التوصيف الجزيئي لبكتيريا الازوتوباكتر والرازبيوم القاطنة في بعض ترب الجبل الأخضر- ليبيا

Abstract

This study aimed to explore and characterize the molecular strains of some types of nitrogen-fixing bacteria in the soil of the Al-Jabal Al-Akhdar region in Libya. It included the isolation of Azotobater and Rhizobium bacteria from three main areas: Al-Safsaf Agricultural Station, Al-Dhia area, and Al-Haniya area. Soil samples were collected randomly, and analyzes were conducted in sterile conditions in the microbiology laboratory in the Department of Soil and Water at the College of Agriculture, using specialized nutritional environments for each type of bacteria. The results showed the isolation of different strains of Azotobater bacteria, including Azotobater chroococcum and Azotobater vinelandii from willow soil, and other strains such as Azotobater chroococcum strain LMG 8756and Azotobater vinelandii strain NBRC 102612from salt soil in the Al-Haniya area, in addition to Azotobater beijerinckii strain ICMP 8673 from salt soil. And sodic In the peak area. Regarding Rhizobium bacteria, different strains were isolated from the roots of leguminous plants in the willow plant, such as Rhizobium oryziradicis B 7from the roots of the chickpea plant, Rhizobium qilianshanense B9-SJKEL, B10-SJKEL from the roots of the lentil plant, and Rhizobium leguminosarum B. 11-SJKEL from the roots of the bean plant . The importance of these bacteria, which specialize in biological nitrogen fixation (BNF), lies in their ability to convert atmospheric nitrogen into usable compounds, which enhances soil fertility. From a geological perspective, this process contributes to the incorporation of nitrogen into the lithosphere and soil, which affects the natural nitrogen cycle and enhances the composition of the soil and its chemical properties. Studying these bacteria enhances the geoscientist's understanding of the interactions of the lithosphere with the biosphere and the role of microbial processes in supporting the sustainability of soil and ecosystems. The study recommended increasing the cultivation of leguminous plants and enhancing the use of biofertilizers instead of harmful chemical fertilizers, while employing genetic engineering to improve the efficiency of bacteria and enhance their resistance to harsh conditions. She also stressed the importance of documenting microbial diversity in Al Jabal Al Akhdar and supporting sustainable agriculture through cooperation between researchers and farmers to scientifically apply research results. Finally, the strains were registered in the International Gene Bank in South Korea under the name of the researcher and supervisors, which reflects the importance of the study in linking scientific research with scientific application and supporting sustainable agricultural development.