锌污染条件下VA菌根对三叶草生长和元素吸收的影响

采用三室隔网盆栽方法研究了3种不同施锌水平下，接种VA菌根菌（G.mosseae）对红三叶草植株生长和养分吸收的影响．结果表明，施锌水平对菌根侵染率无显著影响，说明供试菌种对锌的污染有较强的适应能力．菌根的浸染显著改善了植物的磷营养状况，使植株含磷量增加了1倍多，因此大大促进了植株的生长．菌根侵染对微量元素表现出不同的作用，与不接种的对照相比，菌根侵染植株体内Cu的含量增加，Fe的含量降低，而对Zn、Mn的影响不大．     

VA菌根真菌对玉米生长及根际土壤微生态环境的影响

用两种不同的VA菌根真菌Glomus mosseae和Glomuscaledonium接种玉米进行盆栽试验。结果表明,两种菌株均能侵染玉米,促进玉米生长．其中以Glomus caledonium的侵染率和作用较为明显。接种后,根区土壤中的细菌、放线菌、固氮菌的数量和微生物生物量明显增加,但真菌的数量则稍有下降。此外．菌根的形成也改善了根区土壤的微生态环境,为下一造作物的生长积累了养分基础。     

棉花VA菌根的形成与土壤几丁质酶活相关性的研究

盆栽条件下，对棉花ＶＡ菌根的形成与根区土壤中几丁质酶活的相关性及其动态变化的研究结果表明．接种ＶＡ菌根真菌Ｇｌｏｍｕｓｍｏｓｓｅａｅ形成的菌根可促进解几丁质微生物的增殖，并能诱导出较高的土壤几丁质酶活性．酶活增长与菌很感染率成正相关；接种ＶＡ菌根真菌的处理与未接种对照比较，差异显著或极显著．     

VA菌根对喀斯特草本群落植物根际养分影响研究

以贵州花江喀斯特高原生态综合治理试验示范区内草本群落阶段的几种主要植物为材料,对其根际微生态环境进行了研究,包括根际土壤化学性质、土壤酶活性和VA菌根侵染率及AMF孢子密度。结果表明：VA菌根侵染率和根际土壤中AMF孢子密度存在极显著正相关,相关系数达到0.97;不同植物根际土壤的化学指标和土壤酶活性均表现出较强的根际效应,即R/S〉1;VA菌根侵染率与pH值存在显著负相关,与有效磷质量分数存在极显著正相关,与碱性磷酸酶存在显著正相关,说明VA菌根能够促进土壤中难溶态磷往有效磷方向转化;AMF对宿主植物的侵染能够在一定程度上改善根际微生态环境的营养状况。     

泡囊丛枝菌根对红三叶草根际土壤磷酸酶活性的影响

以三叶草为材料,利用三室隔网培养方法,研究了缺磷土壤上施用植酸时接种３种泡囊丛枝菌根真菌（Ｇｌｏｍｕｓ ｍｏｓｓｅａｅ,Ｇｌｍｏｕｓ ｖｅｒｓｉｆｏｒｍｅ,Ｇｉｇａｓｐｏｒａ ｍａｒｇａｒｉｔａ）对根际土壤酸性磷酸酶和碱性磷酸酶活性的影响。三叶草生长６０ｄ后,收获测定距根表不同距离土壤中的磷酸酶活性,结果表明,接种菌根真菌增加了根际土壤酸性和碱性磷酸酶活性,Ｇｉｇａｓｐｏｒａ ｍａｒｇａｒｉｔａ菌     

VA菌根在柑桔上的应用及其前景

由于菌根在农业、林业生产中的重要性,对菌根的研究,尤其是对VA菌根的研究已引起人们广泛的重视.本文对VA菌根的研究及利用现状,尤其是VA菌根与植物营养,VA茵根与植物的抗性生理以及VA菌根、根瘤菌与植物三联体的效应等方面的动态作一综述,并对柑桔菌根今后的研究提出几点建议,其中包括菌根资源的调查、菌根资源圃的建立、柑桔菌根与环境、菌根与柑桔的抗性生理等。     

空气CO2体积分数升高对稻麦根系活力及其VA菌根侵染率的影响

利用无锡市安镇的FACE研究平台，在施常规氮量和低氮量的条件下，研究CO2体积分数升高对稻麦轮作系统水稻和小麦根系活力及其VA菌根侵染率的影响。结果表明，在常氮和低氮条件下，FACE处理对小麦和水稻根系活力都有促进作用，并使小麦VA菌根侵染率在拔节期和孕穗期有增加趋势，小麦根系活力和VA菌根侵染率有正相关关系。施N量不足对作物根系生长和活力有一定影响，可以被CO2体积分数升高的影响所补偿。     

不同磷效应基因型小麦对VAM真菌领事性的影响因子及机理

以高、中、低效３个磷效率基因型泪科为试材,在ｗ（Ｐ２Ｏ５）＝２０ｍｇ／ｋｇ和６０ｍｇ／ｋｇ的水平下,接种或不接种两个ＶＡ菌根真菌Ｇｌｏｍｕｓ ｍｏｓｓｅｃａ和Ｇｌｏｍｕｓ ｖｅｒｓｉｆｏｒｍｅ,研究了影响小麦菌根依赖性因子及机理。结果表明,在低磷水平下,小麦菌根依赖笥的大小顺序为中净重〉低效〉高效;对Ｇ．ｖｅｒｓｉｆｏｒｍ的依赖性大于对Ｇ．ｍｏｓｓｃａｅ和依赖性;而在高磷水平下,接种菌根表现出不同     

分子生物学技术在菌根研究中的应用及其进展

近几年来,菌根分子生物学得到了较快发展;尤其是一些用于首根真菌ITS区域的特异引物先后设计并合成成功,进一步推动了菌根学在分子水平上的研究。分子生物学技术在留根真菌分类鉴定及亲缘关系研究上应用较多。在菌根菌竟争性和持续性研究上．DNA分析技术已成为最重要的研究手段之一。在这些研究中,专为菌根真菌ITS区域分析而设计的ITS1-F和ITS4-B两种特异引物应用最为普遍。本文对菌根DNA分析技术、PCR－RFLP技术做了简单介绍;综述了PCR、ITh－RFLP等分析技术在菌根菌分类、亲缘关系及菌种持续性等方面的研究和应用情况。     

不同磷效率基因型小麦对VAM真菌依赖性的影响因子及机理

以高、中、低效３ 个磷效率基因型小麦为试材,在ｗ（Ｐ２Ｏ５） ＝２０ ｍｇｋｇ 和６０ ｍｇｋｇ 的水平下,接种或不接种两个ＶＡ菌根真菌Ｇｌｏｍｕｓ ｍｏｓｓｅａｅ 和Ｇｌｏｍｕｓｖｅｒｓｉｆｏｒｍｅ,研究了影响小麦菌根依赖性的因子及机理．结果表明,在低磷水平下,小麦菌根依赖性的大小顺序为中效＞ 低效＞ 高效;对Ｇ． ｖｅｒｓｉｆｏｒｍ 的依赖性大于对Ｇ． ｍｏｓｓｅａｅ 的依赖性;而在高磷水平下,接种菌根表现出不同程度的生长抑制作用．相关分析发现,菌根依赖性与根冠比、根长、根毛长度、根毛密度、磷利用效率之间的相关性不显著;在低磷水平下,菌根依赖性与磷效率、根吸收效率之间呈极显著的负相关,与韧皮部蔗糖运输速率之间呈显著或极显著的正相关．认为影响不同磷效率基因型小麦菌根依赖性的主要因子是根的吸收效率;菌根依赖性、磷效率和韧皮部蔗糖运输速率均受根吸收效率影响     

VA菌根菌与植物的抗病性

VA菌根菌（VAM菌）与植物土传病害的关系受到广泛的研究。本文从VAM菌对植物抗病性的影响及其可能性机理和相应的农业管理措施等方面进行了介绍和评述,同时提出问题和展望,并强调该方面的研究在可持续发展农业中的重要性。     

Studies of VA-Mycorrhizal fungi associated with some weed plants in sugar mill effluent soils

This study is to isolate the effluent strain of VAM fungi from polluted soils of sugar mill effluents. Analysis showed that pH and EC was more but the organic matter is less when compared to non-polluted soils. Even though there was low P content that enhances the mycorrhizal infection, the percent of root colonization was less than 75% in polluted study site. The number of VAM propagules and its distribution were also greatly affected due to various factors. Nine different VAM species were isolated and identified from the polluted study site. Using Allium cepa L. as the host plant the efficiency of the native effluent tolerant strains of VAM fungi isolated from the polluted study site was determined. Highest growth rate, high dry weight of gram per plant and increased growth was observed in the order of Glomus intraradices followed by Gigaspora margarita and Glomus fasciculatum. Consequence of the study clearly showed that Glomus intraradices was the efficient strain in sugar mill effluent polluted areas.     

Infectivity and efficacy of Glomus aggregatum and growth response of Cajanus cajan (L.) Millsp. in flyash amended sterile soil

In the present investigation a pot culture experiment was conducted using sterile, phosphorus deficient soil to study the effect of flyash at 3 different concentrations (10g, 20g and 30g flyash/kg soil) on the infectivity and effectiveness of VAM fungus Glomus aggregatum in pigeonpea (Cajanus cajan (L.) Millsp.) cv Maruti. The flyash amendment in soil at all the 3 different concentrations was found to affect significantly the intensity of VAM fungal colonization inside the plant roots and also suppressed the formation of VAM fungal structure (vesicles and arbuscules) completely at higher concentration (30g flyash/kg soil). The response of the pigeonpea plants, as judged by their higher and dry weight, under the influence of flyash amendment in VAM fungus infested soils was found to be considerably less (though not significant enough) when compared to the control plants (without flyash) that have otherwise shown significant increase in growth over the plants without Glomus aggregatum inoculation. However, flyash amendment without VAM inoculation was also found to enhance the growth of plants as compared to control plants (without flyash and VAM inoculum).     

Effects of vesicular-arbuscular mycorrhizal (VAM) fungi on the seedling growth of three Pistacia species

The experiment was undertaken to test the efficiency of inoculation of vesicular-arbuscular mycorrhizal (VAM) fungi on the seedling growth of three Pistacia species used as rootstocks. The stratified Pistacia seeds were inoculated with VAM fungi. The highest rate of inoculated roots was 96.7% in P. khinjuck seedlings with G. clarum and G. etunicatum, 83.3% in P. vera seedlings with G. caledonium and 73.3% in P. terebinthus seedlings with G. caledonium. Mycorrhizal inoculations improved seedling height only in P. terebinthus. Certain mycorrhizal inoculations increased the leaf N, but not P and K contents. Seedlings inoculated with G. caledonium had higher reducing sugar contents. It was concluded that pre-inoculated Pistacia seedlings could have a better growth in the harsh field conditions.     

Evidence for ecological matching of whole AM fungal communities to the local plant-soil environment

The range of ecological roles exhibited by arbuscular mycorrhizal (AM) fungi depends on functional differences among naturally occurring local assemblages of AM species. While functional differences have been demonstrated among AM fungal species and among geographic isolates of the same species, almost nothing is known about functional differences among whole communities of naturally occurring AM fungi. In the greenhouse, we reciprocally transplanted whole AM fungal communities between plant-soil systems representing a serpentine grassland and a tallgrass prairie, using as hosts two grasses common to both systems. For Sorghastrum nutans, native fungi consistently enhanced plant growth more than fungi switched from the alternate system. For Schizachyrium scoparium, foreign and native fungi promoted plant growth similarly in both the serpentine and prairie systems. Thus, the use of foreign inoculum in restoration could change the relative performance, and potentially the competitive abilities, of co-occurring plant species. Moving AM fungal inocula into foreign environments also caused changes in the taxonomic composition of the resultant spore communities, demonstrating their response to environmental influences. These results provide strong evidence for functional differences among naturally occurring AM communities and suggest that a particular AM fungal community may be better matched ecologically to its local habitat than communities taken from other locations.     

接种Glomus versiforme对红三叶草利用有机磷的影响

以红三叶草为材料,利用三室隔网培养方法,研究接种菌根真菌Glmous versiforme对土壤有机磷及外加有机磷化合物植酸钠（Na-Phytate)、核糖核酸（RNA）和卵磷脂（Lecithin)的利用效率,植株生长7wk后收获测定植标干物重、含磷量和根系菌根侵染率,结果表明：接种菌根真菌能明显增加植株干物重、含磷量和吸磷总量,与各有机磷处理相比,无机磷（KH2PO4）处理生长效应最好,施用有机磷化合物各处理与CK相比均明显促进了植株生长,但不同有机磷处理之间没有显著差异,在植株吸磷量上,各接种处理均为相应CK处理的2倍以上,其中磷酸二氢钾处理吸磷量最高,菌根对照植物的根外菌丝虽然被限制在有限的空间内,但其吸磷量也达到不施磷的CK－M处理的2倍多,这说明由于菌根的形成植物能利用土壤因有的有机磷来满足自身生长的需要,表3参10     

Effects of sand movement by wind on nematodes and soil-borne fungi in coastal foredunes

In stabilized dunesAmmophila arenaria (marram grass) degenerates due to a process involving soil-borne pathogens and parasites. This leads to exposure of the sand surface so that wind erosion may create blowouts.Ammophila rejuvenates on the edges of the blowouts, where the sand has accumulated. We tested the hypothesis that such rejuvenation of plants may be related to a reduction of the plant-parasitic nematodes and fungal propagules during the process of wind-driven transport. Field measurements in blowouts during storm events indicated that the drifted sand contained relatively low numbers of plant pathogenic fungi and plant-parasitic nematodes. A wind tunnel experiment showed that drifting sand may indeed reduce the numbers of fungi and nematodes. Although most fungi were attached to sand particles, they were also affected by the wind-borne sand movement. Sand that had been deposited by wind was made up of a larger proportion of large-sized particles. In our experiment the relatively small particles were lost during transport. Stirring the soil (part of the forces of natural winds) by mixing for 15 min. with a propeller mixer at 1500 rpm significantly reduced the number of nematodes and fungi. Both sand movement in the wind tunnel and intensive stirring of the sand enhanced the growth ofAmmophila test plants in a bioassay. It was concluded that in wind-blown sand the pathogen inoculum is reduced. Therefore, serious consideration should be given to allowing controlled reactivation of blowouts to rejuvenate decliningAmmophila in stabilized foredunes. Implications for dune management are briefly discussed. Nomenclature: van der Meijden (1990) for vascular plants. Nematodes were identified to the genus level according to Bongers (1988). The allocation of nematodes to feeding groups was according to Yeates et al. (1993). Nomenclature of fungi according to Domsch et al. (1980) was used throughout this study except forFusarium. Species of the latter genus were identified according to Nelson et al. (1983).