The microbiome of four soil samples from arid and semi-arid region of Saudi Arabia.. Saudi desert soil Microbiome

Saudi desert is World’s fifth largest desert stretching from Yemen to Persian Gulf and Iraq. Saudi Arabia the biggest importer of food and agricultural products is aspiring to be an oil independent economy. To improve the agricultural capacity, it is both important to understand the composition of the desert soil microbial communities both in agricultural and not agricultural desert soils. With this aim soil samples from a relatively cold semi-arid region of Abha known for agriculture and from hot arid regions of Hafr Al-Batin and Muzahmiyah were collected and studied for their microbial communities using Illumina sequencing approach. Composition of microbial communities varied remarkably from one place to another and the highest diversity was found in rhizospheric soil from Muzahmiyah followed by ABHA. Firmicutes, Proteobacteria and Actinobacteria were three main phyla detected in all the tested soil. Unlike previous reports Bacteroidetes was not a major constituent and population of Firmicutes was quite high (19-50% of the total bacteria). While, soils from agricultural region of Abha were significantly different from other samples in containing only 1% Firmicutes and three to six times higher population of Actinobacteria and Bacteroidetes, respectively. Presence of photosynthetic bacteria, ammonia oxidizers, and nitrogen fixers along with bacteria capable of surviving on simple and unlikely Carbon sources like DMF was indicative of a self-sustaining microbial community. Soil contained Gemm-3, (3% of the total bacteria), a characteristic of Sharan desert soils. Microbial community of Abha has similarity to the microbial community reported from hot Namib desert and not to the cold Antarctic desert.