Etat de la biodiversité des spores de la rhizosphère et les paramètres de mycorhization du mil en fonction des stades phénologiques et selon les pratiques culturales

Soil microorganisms actively colonize plant roots while increasing their growth and yield. The aim of the work is to characterize arbuscular mycorrhizal fungi resulting from soil fertility management practices and their variation according to the phenological stages of millet. Samples of the soil and rootlets were taken during the tillage, run and seed stages. Morphological characterization of arbuscular mycorrhizal fungal spores and study of mycorrhizal parameters revealed that Glomus and Gigaspora are the two genera of spores resulting from soil fertility management practices. Observation with a binocular magnifying glass showed hyphae, vesicles and the presence of arbuscules on some roots. The density of the two genera of spores identified varied according to the treatments. Mulch (61, 37) has the highest average density of spores. The frequency of mycorrhization reached 100% in all treatments. For the intensity of mycorrhization, mulching also recorded the highest rate (61.06). Regarding the phenological stages, the number of spores collected at the tillering stage was more abundant with a total density of (47.72). The intensity of mycorrhization of the root cortex as well as that of the arbuscular content are also greater at the tillering stage (70.53% M and 31.19% A). The tillering stage is the phenological stage that most favors the development of AMCs and mycorrhizal symbiotic activity at the level of soil fertility management practices implemented by farmers in the W park area.