scholarly journals Biodiversity and distribution of arbuscular mycorrhizal fungi in Araucaria angustifolia forest

2007 ◽  
Vol 64 (4) ◽  
pp. 393-399 ◽  
Author(s):  
Milene Moreira ◽  
Dilmar Baretta ◽  
Siu Mui Tsai ◽  
Sandra Maria Gomes-da-Costa ◽  
Elke Jurandy Bran Nogueira Cardoso

Araucaria angustifolia (Bert.) O. Ktze. is an endangered Brazilian coniferous tree that has been almost exterminated in the native areas because of uncontrolled wood exploitation. This tree has been shown to be highly dependent on arbuscular mycorrhizal fungi (AMF) and, therefore, AMF may be essential for forest sustainability and biological diversity. Root colonization, density and diversity of AMF spores were assessed in two Araucaria forest stands at the State Park of Alto Ribeira (PETAR), at two sampling dates: May and October. A comparison was made between a mature native stand composed of Araucaria trees mixed into a variety of tropical trees and shrubs, without any sign of anthropogenic interference (FN) and an Araucaria stand planted in 1987 (R), which has been used as a pasture. Assessments included percent root colonization, AMF spore numbers and species richness, Simpson's dominance index (Is), and Shannon's diversity index (H). Mycorrhizal root colonization did not differ between ecosystems in May. In October, however, the native stand (FN) presented a higher colonization than the planted forest (R), and the root colonization was more intense than in May. When considering both sampling periods and forests, 27 species of AM fungi, with higher numbers of spores in FN than in R were found. Canonical discriminant analysis (CDA) indicated Shannon's diversity index as the ecological attribute that contributed the most to distinguish between forest ecosystems, with higher value of H in FN in relation to R. CDA showed to be a useful tool for the study of ecological attributes.

2006 ◽  
Vol 63 (4) ◽  
pp. 380-385 ◽  
Author(s):  
Milene Moreira ◽  
Dilmar Baretta ◽  
Siu Mui Tsai ◽  
Elke Jurandy Bran Nogueira Cardoso

Araucaria angustifolia (Bert.) O. Ktze., a native forest tree from Brazil, is under extinction risk. This tree depends on arbuscular mycorrhizal fungi for growth and development, especially in tropical low-P soils but, despite being a conifer, Araucaria does not form ectomycorrhiza, but only the arbuscular endomycorrhiza. This study aimed at surveying data on the spore density and root colonization (CR) by arbuscular mycorrhizal fungi (AMF) in Araucaria angustifolia forest ecosystems, in order to discriminate natural, implemented, and anthropic action-impacted ecosystems, by means of Canonical Discriminant Analysis (CDA). Three ecosystems representative of the Campos do Jordão (SP, Brazil) region were selected: 1. a native forest (FN); 2. a replanted Araucaria forest (R); and 3. a replanted Araucaria forest, submitted to accidental fire (RF). Rhizosphere soil and roots were sampled in May and October, 2002, for root colonization, AMF identification, and spores counts. Root percent colonization rates at first collection date were relatively low and did not differ amongst ecosystems. At the second period, FN presented higher colonization than the other two areas, with much higher figures than during the first period, for all areas. Spore density was lower in FN than in the other areas. A total of 26 AMF species were identified. The percent root colonization and spore numbers were inversely related to each other in all ecosystems. CDA indicated that there is spatial distinction among the three ecosystems in regard to the evaluated parameters.


2016 ◽  
Vol 22 ◽  
pp. 45-51
Author(s):  
KP Gabriel ◽  
HC Lakshman ◽  
Tanzima Yeasmin

Context: Arbuscular-Mycorrhizal fungi colonization in roots of many plants promotes the increased nutrient uptake especially the phosphorus from phosphorus deficient soil.Objective: To compare the efficacy of different concentration of recommended dosages of super phosphate fertilizers with inoculation of AM fungi to evaluate growth, nutrients uptake on Niger plant (Guizotia abyssinica (L.f) Cass. var, RCR-18).Materials and Methods: The effect of two Arbuscular mycorrhizal fungi Scutellospora nigra and Glomus mosseae with 4 different dosage (25%, 50%, 75%, 100% ) of superphosphate (P2O5) was treated on growth yield and nutrient uptake in Niger plant (Guizotia abyssinica (L.f) Cass. var, RCR-18) was evaluated under greenhouse conditions. Pots were watered they were harvested once in 30 days intervals. For 90 days the following readings viz., plant height, root length, biomass, grains yield, percent root colonization, spore number macro-micro nutrients contents in shoots and roots were determined.Results: Scutellospora nigra with 50% RDSP/kg showed a significant increase in the plant growth biomass of shoot and root of Guizotia abyssinica (L.f) Cass. var, RCR-18. Percent root colonization, seed number and N, P, K and Zn, Mg uptake in shoot and root.Conclusion: Overall, our results clearly suggest that synergistic and additive mechanisms involved can enhances the plant growth, nutrient uptake and adaptation to unfavorable drought soil conditions.J. bio-sci. 22: 45-51, 2014


2015 ◽  
Vol 43 (2) ◽  
pp. 488-493
Author(s):  
Zhaoyong SHI ◽  
Xubin YIN ◽  
Bede MICKAN ◽  
Fayuan WANG ◽  
Ying ZHANG ◽  
...  

Arbuscular mycorrhiza (AM) fungi are considered as an important factor in predicting plants and ecosystem responses to climate changes on a global scale. The Tibetan Plateau is the highest region on Earth with abundant natural resources and one of the most sensitive region to climate changes. To evaluate the complex response of arbuscular mycorrhizal fungi colonization and spore density to climate changes, a reciprocal translocation experiment was employed in Tibetan Plateau. The reciprocal translocation of quadrats to AM colonization and spore density were dynamic. Mycorrhizal colonization frequency presented contrary changed trend with elevations of quadrat translocation. Colonization frequency reduced or increased in majority quadrats translocated from low to high or from high to low elevation. Responses of colonization intensity to translocation of quadrats were more sensitive than colonization frequency. Arbuscular colonization showed inconsistent trend in increased or decreased quadrat. Vesicle colonization decreased with changed of quadrat from low to high elevations. However, no significant trend was observed. Although spore density was dynamic with signs of decreasing or increasing in translocated quadrats, the majority enhanced and declined respectively in descent and ascent quadrat treatments. It is crucial to understand the interactions between AM fungi and prairie grasses to accurately predict effects of climate change on these diverse and sensitive ecosystems. This study provided an opportunity for understanding the effect of climate changes on AM fungi.


Heliyon ◽  
2018 ◽  
Vol 4 (11) ◽  
pp. e00936 ◽  
Author(s):  
Boubacar A. Kountche ◽  
Mara Novero ◽  
Muhammad Jamil ◽  
Tadao Asami ◽  
Paola Bonfante ◽  
...  

2003 ◽  
Vol 69 (5) ◽  
pp. 2816-2824 ◽  
Author(s):  
Fritz Oehl ◽  
Ewald Sieverding ◽  
Kurt Ineichen ◽  
Paul Mäder ◽  
Thomas Boller ◽  
...  

ABSTRACT The impact of land use intensity on the diversity of arbuscular mycorrhizal fungi (AMF) was investigated at eight sites in the “three-country corner” of France, Germany, and Switzerland. Three sites were low-input, species-rich grasslands. Two sites represented low- to moderate-input farming with a 7-year crop rotation, and three sites represented high-input continuous maize monocropping. Representative soil samples were taken, and the AMF spores present were morphologically identified and counted. The same soil samples also served as inocula for “AMF trap cultures” with Plantago lanceolata, Trifolium pratense, and Lolium perenne. These trap cultures were established in pots in a greenhouse, and AMF root colonization and spore formation were monitored over 8 months. For the field samples, the numbers of AMF spores and species were highest in the grasslands, lower in the low- and moderate-input arable lands, and lowest in the lands with intensive continuous maize monocropping. Some AMF species occurred at all sites (“generalists”); most of them were prevalent in the intensively managed arable lands. Many other species, particularly those forming sporocarps, appeared to be specialists for grasslands. Only a few species were specialized on the arable lands with crop rotation, and only one species was restricted to the high-input maize sites. In the trap culture experiment, the rate of root colonization by AMF was highest with inocula from the permanent grasslands and lowest with those from the high-input monocropping sites. In contrast, AMF spore formation was slowest with the former inocula and fastest with the latter inocula. In conclusion, the increased land use intensity was correlated with a decrease in AMF species richness and with a preferential selection of species that colonized roots slowly but formed spores rapidly.


Author(s):  
V.P. Soniya ◽  
P.S. Bhindhu

Background: Magnesium deficiency has become a major nutritional disorder in lateritic soils of Kerala. Appropriate magnesium fertilization is the best strategy to combat deficiency issues. Apart from correcting nutritional deficiency, magnesium fertilization has an influence on the growth of beneficial microbes such as nitrogen fixing bacterias and arbuscular mycorrhizal fungi. The experiment aimed to investigate the effect of magnesium fertilization on crop yield and population rhizosphere micoflora of cowpea in lateritic soils of Kerala.Methods: A pot culture experiment was conducted with a gradient of magnesium additions ranging from 5 mg kg-1 to 80 mg kg-1 of soil along with recommended dose of fertilizers. Population of rhizobium, free living nitrogen fixing bacteria, spore count of arbuscular mycorrhizal fungi and per cent root colonization of arbuscular mycorrhizal fungi were studied during flowering. The available magnesium and magnesium uptake were also worked out during harvest. Yield and yield contributing characteristics of cowpea were measured during harvest stage.Result: Magnesium addition produced significant variations in population of rhizobium and free- living nitrogen fixing bacteria whereas spore count of AMF and per cent root colonization of AMF did not vary according to the added doses of magnesium. A higher population of rhizobium, free living nitrogen fixers, root nodules, magnesium uptake, plant height and yield were obtained in the treatment where magnesium was applied @ 10 mg kg-1 soil.


2018 ◽  
Vol 36 ◽  
pp. 63-74 ◽  
Author(s):  
Clifton P. Bueno de Mesquita ◽  
Samuel A. Sartwell ◽  
Emma V. Ordemann ◽  
Dorota L. Porazinska ◽  
Emily C. Farrer ◽  
...  

2019 ◽  
Vol 42 ◽  
pp. e42477 ◽  
Author(s):  
Rosalba Ortega Fors ◽  
Orivaldo José Saggin Júnior ◽  
Marco Aurélio Carbone Carneiro ◽  
Ricardo Luis Louro Berbara

The present study aimed to select efficient arbuscular mycorrhizal fungi (AMF) for sugarcane growth and P nutrition in four soils that spontaneously contained dark septate endophytes (DSE). The effect of nine AMF isolates was evaluated individually in sugarcane presprouted seedlings (SP81-3250) grown under greenhouse conditions for a 120-day period. The isolates that stimulated plant growth in the soils with low P availability were Acaulospora colombiana (ACOL), Claroideoglomus etunicatum (CETU), Gigaspora margarita (GMAR), Rhizophagus clarus (RCLA) and Scutellospora calospora (SCAL). Compared to the Yellow Argisol, which had the highest P level, the Red-Yellow Argisol, with an intermediate P content, increased plant height. Compared to the other treatments, inoculation with ACOL, RCLA, and SCAL resulted in higher foliar P content in plants grown in soils with high to intermediate P levels. Root colonization by AMF and DSE was verified in the plants, with the coexistence of both fungal groups in the same plant and/or root fragment. However, AMF colonization was low compared to DSE colonization. The cooccurrence of DSE and AMF was higher in the plants inoculated with ACOL, RCLA, SCAL, and Dentiscutata heterogama. ACOL, CETU, GMAR, RCLA, and SCAL are AMF isolates that have the potential to establish a mycorrhizal inoculant for sugarcane that would be effective in several soils.


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