Diversity of arbuscular mycorrhizal fungi in the rhizosphere of <i>Coffea arabica</i> in the Republic of Yemen

Abstract

Objective: This study describes the status of mycorrhizal fungi in coffee (Coffea arabica) in the Yemeni ecosystems. Methodology and results: Soil samples were extracted from the rhizosphere of the coffee tree groves in several regions of Yemen. The frequency and the level of colonization of the arbuscular mycorrhizal fungi (AMF) inside the root bark were measured by assigning an index of mycorrhization from 0 to 5 (Derkowska et al., 2008). The results showed that the AM fungal colonization structures were hyphae, coils and vesicles. The mycorrhizal frequency and intensity reached respectively 100 and 48 % in the Taiz 2 site. The highest spore density was in the order of 100 spores/100 g of soil and the genus Glomus was dominant. The tentative identification test of VAM (Vesicular Arbuscular Mycorrhizae) species, isolated from the rhizosphere of the coffee trees, revealed the presence of five fungal species:, Glomus proliferum, G. etunicatum, Acaulospora sporocarpia, Acaulospora sp.1, Archeospora sp. 1, Scutellospora nigra. Conclusion and application of results: In all the studied sites the coffee roots were mycorrhized. These results demonstrate the existence of opportunities for the application of controlled mycorrhization in the coffee Seedlings nurseries.

Composition of the root mycorrhizal community associated with Coffea arabica in Fifa Mountains (Jazan region, Saudi Arabia)

“…This suggests that AMF play an important role for the sustainability of C. Arabica plantations in this arid environment. These findings are consistent with earlier reports on AMF associated with the roots of Arabica coffee trees in Yemen . A higher mycorrhizal colonization was registered in site 2.…”

“…Our results show that the density of AMF spores was relatively low, which is common for coffee species in arid lands . These low densities of AMF spores may be due to the presence of species with low sporulation capacity in those environments.…”

“…AMF can protect coffee from root pathogens and mitigate the effects of extreme variations in temperature, pH, soil salinity, and water stress . A number of studies have described the relationship of mycorrhizal symbio­sis with coffee . Siqueira et al showed that coffee have high mycorrhizal dependency, especially during the seedling formation stage.…”

“…The AMF communities of C. arabica in its introduced range have been well studied . However, studies on AMF communities of C. arabica in its natural range is very scarce and most of them were based on morphological identification of AMF . The most frequent AMF genera found to be associated with C. arabica are Acaulospora and Glomus .…”

Does Arbuscular Mycorrhiza Determine Soil Microbial Functionality in Nutrient-Limited Mediterranean Arid Ecosystems?

“…Sporulation in AMF occurs when the development of the mycelium begins to be limited by nutrients and is a highly carbon demanding process. This may explain why the number of AMF spores in the rhizosphere varies among plant species and, for the same plant species, among sites [36][37][38]. Apart from the rate of spore formation, the number of AMF spores in a soil also depends on the rates of spore germination and degradation [39].…”