Authors:I. El Aymani, S. El Gabardi, M. Artib, M. Chliyeh, K. Selmaoui, A. Ouazzani Touhami, R. Benkirane and A. Douira
The diversity of endomycorrhizal fungi in the rhizosphere of Crocus
sativus has been studied at five sites in the Taliouine region
(Tinfat), located in Taroudant Province (Morocco), according to the number of
years of soil exploitation by Saffron cultivation. In all sites, the roots of
Crocus sativus carry structures of endomycorrhizal fungi.
Root mycorrhizal frequencies are very high in site 1 (93.33%); site 2 (96.67%);
site 4 (90%) and in site 6 (93.33%). In these sites, the spore density is,
respectively, 39, 58, 138, 99 spores / 100 g of soil. The frequency of root
mycorrhization is lower at the site (76.66%) which also exhibited a spore
density of 27 spores / 100 g of soil.
The identification of isolated spores made it possible to note the presence of 36
species belonging to 6 genera: Glomus (15 species),
Acaulospora (10 species), Scutellospora (6
species), Gigaspora (2 species), Pacispora (2
species), Entrophospora (1 species). Species such as
Glomus clarum, G. etunicatum, G.
aggregatum, G. intraradices, Acaulospora
laevis, Scutellospora coralloidea, were present in
all studied sites.
The greatest richness of MA fungi was registers in the site at four successive
years of exploitation by Saffron (24 species), with a Shannon diversity index H
‘= 2.82 which is the highest among all studied sites, followed by the site at
six years of occupation by Saffron (21 species), with H ‘= 2.61, while the
lowest number of species was recorded in sites of two, three and ten years of
exploitation of sol by Saffron, with H ‘= 1.77, respectively; 2.12 and 2.44.
This decrease in endomycorrhizal species richness confirms that Crocus
sativus residues are probably the cause. In fact, the prolonged
occupation of plots with safrana has an allelopathic effect on mycoflora and on
the yield of Saffron.