Supported by Shanxi Key Project of Coal Based Science and Technology (FT2014-03); Doctorate Research Foundation of Shanxi Academy of Agricultural Sciences (YBSJJ1616); Construction of Shanxi Science and Technology Basic Conditions Platform (201705D121012).

1 Introduction

Mycorrhiza is a symbiotic association between a fungus and the roots of a vascular host plant. The term mycorrhiza refers to the role of the fungi in the plants’ rhizosphere, its root system. Mycorrhizae play important roles in soil biology and soil chemistry. Mycorrhiza plays an important role in soil structure, plant nutrient absorption and growth, biodiversity and the productivity of agriculture and natural ecosystems. According to the different morphological structure, mycorrhizae can be divided into six types. (i) Arbuscular mycorrhiza (AM), (ii) Arbutoid mycorrhiza, (iii) Ectomycorrhiza (EM), (iv) Ericoid, (v) Monotropoid mycorrhiza (MM), and (vi) Orchid mycorrhiza (OM). In these types, arbuscular mycorrhiza and ectomycorrhiza are common and have the highest economic value, and are symbiotic with cereal crops, vegetable, and fruit, and trees and shrubs[1-2].

Edible mycorrhizal fungi (EMF) are the collective name of large ectomycorrhiza with edible and medicinal values. They have to establish symbiotic relationship with plant roots, then form edible (including medicinal) fungi with sporocarp. Due to medicinal effect, they are also called edible and medicinal mycorrhizal fungus. Mycorrhizal fungus resources are very rich. In more than 2 200 kinds of edible fungi in the world, edible mycorrhizal fungi account for about 1/3. After systematically survey on the names of edible fungi in China, Dai Yucheng etal.[3] systematically collected 966 classes, including 936 species, 23 varieties, 3 subspecies, and 4 variants. In these, 677 species are edible mycorrhizal fungi, accounting for 70% of total edible fungi in China.

由表5可知，安徽省区域旅游发展水平差异明显．黄山市与池州市旅游区位熵得分较高，旅游产业发展水平在省内处于领先地位．黄山市、池州市、安庆市、宣城市、合肥市、芜湖市、六安市旅游区位熵均大于0.74，旅游业发展状况较好，可划分为旅游发展的优势区域;其他城市均小于0.74，旅游业发展状况一般，可划分为一般旅游区域．

本研究选择采用焦虑自评量表(SAS)和抑郁自评量表(SDS)评价本,研究两组患者的心理状况,两种评分均以50分作为基准线,分数越高表示患者的焦虑和抑郁状况越严重。对于两组患者的满意度情况进行调查,选择自制量表评分进行评价,评分满分为100分,分数越高,表示患者满意度越高。

The key technology for artificial cultivation of edible mycorrhizal fungi is to synthesize the mycorrhizal symbiotic seedlings and to produce the mycorrhizal symbiotic seedlings in large quantities. At present, some edible mycorrhizal fungi such as T. matsutake, T. indicum, and B. edulis Bull., but it is still not be able to realize mass production, most types of edible mycorrhizal fungi still can not produce mycorrhizal symbiotic seedlings smoothly. Therefore, the production of mycorrhizal synthetic seedlings is still the key technique for domestication of cultivated mycorrhizal fungi, and it also needs a lot more effective technology development.

Wutai Mountain is one of place of origins of the Buddhism. The natural vegetation is dominated by grass and consists of meadow grasslands and thickets. The wildlife resources are abundant. Wutai Mountain mushroom is a group of edible and medicinal resources naturally grown in Wutai Mountain. It has rich nutrient, delicious taste, and health care functions. And many types are edible mycorrhizal fungi, such as Lepistanuda (Bull.: Fr.) Cooke and Tricholomagambosum (Fr.) Gill. There are 11 kinds of main mushrooms in Wutai Mountain. The famous mushrooms are silver plate and Lentinulaedodes (Berk.) Pegler. They belong to edible mycorrhizal fungus and are rich in nutrients such as protein, sugar, fat, vitamin and mineral elements, especially higher protein content than other edible fungi, and they also produce clitocybin, have anti-tuberculosis effect, and high development value.

2 Research status of edible mycorrhizal fungi

2.2 Ecological researches about edible mycorrhizal fungi The researches about biological characteristics of mycorrhizal fungi, as well as the relationship with non-biological factors and environmental factors, are concentrated on the distribution of edible mycorrhizal fungi, their growth and development, physiological metabolism and their functions. According to studies of He Xinhua etal.[1] and Tang Chao etal.[2], it is generally believed that there is a general symbiotic relationship between edible mycorrhizal fungi and tree roots, but some mycorrhizal mushrooms are symbiotic with shrubs or herbs[6], such as Tricholomamongolicum Imai distributed in Zhangjiakou and Inner Mongolia and many kinds of edible mycorrhizal edible fungi in the eastern foot of the Himalayas[7]. The formation and development of edible mycorrhizal fungi are the result of information exchange between mycelia and plant roots and micro-environment in the rhizosphere. Many small molecules and macromolecular organic substances are secreted into the rhizosphere soil. These secretions and volatile organic compounds play an active role in regulating symbiotic relationships and interactions with other organisms[8].

2.1 Physiological and biochemical researches about edible mycorrhizal fungi (EMF) In nutrition and physiological researches about edible mycorrhizal fungi, Su Kaimei etal.[4] believed that it is able to increase the success rate of isolated pure culture through improving the components of matsutake medium. According to overview of Tang Chao etal.[2], seven kinds of flavonoids including hesperidin, morin, Rutacenum and quercitrin can significantly promote the mycelial growth of Suillusluteus(L.:Fr.) Gray, while adenosine can promote the growth, branching and aggregation of S. luteus (L.:Fr.) Gray. Adding mannose and glucose to the medium can promote mycelial growth and increase the dry weight of mycelia. Likewise, adding D-isoleucine to the medium is favorable for the growth of myxomatis mycelia. D-isoleucine not only provides nutrients for mycelial growth, but also serves as a signal source for mycelial growth initiation[5]. There are many unclear points about the mutual recognition between edible mycorrhizal fungi and symbiotic plants, the signaling and the mechanism of sporocarp formation. Many mycorrhizal fungi, such as tubers, can not be purely cultured independently and must be relied on symbiotic plants to provide living substances.

Functional polypore Fomitiporiayanbeiensis (GenBank accession number KT861405, Fungal name accession number FN570360) is a new polypore species discovered and developed by Editable Fungi Institute, Shanxi Academy of Agricultural Sciences. Produced in Yanbei area of Shanxi Province, it contains rich nutrients and many kinds of amino acids, has certain medicinal value, so it is significant to carry out artificial domestication and cultivation. In addition, wild edible fungus resources such as Tricholoma matsutake, Boletus edulis, Poriacocos (Schw.) Wolf, and Polyporus umbellatus are edible mycorrhizal fungus resources in Shanxi and have broad development prospects.

2.3 Researches about domestication and cultivation of edible mycorrhizal fungi Edible mycorrhizal fungus resources are rich and widely distributed, but they are symbiotic nutritive fungi, at present it is still not able to cultivate according to saprophytic edible fungus cultivation methods and techniques. Cultivation of edible mycorrhizal fungi depends on host plants, suitable soil, climate and other ecological conditions. Thus, there is still a great difficulty and challenge in domestication and cultivation. In the world, cultivation and development of edible mycorrhizal fungi mainly rely on mycorrhized seedlings to simulate the appropriate natural growth and ecological conditions of mycorrhizal fungi, establish natural plantations, semi-artificial cultivation or imitating wild cultivation, this approach has achieved a great breakthrough in cultivation of a variety of edible fungi. Fu Shaochun etal.[9] bred mycorrhizal seedlings of Pinusmassoniana and Boletusedulis Bull., and explored the effects of substrate, seedling age and inoculation on the formation of symbiont.

The most prominent feature of edible mycorrhizal fungi is that mycelium of edible medicinal fungi and symbiotic plant roots form symbiotic mycorrhizal fungi. Mycelia grow and development and form sporocarp through absorbing nutrients generated from plant photosynthesis. Besides, plants absorb the nutrients in the soil through their mycelium. Therefore, the symbiotic relationship is formed between the fungi and plants. Most of mycelia of edible mycorrhizal fungi are quite difficult to be cultured independently and need to be co-cultured with plant roots. However, the symbiotic microenvironment is very complicated. Most of their symbiotic mechanisms have not been made clear.

3 Prospects for development of edible mycorrhizal fungus in Shanxi Province

土地承包有效期的迫近，导致土地流转有效时期缩短，部分经营主体无法长期转入土地，潜在生产能力难以发挥出来。土地流转的市场价格形成机制复杂，缺乏必要的制度性约束。久而久之，许多农户的转入意愿难以实现，土地规模经营及其一、二、三产业的融合都受到了严重制约。

Edible mycorrhizal fungi include many species from the genus Amanita, Boletus, Cortinarius, Mycena, Tuber, Russula, and Tricholoma. Representative edible mycorrhizal fungi distributed in east Asia include Tricholomamatsutake (S. Ito & S. Imai) Singer, Suillusplacidus (Bonord.) Singer, Russula delica Fr., Russula. virescens (Schaeff.) Fr., Tuberindicum (Cooke & Massee), Boletusedulis Bull., Cantharelluscibarius Fr., Lactariusdeliciosus (L.) Gray, and 3/4 of them are symbiotic with different coniferous trees, while others are symbiotic with birch, evergreen chinquapin, casuarina, eucalyptus, oak and poplar.

With Taihang Mountain as the natural barrier, Shanxi Province has a complex terrain. In Shanxi Province, there are various landform types such as mountains, plateaus and basins. In the east of the mainland, it is not affected by the sea wind, forming the strong continental climate. In addition, due to the attack of winter cold air mass from Inner Mongolia, the northern part of Shanxi is relatively cold, thus forming a temperate continental monsoon climate with long, cold and dry winter, and short, hot and rainy summer. These complex landforms, diverse forest types, soil types and unique vertical climatic conditions have given birth to abundant resources of wild edible fungus resources and laid a good foundation for the development of wild edible fungus resources.

类似“病一病儿、笑一笑儿、坐一坐儿、煞一煞儿”这样固定格式的动词重叠儿化结构，在表示时间短的同时，又具有缓和、委婉的语气，具有使语言更加口语化的作用。其他如：理一理儿、冷一冷儿、润一润儿、动一动儿、想一想儿……

本试验以腌制好的鸡翅直接用热风模式220℃烧烤为对照组(Roast)；分别用60℃蒸汽、70℃蒸汽和80℃蒸汽烹饪30min后，再用热风模式220℃烧烤为试验组，简称分别为SV60+Roast，SV70+Roast，SV80+Roast，研究蒸汽低温烹饪对烤鸡翅食用品质的影响。试验设计如表1所示。

Artificial cultivation of edible fungi is a green industry. It does not compete with people for grain, not compete with people for land, not compete fertilizer with land, not compete with farmers for time, and not compete with other industries for resources. In recent years, the rapid development of edible fungi cultivation in various parts of Shanxi Province has accelerated the pace of technological innovations in industry. However, the mismatch with the research and innovation of edible fungus resources in Shanxi Province has lagged behind in the selection and breeding of cultivars, mainly in the following aspects : inadequate resource research, weak breed selection and breeding, few self-breeding varieties, chaotic supply of species and imperfect systems. The main cultivated edible fungi in Shanxi Province include Pleurotusostreatus, Agaricusbisporus, Lentinusedodes, GanodermaLucidumKarst, PleurotusferulaeLanzi, and Auriculariaauricular. Due to the special geographical environment and climatic conditions in Shanxi Province, the harvest period of edible and medicinal fungi complement with the harvest period of the whole country, making Shanxi Province become an important base for supply of edible fungi in China, which is also a powerful bright spot in the development of edible medicinal fungi in Shanxi Province.

Shanxi Province has excellent natural conditions for cultivation of edible fungi, cool summer is very suitable for physiological demands of low-temperature edible fungi. Agricultural ecological types available for production are various. Raw materials such as corn cob, corn stalks, cow dung resources are rich and cheap, and labor costs are much lower than developed areas. The departments at all levels have realized that the development of edible fungus industry plays an important role in upgrading the edible fungus industry through adjusting agricultural structure, increasing agricultural efficiency, increasing farmers’ income, and promoting employment of rural labor, so as to provide an excellent opportunity for upgrade of the edible fungus industry.

In recent years, our institute has undertaken more than 40 research and development projects. In the research and development of edible and medicinal fungus resources, especially the collection and preservation, evaluation and utilization of edible mycorrhizal fungus resources, we have established a collection, development and utilization platform for wild edible fungus resources. At present, we have collected more than 300 kinds of wild fungi and separated and stored strains (50 kinds of mycelia that can be cultivated), and discovered and developed the functional polypore F. yanbeiensis, and now we are carrying out functional analysis and application experiment. In special research project of seed industry in Shanxi Province, we are establishing the edible fungus germplasm resources evaluation system and application platform, collecting and domesticating wild fungus resources and utilizing and studying more than 100 kinds of resources, and we will continue to undertake the species evaluation and functional analysis. Besides, we will undertake variety breeding and industrialized cultivation research projects for main edible fungi, make comparative experiment for collected domestic and foreign varieties and screened strains (about 300 strains). On this basis, we will make innovative breeding and cultivation technique researches. Therefore, in order to strengthen the investigation and research on wild edible and medicinal fungus resources in Shanxi Province, including edible mycorrhizal fungi and the development of functional edible fungi, we should energetically develop production of edible and medicinal fungi and innovation of special products, which will make a great contribution to the new nutritional food source and health food source in China or even the whole world.

References

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