On farm production of arbuscular mycorrhizal fungi inoculum using lignocellulosic agrowastes

The present study evaluated the efficiency of lignocellulosic agrowastes produced in Brazil as substrates for production of on farm AMF inoculum and tested different diluents and inoculation techniques. In a first experiment, Sorghum bicolor seedlings were colonized with Rhizophagus clarus or Claroideoglomus etunicatus and transplanted to 20 L bags containing sugarcane bagasse (SC), king palm leaf sheets (KP), or barley hulls (BH) mixed (1:1:1 or 2:1:1, v/v/v) with sand and rice shell. SC and KP were conducive for production of spores and infectious propagules. A number of infectious propagules obtained were greater than with BH and ranged from 233–350 propagules cm^?3 for both isolates in SC and KP at the1:1:1 mix dilution. Number of spores of both fungi was affected mainly by the SC agrowaste, and spore densities were significantly higher compared to KP and BH. In a second experiment, SC was mixed with soil or sand and inoculation consisted of transplanting colonized seedlings or adding soil inoculum. Number of propagules tended to differ for each fungus according to the inoculation technique or diluent. It is concluded from the data that SC and KP are suitable agrowastes to be incorporated in substrates for producing AMF inoculum using the on farm method.     

Effect of different organic manures/composts on the herbage and essential oil yield of Cymbopogon winterianus and their influence on the native AM population in a marginal alfisol

Four organic amendments: leaf compost (LC), vegetable compost (VC), poultry manure (PM) and sewage sludge (SSL) applied at four doses (40, 80, 100 and 120 tha(-1)) were evaluated for their effect on the herbage yield, essential oil content and inoculum potential (IP) of native arbuscular mycorrhizal fungi (AMF) on three varieties of Java citronella, Cymbopogon winterianus Jowitt (Manjusha, Mandakini, and Bio-13). PM applied at 100 t ha(-1) followed by SSL increased the herbage, essential oil content and dry matter yield significantly. Bio-13 performed better and produced the highest herbage, essential oil and dry matter yield. The type and dose of the various organic amendments also significantly influenced the indigenous AMF infectious propagules in soil. Highest number of AMF propagules were recorded in the LC amended plots in all the three varieties. Amongst the varieties, highest native mycorrhizal inoculum was recorded in the Bio-13. Least number of AM infectious propagules were recorded in the Mandakini plants grown in 40 t ha(-1) SSL.     

An arbuscular mycorrhizal inoculum enhances root proliferation in, but not nitrogen capture from, nutrient-rich patches in soil

Most work on root proliferation to a localized nutrient supply has ignored the possible role of mycorrhizal fungi, despite their key role in nutrient acquisition. Interactions between roots of Plantago lanceolata , an added arbuscular mycorrhiza (AM) inoculum and nitrogen capture from an organic patch ( Lolium perenne shoot material) dual-labelled with ¹⁵N and ¹³C were investigated, to determine whether root proliferation and nitrogen (N) capture was affected by the presence of AM fungi. Decomposition of the organic patch in the presence and absence of roots peaked in all treatments at day 3, as shown by the amounts of ¹³CO₂ detected in the soil atmosphere. Plant N concentrations were higher in the treatments with added inoculum 10 d after patch addition, but thereafter did not differ among treatments. Plant phosphorus concentrations at the end of the experiment were depressed by the addition of the organic residue in the absence of mycorrhizal inoculum. Although uninoculated plants were also colonized by mycorrhizal fungi, colonization was enhanced at all times by the added inoculum. Addition of the AM inoculum increased root production, observed in situ by the use of minirhizotron tubes, most pronouncedly within the organic patch zone. Patch N capture by the end of the experiment was c . 7.5% and was not significantly different as a result of adding an AM inoculum. Furthermore, no ¹³C enrichments were detected in the plant material in any of the treatments showing that intact organic compounds were not taken up. Thus, although the added AM fungal inoculum benefited P. lanceolata seedlings in terms of P concentrations of tissues it did not increase total N capture or affect the form in which N was captured by P. lanceolata roots.     

Field responses to added organic matter, arbuscular mycorrhizal fungi, and fertilizer in reclamation of taconite iron ore tailing

A three season study was conducted to determine the effect of added composted yard waste, arbuscular mycorrhizal (AM) fungi, and fertilizer on plant cover, standing crop biomass, species composition, AM fungal infectivity and spore density in coarse taconite iron ore tailing plots seeded with a mixture of native prairie grasses. Plant cover and biomass, percent seeded species, mycorrhizal infectivity and spore density were greatly increased by additions of composted yard waste. After three seasons, total plant cover was also greater in plots with added fertilizer. Third season plant cover was also greater in plots amended with the higher rate (44.8 Mg ha^{–1) of compost than the moderate rate (22.4 Mg ha-1}). Field inoculation with AM fungi also increased plant cover during the second season and infectivity during the first two seasons. Seeded native species, consisting mostly of the cover species Elymus canadensis, dominated plot vegetation during the second and third seasons. Dispersal of AM fungal propagules into nonmycorrhizal plots occurred rapidly and increased infectivity in compost-amended plots during the third season. In plots with less than 10% plant cover, AM fungal infectivity of inoculated plots was greatly reduced after the second season. The high level of plant cover and the trend of increasing proportion of mycorrhizal-dependent warm-season grasses, along with increases in infectivity, forecast the establishment of a sustainable native grass community that will meet reclamation goals.     

Characterization of fresh yard trimmings for agricultural use

Direct application of yard trimmings to agricultural land can benefit soils and crop production, while providing an outlet for handling high volumes of materials at compost facilities. Variability in the composition of yard trimmings can make it difficult to determine appropriate application rates. Our objective was to characterize the chemical composition and variability of yard trimmings generated throughout the spring and summer season at facilities in the Puget Sound region of Washington State. Yard trimmings were sampled from four composting facilities on five dates between April and August 1999. One material contained mostly grass clippings and had higher mean total N (3.2%) than mixed grass and woody materials (1.5-2%). Mean C:N was lower in the grass-rich material (12:1 vs. 15 to 21:1), while mean ammonium concentrations were similar (0.18-0.28%). Variation among facilities was greater than variation over time. The amount of variation observed with other nutrients, pH, EC, or trace elements would not affect use of the yard trimmings in agriculture. Our results suggest that it is possible to characterize yard trimmings adequately for agricultural use.     

The role of arbuscular mycorrhizal fungi in plant community establishment at Samphire Hoe, Kent, UK – the reclamation platform created during the building of the Channel tunnel between France and UK

Samphire Hoe is a newly-created land platform comprising the sub-seabed material excavated during the construction of the Channel tunnel. It represents a unique resource where the arrival and establishment of arbuscular mycorrhizal fungi (AMF) within a sown plant community on a low nutrient substrate can be monitored. Arbuscular mycorrhizal fungi invasion was monitored in a number of ways: by assessing the degree of root colonisation within the roots of plants on the site, by using a successive trap culture technique to determine AMF species richness, and by using sterile substrate bins to determine the extent of wind-borne and rain-dispersed immigration of AMF propagules into the site. Levels of colonisation of indigenous plants by AMF were high in May–June (the pre-flowering phase of growth for many plants) reflecting the important role of the mycorrhizal symbiosis in dry, low nutrient soils. Twelve species of AMF were identified, representing a relatively high diversity for a recently deposited subsoil. An on-site experiment indicated that inoculum of AMF could enter the site within 8 months and that wind dispersal and/or rain were possible vectors. A field experiment compared the outplanting performance of commercially-produced Elymus pycnanthus seedlings (in a commercial compost with added nutrients) with seedlings produced in a low nutrient substrate and inoculated with AMF isolated from the site (a mixture of 5 species of Glomus) or left uninoculated. After 14 months in the field seedlings, inoculated with the indigenous AMF, had the same tiller production as commercially-produced plants, despite slower initial growth. In contrast, non-mycorrhizal controls grew very poorly with a greater frequency of plant mortality compared with the other treatments. Elymus seedlings inoculated with the indigenous AMF ultimately produced approximately seven times the mean number of seed spikes per surviving plant as commercially-produced seedlings and five times greater weight of seed spike. A phyto-microbial approach to the revegetation of nutrient-poor soils is proposed to stimulate plant successional processes as a economically-viable sustainable input for landscaping anthropogenic sites.     

Improved aeroponic culture of inocula of arbuscular mycorrhizal fungi

We compared conventional atomizing disc aeroponic technology with the latest ultrasonic nebulizer technology for production of Glomus intraradices inocula. The piezo ceramic element technology used in the ultrasonic nebulizer employs high-frequency sound to nebulize nutrient solution into microdroplets 1 μm in diameter. Growth of pre-colonized arbuscular mycorrhizal (AM) roots of Sudan grass was achieved in both chambers used but both root growth and mycorrhization were significantly faster and more extensive in the ultrasonic nebulizer system than in the atomizing disc system. Shearing of the AM fungi (AMF) infected roots in both the systems did not reduce inoculum viability, as evident from the MPN data. However, sheared roots from the ultrasonic nebulizer system had significantly more infective propagules than those produced in the atomizing disc system. Thus, the latest ultra-sonic nebulizer aeroponic technology appears to be superior and an alternative to conventional atomizing disc or spray nozzle systems for the production of high-quality AMF inocula. These can be used in small doses to produce a large response, which is a prerequisite for commercialization of AMF technology. Accepted: 11 January 2000     

菌根真菌与施肥对杜鹃苗养分吸收的影响

以2年生杜鹃(Rhododendron simsii)苗为研究对象,采用J1(杜鹃花类菌根真菌混合接菌)、J2(杜鹃花类菌根真菌和马尾松外生菌混合接菌)、J3(不接菌,对照)等3种接菌组合与不同氮磷钾施肥组合研究菌根真菌与氮磷钾肥对杜鹃苗生长及养分吸收的影响。结果表明,杜鹃幼苗的生长指标和氮磷钾含量总体表现为接菌处理优于不接菌处理,J2处理下施用尿素1.1 g·株-1、钙镁磷1 g·株-1、氯化钾0.7 g·株-1对杜鹃苗生长及氮磷钾含量积累的促进作用最为明显。数据表明,J2处理促进N向叶积累,促进K向茎叶积累,促进P向根茎积累;J1处理促进N和P向根茎积累,促进K向茎叶积累。     

Mycorrhizal colonization of Pinus muricata from resistant propagules after a stand-replacing wildfire

Colonization of mycorrhizal fungi was studied in a Pinus muricata forest on the coast in California, USA, burned by a stand-replacing wildfire in October 1995. Naturally established field seedlings of P. muricata were harvested 1 yr after the fire. The species composition of the mycorrhizal fungi on these field seedlings was dominated by Rhizopogon species, Wilcoxina mikolae and Tomentella sublilacina . Bioassays, set up with soil collected immediately after the fire, were used to determine which mycorrhizal species had colonized the burned area from resistant propagules. The P. muricata seedlings in these bioassays were dominated by suilloid and ascomycetous fungi, the same fungi which dominated the mycorrhizal flora of seedlings in pre-fire bioassays derived from the same forest site, suggesting that resistant propagules were the primary inoculum source for naturally establishing seedlings. Drying of post-fire soil for 1 month raised the number of bioassay seedlings associated with Rhizopogon olivaceotinctus , while the number of bioassay seedlings associated with Rhizopogon ochraceorubens was reduced. Fire appeared to have either stimulated or provided a competitive advantage to R. olivaceotinctus , which increased in abundance on the post-fire bioassay and field seedlings. Soil collected from the burned area was diluted with sterile soil in three different concentrations, and the number and frequency of mycorrhizal taxa on bioassay seedlings decreased with increased dilution. Although precise quantification was not possible, propagules of the Rhizopogon species were much more abundant than those of Tomentella or Wilcoxina species. Differences between the mycorrhizal associates of bioassay seedlings, naturally regenerated seedlings, and different inoculum sources are discussed.     

丛枝菌根真菌应用技术研究进展

丛枝菌根(AM)共生体系能够改善植物营养状况,增强植物对各种逆境胁迫的耐受性,其在农业和生态环境方面的应用得到广泛关注.近年来,在AM真菌(AMF)应用技术和田间试验方面取得了许多重要成果.本文在介绍AMF种质资源库、商业化菌剂生产及相关专利申报情况的基础上,结合实例从菌剂生产、接种技术、接种效应影响因素等方面综述了AMF应用技术的理论与实践,包括国内外近年来菌根技术在农业、园艺、生态修复等方面的应用,最后提出尚待系统深入研究的 AMF应用领域中的关键科学和技术问题,旨在为菌根技术的发展和推广应用提供参考.     

Effect of arbuscular mycorrhizal colonization and two levels of compost supply on nutrient uptake and flowering of pelargonium plants

Two challenges frequently encountered in the production of ornamental plants in organic horticulture are: (1) the rate of mineralization of phosphorus (P) and nitrogen (N) from organic fertilizers can be too slow to meet the high nutrient demand of young plants, and (2) the exclusive use of peat as a substrate for pot-based plant culture is discouraged in organic production systems. In this situation, the use of beneficial soil microorganisms in combination with high quality compost substrates can contribute to adequate plant growth and flower development. In this study, we examined possible alternatives to highly soluble fertilizers and pure peat substrates using pelargonium (Pelargonium peltatum L’Her.) as a test plant. Plants were grown on a peat-based substrate with two rates of compost addition and with and without arbuscular mycorrhizal (AM) fungi. Inoculation with three different commercial AM inocula resulted in colonization rates of up to 36% of the total root length, whereas non-inoculated plants remained free of root colonization. Increasing the rate of compost addition increased shoot dry weight and shoot nutrient concentrations, but the supply of compost did not always completely meet plant nutrient demand. Mycorrhizal colonization increased the number of buds and flowers, as well as shoot P and potassium (K) concentrations, but did not significantly affect shoot dry matter or shoot N concentration. We conclude that addition of compost in combination with mycorrhizal inoculation can improve nutrient status and flower development of plants grown on peat-based substrates.     

Improvement of Cupressus atlantica Gaussen growth by inoculation with native arbuscular mycorrhizal fungi

AIMS: The study aimed to determine whether inoculation with native arbuscular mycorrhizal (AM) fungi could improve survival and growth of seedlings in degraded soils of Morocco. METHODS AND RESULTS: Soil samples were collected from the rhizosphere of Cupressus atlantica trees in the N'Fis valley (Haut Atlas, Morocco). AM spores were extracted from the soil, identified and this mixture of native AM fungi was propagated on maize for 12 weeks on a sterilized soil to enrich the fungal inoculum. Then C. atlantica seedlings were inoculated with and without (control) mycorrhizal maize roots, cultured in glasshouse conditions and further, transplanted into the field. The experiment was a randomized block design with one factor and three replication blocks. The results showed that a high AM fungal diversity was associated with C. atlantica; native AM fungi inoculation was very effective on the growth of C. atlantica seedlings in glasshouse conditions and this plant growth stimulation was maintained for 1 year after outplanting. CONCLUSIONS: Inoculation of C. atlantica with AM fungi increased growth and survival in greenhouse and field. SIGNIFICANCE AND IMPACT OF THE STUDY: The data indicate that use of native species of AM fungi may accelerate reforestation of degraded soils. Further studies have to be performed to determine the persistence of these mycorrhizae for a longer period of plantation and to measure the effects of this microbial inoculation on soil biofunctioning.     

Inoculation with arbuscular mycorrhizal fungi: the status quo in Japan and the future prospects

Inoculation of arbuscular mycorrhizal (AM) fungi has potential benefits in not only sustainable crop production but also environmental conservation. However, the difficulty of inoculum production due to the obligate biotrophic nature of AM fungi has been the biggest obstacle to putting inoculation into practice. Nevertheless, several companies have sought to produce inoculum of AM fungi. Firstly in this review, the present status of inoculum production and its use in Japan is described. Secondly, although the effectiveness of inoculation is primarily limited by environmental and biological factors, some possible ways to improve inoculation performance are discussed. Approaches include use of chemicals to increase spore germination and colonization and soil application of charcoal to provide a microhabitat for AM fungi to colonize and survive.     

分室培养装置在丛枝菌根真菌研究中的应用及其发展

重点围绕玻璃珠分室培养系统、H形分室培养系统、根排斥室培养系统、供体自养植物的双分室体外培养系统、丛枝菌根(AM)真菌与普通植物根器官的双重培养系统、AM真菌与Ri T-DNA转型根的双重单胞无菌培养系统、AM真菌与Ri T-DNA转型根双重培养的改良分室单胞培养系统等7个不同的分室培养装置, 对AM真菌的培养类型及其应用进行了系统的评述。其中, 采用玻璃珠分室培养装置易于将AM真菌与培养基质分开, 能获得大量纯净的AM真菌繁殖体, 用于研究AM真菌对矿质元素和微量元素的吸收, 具有不可替代的作用。H形分室培养系统和根排斥室(RECs)培养系统均能够获得连续的、可切断的共生菌根网络(CMNs), 可用于研究植物-植物、植物-昆虫之间化感作用产生的信息交流。供体自养植物的双分室培养系统有益于研究AM真菌对宿主植物在单作和混作条件下生长效应的影响。AM真菌与植物根器官的双重培养系统为研究AM真菌的侵染过程及生理、生化特性提供了极大的方便, 同时为纯培养研究提供了重要的理论依据。AM真菌与Ri T-DNA转型根的双重单胞无菌培养体系可以获得AM真菌纯净菌体, 是研究AM真菌遗传、生理、生化等特性的理想方法。以AM真菌与Ri T-DNA转型根的双重单胞无菌培养系统为基础, 可以在菌丝生长室置换培养基、在根室中补充适量碳源, 并多次收获AM真菌繁殖体。转型根改良双重培养系统是提高AM真菌孢子接种剂产量的有效方法。综上所述, AM真菌的分室培养系统已经取得显著进展, 为开展个体、种群、群落等不同层次的菌根生态学研究提供了依据。     

Evidence for mutualist limitation: the impacts of conspecific density on the mycorrhizal inoculum potential of woodland soils

The ability of seedlings to establish can depend on the availability of appropriate mycorrhizal fungal inoculum. The possibility that mycorrhizal mutualists limit the distribution of seedlings may depend on the prevalence of the plant hosts that form the same type of mycorrhizal association as the target seedling species and thus provide inoculum. We tested this hypothesis by measuring ectomycorrhizal (EM) fine root distribution and conducting an EM inoculum potential bioassay along a gradient of EM host density in a pinyon–juniper woodland where pinyon is the only EM fungal host while juniper and other plant species are hosts for arbuscular mycorrhizal (AM) fungi. We found that pinyon fine roots were significantly less abundant than juniper roots both in areas dominated aboveground by juniper and in areas where pinyon and juniper were co-dominant. Pinyon seedlings establishing in pinyon–juniper zones are thus more likely to encounter AM than EM fungi. Our bioassay confirmed this result. Pinyon seedlings were six times less likely to be colonized by EM fungi when grown in soil from juniper-dominated zones than in soil from either pinyon–juniper or pinyon zones. Levels of EM colonization were also reduced in seedlings grown in juniper-zone soil. Preliminary analyses indicate that EM community composition varied among sites. These results are important because recent droughts have caused massive mortality of mature pinyons resulting in a shift towards juniper-dominated stands. Lack of EM inoculum in these stands could reduce the ability of pinyon seedlings to re-colonize sites of high pinyon mortality, leading to long-term vegetation shifts.     

A new method of propagation of arbuscular mycorrhizal fungi in field cropped sesame (<Emphasis Type="Italic">Sesamum indicum</Emphasis> L.)

Though arbuscular mycorrhizal (AM) fungi are indigenous to agricultural soils, their beneficial effects to host plants could be further improved by inoculation with efficient species. The method of AM propagation described in the present study uses oil cake as a supporting medium for the simultaneous delivery of sesame seeds and AM inoculum to the field. Experiment was conducted in a farmer’s field located at Avoor, Kerala, India where sesame was cultivated as a winter crop in rice fallows. Oil cake entrapped with sesame seeds (var. Tilatara) and AM fungus (Funneliformis dimorphicus) inoculum was prepared by thoroughly mixing sterilized coconut cake and neem cake (5:1 v/v), surface sterilized sesame seeds and sterilized spore sieving of F. dimorphicus from a pot culture in a 10% solution of a polysaccharide gum obtained from the seeds of Strychnos potatorum L. Entire mix was moulded into 2.5 cm cubes (ca. 5g) containing approximately 25–30 seeds and 200–300 spores cube^?1 and shade dried before application. The cubes were broadcast @ 600 kg ha^?1 in inoculated treatments. In uninoculated treatments, the oil cake cubes devoid of the fungal component was used. Harvested root samples from the inoculated treatments showed a high frequency (%F) and intensity (%M) of colonization by AM fungi as well as frequency of vesicles (%V) and arbuscules (%A) compared to uninoculated control. The growth (root length, shoot length and leaf area) and yield characters (pod number, seed number, seed weight and oil content) of sesame plants were significantly (p=0.05) improved under the present method of AM propagation indicating its viability under field condition.     

Mycorrhizas in the Kakadu region of tropical Australia

This research represents the first part of a study which aimed to characterize the role of mycorrhizal associations in undisturbed and disturbed habitats in the Alligator Rivers Region of the Northern Territory of Australia. This is a seasonally dry tropical region with a climate consisting of a long dry season and a monsoonal wet season. Intact soil cores were sampled from 22 sites in this region, representing eucalypt savanna woodland, wetland, rocky hill and rainforest habitats. Clover, sorghum and eucalypt seedlings were grown in these cores in bioassays to measure the inoculum potential of vesicular-arbuscular mycorrhizal (VAM) and ectomycorrhizal (ECM) fungi. Propagules of VAM fungi were concentrated in the surface horizon, and were not adversely affected by 6 months dry storage of soil. Bioassays detected VAM fungus propagules at all sites, but these were less numerous in three sites with sparse herbaceous vegetation (a shrub-dominated woodland site, a sandstone area and a disturbed gravel pit without topsoil), than in other woodland sites. Propagules of VAM fungi were particularly numerous in soil from a rainforest habitat, which had much denser plant cover than any of the savanna sites. Propagules of ECM fungi colonized eucalypt seedling roots in some cores from all sites, except two wetland areas and a disturbed area without eucalypt trees. Physical and chemical properties of soils varied between sites and some properties (texture, organic carbon, etc.) were correlated with the inoculum potential of VAM fungi.     

Improving biocontrol of black vine weevil (<Emphasis Type="Italic">Otiorhynchus sulcatus</Emphasis>) with entomopathogenic fungi in growing media by incorporating spent mushroom compost

Amending a peat-based growing medium with 10% v/v spent mushroom compost, a source of fungal chitin and other nutrients, prolonged the persistence of entomopathogenic fungi (Metarhizium brunneum Petsch and Beauveria bassiana (Balsamo) Vuillemin; Hypocreales: Clavicipitaceae). This resulted in improved efficacy of M. brunneum against black vine weevil, Otiorhynchus sulcatus F. (Coleoptera: Curculionidae) larvae compared with using inoculum without spent mushroom compost. B. bassiana only controlled larvae when used in combination with spent mushroom compost (75?±?7% reduction in live larvae). Mixing entomopathogenic fungal inoculum with spent mushroom compost and growing medium was as effective in controlling black vine weevil larvae as using spent mushroom compost colonised with M. brunneum or B. bassiana in the growing medium (80?±?12% reduction in live larvae). The former method is preferable since it does not require production and storage of colonised spent mushroom compost, or registration of new substrate formulations of M. brunneum or B. bassiana.     

Availability and function of arbuscular mycorrhizal and ectomycorrhizal fungi during revegetation of dewatered reservoirs left after dam removal

Revegetation following dam removal projects may depend on recovery of arbuscular mycorrhizal (AM) and ectomycorrhizal (EM) fungal communities, which perform valuable ecosystem functions. This study assessed the availability and function of AM and EM fungi for plants colonizing dewatered reservoirs following a dam removal project on the Elwha River, Olympic Peninsula, Washington, United States. Availability was assessed via AM fungal spore density in soils and EM root tip colonization of Salix sitchensis (Sitka willow) in an observational field study. The effect of mycorrhizal fungi from 4 sources (reservoir soils, commercial inoculum, and 2 mature plant community soils) on growth and nutrient status of S. sitchensis was quantified in a greenhouse study. AM fungal spores and EM root tips were present in all field samples. In the greenhouse, plants receiving reservoir soil inoculum had only incipient mantle formation, while plants receiving inoculum from mature plant communities had fully formed EM root tips. EM formation corresponded with alleviation of phosphorus stress in plants (lower shoot nitrogen:phosphorus). Thus, revegetating plants have access to AM and EM fungi following dam removal, and EM formation may be especially important for plant P uptake in reservoir soils. However, availability of mycorrhizal fungi declines with distance from established plant communities. Furthermore, EM fungal communities in recently dewatered reservoirs may not be as effective at forming beneficial mycorrhizae as those from mature plant communities. Whole soil inoculum from mature plant communities may be important for the success of revegetating plants and recovery of mycorrhizal fungal communities.     

Effect of arbuscular mycorrhizal fungal isolates and organic manure on growth and mycorrhization of micropropagated Dendrocalamus asper plantlets and on spore production in their rhizosphere

The effect of three different inocula of arbuscular mycorrhizal (AM) fungi was studied on the growth, biomass, P uptake, root colonization and AM spore production in tisssue culture-raised Dendrocalamus asper (bamboo) plantlets in two types of soil: (1) sand?:?soil 1?:?1 (2) sand?:?soil?:?organic manure 1?:?1?:?0.5 (v/v). The first two inocula were isolated from the bamboo rhizosphere and the third from teak rhizosphere soil. After 12 months, significant positive effects of inoculum on shoot P concentration, root colonization and spore production were observed in the sand?:?soil medium. In the organic manure-amended medium, these parameters further improved. Amendment with organic manure highly influenced spore production (5.3 to 17.8 fold increase) and enhanced height and dry biomass of D. asper plantlets.