大青山不同坡位柄扁桃根围土壤丛枝菌根真菌(AMF)群落结构

以大青山阳坡柄扁桃幼根及根围土壤为试材,采用Phillips和Hayman的染色、湿筛倾析-蔗糖离心及土壤理化因子常规测定方法,研究了不同坡位柄扁桃根围土壤丛枝菌根真菌(AMF)群落结构及其土壤理化因子,以期了解土壤理化因子对柄扁桃根围土壤AMF群落结构的影响。结果表明:不同坡位柄扁桃菌根侵染率在一定范围内随着海拔的升高呈先升高后降低的现象。在不同坡位柄扁桃根围土壤中共分离出12属33种AMF,其中Funneliformis mosseae和Rhizophagus intraradices属于优势种。下坡位和中坡位AMF的孢子密度显著高于上坡位(P0.05)。下坡位种的丰度和Shannon-Weiner指数均显著高于中坡位和上坡位(P0.05)。AMF多样性主要受土壤理化因子全磷、pH、速效钾、速效磷的影响。     

丛枝菌根真菌影响蔬菜品质研究进展

丛枝菌根（Arbuscular mycorrhiza,AM)真菌是一类具有重要生态意义和农业意义的微生物,它与宿主植物形成共生体后,能够显著改善宿主植物的营养。近年来研究表明,丛枝菌根真菌侵染蔬菜作物后还能明显改善蔬菜品质,其作用受到共生体系的种类、土壤理化特性和农艺措施的影响,其机制主要是蔬菜作物接种菌根真菌后,菌根真菌能改善宿主植物的养分状况,改变宿主植物的碳营养状况,影响宿主植物的酶代谢,改变植物的激素代谢及菌根真菌本身的异源作用。     

北京市松山国家级自然保护区典型植被群落的土壤微生物群落结构特征

土壤微生物群落结构是影响生态系统养分循环的重要因素之一。该研究选取北京市松山国家级自然保护区内胡桃楸阔叶林、蒙古栎阔叶林、油松针叶林、针阔叶混交林、灌丛和草甸6种典型植被类型下的土壤,基于野外调查、采样与实验室分析对不同植被类型下土壤微生物群落结构进行了研究。结果表明:胡桃楸阔叶林土壤细菌和真菌特有的OTUs和Alpha多样性均最高,细菌和真菌OTUs最低值则分别出现在针阔叶混交林和灌丛土壤,Alpha多样性最低值出现在蒙古栎阔叶林;土壤细菌群落主要为变形菌门(Proteobacteria)、放线菌门(Actinobacteria)和酸杆菌门(Acidobacteria),真菌群落以担子菌门(Basidiomycota)和子囊菌门(Ascomycota)为主。土壤pH、含水量和土壤温度会影响土壤细菌和真菌的丰富度与多样性。该研究为松山国家级自然保护区内土壤微生物资源保护及其生态功能的研究提供参考依据。     

不同氮肥及有机肥投入对设施番茄菜地AM真菌侵染势和空间分布的影响

在山东寿光一年两季设施番茄长期定位施肥试验的基础上,检测土壤中的AM真菌群落组成;并通过生物接种的方法,检测不同土层AM真菌侵染势(MIP),研究不同氮肥和有机肥投入对土壤中AM真菌繁殖体数量和生物效应的影响。结果表明,设施菜田中不同养分投入可在一定程度上改变土壤AM真菌群落结构,但仍能保持一定数量的AM真菌。施肥量的增加显著抑制了AM真菌侵染势,AM真菌在不同土层的空间分布差异不显著。     

浑善达克沙地榆AM真菌的空间分布及与土壤因子的相关性

为了探明浑善达克沙地榆AM真菌的生态分布规律和土壤因子的相关性及其在生态恢复中的作用,填补我国浑善达克沙地顶级群落榆树疏林在菌根真菌方面的空白。2016年10月在浑善达克沙地样地内采集沙地榆(Ulmus pumila var.sabulosa)5~30cm范围内根系和土壤,测定土壤养分含量、酶活性以及AM侵染率、孢子密度等,研究了浑善达克沙地榆AM菌根真菌(arbuscular mycorrhiza,AM)在不同样地和立地类型下的分布特征及与土壤因子之间的关系。结果表明:1)AM真菌能与沙地榆形成良好的共生关系,但分布具有空间异质性,菌根结构为Paris-type;2)正镶白旗、正蓝旗、克什克腾旗样地总侵染率平均值分别为71.86%、79.94%、71.74%,孢子密度平均值分别为3.99、7.02、1.90个·g-1,孢子密度和总侵染率均值为正蓝旗正镶白旗克什克腾旗,丘间地阴坡阳坡;3)孢子密度和总侵染率、易提取球囊霉素含量、碱性磷酸酶活性、过氧化氢酶活性呈极显著正相关,与总球囊霉素含量呈显著正相关,总侵染率与总球囊霉素含量、碱性磷酸酶活性呈极显著正相关,与过氧化氢酶活性呈显著正相关;4)第1、2主成分的累积方差贡献率达到65.663%,第1主成分中过氧化氢酶活性、易提取球囊霉素含量、速效钾含量、有机碳含量和碱性磷酸酶活性等土壤因子对决定土壤生态起主要作用。以上结果说明,浑善达克沙地榆与AM真菌可以形成良好的共生关系,侵染率与孢子密度具有空间异质性,并与土壤养分密切相关,这对进一步筛选和接种优势AM真菌具有重要意义。     

不同猕猴桃品种根际AM真菌多样性与土壤养分相关性分析

【目的】探明不同猕猴桃品种根际AM真菌的多样性、空间分布规律以及土壤养分的生态功能。【方法】于2014年7月在贵州省猕猴桃产学研基地采集4个猕猴桃品种(‘海沃德’‘红阳’‘金艳’‘黄金果’)根际0~10、10~20、20~40 cm 3个土层的土样和根样,采用碱解离-酸性品红染色法与湿筛-倾析-蔗糖离心法分别测定菌根侵染率、AM真菌孢子密度,并对AM真菌孢子进行形态学鉴定,研究AM真菌的侵染特性、物种多样性以及与土壤养分的相关性。【结果】‘海沃德’侵染率最高,为34.3%;‘黄金果’侵染率最低,为14.9%。共分离鉴定出AM真菌4属69种,其中球囊霉属(Glomus)39种,无梗囊霉属(Acaulospora)24种,盾巨孢囊霉属(Scutellospora)4种,内养囊霉属(Entrophospora)2种,优势种枫香球囊霉(Glomus liquidambaris)在4个猕猴桃品种各土层中均有分布;AM真菌孢子主要分布于10~20 cm土层,孢子密度与土层和速效磷呈显著正相关、与全氮呈极显著负相关、与p H呈显著负相关,种丰度的分布变化规律与孢子密度一样,0~20 cm土层AM真菌平均多样性指数最高。【结论】4个猕猴桃品种根系均能被AM真菌侵染,但侵染率较低,不同品种猕猴桃根际具有较丰富的AM真菌资源,AM真菌物种多样性具有明显的空间异质性,并与土壤养分密切相关,这为进一步筛选和接种优势AM真菌,促进猕猴桃引种栽培及产业化发展具有重要意义。     

低磷胁迫下接种土著和外来AMF对枳生长的影响

丛枝菌根真菌（arbuscularmycorrhi—zalfungi,AMF）促进共生植物磷吸收的现象,在不同的作物及生长环境中被广泛的证明。柑橘田间条件下根毛稀少,很大程度上依赖丛枝菌根（arbuscularmycorrhi-zae,AM）系统改善其对土壤养分和水分的吸收,尤其是对磷素的吸收;作为回报。     

甲壳素对葡萄园土壤微生物群落组成的影响

为明确甲壳素对葡萄园土壤微生物群落组成的影响,试验用甲壳素处理土壤为试验组,以不添加甲壳素处理为对照组,利用16S r DNA和ITS高通量测序分析土壤中的细菌与真菌群落组成。结果表明,试验组土壤中的细菌及真菌的物种丰富度、物种均匀度和物种多样性均显著高于对照组。说明甲壳素能明显改善葡萄园土壤的微生物群结构,促进养分分解,提高土壤质量,从而促进植株生长结果。     

接种AMF对葡萄微繁苗生长效应的研究

以葡萄为试验材料,在练苗期间接种AMF孢子菌剂,研究微繁苗移栽过程中AMF侵染过程,分析菌根化进程中微繁苗根系活力的变化以及AM共生体对微繁苗生长发育的促进效应。结果表明:AMF对葡萄微繁苗的生长发育具有重要促进作用,能够促进根系活力,微繁苗根系磷酸酶活性与AMF侵染率存在显著相关性。接种AMF可增强幼苗根系活力,促进根系对N、P等矿质养分的吸收和积累,并促进植株的光合作用,提高幼苗的生长势。     

荒漠草原四种常见植物群落土壤养分及土壤微生物特征

以宁夏盐池县典型的荒漠草原区为例,选取了该地区4种常见的植物群落,分析了不同植物群落土壤养分和土壤微生物的差异性及相关性。结果表明:不同植物群落土壤养分各指标均具有差异性。苦豆子群落土壤全氮、碱解氮含量相对较高,芨芨草群落土壤有机碳含量较高,油蒿群落土壤养分普遍较为贫瘠,盐爪爪群落土壤速效磷含量相对较高。4种植物群落土壤三大微生物数量在不同群落同一土层间、同一群落不同土层间均各具差异,但4种群落土壤微生物数量均表现为细菌放线菌真菌。4种植物群落土壤养分与土壤微生物各指标间相关性存在差异。苦豆子群落中各指标间关系最为密切,芨芨草群落次之,油蒿、盐爪爪群落各指标间关系较为复杂。由此,根据不同植物群落土壤养分、土壤微生物的特征,可为荒漠草原恢复与治理提供一定的参考依据。     

丛枝菌根真菌对番茄苗期生长及矿质营养吸收的作用

以烘干粉碎后的秸秆与灭菌后的土壤配制成栽培基质,接种5种丛枝菌根菌种接种剂进行番茄栽培试验。结果表明,各种丛枝菌根共生微生物接种后对番茄幼苗生长发育和矿质元素吸收有很好的改善和促进作用,特别是对P、K吸收作用显著,对番茄干质量有明显增加作用。通过对番茄菌根侵染情况分析发现根部丛枝菌根侵染率(F)以Glomusmosseae-1和G.mosseae-2最高,可达30%以上,而丛枝菌根形成率(a)则以G.mosseae-2最高,促进番茄生长效果最好的菌种亦为G.mosseae-2。     

Optimum Level of Nitrogen and Phosphorus to Achieve Better Papaya (Carica papaya var. Solo) Seedlings Growth and Mycorrhizal Colonization

An experiment under greenhouse conditions was carried out to evaluate the best level of nitrogen (N) and phosphorus (P), which promote the growth of papaya (Carica papaya L. var. Solo) seedlings without affecting the arbuscular mycorrhizal fungi (AMF) activity. Seedlings of papaya were transplanted to pots inoculated or not with Gigaspora margarita spores at four levels of N (0, 50, 100, and 200 ppm) and P (0, 25, 50, and 100 ppm). P was amended at the same time of pot filling up with substrate but N was applied weekly. The experiment was harvested after 100 days and plant dry weight together with AMF colonization was measured. The major response on the plant dry weight and height was from the fertilizers (N and P) where it proportionally increased. For the dry weight, at low amounts of nutrients the effects of AMF were greater, but as much as the fertilizer level in soil increased this response decreased. The colonization decreased as the nutrient levels increased, especially the P. The best combination of N and P for plant growth and AMF colonization could be at 50 and 25 ppm, equivalent to 5 and 2.5 kg/10a, respectively.     

丛枝菌根真菌促进植物抗重金属镉的研究进展

丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)是土壤中一类广泛存在的植物共生真菌,已有研究表明,AMF能够提高植物对重金属的抗逆性和耐受性。该研究从AMF与植物2个方面介绍了相关研究领域的前沿动态,旨在推进AMF促进植物耐受Cd机制的深入研究。在根外,丛枝菌根真菌能够直接吸收、固持Cd,以及改变植物根际的土壤微环境,从而影响Cd的形态和生物活性,增强植物对Cd胁迫的抗性。在根内,丛枝菌根真菌调节植物通过体内螯合、转运以及启动抗氧化防御系统等特定的生理生化过程,减少高浓度Cd对植物的胁迫和伤害。此外,丛枝菌根真菌还能通过促进植物生长来抵御Cd胁迫。     

蔬菜丛枝菌根真菌研究概况及进展

丛枝菌根真菌(AMF)是一类在自然界和农业生态系统中具有重要作用的有益微生物,它与宿主植物形成共生体后,能显著改善宿主植物的营养状况,从而提高作物的产量、品质和抗逆性。本文就蔬菜丛枝菌根真菌的研究历程、种类资源及其对蔬菜作物的生理效应和作用机制进行了简要综述,列举了丛枝菌根真菌在蔬菜生产应用上的部分实例,并对其应用前景进行了分析和展望。     

Effects of AMF inoculation on growth of Panax ginseng C.A. Meyer seedlings and on soil structures in mycorrhizosphere

We aimed to investigate the effects of inoculating Panax ginseng C.A. Meyer seedlings with arbuscular mycorrhizal fungi (AMF) by examining the root colonization, plant nutrition uptake, growth characteristics, and soil aggregation of P. ginseng seedlings inoculated at the time of transplantation. At 16 weeks, the AMF spore density per 30 g of fresh mycorrhizosphere in seedlings inoculated with AMF (AMF+ seedlings) was 256.8 and that in seedlings not inoculated with AMF (AMF− seedlings) was 186.3, respectively. The colonization rate of AMF in the lateral roots of AMF+ seedlings was approximately 19% higher than that in the lateral roots of AMF− seedlings. The patterns of AMF colonization in ginseng roots were similar to those of the Paris-type mycorrhizal association. Plant growth characteristics, such as plant height, root length, leaf area, number of lateral roots, fresh weight of shoots and roots, and chlorophyll content, were significantly enhanced in AMF+ seedlings compared to AMF− seedlings. The macronutrient content (P, K, and Ca) and micronutrient content (Cu, Fe, and Zn) of both shoots and roots were also significantly higher in AMF+ seedlings compared to AMF− seedlings. Furthermore, glomalin content and soil aggregation were significantly enhanced in AMF inoculated areas. Our results indicate that AMF inoculation may enhance the growth of ginseng seedlings by improving the uptake of mineral nutrients and the soil structure in mycorrhizosphere.     

非灭菌土接种AM真菌对油蒿抗旱性的影响

利用盆栽试验在正常水分和干旱胁迫条件下研究了非灭菌土接种AM真菌摩西球囊霉(Glomus mosseae)和土著AM真菌(Indigenous arbuscular mycorrhizal fungi)对油蒿(Artemisia ordosica)生长及抗旱性的影响。结果表明:干旱胁迫显著抑制了AM真菌对油蒿的侵染。无论在正常水分还是干旱胁迫条件下,接种AM真菌都增加了植株的分枝数、地上部鲜重和干重、地下部鲜重和干重,但没有明显提高株高、茎粗和改善组织水分状况;与未接种相比,干旱胁迫下接种土著AM真菌显著提高了根系氮、磷含量,提高了叶绿素、可溶性蛋白含量,增强了保护酶超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)的活性并降低了丙二醛的含量,因此增强了植物的抗旱性。     

Effects of pavements on diversity and activity of mycorrhizal symbionts associated with urban trees

This study investigated the impact of different types of soil sealing on the communities of a group of beneficial plant symbionts, arbuscular mycorrhizal fungi (AMF), colonizing the roots of two shade trees, Celtis australis and Fraxinus ornus, frequently grown in urbanized sites. Such plants were grown in an experimental site, in northern Italy, established in November 2011 and subjected to four different pavement treatments: impermeable monolithic asphalt, permeable pavers, permeable concrete and unpaved soil. The diversity and composition of root AMF communities were assessed by PCR denaturating gradient gel electrophoresis of partial 18S rRNA gene, AMF taxa were identified by amplicon sequencing and mycorrhizal colonization was evaluated after root clearing and staining. For the first time, our molecular work revealed that impermeable pavements induced shifts in the composition of AMF communities associated to the roots of C. australis and F. ornus and impacted on the percentage of mycorrhizal root length. When the root-zone was covered with permeable pavements, a similar AMF community as that observed in the unpaved soil was detected, providing novel information to be utilised for reducing the disturbance caused by specific types of soil sealing on AMF symbionts, which play a key role in plant nutrition and health. A total of 45 AMF sequence types were detected, with Sclerocystis and Septoglomus as the most abundant phylotypes, accounting for 84% of the sequences. The predominance of Sclerocystis species in the roots of both tree species under impermeable pavements indicated their high and unforeseen tolerance towards harsh environmental conditions. Such species could be utilized as AMF inocula specifically selected for their proven resilience in paved sites, in order to exploit their ability to boost biogeochemical processes fundamental for energy fluxes and plant nutrition and health.     

Field response of papaya (Carica papaya L. cv. Coorg Honey Dew) to inoculation with arbuscular mycorrhizal fungi at different levels of phosphorus

Summary

Papaya (Carica papaya L.) cv. Coorg Honey Dew is one of the most popular cultivars grown in Southern India, but it requires high doses of inorganic phosphorus (P) fertilisation for growth. Arbuscular mycorrhizal fungi (AMF) are known to improve plant growth and nutrient uptake, especially the uptake of P and micronutrients. As papaya plants respond well to high levels of P, inoculation with AMF was studied to see if AMF could fulfill the requirement for P in plants grown under field conditions. Papaya seedlings (n = 36 per AMF) were colonised separately, in polybags, for 45 d by two species of AMF, Glomus mosseae and G. fasciculatum. Seedlings were then transplanted to the field, with uninoculated seedlings as controls, in a replicated randomised block design. Three levels of P were applied [50, 75, or 100% of the recommended dose (240 g plant^–1 year^–1) of P fertiliser, as super-phosphate]. Plants were studied for root colonisation by AMF, for growth parameters, and for leaf nutrient contents (especially, P, Zn, and Cu). Acidic and alkaline phosphatase activities in the roots of AMF-colonised plants were recorded as these enzymes are involved in the mobilisation of P. The yields of plants up to 18 months-old, and fruit quality, measured by total soluble solids contents (TSSC) and β-carotene contents, were recorded. AMF-inoculated plants performed better than uninoculated control plants at all levels of P applied. G. mosseae was more effective at improving plant growth, fruit yield, and P and Zn contents than G. fasciculatum at the 75% and 50% P-levels. Cu contents increased at all P-levels in G. fasciculatum-colonised plants. Total soluble solids contents showed marginal improvements at the 75% P level with both fungi. β-carotene contents increased significantly in G. mosseae-colonised plants at the 50% and 75% P-levels, and in G. fasciculatum-colonised plants at the 75% P-level. The feasibility of applying on-farm produced AMF inoculum to improve papaya cultivation and to save 25% of the P applied during papaya cultivation is discussed.     

丛枝菌根真菌对水分胁迫下枇杷实生苗生长和养分吸收的影响

 以‘早钟6号’枇杷（Eriobotrya japonica Lindl.‘Zaozhong 6’）实生苗为试材,研究了3种水分梯度（正常供水、轻度水分胁迫和重度水分胁迫）下,分别接种3种丛枝菌根（arbuscular mycorrhiza,AM）真菌（光壁无梗囊霉Acaulospora laevis、摩西球囊霉Glomus mosseae和苏格兰球囊霉Glomus caledonium）对实生苗生长和养分吸收的影响。结果表明,接种AM真菌的植株具有更高的地上部和地下部干质量;3种AM真菌均可增加枇杷苗氮、钾、磷、钙、镁、铜的吸收。说明接种AM真菌增强了枇杷苗的养分吸收能力,提高了其抗旱性,促进了枇杷苗生长。在3种AM真菌中苏格兰球囊霉是枇杷苗的优势菌种。