Diversity and abundance of arbuscular mycorrhizal fungi under different plant and soil properties in Sidama, southern Ethiopia

Native forests but not agroforestry systems preserve arbuscular mycorrhizal fungal species richness in southern Ethiopia

“…In addition to the possible confounding differences in the growth rhythm between the agroforestry and khat monoculture systems, a higher plant-available phosphorus supply under agroforestry than in the other land-use types likely decreased the AMF species richness (Xiang et al 2014 ) and spore density (Kahiluoto et al 2001 ). In contrast to our study, however, Dobo et al ( 2016a ) reported both increasing spore density and AMF species diversity with an increase in plant-available soil phosphorus in the Sidama zone; a negative influence of very low phosphorus availability (18.4 ppm by Dobo et al vs. 56.4 ppm NaHCO 3 -extractable phosphorus here) on AM formation and effectiveness has also been previously shown (e.g., Kahiluoto et al 2000 ). Rather than by differences in soil properties, the minor or lack of differences between khat monocropping and agroforestry despite the greater plant diversity (Burrows and Pfleger 2002 ) in agroforestry and higher land-use intensity (Oehl et al 2010 ) under khat monocropping may be explained by the difference in host plant species identity (Mathimaran et al 2007 ).…”

“…One of the causes underlying the dominance of the two genera Acaulospora (35.5% of identified species) and Glomus (21% of identified species) as also found in other studies in similar agroecosystems (Belay et al 2013 , 2014 , 2015 ; Dobo et al 2016a ), other tropical systems (Stürmer and Siqueira 2011 ), and Chinese forests (Zhao et al 2001 ) as well as in temperate regions (Oehl et al 2017 ) is that these genera are the most speciose AMF genera. To date, 50 species have been described from each of these genera in tropical forests (Marinho et al 2018 ).…”

“…These results were somewhat lower than those found by Muleta et al ( 2007 , 2008 ) in agroforestry and monocultured coffee systems in southwestern Ethiopia (0.04–1.2-g −1 soil) and by Stürmer and Siqueira ( 2011 ) in distinct land-use systems in the western Brazilian Amazon (0.51–2.3-g −1 soil). However, very high spore densities were reported by Birhane et al ( 2018 ) in dry Afromontane forest in northern Ethiopia (4.5 spores g −1 soil) and by Dobo et al ( 2016a ) in a similar study area and in similar land-use types as in the current study (4.3 to 7.5 g −1 of soil). Consequently, the spore densities found here obviously represent those beyond the sporulation period, and the differences among the land-use types reflect relative rather than absolute differences.…”

“…The finding of 37 AMF species (morphotypes) belonging to 12 genera of Glomeromycota identified in this study was in the range of previous studies conducted in similar land-use systems in the region. For example, 29 AMF species were identified in Sidama, southern Ethiopia, by Dobo et al ( 2016a ), and Belay et al ( 2013 , 2015 ) found 42 species associated with different land-use types in Ethiopia. However, somewhat lower numbers of AMF species, 12 to 17, were identified by Jefwa et al ( 2009 , 2012 ) in soils from indigenous forests to croplands in southern Kenya.…”

Alterations to arbuscular mycorrhizal fungal community composition is driven by warming at specific elevations

“…Previous studies have shown that there were dominant genera in AMF communities, such as Glomus and Acaulospora (Dobo, Asefa & Asfaw, 2016;Belay, Vestberg & Assefa, 2013). Our study found that the relative abundance and occurrence frequency of Glomus and Acaulospora were higher whether in CK or OTC than other genera except the occurrence frequency of Glomus at 4,170 m, which had been reported before (Sturmer & Siqueira, 2011;Coutinho et al, 2015).…”