云南会泽废弃铅锌矿区和非矿区中华山蓼根际真菌镉耐性研究

采用常规、含Cd2＋和含Pb2＋的马丁氏培养基,对云南省会泽县废弃铅锌矿区和非矿区中华山蓼（Oxyria sinensis Hemsle）根际真菌进行分离,将分离的菌株接种到含不同浓度（0、0.05、0.5和5mmol·L-1）Cd2＋的马铃薯葡萄糖培养液中,研究和比较了废弃铅锌矿区和非矿区中华山蓼根际真菌的镉耐性。结果表明,Cd2＋显著抑制铅锌矿区和非矿区中华山蓼根际真菌的生长;Cd2＋对常规、含Cd2＋和含Pb2＋的马丁氏培养基分离的铅锌矿区中华山蓼根际真菌的EC50平均值和最大值均明显大于非矿区,表明铅锌矿区中华山蓼根际真菌对Cd2＋的耐性强于非矿区,采用含Cd2＋培养基,从铅锌矿区中华山蓼根际分离出的真菌Cd2＋耐性最强。     

盐胁迫下AM真菌对紫花苜蓿生长及生理特征的影响

利用盆栽试验研究了NaCl胁迫条件下AM真菌对紫花苜蓿(Medicago sativa L.)植株生长及生理特征的影响。结果显示:随土中加入NaCl浓度增高(0%,0.5%,1.0%),与未接菌紫花苜蓿相比,接种AM真菌显著(P<0.05)促进紫花苜蓿生长,并使其可溶性糖、可溶性蛋白及根系脯氨酸累积量增加。1.0%NaCl接种AM真菌处理下根系鲜重(28.1 mg)为0%NaCl未接种下的1.27倍;不同盐处理接种AM真菌植株丙二醛含量均低于对照株;1.0%NaCl浓度下接种AM菌植株叶片及根系脯氨酸含量分别为对照株的0.82,1.41倍。表明AM真菌在胁迫环境下不仅可促进植株生长发育及渗透调节物质的积累,还可维持植物体丙二醛含量较低水平,降低植株遭受盐胁迫,推测叶片与根系脯氨酸对ABA依赖程度不同而导致其脯氨酸含量不同。     

Arbuscular mycorrhizal fungi in degraded typical steppe of inner Mongolia

Arbuscular mycorrhizal (AM) fungi may have some potential use in the restoration of degraded grassland through beneficial effects on plant growth and soil quality. A field investigation was conducted in three grassland sites of typical steppe in Inner Mongolia. The three plant communities, one of which was undegraded, one moderately degraded and the third severely degraded, were studied by collecting soil samples and samples of four plant species that occurred in all three sites. The percentage of root length colonized by AM fungi was estimated and the species composition and diversity of AM fungus spores recovered from the soil were determined using spore morphological characteristics. Although differences between the sites may have been due partly to other factors, it is likely that the degree of degradation was an important factor. No decline was found in the AM colonization of the roots of the indicator plant species in the moderately or severely degraded plant communities, and two plant species showed higher colonization status in the two degraded areas. Glomus geosporum and Scutellospora calospora were the dominant AM fungi in the undegraded steppe, while G. geosporum and Glomus aggregatum dominated the two degraded sites which also had low spore densities, species richness and diversity indices. However, different AM species showed different distributions among the three plant communities and the results indicate that both biotic and abiotic factors were important in determining the AMF communities, with biotic factors possibly the more important. Copyright © 2008 John Wiley & Sons, Ltd.     

食用菌栽培料堆制诱发灭菌新方法探讨

将栽培料大量堆制,并控制适宜堆湿、堆温、翻堆和时间,诱使料中杂菌由休眠的孢子体转变为营养生长体,降低杂菌细胞对高温的忍耐力,再行一次短时常压灭菌,把料内杂菌一次杀灭.这样将灭菌过程分为诱发与杀灭二个阶段,这就构成了一种新的栽培料灭菌法——堆制诱发灭菌法.用之于生产,是解决目前平菇发菌阶段杂菌污染行之有效的措施.     

Global diversity and distribution of arbuscular mycorrhizal fungi

Arbuscular mycorrhizal (AM) fungi form associations with most land plants and can control carbon, nitrogen, and phosphorus cycling between above- and belowground components of ecosystems. Current estimates of AM fungal distributions are mainly inferred from the individual distributions of plant biomes, and climatic factors. However, dispersal limitation, local environmental conditions,and interactions among AM fungal taxa may also determine local diversity and global distributions. We assessed the relative importance of these potential controls by collecting 14,961 DNA sequences from 111 published studies and testing for relationships between AM fungal community composition and geography, environment, and plant biomes. Our results indicated that the global species richness of AM fungi was up to six times higher than previously estimated, largely owing to high beta diversity among sampling sites. Geographic distance, soil temperature and moisture, and plant community type were each significantly related to AM fungal community structure, but explained only a small amount of the observed variance. AM fungal species also tended to be phylogenetically clustered within sites, further suggesting that habitat filtering or dispersal limitation is a driver of AM fungal community assembly. Therefore, predicted shifts in climate and plant species distributions under global change may alter AM fungal communities.     

接种丛枝菌根对复垦矿区玉米中重金属含量的影响

采用盆栽试验方法,研究了不同培养基质条件(10cm土5cm尾矿、8cm土7cm尾矿、5cm土10cm尾矿)下,接种丛枝菌根真菌和不接种菌根(对照)两种处理对玉米的生物量及植株对重金属元素吸收的影响。结果表明,无论接种与否,植株的生物量都随覆土厚度增大而增大;接种菌根处理中,植株地上部Cr、Cd、Pb等重金属元素的含量比对照处理均有明显降低。植株地上部Pb、Zn、Cu等元素的带走量,接种菌根处理的植株均比其相应的对照处理明显增多,而植株没有表现出受害症状,表明接种菌根可以显著提高玉米植株地上部对重金属的抵抗作用。接种菌根处理的植株中Cd、Cr、Pb、Zn的带走总量均高于对照处理,但因它们绝大部分结合在根部,向植株地上部分的转运受到抑制,而减轻了对人畜的危害。     

食用菌产业集群升级的路径与保障措施

食用菌产业具有生产集约化、作业标准化、产业绿色化的显著特点。目前,我国食用菌产业集群初步成型,但区域差异较大。虽然产品类型丰富,但技术水平偏低,且与美国相比,价值链的延伸还较为不够。因此,既要进一步推动产业补链、强链,加强科技创新赋能,打造特色产业品牌,形成共享协同机制,从而助推食用菌产业集群升级;又要强化产业政策引领,完善行业管理标准,重视优秀人才引育,从而夯实食用菌产业集群升级保障。     

梅花内生真菌及其多样性

通过采样、组织分离、培养与鉴定,对梅花内生真菌种类、分布及多样性进行了初步研究。结果表明:梅花内生真菌具有丰富的生物多样性,共得到梅花内生真菌15种。其中产孢真菌8属12种,非产孢真菌3种。它们多数为半知菌,少数为接合菌,曲霉1(Aspergillus sp.1)和青霉1(Penicillium sp.1)是梅花内生真菌优势种。梅花内生真菌广泛分布于各种组织内,总定殖率为54.8%,在嫩枝木质部定殖率最高,达65.6%。梅花植物体外部生态环境及内部组织类型对内生真菌的种类与分布均有重要影响。     

作物定位轮作体系长期试验研究(Ⅳ)——土壤优势真菌对大豆种子萌发的影响

试验于2000年在东北农业大学院内试验田进行,从大豆正茬、迎茬、连作、7年连作(自1994年连续种植大豆)田间土壤中分离出优势真菌进行实验.研究表明,土壤真菌优势类群在苗期以木霉、青霉、镰刀菌为主,在盛花期和结荚期以青霉、毛霉、黑根霉为主,连作大豆的土壤真菌优势类群的种类、数量高于其它茬口.经不同茬口土壤真菌毒素液处理大豆种子后,表现出抑制大豆种子发芽,各处理间由于品种不同、茬口不同略有差别,抑制作用为连作＞迎茬＞正茬,7年连作处理的抑制作用有强有弱.     

刺五加内生真菌对刺五加苷B和E含量的影响

[目的]分析内生真菌对刺五加中刺五加苷B,E含量的影响。[方法]以分离自不同产地的刺五加内生真菌为试材．以伤口法回接,HPLC法测定刺五加苷B、E含量。[结果]结果表明,25株内生真菌中有16株为致病菌,9株为非致病菌。其中来自产地吉林省梅河口市刺五加的菌株P116-1a、P109—4、P116-1b和P312—1均不同程度地提高了刺五加茎、根茎中刺五加苷B、E的含量。[结论]刺五加内生真菌可通过产生的代谢物调节刺五加苷B、E的含量。