production and sales process of passion fruit， create green and non added foods with standardized production and sales system， and create only the local passion fruit brand. At the same time， we should improve the production and sales process of passion fruit， create green and non added foods with standardized production and sales system， and create only the local passion fruit brand. Moreover， varieties with high selenium content free of pests and diseases can be bred by the aid of domestic plantation related research institutes or institutions through the improvement of the growth conditions of crops and technological innovation. Finally， the nutrient supply of selenium enriched agricultural products can be improved to grow high yield crops with limited fertilizers. 　　Rational planning of planting， full control of pests and diseases
　　The plantation site should be strictly controlled. The address is selected according to the properties of the passion fruit and the local natural conditions. The data show that the altitude of 1 100 m is a planting limit of passion fruit. The land with an altitude  above  1 100 m is not suitable for the cultivation of passion fruit. The external environments of different areas are also slightly different. In some areas， the climate is not suitable for planting， and passion fruit should be strictly eliminated. Planting should be carried out in the areas within the companys planning， and reasonable arrangements should be made in light of the local labor force. We will continue to vigorously build a demonstration base for selenium rich passion fruit planting with outstanding characteristics and obvious agglomeration effect， so as to build a leading enterprise which can ensure every success in each plan.
　　Government policy support
　　In 2017， China proposed new policies to support agricultural development in various regions. The "Notice on Doing a Good Job in the Application for the National Agricultural Comprehensive Development and Industrialization Development Project in 2017" mentioned： for the construction of agricultural planting bases and agricultural product processing and agricultural product circulation facilities， priority can be given to the construction of bases and introduction and promotion of new technologies and new varieties. Judging from the work done by China in 2017， Chinas support for the development of agriculture is still very large. In view of the current planting situation in Guangxi， the selenium enriched agricultural product industry in Guangxi is relatively simple， with relatively scattered planting distribution and low output， and the farmers planting confidence is insufficient. As China vigorously supports the cultivation of agricultural products， we can enhance the propaganda of policies to increase farmers interest in planting agricultural products， and systemize， standardize and specialize crop planting to improve the quality and output of passion fruit and increase farmers income. Moreover， with the development of agriculture， the requirements of technology are getting higher and higher. We also need to continuously optimize the industrial structure and develop the "two high and one excellent" pollution free crops. Nowadays， farmers are led by party committees and governments at all levels， and the planting level and industrial development will definitely get better. 　　Integration and development of primary， secondary and tertiary industries
　　For the development of selenium enriched agricultural products， on the one hand， to improve the yield and quality of selenium enriched agricultural products， it is necessary to control the cultivation of agricultural products， to control the specific site selection and subsequent conditions， and to optimize the matching of pesticides and fertilizers， so as to improve the output and quality of agricultural products. On the other hand， it is necessary to improve the industrial system of selenium enriched agricultural  products  and to expand the industrial system of agricultural products， which means to process agricultural products and create a variety of products， and the sales channels of agricultural products can be dimensionalized to enrich the sales area of agricultural products. Furthermore， industrial integration can be strengthened to make full use of local resources. The industry of selenium rich passion fruit can be combined with tourism industry and cultural industry， to mutually promote economic development among multiple industries.
　　Selenium rich passion fruit belongs to the sunrise industry in Guangxi Province. A multi category product line that is satisfactory to the public can be created by rationally planning the industrial development， optimizing the industrial structure and analyzing the market demand， thereby creating a new form of industry through multi industry convergence.
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