Mycorrhizal Symbiosis and Soil Fertility by Leptadenia hastata from the Recovered Satara Site in the Commune of Simiri

Abstract

Soil resources are rapidly degrading in Sahel under climatic hazards and demographic pressure. Appropriate cropping strategies could mitigate and reverse the accelerated trend of soil degradation. The use of species able to rapidly associate with arbuscular mycorrhizal fungi (AMF) can restore the balance of terrestrial ecosystems. Arbuscular mycorrhizal fungi have the capacity to promote plant development in degraded environments by allowing the restoration and maintenance of soil fertility. The objective of the present study was to determine the mycorrhizal status of Leptadenia hastate and to show the importance of the mycorrhizal symbiosis in the restoration of the fertility of the degraded soils of Satara site in Simiri. Physicochemical parameters and mycorrhizal potential were determined. Ten soil and root samples were taken from a depth of 20 cm under the feet of Leptadenia hastata and another ten soil samples were taken from outside the feet in the non-forested (denuded) part. The results show that the soils in this area are characterised by a sandy-loamy texture and an acidic pH. However, organic matter, total phosphorus, assimilable phosphorus, carbon, nitrogen, sulphur and C/N ratio were higher in the Leptadenia soil compared to denuded soil, The spore density per 100g soil in Leptadenia soils (905 spores/100g of soil) is very high compared to that of bare soil (403 spores/100g of soil). Spores of Two arbuscular mycorrhizal fungi genera were found at the site: Glomus and Gigaspora with a predominance of the glomus genus. Under Leptadenia hastata, the genus Glomus is estimated at (72.07%) and Gigaspora at (27.93%). The mycorrhization frequency (F%) reached 100 in all roots of Leptadenia hastata. The mycorrhization intensity (M %) was 50.20 for all roots. Furthermore, the arbuscule content assessed by parameters (a) and (A) varies among roots. The highest value of (A %) recorded is 29.9% and the lowest value is 5.42%. As for (a %), the highest value is estimated at 62.97% and the lowest at 12.02%.