印度东北部黄兰种植区丛枝菌根真菌的侵染和分布(英文)

调查了印度东北部梅加拉亚邦(Meghalaya)3个黄兰种植区(Umdihar,Umsaw和Mawlein)内丛枝菌根真菌和暗隔真菌的侵染。分离和鉴定了丛枝菌根真菌孢子,根据不同黄兰种植区内菌根菌种分布和丰富度评价了菌根菌多样性和寄主选择性。结果表明,丛枝菌根真菌侵染显著高于暗隔真菌。丛枝菌根真菌和暗隔真菌的侵染分别是50.91%～58.95%和1.84%～4.11%。真菌孢子密度在三个种植区内变化较大(p0.05)。在所鉴定的7个属29个菌种中,球囊霉属菌种的丰富度最高。Sorenson系数在0.35-7.0之间。种植区内菌种丰富度在2.0～2.9之间。总的菌种丰富度与总的相对丰富度显著相关(p=0.001)。真菌分布、相对丰富度和主成分分析结果表明,大果球囊霉(Glomus macrocarpum)、Glomus multicaulic、缩不囊霉(G.constrictum)和无梗囊霉是黄兰最偏好的菌种,可能是由于寄主的营养获得和生长较为适当。图6表5参27。     

矿区排土场土壤中丛枝菌根真菌对刺槐接种效应

土壤中丛枝菌根真菌促进植物对矿质营养和水分的吸收,可以增强宿主植物在逆境条件下的生存能力。利用丛枝菌根真菌与宿主植物共生关系,在以矿区排土场土壤为基质的盆栽试验条件下,向刺槐幼苗接种供试丛枝菌根真菌(摩西球囊霉Glomus mosseae、象牙白多孢囊霉Diversispora eburnea、隐类球囊霉Paraglomus occultum及3种真菌的混合菌剂),验证丛枝菌根真菌对刺槐生长的影响。结果表明,接种供试丛枝菌根真菌能显著提高刺槐幼苗生物量和叶绿素含量,其中以接种摩西球囊霉组植株菌根侵染率、株高、地径、生物量和SPAD值最高,说明供试菌剂中摩西球囊霉与刺槐幼苗根系的亲和力最高,接种效应最显著。研究结果为菌根技术在矿区土地复垦中的应用提供参考。     

印度西高止山药用植物丛枝菌根真菌多样性

调查了印度西高止山脉南北Goal区内25个科的36种药用植物的丛枝菌根真菌多样性。30个物种带有丛枝菌根真菌,其余6个物种没有丛枝菌根真菌定植。在根际士壤中,共发现了来自5个菌属（球囊霉属、无梗囊霉、盾巨孢囊霉、巨孢囊霉属和Ambispora）的42种丛枝菌根真菌。本研究区内,球囊霉属是优势属,聚线绣球菌是优势种。定植百分比和孢子密度间存在显著负相关。南、北Goa区内,Simpson和ShannonWeiner多样性指数差异不显著,说明该区具有稳定、多样的植物群落。     

丛枝菌根真菌对紫穗槐固氮能力的影响

通过对紫穗槐双接种丛枝菌根真菌和根瘤菌、单接种丛枝菌根真菌、单接种根瘤菌、非接种对照处理,研究丛枝菌根真菌时紫稳槐固氮能力的影响.结果表明:选用的丛枝菌根真菌(Glomus intraradices)能够与紫穗槐很好地形成共生复合体,双接种丛枝菌根真菌和根瘤菌处理的苗木根系结瘤数量显著提高,苗木根系土壤的脲酶活性、叶片硝酸还原酶活性显著提高;通过对紫稳槐植株和土壤氮素含量的测定,进一步证实丛枝菌根真菌能够增强豆科树种紫穗槐的固氮能力.     

陕西省咸阳地区林木VA菌根真菌资源调查

通过对陕西省咸阳地区16种林木VA菌根研究,从根际土壤中分离鉴定出VA菌根真菌17种。其中无梗囊霉属1种,球囊霉属16种,球囊霉属为广谱性菌根真菌,摩西球囊霉、地表球囊霉,地球囊霉为常见种,本文还分析了VA菌根真菌与宿主植物的选择性及其分布规律。     

桃棕苗期接种丛枝菌根菌效应研究

以桃棕哥斯达黎加San Carlos种源及14152号家系幼苗为宿主,开展接种丛枝菌根真菌(地表球囊霉、苏格兰球囊霉和木薯球囊霉)的试验研究.结果表明:参试的3个丛枝菌根真菌均可在桃棕San Carlos种源和14152号家系上形成感染,感染率26.7%～50.0%,感染指数13.3～37.5.尽管形成了菌根感染,但接种后7个月时,对桃棕San Carlos种源和14152号家系的地上部分的生长均未产生显著的影响;菌根接种对14152号家系根系的生长产生显著的促进作用(P＜0.05).木薯球囊霉G3008菌株接种处理下,14152号家系幼苗根系生物量和主根长分别比不接种(对照)提高了80.0%和51.4%.3个丛枝菌根菌中,木薯球囊霉G3008菌株对桃棕家系苗期根系发育有较好的效果.     

云南不同栽培区油橄榄的丛枝菌根研究

为探索云南不同栽培区油橄榄的丛枝菌根状况,在云南省3个主要的油橄榄引种栽培区即永仁、丽江和昆明的油橄榄种植园,选择4年生油橄榄幼树为研究对象,采用形态学的研究方法,对该树种的丛枝菌根(AM)状况和土壤中丛枝菌根真菌(AMF)的孢子数量和群落组成进行了研究。结果发现,3地种植园的油橄榄植株根系均有AMF的定殖,根系中AMF的总定殖率分别为47.11%、71.79%和87.15%,孢子密度依次为300.22个/20g土、702.56个/20g土和489.75个/20g土。统计分析表明,根系AMF总定殖率昆明显著高于丽江,丽江显著高于永仁(p0.05),3地根际土壤中AMF孢子密度差异显著。从永仁、丽江和昆明油橄榄的根际土壤中分离到的AMF孢子种类分别为6种、4种和4种,大果球囊霉是3地共有AMF优势种;永仁样地AMF类群显著不同于昆明和丽江两个样地,与两地的AMF群落相似性Sorenson’s系数均为0.2;昆明和丽江两地的共有种除大果球囊霉以外,还有缩球囊霉和根内球囊霉,两地的Sorenson’s系数达0.75。     

重庆植烟区丛枝菌根真菌资源调查及初选分析

对重庆市主要植烟区连作烟田丛枝菌根真菌资源进行了调查,鉴定分析了烟草丛枝菌根真菌共7属32种,包括球囊霉属(Glomus)18种(包括新种1个),无梗囊霉属(Acaulospora)7种,内养囊霉属)1种,盾巨孢囊霉属(Scutellospora)1种,巨孢囊霉属(Gigaspora)1种,原囊霉属(Archaespora)2种,近球囊霉属(Paraglomus)2种。其中,球囊霉属(Glomus)的根内球囊(G.intraradices)和摩西球囊霉(G.mosseae)为烟草丛枝菌根真菌的优势菌种。     

紫背天葵丛枝菌根真菌多样性研究

紫背天葵（Begonia fimbristipula）是集营养保健和特殊风味为一身的野生高档蔬菜之一,也是 南方传统中药材,但人工栽培尚存在较大的技术障碍。以紫背天葵为研究对象,对分布于广西壮族自治 区贺州市姑婆山国家森林公园的野生植株根际土丛枝菌根真菌（Arbuscular Mycorrhiza Fungi,AMF）孢 子、菌根侵染率和土壤营养元素等开展研究,以期对后期的菌根化栽培提供技术支撑。结果表明：紫背 天葵根际土中AMF 种类丰富,孢子密度大,菌根侵染率较高,共统计真菌孢子26 种,主要属为球囊霉 属（Glomus）、无梗囊霉属（Acaulospora）、盾孢囊霉（Scutellospora）和巨孢囊霉属（Gigaspora）;根际 土孢子密度和菌根侵染率在不同采样点间存在显著性差异,而且均与土壤的全K 含量呈负相关,与交换 性Ca 含量呈正相关,另外,AMF 孢子丰富度与速效K 呈负相关,菌根侵染率与有机质含量呈正相关。 可见紫背天葵野生根际土的真菌孢子在K 含量较低时,多样性较高,主要为球囊霉属和无梗囊霉属的种 类。     

山西历山自然保护区沙棘丛枝菌根真菌(AMF)资源的调查

通过对山西历山自然保护区沙棘根际的丛枝菌根真菌资源进行了调查。从沙棘的根际土壤中共分离鉴定出7种丛枝菌根真菌的孢子，分别为孔围球囊霉、摩西球囊霉、地表球囊霉、集球囊霉、地球囊霉、缩球囊霉、单孢球囊霉，其中，孔围球囊霉为国内新记录种，摩西球囊霉为优势种。从而为沙棘的丰产栽培、育苗及造林提供了理论依据。     

Augmented growth of long pepper in response to arbuscular mycorrhizal inoculation

Arbuscular mycorrhizal (AM) technology is a soil-based fertilization practice for sustainable crop productivity. We evaluated six indigenous Arbuscular mycorrhizal fungi (AMF) strains for their symbiotic response with Piper longum (long pepper), a non-timber forest product holding promise as a commercial crop for its medicinal fruits and roots. Piper saplings were raised in a 10 cm thick sand and soil mix inoculated with various AMF. Under field conditions, plants inoculated with AMF demonstrated better survival (≥80%) than non mycorrhizal plants (58%). Almost all the studied AMF strains increased the plant growth, biomass and nutrient content (N and P) over the uninoculated control. Mycorrhizal inoculation with four AMF species, viz: Glomus fasciculatum, G. clarum, G. etunicatum and G. versiforme greatly enhanced long pepper growth both in the nursery and field conditions.     

Arbuscular mycorrhizal fungi communities associated with wild plants in a coastal ecosystem

Arbuscular mycorrhizal fungi(AMF) form a near-ubiquitous mutualistic association with roots to help plants withstand harsh environments,and play a key role in the establishment of coastal beach plant communities.Yet little is known about the structure and composition of AMF communities on coastal beaches of eastern China.In this study,we investigated the occurrence,community composition and diversity of AMF associated with common wild plants on a coastal beach of North Jiangsu,China.Almost all of the local wild species were colonized by AMF except for Chenopodium album L.Thirty-seven AMF species were isolated from the rhizosphere belonging to 12 genera in seven families.Glomus was the dominant genus and Funneliformis mosseae the dominant species.The colonization,spore composition and diversity of AMF were strongly related to edaphic factors.Sodium(Na~+) ions in the soil significantly and negatively affected the colonization rate by AMF and both soil Na~+ levels and pH had a significant negative effect on AMF spore density and evenness.However,there was a significant positive correlation between species richness and total organic carbon.The results provide insights into soil factors affecting native AMF communities in coastal beach habitats which could benefit vegetation recovery and soil reclamation efforts.     

广东清远石灰岩3个植物群落菌根及土壤AMF孢子多样性

以广东省清远市清新县石灰岩山区风水林、次生草坡和旱作耕地的退化植被群落为主要研究对象,比较研究了3个植物群落常见植物的菌根感染率和根际土丛枝型菌根真菌(AMF)孢子的密度和丰富度。结果如下:在所检测的29种常见植物中,除凹头苋(Amaranthus blitum)外,其余植物均具有典型的丛枝型菌根结构;次生草坡植物的菌根感染强度和频度均较高,风水林次之,旱作耕地杂草的菌根感染强度和频度相对较低;在3个植物群落土样中共分离出70种AMF孢子,以球囊霉属(Glomus)最为丰富,无梗囊霉属(Acaulospora)次之;林相保护较完整、植物较丰富的风水林拥有最丰富的AMF孢子类型和最高的密度,而结构退化、物种贫乏的次生草坡和旱作耕地中的AMF孢子类型少,密度也明显降低。研究表明植物群落的物种多样性与其根际土AMF孢子丰富度和多样性具有密切的联系。     

Biodiversity of arbuscular mycorrhizal fungi in Amygdalus scoparia Spach plantations and a natural stand

The biodiversity of arbuscular mycorrhizal fungi(AMF) was surveyed in the Kolm region of Iran in three adjacent sites, a natural stand, a 10-year-old and a 15-yearold plantation of Amygdalus scoparia. To date, there have been few studies of AMF biodiversity in Iran, especially in the western forests of the country. For this study, soil and root samples were taken from A. scoparia rhizosphere soil in spring and autumn. Almost half of the root length was colonized by AMF. We identified 13 AMF species belonging to Glomeraceae, Claroideoglomeraceae or Diversisporaceae. The three plantations differed in terms of soil electrical conductivity, organic C and P. Spore density was significant correlated with P concentration. Root length colonization was correlated only with soil Ca.Species diversity and richness were significantly correlated with soil N, P, organic C and spore density. AMF diversity in 15-year-old plantations was more similar to that in the natural stand than in the 10-year-old plantation. We confirmed that a 15-year-old plantation is not similar in terms of AMF colonization to natural stands. We conclude that more than 15 years are required for AMF colonization of plantations to resemble that of natural stands.     

不同套种模式云南核桃丛枝菌根与土壤因子的相关性研究

为探明不同套种模式核桃根际丛枝菌根(AM)与土壤因子之间的相关关系,采用菌根形态学的研究方法,研究了核桃根系中丛枝菌根真菌(AMF)定殖状况和根际土壤中AMF的孢子密度,运用相关分析、主成分分析和通径分析方法,研究了核桃AMF与土壤因子的相关性。结果表明:核桃根系能与AMF形成良好的共生关系,不同套种模式之间核桃根系中AMF定殖率以及孢子密度差异显著,套种茶树的种植园中AMF的侵染率和孢子密度最高,套种豌豆的种植园中AMF侵染率和孢子密度最低;AMF孢子密度与土壤有机质、pH值、碱性磷酸酶和脲酶活性显著正相关;AMF总侵染率与pH值显著正相关;AMF总侵染率、菌丝侵染率和孢子密度与全磷显著负相关;丛枝侵染率与全氮和碱性磷酸酶活性显著正相关;菌丝侵染率与pH值极显著正相关;菌丝圈侵染率与全氮和碱性磷酸酶活性显著正相关;泡囊侵染率与过氧化氢酶活性显著正相关,与水解氮和速效钾极显著负相关,与土壤有机质和全氮显著负相关。土壤中的有机质、全氮和全磷是云南高原山区核桃菌根真菌定殖和发育的主要影响因子。     

Disturbance changes arbuscular mycorrhizal fungal phenology and soil glomalin concentrations but not fungal spore composition in montane rainforests in Veracruz and Chiapas,Mexico

Mexican montane rainforests and adjacent disturbed areas were studied for disturbance-related spatio-temporal changes to the arbuscular mycorrhizal fungal (AMF) community and soil glomalin concentration. The AMF community functions to both improve plant growth and soil conditions and is thus an important component to the restoration of this forest type to disturbed areas. The study areas included mature rainforests that were converted to pine forests, milpas, pastures and shrub/herbaceous plant communities via burning and logging. Seasonal patterns in AMF spore species richness and sporulation significantly differed across disturbance types at two of the three sites surveyed. Contrasting patterns of sporulation among AMF families across different disturbance types helped to explain how species richness and composition were maintained despite dramatic changes to the host plant community. Meaning, in most cases, disturbance induced changes in when different AMF taxa sporulated but not what taxa sporulated. Only conversion from mature pine–oak–Liquidambar–Persea forests to pine-dominated stands severely reduced AMF spore richness and total sporulation. Surprisingly, in pine-dominant stands no concomitant negative impacts on soil glomalin (MAb32B11 immunoreactive soil protein) concentrations were detected. However, soils of mature forests containing no pines had the highest concentration of glomalin. Conversion to pasture and milpa (diverse cornfield) had a strong negative impact on the concentration of soil glomalin concentrations. In sharp contrast, the same disturbance types improved AMF sporulation and AMF spore richness. It appears that disturbance type, and not AMF community measures used herein, best predicts changes in soil glomalin concentration.     

Above- and belowground responses to tree thinning depend on the treatment of tree debris

Mechanical mastication is increasingly prescribed for wildfire mitigation, yet little is known about the ecological impacts of this fuels treatment. Mastication shreds trees into woodchips as an alternative to tree thinning and burning the resulting slash, which can create soil disturbances that favor exotic plants. Previous research on mastication has not simultaneously considered both the responses of soil organisms and understory plant communities. We compared mastication to slash pile burning (both 6-months and 2.5-years post-treatment) and untreated controls in pinyon–juniper (Pinus edulis–Juniperus osteosperma) woodland and measured soil properties, arbuscular mycorrhizal fungi (AMF) and understory plant composition. Our results showed that slash pile burns had severely degraded soil properties and low AMF abundance and richness compared to untreated or mastication plots. Pile burns were dominated by exotic plant species and had approximately 6× less understory plant abundance and richness than untreated plots. Only two variables differed between mastication and untreated plots 6-months post-treatment: mastication had lower soil temperature and higher soil moisture. Mastication plots 2.5-years post-treatment had more plant cover and richness than untreated plots or pile burns, although non-native Bromus tectorum cover was also greater and AMF spore richness was lower than untreated plots. The structural equation model (SEM) we developed showed that plant cover strongly influenced AMF abundance (0.50) and both plant cover (0.36) and AMF (0.31) positively influenced soil stability. In the short-term, mastication is a preferable method as it creates fewer disturbances than pile burning; however long-term impacts of mastication need further study as this practice could affect native plant communities. Our results suggest that the manner in which woody debris is treated following tree thinning has an important influence on soil stability and native plant biodiversity.     

Changes in forest vegetation and arbuscular mycorrhizae along a steep elevation gradient in Arizona

We assessed species composition, richness and abundance of understory vegetation, as well as arbuscular mycorrhizal (AM) inoculum potential on the San Francisco Peaks, tallest mountains in Arizona, crossing a steep, south-facing elevational gradient. These mountains have a high conservation value due to their rare habitats but previous vegetation studies have been limited. Because mature trees in the Pinaceae do not form associations with AM fungi, there may be more variation in plant community and AM fungal associations in coniferous forest than in ecosystems where all species associate with AM fungi. Differences in species composition between forest types reflected differences in the historical disturbance regimes. Species richness was highest in ponderosa pine forest (32.6 ± 1.4 per 1000 m² plot), although plant abundance was highest in aspen forest (49.4 ± 3.8%). Ponderosa pine and bristlecone pine forest were both high in species richness and contained species which were tolerant of frequent, low-intensity fire. Exotic species richness and abundance were highest in the lower elevations, which were also areas of high species richness and greater anthropogenic disturbance. Arbuscular mycorrhizal inoculum potential varied widely (1.2–80.1%), decreasing with increases in tree cover. We suggest indicator species that may be of use in monitoring these forests under changing climate and fire regimes.