Acaulospora Longula Research Articles

수지상균근균이 인삼 (Panax ginseng C. A. Mey.)의 생장에 미치는 영향

본 연구에서는 5 종의 수지상균근균을 인삼(Panax ginseng C. A. Mey.)의 묘에 처리하여 인삼의 생장에 미치는 영향을 확인하였다. 수지상균근균 5종(Glomus mosseae, Glomus intraradices, Glomus etunicatum, Acaulospora longula, Acaulospora trappei)의 접종원을 발아 후 60일이 지난 인삼묘에 접종하여 120일간 키운 후 인삼의 건조중량, 지상부의 크기 및 엽록소 형광을 측정하였다. 그 결과 수지상균근균을 접종한 인삼의 생장이 대조구에 비해 높은 경향을 나타내었으며, 접종한 수지상균근균의 균주(종)에 따라 차이를 보였다. 특히, Glomus intraradices가 다른 종에 비해 인삼의 생장에 미치는 효과가 크게 나타났으며, 엽록소형광 값은 모든 종에 대하여 유의미한 차이를 보이지 않았다. The purpose of this study was to investigate effects of inoculation of arbuscular mycorrhizal fungi (AMF) on growth of Korean ginseng (Panax ginseng C. A. Mey.) seedlings. Five species of AMF (Glomus mosseae, Glomus intraradices, Glomus etunicatum, Acaulospora longula, Acaulospora trappei) were inoculated to ginseng seedlings at 60 days after ginseng seed germination. Dry weights, heights of the plants and chlorophyll fluorescence were measured at 120 days after inoculation of AMF. Dry weights and shoot heights were increased in seedlings inoculated with AMF compared to the controls without AMF. However, chlorophyll fluorescence of seedlings with AMF showed no significant difference compared to the control.

Effects of arbuscular mycorrhizal fungal species and the medium pH on the growth of Pueraria phaseoloides (Roxb.) Benth

Soil conditions may change the response of plants to inoculation with arbuscular mycorrhizal fungi (AMF). This, in turn, may influence the development of mycorrhizal associations. The effect of AM species isolated from different ecosystems was evaluated on Pueraria phaseoloides (kudzu). Experiments were conducted under controlled conditions in Leonard jars, on a substrate made of peat, rice husk, and vermiculite (1-1-1) enriched with rock phosphate plus a modified Hoagland nutrient solution. In the first experiment the initial pH of the substrate (8.0) was reduced by approximately one unit by inoculation with Kuklospora colombiana, Glomus clarum, and Glomusmanihotis. The result was the same for Acaulospora longula species when 4-morpholine ethanesulphonic acid (MES) buffer was used. The final pH of the substrate was correlated with the above-ground plant biomass production suggesting that the most effective fungus regulated the pH of the substrate. This positive interaction leads to a higher concentration of P and K in plants. When the pH of the substrate was buffered with MES, in the second experiment, the efficiency of K. colombiana was reduced, even though plants inoculated with this fungus yielded more than non-inoculated plants. G. intraradices and A. longula were favoured by buffer addition. Beneficial buffer effects on this plant resulted in lower pH, better plant P and K uptake, and higher biomass production. The best plant yield was obtained at pH 7.0 in both experiments. G. clarum and G. manihotis yielded the highest biomass production. Under the proposed conditions, AMF improved P. phaseoloides growth and pH regulation. These growth conditions may be used for the evaluation and propagation of some AMF species adding MES buffer in the nutrient solution.

Arbuscular Mycorrhizal Fungi Associated with Bisbul (Diospyros blancoi)

Bisbul (Diospyros blancoi) isa kind of edible fruit and could be beneficial as inhibitor forskin ageing process.Majority of root plants have symbiotic associations with arbuscular mycorrhizal fungi (AMF); however, AMFinbisbul has never been reported. The objective of this study was to observe AMF colonies and to identify AMF spores in bisbul tree rhizospheres and in pot-cultured Pueraria javanica. Roots and soil samples from bisbul rhizospheres were collected from three locations in Bogor area. Roots were stained using trypan blue 0.05%. Soil samples were air dried, then part of them were used for spore isolation and the rest were used for pot cultures. Spores wereisolated by wet sieving and decanting method and then continued with centrifugation. The results showed that the structures of AMF colonies in bisbul roots were arbuscules, vesicles, coiled hyphae, and internal hyphae. Isolated AMF spores were identified as Acaulospora longula, A. scrobiculata, A. tuberculata, Claroideoglomus geosporum,Funneliformis etunicatum,Gigaspora candida, G. ramisporophora, Glomus albidum, G. glomerulatum, and Scutellospora calospora. This is the first report of mycorrhizal infection in the root of bisbul and AMF association with bisbul root. Keywords:  Acaulospora, Claroideoglomus, Funneliformis, Gigaspora, Glomus,  Indonesia, Scutellospora

Uso de fungos micorrízicos arbusculares (FMA) na promoção do crescimento de mudas de pinheira (Annona squamosa L., Annonaceae)

Os fungos micorrízicos arbusculares (FMA) podem ser usados na formação de mudas frutíferas, porém o seu efeito na pinheira não é conhecido. Foi investigado o papel de dois isolados de FMA (Acaulospora longula e Gigaspora albida) na promoção do crescimento de mudas de pinheira. O delineamento experimental foi tipo inteiramente casualizado em seis tratamentos: 1) Controle não inoculado em solo; 2) Controle não inoculado em solo adubado; 3) Inoculado com A. longula em solo; 4) Inoculado com A. longula em solo adubado; 5) Inoculado com G. albida em solo; 6) Inoculado com G. albida em solo adubado, em quatro repetições, totalizando 24 unidades. Plântulas com duas folhas foram inoculadas na região das raízes com solo-inóculo fornecendo 200 esporos de G. albida ou de A. longula. Após 140 dias em casa de vegetação avaliou-se: altura, número de folhas, diâmetro do caule, área foliar, massa fresca e seca da parte aérea e radicular, colonização micorrízica e produção de esporos de FMA. Em solo não adubado, os benefícios da micorrização foram evidenciados nas mudas formando simbiose com G. albida. Em solo com vermicomposto, a micorrização não incrementou o crescimento da mudas. A micorrização com G. albida pode ser alternativa para produção de mudas de pinheira, dispensando a fertilização.

Use of mycorrhizal seedlings on recovery of mined dunes in northeastern Brazil

Abstract The exploitation of minerals from coastal dunes in northeastern Brazil requires subsequent revegetation for ecosystem recovery. In mined dunes areas, we have compared the growth of Guazuma ulmifolia and Tabebuia roseo-alba seedlings using substrates containing 10 or 15% of cattle manure, uninoculated or inoculated with a mixture of native arbuscular mycorrhizal fungi (AMF) or exotic AMF (Acaulospora longula). The inoculated plants had a higher percentage of colonization than those that were uninoculated. Plants of G. ulmifolia had the highest growth when inoculated with native AMF and fertilized with 10% manure or inoculated with A. longula and fertilized with 15% manure. In general, fertilization with 15% manure did not produce greater seedling development and had a negative effect on the effectiveness of the symbiosis. Twenty one AMF species were recorded in the planting areas at the end of the experiments, with a predominance of species that form acaulosporoid spores in areas with T. roseo-alba and gigasporoid spores in areas with G. ulmifolia plants. The incorporation of 10% cattle manure and native AMF in the substrate of T. roseo-alba and G. ulmifolia seedlings contributes to the initial establishment of plants in the field and to the incorporation of AMF propagules in the soil of the revegetated mined dunes.

Do Arbuscular Mycorrhizal Fungi Affect Metallothionein Mt2 Expression In Brassica Napus L. Roots?

Arbuscular mycorrhizal fungi are the most widespread root fungal symbionts, forming associations with the vast majority of plant species. Ectomycorrhizal development alters gene expression in plant symbionts. In this work we examined the effect of arbuscular mycorrhizal fungi spores on the growth and development of Brassica and on the expression of BnMT2 in winter rape. In a pot experiment, rape seedlings growing on different types of sterile and nonsterile soils were inoculated simultaneously with mycorrhizal fungi spores of Acaulospora longula, Glomus geosporum, Glomus mosseae and Scutellospora calospora. As compared with control plants growing in the absence of spores, ten-week-old seedlings of Brassica napus L. in sterile soil inoculated with arbuscular spores had longer shoots and higher fresh biomass of above-ground plant parts. In other types of substrates enriched with mycorrhizal fungi spores, the plants were smaller than non-inoculated plants. The presence of AMF spores stimulated the elongation growth of hypocotyls in both analyzed substrates. BnMT2 expression was highest in plants growing on the sterile substrate. Generally, the presence of mycorrhizal fungi spores appeared to have an adverse effect on the growth of rape plants.

Acclimatization of Tapeinochilos ananassae plantlets in association with arbuscular mycorrhizal fungi

The objective of this work was to assess the potential of three isolates of arbuscular mycorrhizal fungi to promote growth of micropropagated plantlets of Tapeinochilos ananassae during acclimatization. The experiment was carried out in greenhouse, in a completely randomized block design, with four inoculation treatments: non‑inoculated control and plants inoculated with Glomus etunicatum, Acaulospora longula or Gigaspora albida, with ten replicates. After 90 days, the following parameters were evaluated: survival rate, height, leaf and tiller number, leaf area, fresh and dry biomass, contents of macro‑ and micronutrients in the root and shoot, glomerospore number, and mycorrhizal colonization. The survival percentage was 100%, except for plants inoculated with G. albida (80%). The isolate G. etunicatum is more suitable for plant development, since it improves survival, growth, dry matter production, nutritional status, and vigor of T. ananassae micropropagated plants.

문안산의 목본식물과 공생하는 수지상균근균의 다양성

본 연구에서는 수지상균근균(AMF)의 형태적 및 분자 생물학적 특징을 바탕으로 문안산에 분포하는 수지상균근균의 종 다양성을 분석하였다. AMF 시료는 생강나무(Lindera obtusiloba), 국수나무(Stephanandra incisa), 쪽동백(Styrax obassis), 노린재나무(Symplocos sawafutagi)의 뿌리와 뿌리 부근의 토양에서 채취하였으며, 수수(Sorghum bicolor)를 숙주식물로 사용하여 포자를 배양하였다. 추출된 포자들의 형태 형질과 염기서열을 분석한 결과 Acaulospora longula, A. mellea, Ambispora leptoticha, Gigaspora margarita, Paraglomus occultum 등 4속 5종이 동정되었으며, 숙주식물에 따른 수지상균근균의 분포는 수종에 따라서 다른 경향을 보였다. 생강나무에서는 A. longula가, 국수나무, 쪽동백나무, 노린재나무에서는 A. leptoticha가 우점종이었다. This study was conducted to reveal the diversity of arbuscular mycorrhizal fungi (AMF) in Mt. Munan, based on the morphological and molecular characters. Soil and root samples were collected from the rhizosphere of host plants including Lindera obtusiloba, Stephanandra incisa, Styrax obassis and Symplocos sawafutagi and AMF were trap-cultured with Sorghum bicolor as a host plant in a greenhouse. The spores were extracted from the cultured soils and five species were identified using morphological and molecular characteristics; Acaulospora longula, A. mellea, Ambispora leptoticha, Gigaspora margarita and Paraglomus occultum. The distribution of AMF showed different trends according to host plants. The dominant AMF species were A. longula in L. obtusiloba, A. leptoticha in S. incisa, S. obassis and S. sawafutagi.

The role of arbuscular mycorrhizal fungi and cattle manure in the establishment of Tocoyena selloana Schum. in mined dune areas

In mined dune areas, revegetation with manured seedlings of native species is a common practice. Establishment of mycorrhized Tocoyena selloana seedlings in the mined coastal sand dunes of Northeast Brazil was tested. In greenhouse, seedlings were grown in substrates with 0, 5, 10, 15 or 20% cattle manure proportions and inoculated with Acaulospora longula, a mixture of native arbuscular mycorrhizal fungi (AMF) or uninoculated. The seedlings responded positively to the inoculation, but growth was limited in the absence of manure, independently of inoculation, and was higher with fertilizing doses ≥10%. The seedlings transplanted to the field were grown in a substrate with 16.5% manure and inoculated with A. longula or Gigaspora albida. After 13 months, 19 AMF species were identified in the rhizosphere and the inoculated plants were more colonized than those uninoculated. Plants associated to G. albida were taller and those associated to A. longula had a tendency of higher biomass than the uninoculated ones. Even though this tendency was not statistically significant, considering the effect on height and the low cost of inoculation it may be a feasible practice to maximize environment restoration.

Arbuscular mycorrhizal fungi species‐specifically affect induced plant responses to a spider mite

AbstractIt is widely recognized that arbuscular mycorrhizal fungi (AMF) improve plant growth and nutrient conditions, but their effects can vary from negative to positive depending on AMF species. Since the performance of herbivorous arthropods varies with plant quality, different AMF species should differently affect the density of herbivorous arthropods on plants and the herbivore‐induced plant responses. We examined the indirect effects of AMF on the number of spider mites (Tetranychus urticae) and the number of damaged leaves in an outdoor glass‐chamber experiment, using Lotus japonicus plants inoculated with one of four different AMF species (Gigaspora margarita, Glomus etunicatum, Gl. intraradices, and Acaulospora longula). Plants with Gi. margarita and A. longula had significantly fewer female mites than plants with Gl. etunicatum and Gl. intraradices, and plants with Gi. margarita had the fewest damaged leaves, followed by plants with A. longula,Gl. intraradices, and Gl. etunicatum. To examine species‐specific effects of AMF on herbivore‐induced plant responses, we carried out a bioassay with eggs laid by spider mites, and analyses of leaf chemicals (carbon, nitrogen, phosphorus, and total phenolics) using plants subjected or not subjected to herbivory. The bioassay showed that mite egg production and its changes following mite herbivory changed depending on the AMF species. In addition, Principal component analysis for leaf chemicals revealed not only mite‐induced changes in leaf chemical composition, but also AMF effects on the herbivore‐induced response in a species‐specific way. Thus, we need to pay more attention to the species identity of AMF as an important factor in determining the strength of effects of belowground AMF on the performance and/or preferences of aboveground herbivores.

Effect of Organic Farming on Spore Diversity of Arbuscular Mycorrhizal Fungi and Glomalin in Soil

In this study, eight soil samples were collected from organic and conventional farms in a central area of South Korea. Spore communities of arbuscular mycorrhizal fungi (AMF) and glomalin, a glycoprotein produced by AMF, were analyzed. Spores of Glomus clarum, G. etunicatum, G. mosseae, G. sp., Acaulospora longula, A. spinosa, Gigaspora margarita, and Paraglomus occultum were identified at the study sites, based on morphological and molecular characteristics. While Acaulospora longula was the most dominant species in soils at organic farms, Paraglomus occultum was the most dominant species in soils at conventional farms. Species diversity and species number in AMF communities found in soils from organic farms were significantly higher than in soils from conventional farms. Glomalin was also extracted from soil samples collected at organic and conventional farms and was analyzed using both Bradford and enzyme-linked immunosorbent assays. The glomalin content in soils from organic farms was significantly higher than in soils from conventional farms. These results indicate that agricultural practices significantly affect AMF abundance and community structure.

Mycorrhizal occurrence and responsiveness of tall fescue and wheatgrass are affected by the source of phosphorus fertilizer and fungal inoculation

We assessed colonization and mycorrhizal growth responses (MR) of wheatgrass and tall fescue growing with and without indigenous soil microorganisms (from Argentinean Pampas) as affected for inoculation with the non-indigenous arbuscular mycorrhizal fungi (AMF) Acaulospora longula or Glomus claroideum and for fertilization with superphosphate (SP) or rock phosphate (RP). Inoculation increased growth, P uptake and MR in plants growing without indigenous microorganisms. The highest MR was determined in non-fertilized tall fescue plants inoculated with G. claroideum. When inoculation and RP were added together to the fumigated soil, plant growth, mycorrhiza and MR were significantly stimulated over the single treatments. When plants were grown in non-fumigated soil, no treatment effects were detected. The introduction of G. claroideum or A. longula under like-field conditions would not cause plant growth increments under field conditions. Emphasis could be put to select an effective indigenous AMF, and reinforcing the mycorrhizal population in soils supplied with RP.

Occurrence and coexistence of arbuscular mycorrhizal fungi and dark septate fungi in aquatic macrophytes in a tropical river–floodplain system

In this study, carried out in four water bodies in the Upper Paraná River floodplain, we assessed the occurrence of root colonization by arbuscular mycorrhizal fungi (AMF) and dark septate fungi (DSF), as well as the AMF species richness associated with 24 species of aquatic macrophytes belonging to different life forms. AMF were found in nine species of macrophytes and DSF in 16 species among the 24 investigated. AM colonization occurred mainly in eudicotiledons (five of the six species evaluated) and the Paris morphology was the most common type. Co-occurrence of AMF and DSF was observed in seven species of macrophytes (Commelinaceae sp. 1, Limnobium laevigatum (H.B.K. ex Willd) Heine, Hygrophila cf. costata, Myriophyllum brasiliense (Camb), Polygonum acuminatum Kunth, P. ferrugineum Wedd and P. stelligerum Cham). Four species of macrophytes ( Pistia stratiotes L., Eichhornia crassipes (Mart.) Solms, Egeria najas Planch and Nymphaea amazonum Mart. & Zucc) were not colonized by any type of fungi. In total, 27 morphotypes of AMF were recorded, and spores occurred both in the rhizosphere of macrophytes whose roots were internally colonized by AMF and in non-colonized macrophytes. Acaulospora delicata, Acaulospora aff. laevis, Acaulospora longula, Glomus lamellosum, Glomus luteum and NID 1 (a non-identified species) were the most frequent species. Samples collected close to the roots of N. amazonum had the highest AMF richness (20 species), but this plant was not colonized by fungi. A species richness curve indicated that more root-associated fungi than reported here are likely present in this floodplain.

Assessment of the mycorrhizal community in the rhizosphere of maize ( Zea mays L.) genotypes contrasting for phosphorus efficiency in the acid savannas of Brazil using denaturing gradient gel electrophoresis (DGGE)

Community structure of indigenous arbuscular mycorrhizal fungi (AMF) in the rhizosphere of tropical maize genotypes contrasting for phosphorus efficiency was evaluated using denaturing gradient gel electrophoresis (DGGE). Fragments of AMF ribosomal DNA (rDNA) were amplified using nested PCR with fungal universal primers and ITS (internal transcribed spacer) specific primers for Acaulosporaceae, Glomaceae and Gigasporaceae. ITS-Acaulosporaceae and Glomaceae-specific primers and DGGE were efficient in differentiating the composition of mycorrhizal communities. Maize genotypes had a greater influence on the rhizosphere mycorrhizal community than the level of P in the soil. DGGE profiles of maize roots revealed bands that were present only in P efficient genotypes (L3 and HT3060), suggesting that some mycorrhizal groups were stimulated by P efficient maize genotypes. Acaulospora longula, A. rugosa, A. scrobiculata, A. morrowiae and Glomus caledonium were found only in the rhizosphere of P efficient maize genotypes cultivated in low P soils. A greater number of mycorrhizal DGGE bands were found in soil samples from no-till maize than conventional tillage. Effective mycorrhizal colonization of crops may influence the maize yield under Brazilian savanna acid soils by modulating the capacity of different cultivars to tolerate P deficiency.

Uso de vermicomposto favorece o crescimento de mudas de gravioleira (Annona muricata L. 'Morada') associadas a fungos micorrízicos arbusculares

A gravioleira, cujos frutos apresentam elevado potencial para exportação, é de fácil adaptação ao Semi-Árido nordestino, e a sua produção, economicamente importante, vem sendo estimulada. O uso de adubos orgânicos associados à inoculação com fungos micorrízicos arbusculares (FMA) pode ser útil na formação de mudas frutíferas, porém o efeito da adição de adubo na simbiose com gravioleira (Annona muricata L. 'Morada') não é conhecido. Foi investigado o efeito de FMA multiplicado em substrato com resíduo orgânico na formação de mudas de gravioleira mantidas em substratos com fertilizante. O delineamento foi inteiramente casualizado, em fatorial de 2×5: 2 substratos (solo sem ou com 10% de vermicomposto) e cinco tratamentos de inoculação (Acaulospora longula Spain & Schenck e Gigaspora albida Schenck & Smith produzidos em substratos com ou sem resíduo orgânico e controle não inoculado), com quatro repetições. Após 102 dias, avaliou-se: massa seca da parte aérea e radicular, altura, diâmetro do caule, taxa de crescimento, produção de esporos de FMA e de glomalina, atividade enzimática do solo, respiração microbiana, colonização micorrízica total, arbuscular e hifálica. Em geral, a inoculação com FMA estimulou o crescimento, mas no tratamento adubado as mudas em simbiose com G. albida não foram beneficiadas pela associação. O uso de vermicomposto estimulou a colonização micorrízica, a respiração microbiana, a atividade enzimática e a produção de glomalina no solo, porém reduziu a esporulação de A. longula. A utilização de FMA e vermicomposto pode constituir alternativa na produção de mudas de gravioleira, pois reduziu à metade o tempo de formação das mudas e pode reduzir em 75% a dose de adubo a ser aplicada. No entanto, a escolha de FMA compatíveis com o hospedeiro é indispensável para garantir respostas positivas. A aplicação conjunta de FMA e adubo orgânico também pode melhorar a qualidade do solo, contribuindo para a produção sustentável de mudas desta e de outras fruteiras.

Mycorrhizal dependency of mangaba tree under increasing phosphorus levels

The objective of this study was to evaluate the mycorrhizal dependency of mangaba tree (Hancornia speciosa) plantlets, under increasing levels of phosphorus fertilization. The experimental design was completely randomized in a 4×5 factorial arrangement with three mycorrhizal fungi inocula - Gigaspora margarita, Glomus etunicatum, or a pool of native mycorrhizal fungi (Acaulospora longula, Glomus clarum, Gigaspora albida, Paraglomus sp.) -, and a nonmycorrhizal control, in combination with five levels of phosphorus applied to the substrate: 0, 25, 50, 75, and 100 mg kg-1. After 180 days of growth, plantlets with inoculation of native mycorrhizal pool produced more shoot and root dry biomass and had higher shoot phosphorus content and accumulation. The noninoculated control showed the lowest values, independently of the phosphorus level. The highest relative mycorrhizal dependency occurred with the inoculation of native mycorrhizal fungi. Plants with mycorrhizal fungi did not respond to phosphorus addition above 50 mg kg-1. Mangaba tree is highly dependent on mycorrhiza, but the degree of dependency varies according to phosphorus levels and fungal inocula. In general, mangaba tree is more responsive to mycorrhizal fungi inoculation than to phosphorus addition.

Eficiência de fungos micorrízicos arbusculares isolados de solos de áreas de mineração de bauxita no crescimento inicial de espécies nativas

Fungos micorrízicos arbusculares (FMAs), estabelecendo simbioses eficientes com plantas, desempenham papel importante na sustentabilidade dos ecossistemas e podem ser manejados para a revegetação bem sucedida de áreas degradadas. A eficiência da simbiose está relacionada não só aos genótipos dos simbiontes, i.e, FMA e espécie vegetal, como também às condições ambientais que influenciam a expressão da relação simbiótica. Assim, o primeiro passo visando ao manejo de simbioses eficientes é estudar a variabilidade de FMAs quanto à eficiência com diferentes espécies vegetais. Neste estudo, avaliaram-se a colonização micorrízica e a eficiência simbiótica de isolados de FMAs obtidos de áreas de mineração de bauxita em reabilitação em dois ambientes (campo e serra), no crescimento de mudas de duas espécies pioneiras [aroeira (Schinus terebenthifolius) e trema (Trema micrantha)] e de duas espécies secundárias iniciais [açoita-cavalo (Luehea grandiflora) e sesbânia (Sesbania virgata)], em solo de baixa fertilidade. O experimento foi realizado em casa de vegetação, por 120 dias. Para cada espécie vegetal, foram aplicados 10 tratamentos de inoculação com FMAs (isolados de FMAs ou de sua mistura): Acaulospora longula, Paraglomus occultum, Glomus sp., Gigaspora sp., Acaulospora spinosa e a mistura destes, todos oriundos de área de campo; e Acaulospora scrobiculata, Paraglomus occultum, Glomus sp. e a mistura destes, todos oriundos de área de serra. Para comparação, foram acrescentados ainda um tratamento-referência inoculado com Glomus etunicatum eficiente e um tratamento não-inoculado como controle. Plantas de todas as espécies apresentaram crescimento reduzido na ausência de FMAs (controle), porém beneficiaram-se de modo diferenciado dos tratamentos de inoculação. Todos os isolados, ou sua mistura, foram eficientes em promover o crescimento de sesbânia, enquanto para trema e aroeira somente um isolado de Glomus sp. não foi eficiente. Para o açoita-cavalo, os dois isolados de Glomus sp. estudados foram ineficientes. Nenhum dos FMAs isolados da área de mineração de bauxita promoveu crescimento superior ao obtido com o tratamento-referência com G. etunicatum. No entanto, os isolados do campo Gigaspora sp., Paraglomus occultum e Acaulospora spinosa foram tão eficientes quanto G. etunicatum em promover crescimento das quatro espécies vegetais. Os resultados indicam que mesmo áreas tão degradadas como aquelas submetidas à mineração de bauxita podem conter populações de FMA eficientes, que podem contribuir para reabilitação da área.

Production and infectivity of inoculum of arbuscular mycorrhizal fungi multiplied in a substrate supplemented with Tris-HCl buffer

The effect of adding Tris-HCl buffer on production and infectivity of AMF inoculum was investigated. Sporulation of Glomus etunicatum, Acaulospora longula and Gigaspora albida was improved in solution with buffer. The infectivity of G. etunicatum increased after storage, what suggests that the inoculum of this isolate is benefited by storage.

Efeito de fungos micorrízicos arbusculares no crescimento de mudas de Leucaena leucocephala (Lam.) de Wit. em solos de caatinga sob impacto de mineração de cobre

Os fungos micorrízicos arbusculares (FMA) podem conferir às plantas maior tolerância a metais pesados e têm sido indicados para uso em processos de revegetação. Foi avaliado o efeito de FMA no crescimento de mudas de Leucaena leucocephala (leucena), em solos de áreas de caatinga impactados por mineração de cobre (Mineradora Caraíba, Município de Jaguarari, Bahia). O delineamento foi do tipo inteiramente casualizado, em arranjo fatorial 3 × 4, correspondendo ao substrato das áreas de empréstimo (local em que a camada superficial do solo foi removida) e de rejeito de cobre, ao solo de caatinga preservada e a quatro tratamentos de inoculação (controle não-inoculado, inoculado com Glomus etunicatum, com Acaulospora longula e com a mistura dos dois fungos), com cinco repetições. Independentemente do tratamento de inoculação, o substrato da área de empréstimo mostrou-se mais indicado para o preparo de mudas de leucena, enquanto o da área de rejeito foi inviável para o cultivo dessa planta e estabelecimento da associação micorrízica. Embora infectivo, G. etunicatum foi ineficiente em promover o crescimento de leucena nas áreas impactadas, enquanto os FMA nativos, A. longula e a mistura dos fungos contribuíram para o desenvolvimento das mudas.

Enraizamento in vitro de Anthurium andraeanum Lindl. cv. Eidibel e aclimatização com fungos micorrízicos arbusculares

The aim of the present study was to evaluate A. andraeanum in vitro rooting and acclimatization with arbuscular mycorrhizal fungi (AMF). In order to induce rooting, the consistence and ionic strenght of MS medium modified (5,71 µM de NAA) were tested: solid MS; liquid MS; solid half-strenght MS and liquid half-strength MS. After 60 days, plants were acclimatized in association with the AMF Gigaspora albida, Glomus etunicatum, Acaulospora longula, multiple inoculum or without AMF (control treatment). The liquid nutritive medium containing the complete concentration of MS salts induced better plant development, specially with regard to root number. Mycorrhization reduced the acclimatization impact, favoring water and phosphorus absorption, as well as plant growth, specially those associated with multiple inoculum.