赤松菌根化育苗技术的研究

以赤松外生茵根菌种为试材,对茵根化育苗生产技术进行了研究.结果表明:在常规培养基(PDA中)中以加入20%的麦麸汁培养基效果最好;松茸茵的最佳培养温度是25℃,最适pH值是5.5;经松茸液体茵剂处理的赤松种子的出苗率比对照提高了32%;赤松茵根化育苗技术的实施使赤松接种苗比对照在株高、地径、干重等方面都有极其显著的提高,3项指标分别提高44.85%、31.3%和33.3%.     

土生空团菌(Cenococcum geophilum Fr.)的菌种鉴定及其遗传多样性的初步分析

 【目的】鉴定外生菌根真菌土生空团菌（Cenococcum geophilum Fr.（Cg））菌种，分析土生空团菌的遗传多样性，探讨影响土生空团菌遗传分化的因素。【方法】采用形态特征结合PCR方法，从分离自6种寄主植物的27个中国菌株和来自法国的5个Cg菌株中鉴定出20个Cg菌株。利用PCR-限制性片段长度多态性（PCR-RFLP）和随机扩增片断多态性DNA（RAPD）两种分子标记方法对这20个Cg菌株进行遗传多样性分析。【结果】PCR-RFLP方法以通用引物ITS1和ITS4对20个Cg菌株的核糖体DNA转录间隔区（ITS）进行了PCR扩增，扩增产物用3种内切酶（EcoRⅠ、HinfⅠ和MboⅠ）酶切，酶切图谱显示菌株间有明显差异。RAPD方法用经过筛选的随机引物（5'-CGCACCGCAC-3'）对20个菌株的基因组DNA进行PCR扩增，扩增产物的片段大小在300～2 000 bp范围之间，共产生19个多态性位点。根据电泳图谱上DNA带的数目、位置及强度进行数值化，用聚类分析软件计算菌株间的遗传距离和遗传相似性，根据遗传距离构建20个菌株的系统聚类图。【结论】来源于不同寄主及地域的20株Cg有着较丰富的遗传多样性；地理环境和寄主对Cg遗传多样性的影响不大。     

板栗共生菌根真菌种类及其发生规律的研究

经调查能与板栗形成外生菌根的真菌有１３属２９种，分布的优势真菌有马勃属（ｌｙｃｏｐｅｒｄｏｎ）、须腹菌属（Ｒｈｉｚｏｐｏｇｏｎ）、秃马勃属（Ｃａｌｖａｔｉａ）、红菇属（Ｒｕｓｓｕｌａ）、牛肝菌属（Ｂｏｌｅｔｕｓ）、鹅膏属（Ａｍａｎｉｔａ）、松塔牛肝菌属（Ｓｔｒｏｂｉｌｏｍｙｃｅｓ）等。外生菌根真菌与板栗共生关系的强弱主要取决于真菌种类，马勃类和须腹菌与板栗共生菌根发育最好，其次为红菇属及牛肝菌属。不同真菌发生的规律不同，但子实体“潮”的出现与降雨最为密切。土壤通气性好、湿度较大有利于菌根真菌子实体发生，新开展育苗的苗圃地菌根种类不甚丰富。菌根的生长伴随着板栗新根的发生和生长。     

The impact of trees, ectomycorrhiza and potassium availability on simple organic compounds and dissolved organic carbon in soil

The presence of tree roots and symbiotic mycorrhizal fungi is recognized to have a substantial impact on carbon dynamics in soils. In this study the effect of Pinus sylvestris seedlings and the ectomycorrhizal fungus Hebeloma crustuliniforme on a number of biogeochemical variables, mainly related to labile carbon pools was investigated. The impact of K limitation as a potential regulatory factor was also examined. Columns filled with E horizon ±plants and ±mycorrhizal fungi were incubated for 18.5 months. The results demonstrate that plants, as well as mycorrhizal fungi, significantly increased the concentrations of some simple organic acids, including oxalate, in soil solution. Observations for dissolved organic carbon were slightly contradictory but the cumulative amount found in drainage water was ∼20% higher in planted versus non-planted columns. Soil from planted treatments also showed more rapid mineralisation kinetics for oxalate. However carbon utilization (mineralisation vs. biomass) of oxalate and glucose by the soil microbial biomass was less influenced by plants. At harvest a component integration study of soil autotrophic and heterotrophic respiration was performed which revealed that both plant and mycorrhiza had a positive effect on the heterotrophic respiration. Potassium omission had little effect on the variables studied with the exception of the maximum mineralisation rate for oxalate, which increased when K was withdrawn. The results are discussed in the context of the dynamics of labile soil carbon pools and ecosystem C fluxes.     

A new mycorrhizal helper bacterium, <Emphasis Type="Italic">Ralstonia</Emphasis> species,in the ectomycorrhizal symbiosis between <Emphasis Type="Italic">Pinus thunbergii</Emphasis> and <Emphasis Type="Italic">Suillus granulatus</Emphasis>

In a Robinia-pseudoacacia-dominated coastal forest in Tottori prefecture Japan, the growth and survival of Pinus thunbergii seedlings and the natural regeneration of P. thunbergii was disturbed by R. pseudoacacia. In order to improve the growth of P. thunbergii seedling in the Tottori sand dune, we tried to find a mycorrhiza helper bacteria (MHB) from P. thunbergii mycorrhizosphere in a Tottori sand dune. Two MHB, Ralstonia sp. and Bacillus subtilis, were selected from the nine bacterial species isolated from the mycorrhizosphere of P. thunbergii. The bacterial effect on the ectomycorrhizal fungus Suillus granulatus was investigated by confrontation assay and a microcosm experiment. The confrontation assay showed that Ralstonia sp. promoted the hyphal growth of S. granulatus. Moreover, the S. granulatus–P. thunbergii symbiosis was significantly stimulated by Ralstonia sp. and B. subtilis. Ralstonia sp. and B. subtilis were regarded as MHB associated with P. thunbergii. This is the first report of Ralstonia sp. as an MHB.     

钾对外生菌根真菌分泌氢离子及吸收氮磷钾的影响

利用无钾、低钾、中钾和高钾的液体培养基培养3种外生菌根真菌28d,研究了外生菌根真菌的生物量、氢离子的分泌状况以及真菌菌丝体内氮、磷、钾含量。结果表明,外生菌根真菌在中钾的条件下生长最好,无钾、低钾或高钾时生长受到抑制;在无钾和低钾时分泌氢离子的速率最高,有利于土壤中无效钾的活化;钾的供应水平对真菌体内氮、磷、钾的含量有不同程度地影响。     

铝胁迫下外生菌根真菌对土壤无机磷的溶解释放

[目的]研究铝胁迫下外生菌根真菌对土壤无机磷的溶解释放。[方法]铝胁迫下,以彩色豆马勃(Pisolithus tinctorius,编号Pt)和松乳菇(Lactarius delicious,编号Ld)为供试菌株,土壤为唯一磷源,采用液体培养试验研究菌丝生长情况,以及对土壤无机磷的活化。[结果]在铝胁迫下,2株外生菌根真菌的生物量随着铝离子浓度的升高,表现为先增高后降低的趋势,其中,在0~2.0 mmol/L铝离子浓度下,Pt的生物量均大于Ld,说明Pt的抗铝毒能力强于Ld。此外,p H在铝离子胁迫下显著下降,2株外生菌根真菌不同程度地活化土壤中无机磷。[结论]外生菌根真菌的抗铝和溶磷能力与其分泌的氢离子和有机酸有关。     

云南松菌根菌的分离培养条件筛选

在对云南松的外生菌根菌进行分离的基础上,得到生长较好的外生菌根菌株.用不同培养基、不同温度对分离出的菌株进行培养,测定其生长量,从中筛选出最适合外生菌根菌生长的培养基和温度.结果认为,3个菌株适合在马铃薯、MMN和PDA 3种培养基中生长,适合在27℃条件下生长.     

盆栽桧柏幼苗接种五种不同菌根真菌的比较研究

本文针对内蒙及三北地区主要园林绿化树种桧柏进行了盆栽菌根真菌接种试验。通过试验证实：兰丝膜菌（Ｃｏｔｉｎａｒｉｕｓｃａｅｒｕｌｅｓｃｅｎｓ）对桧柏幼苗生物生长量的促进作用十分明显：高生长量比对照提高５２％,生物量提高８８％;其它供试菌种各项测试指标均相对较差。由此初步认为兰丝膜菌为桧柏的一个优良共生菌根真菌。     

外生茵根在森林生态系统中的重要性(Ⅰ)--外生茵根对宿主树木的影响

文章根据国内外的菌根文献资料,综述了外生菌根形成对宿主树木的影响.外生菌根对宿主树木的主要作用包括:外生菌根能扩大树木根系的吸收面积和吸收范围,增强宿主树木对营养元素的吸收和利用,菌根菌还能通过合成植物激素来调节共生双方,菌根还能提高宿主树木的抗病性和抗逆性.