Isolation and characterization of beneficial soil microorganisms from Mediterranean regions to use in agroecosystems.

Anthropogenic activities pose a significant threat to the natural capital of the soil which includes its fertility, biodiversity and ability to support ecosystems. In this context the use of indigenous beneficial soil microbiota can firmly increase the resilience of these systems. Under field conditions plants interact with a multitude of microorganisms. Among them plant growth-promoting bacteria (PGPB) and arbuscular mycorrhizal fungi (AMF) represent a fundamental component of soil fertility through their role in plant growth, health and productivity. The main goal of the PRIMA project is to promote support a farming system that boosts the efficiency of water use and aid soil conservation and fertility in arid and semiarid climates, compatible with the development of smallholder conservation agriculture by introducing the rational use of beneficial soil microbiota and an intercropping system using perennial such as cactus pear and short-term species such as Leguminosae and cereals. In the present work, it is reported the isolation, the molecular identification, and the physiological characterization of rhizospheric bacteria from three Morocco sites differing for their climatic conditions (humid, semi-arid and arid) as well as the isolation and the molecular identification of AMF spores from Algeria and Tunisia. To find good PGPB candidates that will be later applied in field conditions, different assays on the bacterial strains, such as growth compatibility test and germination and in vivo tests using sorghum plants, have been carried out. Finally, the AMF spores have been propagated to obtain a pure inoculum that will be tested individually or in consortium on different plant species. Simultaneously in vivo test on cactus pear inoculated or not with AMF was carried out. The aim of this experiment is to observe if the presence of the mycorrhizal fungi can improve the development and stress resistance of the plants during the early growth stages.