Sandplain soils on the south coast of Western Australia have low inherent fertility, which is mainly due to poor nutrient retention caused by insufficient clay and organic colloidal material. ...Previous research has shown the benefits in nutrient levels and retention from adding clay to sandplain soils; however, there is almost no information on the addition of organic amendments. A field experiment was established at the Esperance Downs Research Station, Western Australian, in May 2010, to assess the effects of wheat straw （WS） and chicken manure （CM） biochars and compost with and without phosphorus （P） addition on soil properties and crop production over five growing seasons. The five seasons alternated between winter and summer crops. The CM and WS biochar and compost treatments significantly increased crop yields and P uptake in 3, 2 and 1 of the five seasons, respectively. The yield increases （P 〈 0.05） were no more than 8%. By the end of the third season, no differences in crop yields were found that could be attributed to the organic amendments. The addition of P increased crop yields in each winter cropping season. Phosphorus addition explained more than 30% of the variation in crop yields. Despite marginal P levels and summer drought conditions, arbuscular mycorrhizal root colonisation was not affected by the organic amendments. There were no significant interactions between the organic amendments and P addition in terms of crop yields, P uptake or P uptake efficiency. We conclude that much of the effect of the organic amendments was due to direct nutrient addition which dissipated over time.
The present study aimed to compare the impact of arbuscular mycorrhizal (AM) fungi on plant growth and heavy-metal (HM)-uptake when both plant and fungal symbionts originated either from contaminated ...or uncontaminated sites. HM-tolerance of six clones of the grass
Agrostis capillaris and three isolates of the AM fungus
Glomus intraradices of different origin was first tested separately. Plant clones from the vicinity of a lead smelter showed a consistently high HM-tolerance, whereas the control clones varied in their ability to cope with HMs. The AM isolate from the contaminated substrate also performed better under HM-stress than the isolates from uncontaminated soils. All
A. capillaris clones were then grown in a contaminated substrate, uninoculated or inoculated either with a tolerant or non-tolerant
G. intraradices isolate. Clones from the uncontaminated site accumulated considerably more HMs in their shoots and roots, regardless of inoculation. The effect of AM inoculation on plant growth and HM-uptake depended on the particular combination of plant clone and fungal isolate, without clear differences between tolerant and non-tolerant clones.
FungalRoot Soudzilovskaia, Nadejda A.; Vaessen, Stijn; Barcelo, Milagros ...
The New phytologist,
August 2020, Letnik:
227, Številka:
3
Journal Article
Recenzirano
Odprti dostop
• Testing of ecological, biogeographical and phylogenetic hypotheses of mycorrhizal traits requires a comprehensive reference dataset about plant mycorrhizal associations.
• Here we present a ...database, FungalRoot, which summarizes publicly available data about vascular plant mycorrhizal type and intensity of root colonization by mycorrhizal fungi, accompanied with rich metadata. We compiled and digitized data about plant mycorrhizal colonization in nine widespread languages.
• The present version of the FungalRoot database contains 36 303 species-by-site observations for 14 870 plant species, tripling the previously available compiled information about plant mycorrhizal associations. Based on these data, we provide a recommended list of genuslevel plant mycorrhizal associations, based on the majority of data for species and careful analysis of conflicting data. The majority of ectomycorrhizal and ericoid mycorrhizal plants are trees (92%) and shrubs (85%), respectively. The majority of arbuscular and nonmycorrhizal plant species are herbaceous (50% and 70%, respectively).
• Our publicly available database is a powerful resource for mycorrhizal scientists and ecologists. It features possibilities for dynamic updating and addition of data about plant mycorrhizal associations. The new database will promote research on plant and fungal biogeography and evolution, and on links between above- and belowground biodiversity and ecosystem functioning.
Glomalin-related soil protein (GRSP) are a glycoprotein mainly produced by arbuscular mycorrhizal (AM) fungi. GRSP are deposited in the soil after being released from AM fungal hyphae, and they are ...believed to improve soil health and carbon (C) storage. However, it is unclear how fertilizer and mycorrhiza suppression affect the content of easily extractable (EE-GRSP) and total glomalin-related protein (T-GRSP) in arid grassland soil. We conducted a 3-yr in situ study to determine the main and interactive effects of nitrogen (N), phosphorus (P), and fungicide (benomyl) addition on EE-GRSP and T-GRSP content in the soil of desert steppe in Northwest China. To further explore the mechanisms influencing GRSP content, the plant community, soil fertility and the AM fungal traits were also identified. Following 3 years of fertilizer and fungicide application, P addition had a negative influence on EE-GRSP content (−12.50%), whereas N addition had no significant effect. Fungicide application reduced EE-GRSP (−18.47%) and T-GRSP content (−18.36%) regardless of N and P addition. By altering the extraradical hyphal length of AM fungi, P and fungicide application decreased the EE-GRSP and T-GRSP content without affecting the vegetation or soil characteristics. Overall, this study provides insights into the dynamics of GRSP in response to soil nutrient enrichment and fungicide application in a resource-limited grassland ecosystem.
Peat is the most common substrate used in nurseries despite being a very expensive and a non-renewable material. Peat replacement with biochar could be a sound environmental practice, as it is ...produced from waste biomass, but evaluation of biochar as a potting substrate is needed. Ratios of peat:biochar of 100:0, 70:30, 30:70 (BC0, BC30, and BC70, respectively), two fertilizer rates (FERT1, FERT2), and arbuscular mycorrhizal fungi (AMF) inoculation were tested on potted Pelargonium plants. Plant growth, flowering, bio-physiological and nutritional responses, and root mycorrhization were evaluated. The BC30 mixture did not affect plant growth compared with pure peat. However, BC30 in combination with FERT2 treatment was more effective in enhancing nitrogen (N) and chlorophyll (CHL) leaf concentrations, and leaf and flower numbers. The BC70 mixture depressed plant growth, flowering traits, and root mycorrhization. Leaf N concentration was below the sufficiency range reported for Pelargonium growth. Leaf concentration of phosphorous (P) was adequate in pure peat and in BC30 but it dropped close to sub-optimal values in BC70. The pH value of the mixtures lowered P availability, though in BC30 the mycorrhizal activity could have allowed adequate P plant uptake. In BC70 plants, the deficiency of both N and P might be a reason for the observed growth reduction. The inoculation of the substrate with selected AMF improved plant growth (higher dry biomass, greater floral clusters, larger and more abundant leaves) and quality resulting in unstressed (lower electrolyte leakage and higher relative water content values) and greener leaves (low L(∗) and C(∗), high CHL content) and in more intensely colored flowers. We conclude that biochar can be applied in nursery/potted plant production provided that the proportion in the peat mixture does not exceed 30%. Furthermore, AMF inoculation contributed to achieving the best plant performance in 30% biochar amended medium.
Common bean (
Phaseolus vulgaris
L.) stands as the main leguminous crop cultivated in South-Kivu Province, DR Congo. However, there is a scarcity of information regarding the soil mycorrhizal ...potential, natural mycorrhization, and the spore density of arbuscular mycorrhizal fungi (AMF) associated with
P. vulgaris
in South-Kivu Province. Sample of rhizospheric soil and roots were collected from famer’s field in three localities in two territories namely Kabare and Walungu. The goal was to determine the natural mycorrhization rate of common beans, AM fungi spore density, and the soil mycorrhizal potential in relation with soil chemical properties. Our findings revealed that bean root colonization was notably high in Katana, Kavumu and Miti, while being comparatively low in Lurhala, Walungu centre, and Nduba. Katana and Kavumu exhibited a high number of spores (242.9 ± 37.8 and 183 ± 13.1 spores.100 g
−1
soil, respectively) compared to other sites. Soil mycorrhizal potential was higher in Katana, Kavumu, and Miti sites, located in Kabare territory (10.8 ± 0.7, 9 ± 1.3 and 8.8 ± 0.9 AM fungi propagula g
−1
soil). The AM fungi potential was positively and significantly correlated with bean mycorrhizal colonization (
p
<
0.0001
). As soil phosphorus (
P
) content increased, mycorrhization frequency and intensity significantly decreased (
r
= − 0.69,
p
< 0.0001 and
r
= − 0.54,
p
= 0.002, respectively), along with the soil mycorrhizal potential (
r
= -0.87,
p
< 0.0001), regardless the study sites. Conversely, soil pH positively influenced mycorrhizal colonization (
r
= 0.73,
p
< 0.0001 and
r
= 0.54,
p
= 0.002, respectively), and the soil mycorrhizal potential (
r
= 0.78,
p
< 0.0001). This study underscores a substantial variation in common bean mycorrhizal status and soil mycorrhizal potential across sites. To enhance common bean productivity, it is recommended to consider site-specific identification of AM fungi morphotypes and inoculum production.
Background and aims Arbuscular mycorrhizal fungi (AMF) are important for plant nutrient and water acquisition. Much is known about how nutrient addition and environment affect AMF, but little is ...known about nutrient by environment interactions. We measured AMF colonization with nutrient additions and along an environmental gradient to assess these interactions. Methods We measured AMF colonization in roots of little bluestem (Schizachyrium scoparium (Michx) Nash) with nutrient addition and across an environmental gradient. We assessed how AMF colonization changed across different fertilization treatments, and used ridge regression to determine nutrient, environment, and nutrient by environment interaction variables that predicted AMF colonization. Results The addition of nitrogen decreased AMF colonization, while mean annual temperature (MAT) and soil pH both positively predicted the percentage of AMF colonization in Schizachyrium scoparium. Additionally, we found an interaction term between MAT and phosphorus treatments that significantly affected percent AMF colonization. Conclusions Our results show the importance of understanding environmental conditions on AMF as well as nutrient by environment interactions when assessing how AMF respond to nutrient addition. Here we present a full-factorial nutrient addition study along an environmental gradient to assess how AMF root colonization is influenced by abiotic factors in addition to nutrients.
The functional groups of plants that characterize different phases of succession are expected to show differences in root distribution, fine‐root traits and degrees of association with arbuscular ...mycorrhizal (AM) fungi. The relationship involving fine‐root traits and AM fungi that regulate the nutrient acquisition potential among different plant functional groups are still not well understood. We assessed fine‐root morphology, AM fungal variables and soil fertility in grassland, secondary forest and mature forest in Atlantic, Araucaria and Pantanal ecosystems in Brazil. Soil cores were collected at 0–10 and 10–20 cm depths. Fine roots were extracted from soil by sieving and root morphological traits and AM colonization were determined. The AM spores were extracted from soil and counted. In all ecosystems, soil fertility, fine‐root mass and root diameter increased with the succession, while root length, specific root length, root‐hair length, root‐hair incidence, AM colonization and AM spore density decreased. These results suggest that plant species from early stages of tropical succession with inherent rapid growth invest in fine roots and maintain a high degree of AM colonization in order to increase the capacity for nutrient acquisition. Conversely, fine root morphological characteristics and low degree of AM colonization exhibited by plants of the later stages of succession lead toward a low nutrient uptake capacity that combine with their typical low growth rates. Abstract in Portuguese is available at http://www.blackwell‐synergy.com/loi/btp.
The benefits of inoculation with six arbuscular mycorrhizal fungi (AMF) isolates (
Glomus aggregatum, G. fasciculatum, G. intraradices, G. manihotis, G. mosseae
, and
G. verriculosum)
were ...investigated on seedlings of
Acacia senegal
(L.) Willd., a multipurpose tree legume highly valued for arabic gum production. Mycorrhizal root colonization, plant growth and relative mycorrhizal dependency (RMD) were measured in
A. senegal
seedlings growing in soils from three geographical sites in Senegal (Dahra, Bambey and Goudiry) and two soil conditions (sterilized vs unsterilized) in the glasshouse. The impact of inoculation on mycorrhizal root colonization and plant growth depended on AMF isolates, soil origins and soil conditions. Mycorrhizal root colonization and plant growth were increased in sterilized soils regardless of soil origin and AMF isolates. The degree of RMD of
A. senegal
seedlings varied with soil origin, soil condition and AMF isolates.
A. senegal
showed the highest RMD values, reaching a maximum of 45 %, when inoculated with
G. manihotis
. However, in unsterilized soils, no significant effect of AMF inoculation on plant growth was observed despite significant root colonization with certain AMF isolates in Dahra and Goudiry soils. This indicates that the most infective AMF isolates were not the most effective and unsterilized soils may contain effective mycorrhizal propagules. In conclusion, it is important to consider the native mycorrhizal component of the soils before harnessing mycorrhizal inoculation programs for sustainable agroforestry systems.
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