ABUNDANCE AND DISTRIBUTION OF ARBUSCULAR MYCORRHIZAL FUNGI SPECIES IN LONG-TERM SOIL FERTILITY MANAGEMENT SYSTEMS IN NORTHERN NIGERIA

Abstract Arbuscular mycorrhizal fungi (AMF) are the predominant type of mycorrhizal fungi in roots and rhizosphere soil of grass species worldwide. Grasslands are currently experiencing increasing grazing pressure, but it is not yet clear how grazing intensity and host plant grazing preference by large herbivores interact with soil- and root-associated AMF communities. Here, we tested whether the diversity and community composition of AMF in the roots and rhizosphere soil of two dominant perennial grasses grazed differently by livestock change in response to grazing intensity. We conducted a study in a long-term field experiment in which seven levels of field-manipulated grazing intensities were maintained for 13 years in a typical steppe grassland in northern China. We extracted DNA from the roots and rhizosphere soil of two dominant grasses, Leymus chinense (Trin.) Tzvel. and Stipa grandis P. Smirn, with contrasting grazing preference by sheep. AMF DNA from root and soil samples were then subjected to molecular analysis. Our results showed that AMF α-diversity (richness) at the virtual taxa (VT) level varied as a function of grazing intensity. Different VTs showed completely different responses along the gradient, one increasing, one decreasing and others showing no response. Glomeraceae was the most abundant AMF family along the grazing gradient, which fits well with the theory of disturbance tolerance of this group. In addition, sheep grazing preference for host plants did not explain a considerable variation in AMF α-diversity. However, the two grass species exhibited different community composition in their roots and rhizosphere soils. Roots exhibited a lower α-diversity and higher β-diversity within the AMF community than soils. Overall, our results suggest that long-term grazing intensity might have changed the abundance of functionally-diverse AMF taxa in favor of those with disturbance-tolerant traits. We suggest our results would be useful in informing the choice of mycorrhizal fungi indicator variables when assessing the impacts of grassland management choices on grassland ecosystem functioning.

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Effects of temperature rise (+5°C) on millet growth and mycorrhization and soil microbial community of culture

10.5194/egusphere-egu21-16406 ◽

2021 ◽

Author(s):

Sally Diatta ◽

Hassna Mboup-Founoune ◽

Sidy Diakhaté ◽

Diégane Diouf

Keyword(s):

Microbial Community ◽

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Crop Yields ◽

Pennisetum Glaucum ◽

Agricultural Practices ◽

Arbuscular Mycorrhizal ◽

Sub Saharan Africa ◽

Soil Fertility Management ◽

Vegetation Growth

Our planet is marked by significant climatic variations, particularly with the warming of temperatures and the variation in rainfall. In sub-Saharan Africa, the impacts of climate change are more pronounced because agriculture is highly dependent on climate, hence its vulnerability to climate variability (Vanluwe et al., 2011). In the context of changing environmental conditions, the use of innovative agricultural practices to contribute to plant adaptation is necessary to support food security challenges. Agroecological practices to improve crop yields and sustainable soil fertility management. Soil is the main reservoir of biodiversity as it hosts a very high diversity of interacting living species, which can be distinguished according to their size, macrofauna, mesofauna and microorganisms that constitute a particularly important component of soil (Brady and Weil, 2002), particularly for the provision of ecosystem services to humans. This work is therefore interested in studying the contribution of arbuscular mycorrhizal fungi (AMF) to the growth of millet (Pennisetum glaucum) under warmer temperature conditions and the behaviour of microbial community in soil of millet growing.Millet is grown in a plant climate chamber and inoculated with a selected mycorrhizal strain.&#160; These millet growing conditions were carried out in two different temperatures: 32&#176;C (normal temperature) and 37&#176;C (warmer temperature).The results showed that in conditions of warmer temperature the inoculation induced a significant vegetative growth of millet even with a low intensity of mycorrhization and so it improves microbial nutrient mineralization mediate vegetation growth.In soil of millet growing, a significant increase in microbial biomass with 42.7 in warmer temperature condition compared to control temperature 16.7. Results of DGGE shows also a soil abundance and SMB diversity of the total fungal community was noted under warmer temperature condition.This study showed that climate variation may affect soil symbiosis but not the potential for promoting plant growth of fungi. The use of arbuscular mycorrhizal fungi on the one hand as a biofertilizer can be an alternative in the context of reducing chemical inputs in agriculture and developing ecologically intensive agriculture (EIA) and on the other hand an adaptive practice&#160; to apprehend the predicted climate changes.

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