药用真菌猪苓菌核共生蜜环菌类群的研究

Polyporus umbellatus are tranditional Chinese edible and medicinal fungi. Its fruit body are edible and sclerotia are used as medicine.It is now clear that nutritution for sclerotial growth of P.umbellatus are supplied by Armillaria spp. However, few researches about which species of Armillaria associated with scleortia of P. umbellatus are carried out. The name of Armillaria mentioned in research articles and books of P. umbellatus was Armillaria mellea or Armillaria sp. Our previous research result suggested that the Armillaria species associated with sclerotia of P. umbellatus from different geographic regions are quite different. For lack of related researches, Armillaria species used in sclerotial cultivation of P. umbellatus are confused, which limitted the development of cultivation of P. umbellatus. In this research proposal, we are planning to isolate and identify the Armillaria species associated with sclerotia of P. umbellatus, analyze the phylogenetic relationship between Armillaria spp. and P. umbellatus and relationship between Armillaria spp. and content of main component in sclerotia of P. umbellatus, and compare biological characteristics of all the Armillaria isolates. This project will answer the question of Armillaria species associated with sclerotia of P. umbellatus, and provide more necessary information for better understanding the biological characteristics of P. umbellatus. The prospective results are of imporant value for selection of Armillaria species in cultivation of sclerotia of P. umbellatus. The Armillaria isolates in this project can also be used in its original habitats for cultivation of sclerotia of P. umbellatus.

猪苓是我国传统的药食两用真菌，其子实体可食，菌核入药。现已明确，猪苓菌核生长所需的营养均靠蜜环菌提供。一直以来有关猪苓菌核共生蜜环菌的种性鉴定还鲜有报道，在众多猪苓的研究文献及专著中提到的蜜环菌均为Armillaria mellea或Armillaria sp.，而我们的前期研究结果表明不同地域的猪苓菌核共生的蜜环菌种性存在较大差异。由于缺乏相关研究，当前猪苓菌核栽培中使用的蜜环菌来源混乱、种性不明，对猪苓的栽培生产造成一定影响。在本项目中，我们拟对不同地域的猪苓菌核进行共生蜜环菌的分离及鉴定；分析蜜环菌类群与猪苓系统发育和主要成分含量是否存在相关性；并对分离到的蜜环菌进行生物学特性比较研究。本项目将是对猪苓菌核共生蜜环菌种性问题的一个突破，亦是对猪苓生物学特性的必要补充；相关研究结果对不同地域栽培猪苓时蜜环菌种类的选择具有重要的理论指导作用；所获得的蜜环菌菌株亦可应用到猪苓的原生态栽培。

药用真菌猪苓，其菌核入药在我国已有2000多年的历史，具有利水渗湿的功效，为我国历次药典所收录。已有研究表明，猪苓的生长离不开蜜环菌，其生长所需的营养主要靠蜜环菌提供；然而人们对猪苓菌核共生的蜜环菌类群还知之甚少。为了解猪苓菌核共生蜜环菌的种性特征，在本项目中，我们共从全国11个省份采集到48份野生猪苓样品中成功分离出47株蜜环菌，46个菌株可划归至5个系统发育支系，并新确认1个新的支系。进一步研究发现：亲缘关系越近的猪苓更倾向于与亲缘关系越近的蜜环菌类群共生，蜜环菌的系统发育关系介导了猪苓与蜜环菌共生关系形成过程中的相互选择；猪苓菌核多糖的含量与土壤全N、全P有一定的相关性，而麦角甾醇的含量则与土壤全N有一定的相关性，未发现蜜环菌的系统发育型与猪苓的主要成分含量之间存在明显的相关性；有3个系统发育支系的蜜环菌既可以和天麻共生，也可和猪苓共生；本研究中所获得的蜜环菌依据主要的表型性状可划分为8个不同的形态型，不同形态型的蜜环菌之间具有不同的培养特性及胞外酶活性。本研究中所获得的不同地域来源的蜜环菌菌株今后可以应用到猪苓的原生态栽培中；相关实验的基础数据，可为猪苓栽培中蜜环菌的选择提供理论参考。