A new Leptographium species from the roots of declining Pinus sylvestris in Switzerland          下载免费PDF全文

S. Marincowitz  T. A. Duong  U. Heiniger  B. D. Wingfield  M. J. Wingfield  Z. W. de Beer 《Forest Pathology》2017,47(4)

Scots pine (Pinus sylvestris) trees have been declining in the Rhône valley, Switzerland, for almost three decades. In an assessment of the role of fungi in this syndrome, the dominant fungus isolated from stained roots was a Leptographium species, morphologically similar to the asexual state of Grosmannia serpens. We examined isolates of this fungus based on DNA sequences of four protein‐coding genes including actin, β‐tubulin, calmodulin and translation elongation factor‐1 alpha. The results showed that they were of a distinct, undescribed taxon related to species in the Grosmannia serpens and G. wageneri complexes. The fungus, described here as Leptographium rhodanense sp. nov., resembles other species in the two species complexes morphologically, and most probably ecologically, as is suggested by the fact that it was isolated from stained pine roots.  相似文献   

Underground communication of root hormones by common mycorrhizal network between trifoliate orange and white clover     

Qiang-Sheng Wu  Yi-Can Zhang  Ze-Zhi Zhang  Anoop Kumar Srivastava 《Archives of Agronomy and Soil Science》2017,63(9):1187-1197

Common mycorrhizal network (CMN) links up several coexisting plant individuals via underground root communication for resource sharing, while it is not known whether phytohormones participate in such communication. A two-chambered rootbox separated through 37-μm mesh was used to establish the CMN by Diversispora spurca between trifoliate orange (TO) and white clover (WC). After 20 weeks of inoculation, the CMN was established, as evident from high mycorrhizal buildup under supplier (mycorrhizal inoculation) TO–target (non-mycorrhizal inoculation) WC association. This CMN was eventually responsible for the significant increase in plant biomass of these associated plants. CMN decreased root abscisic acid (ABA) level in supplier and target plants, but increased root indole-3-acetic acid (IAA) level in supplier plant alone. CMN mediated significantly higher gibberellins (GAs) and zeatin riboside (ZR) concentration in roots of target plant, leaving supplier plant unaffected. Root ZR was bidirectionally transferred through the CMN. A higher root methyl jasmonate (MeJA) concentration was observed in supplier WC–target TO or supplier TO–supplier WC association, indicating an unidirectional communication from WC to TO. It suggested that except IAA, GAs, brassinosteroid (BR), and ABA, root MeJA and ZR were apparently involved in the underground communication by CMN.  相似文献   

低温下五种碳源对平菇菌丝生长和三种胞外酶活的影响     

李树林  赵士杰  吴龙  郑红丽  高翔 《内蒙古农业大学学报(自然科学版)》1999,(1)

本研究表明,在低温下供试碳源中,可溶性淀粉是平菇菌丝生长的最好碳源,其次是麦芽糖和葡萄糖。不同碳源对平菇胞外多酚氧化酶,愈创木酚氧化酶和漆酶酶活及３种酶总酶活的影响不同。前６周在麦芽糖基质中３种酶总酶活最高。８周时在可溶性淀粉基质中最高。其中１号菌株在甘露醇基质中漆酶酶活最高,２号菌株在麦芽糖基质中漆酶酶活最高。这３种酶与基质中木质素降解密切相关,故在低温下以淀粉为主,搭配麦芽糖等其它碳源,不仅利于平菇菌丝生长,更利于其３种酶活的稳定上升和木质素的快速降解,为子实体的发育积累更多营养。  相似文献   

三唑类杀菌剂对苹果轮纹病菌超微结构的影响     

侯珲  周增强  王丽 《中国农学通报》2017,33(12):103-107

为了研究三唑类杀菌剂对苹果轮纹病菌形态和结构的影响,选择在生产上常用的防治苹果轮纹病的三唑类杀菌剂:戊唑醇和苯醚甲环唑,对苹果轮纹病菌进行处理。用光学显微镜和扫描电镜技术研究新型三唑类杀菌剂对苹果轮纹病菌发育的组织学和超微形态结构的影响。结果表明:光学显微镜和扫描电镜观察发现三唑类杀菌剂处理能导致苹果轮纹病菌发生一系列变化:菌丝的生长明显受到抑制,不再匍匐生长,而是向上生长。菌丝干瘪、畸形,分枝增多,分枝有长有短,很不规则,且不均匀膨大。一些菌丝出现不同程度的龟裂现象。这些变化会导致苹果轮纹病菌菌丝的生长严重受阻,最终菌丝细胞解体死亡。  相似文献   

中国东北地区5个常见蜜环菌生物种的培养特性     

孙立夫  田淑敏  杨国亭  赵俊  秦国夫  宋玉双  宋瑞清 《东北林业大学学报》2007,35(2):48-51

选择马铃薯-葡萄糖、松膏Ⅰ、松膏Ⅱ、ShawⅢ和MS共5种培养基,分别对中国东北地区5个常见蜜环菌生物种的单倍体和双倍体菌株进行培养特性研究。结果表明:5个蜜环菌生物种在5种培养基上的菌落形态和颜色以及培养基颜色变化等方面表现大同小异。单倍体菌落颜色基本为白色,有菌索产生的菌落易变成浅褐色;双倍体菌落基本上为浅褐色或褐色,壳皮状,随着菌丝生长和菌索形成能力的提高,菌落的颜色也表现出越来越深的趋势,绝大多数培养基不变色。5个生物种单双倍体菌株间在菌丝生长和菌索形成方面存在变化,双倍体菌株的菌丝生长速度普遍要比单倍体菌丝快,且菌索形成的能力也明显增强,菌丝生长良好的则菌索形成能力也相对较强;每个生物种不同交配类型的单倍体菌株间在同一种培养基上也基本表现相同。在5种培养基中,两个松膏培养基对促进菌丝生长和菌索的形成是最佳选择,其次是ShawⅢ培养基,再次是PDA培养基,而MS培养基则最差。  相似文献   

VA菌根真菌对植物养分吸收与传递的影响   总被引：19，自引：0，他引：19  

曾曙才  苏志尧  陈北光  俞元春 《西南林学院学报》2005,25(1):72-75

VA菌根是泡囊-丛枝内生菌根菌与高等植物根系形成的共生体.VA菌丝增加根系的吸收面积,促进植物对矿质养分(尤其是磷和微量元素)的吸收,增强植物抵抗养分胁迫的能力,减少氮、磷肥的使用量和流失,从而避免水体富营养化.VA菌丝可以形成菌丝桥,在不同植株间传递养分,成为生态系统养分循环的重要通道.  相似文献   

丛枝菌根真菌的外生菌丝对土壤水稳性团聚体形成的影响   总被引：28，自引：1，他引：28  

冯固  张玉凤等 《水土保持学报》2001,15(4):99-102

应用三室根箱装置 ,研究了接种丛枝菌根真菌 Glomus mosseae和 Glomus versiform对玉米根分泌物以及菌根真菌外生菌丝对沙土的水稳性大团聚体形成的作用。结果表明 :接种 Glom us mosseae和 Glomus versiform提高了玉米根系分泌物的总量 ,进而增加了根系粘结的土壤重量。菌根菌丝对土壤中 5～ 2 mm水稳性大团聚体形成的贡献为 10 0 % ;在土壤中菌根菌丝的密度分布与 2～ 1mm水稳性团聚体的含量分布是一致的 ,都表现出随着距离根系表面距离的增加而增加的趋势。这些结果说明菌根菌丝直接促进了土壤团聚体的形成 ,对 5～ 2 m m水稳性大团聚体而言 ,没有菌根菌丝的作用就不能形成 ;菌根菌丝对 5～ 2 mm和 2～ 1m m水稳性团聚体的形成主要是通过其分泌物粘结和菌丝网络对土壤的缠绕作用所致 ,菌根菌丝对这两种水稳性团聚体形成的贡献甚至超过了根系的作用。  相似文献   

羊肚菌菌丝间融合与不融合现象研究     

贺新生  赵苗  王亚洲  张能  谭仁豪  王银  竹文坤  陈波 《食药用菌》2019,(4):244-252

用平板、空试管、断培养基等方法培养羊肚菌菌丝,在显微镜下原位直接观察菌丝间的融合和非融合现象。观察六妹羊肚菌Morchella sextelata、梯棱羊肚菌M. importuna、七妹羊肚菌M. septimelata、Mel-21和秋天羊肚菌M. galilaea、Mes-16、Mes-19、Mes-20、Mes-21等9个物种,共100多个菌株菌丝间2 000多个接触点;并历经6年时间,用300多个菌株在国内外100多个地点超过500公顷面积进行出菇试验。结果发现:同一单孢菌株的菌丝分枝间有少量部位的可自体融合,融合点不产生新的分枝菌丝;同一物种的不同单孢菌株间菌丝不融合,同一物种的多孢菌株培养物内部相互不融合;不同物种间的菌丝都不融合;不融合的菌丝接触点出现Ⅱ型、X型、Y型、T型、π型等状况交叉而过,细胞接触而不融合;未见菌丝间的有性融合;菌丝接触后出现死亡、缠绕、卷曲、打结、膨大等现象;羊肚菌菌丝体纯培养物可以形成分生孢子和菌核。出菇试验结果表明,腐生型羊肚菌物种的出菇率,超过200个单孢菌株100%,超过100个多孢菌株100%,超过50个纯组织分离物小于50%,超过30个组孢混合菌株小于50%;出菇菌株在形态和产量有显著差异。共生型羊肚菌的菌种都不出菇。能出菇的同一物种的多孢菌株出菇后表现出子实体形态多样性,不同物种混合播种后出菇的子实体为原来物种的形态特征。结论:羊肚菌单孢培养物菌丝间不发生有性融合,单个孢子自身可孕,完全能够单孢出菇。  相似文献   

辣椒丛枝菌根真菌吸磷机制研究     

M. SHARIF  N. CLAASSEN 《土壤圈》2011,21(4):502-511

A pot experiment was conducted to investigate the action mechanisms of arbuscular mycorrhizal (AM) fungi in phosphorus (P) uptake of Capsicum annuum L.in a sterilized fossil Oxisol.Three P levels of 0,10 and 200 mg kg-1 soil (P0,P10 and P200,respectively) without and with AM fungal inoculation were applied as Ca(H2PO4)2·H2O.Shoot dry matter yields and shoot P uptake increased significantly (P > 0.05) by the inoculation of AM fungi at P0 and P10.Root length and P concentration in soil solution increased with the inoculation of AM fungi but the root:shoot ratio decreased or remained constant.Around 50% roots of inoculated plants were infected by AM and the external hyphae amounted to 20 m g-1 soil at P10 and P200.The hyphae surface area of the infected root cylinder amounted to 11 and 2 cm-2 cm-2 root at P0 and P10,respectively.The increased P uptake of inoculated plants was mainly because of an up to 5 times higher P influx of the infected root.Model calculations showed that the root alone could not have achieved the measured P influx in both infected and non-infected roots.But the P influx for hyphae calculated by the model was even much higher than the measured one.The P uptake capacity of hyphae introduced in the model was too high.Model calculations further showed that the depletion zone around roots or hyphae was very narrow.In the case of the root only 7% of the soil volume would contribute P to the plant,while in the case of hyphae it would be 100%.The results together with the model calculations showed that the increased P uptake of AM inoculated plants could be explained partly by the increased P concentration in the soil solution and by the increased P absorbing surface area coming from the external hyphae.  相似文献   

接种丛枝菌根真菌对土壤水稳性团聚体特征的影响   总被引：5，自引：0，他引：5  

彭思利  申鸿  郭涛 《植物营养与肥料学报》2010,16(3):695-700

为了研究接种丛枝菌根真菌对土壤团聚体特征的影响,采用盆栽试验,以小麦(Triticum aestivuml)为宿主植物,在两个不同供磷水平条件下,分别接种丛枝菌根真菌Glomus intraradices和Glomus mosseae,收获后分析土壤团聚体数量、分布和分形维数,并运用通径分析对不同作用因子进行统计。结果看出,与对照相比,接种丛枝菌根真菌显著提高了土壤中有机质含量、球囊霉素相关土壤蛋白含量,土壤水稳性大团聚体数量也显著增加。接种处理提高了土壤的平均重量直径、几何平均直径,而且降低了土壤分形维数。通径分析表明,在影响土壤水稳性大团聚体的众多因子中,菌丝密度具有最大的作用,且以直接作用为主;有机质和球囊霉素相关土壤蛋白也表现出较大的作用。接种G. mosseae对改良土壤结构的作用优于接种G. intraradices。  相似文献