Introduction.- 1. Introduction to Functional Annotation of Soil Microbiomes; Ajar Nath Yadav.- Part I. Mechanisms of Plant Growth Promotion.- 2. Plant Growth Promoting Soil Microbiomes: Current Research and Future Directions; Brendan J. McConkey.- 3. Mechanisms of Plant Growth Promotion by Rhizospheric Microbiomes; Sandeep K. Malyan.- 4. Microbes Associated with Crops: Functional Attributes for Crop Productivity; P. Veera Bramha Chari.- 5. Soil Microbes with Multifarious Plant growth Promoting attributes for Enhanced Production of Food Crops; Syed Sarfraz Hussain.- 6. Phosphorus Solubilization: Mechanisms, Recent Advancement and Future Challenge; Elhafid Nabti.- 7. Potassium Solubilization: Mechanisms, and Functional Impact on Plant Growth; Priyanka Khati.- 8. Fe-chelation and Zinc Solubilization: A Promising Approach for Cereals Biofortification; Javad Hamedi.- 9. Microbial ACC-Deaminase attributes: Role in Stress Agriculture; Mehrnoush Eskandari Torbaghan.- 10. Soil Microbes in Plant Growth Promotion and for Mitigation of Abiotic Stress of Drought; Devin Coleman-Derr.- Part II. Plant growth promotion under abiotic stress conditions.- 11. Thermotolerant Soil Microbes and Their Role in Mitigation of Heat Stress in Plants; Jianliang Huang.- 12. Microbiomes of Hypersaline Soil and their Role in Mitigation of Salt Stress; Sara Borin.- 13. Psychrotrophic Soil Microbes and their Role in Alleviation of Cold Stress in Plants; Luis AndrésYarzábal.- 14. Mitigation strategies for Abiotic Stress Tolerance in Plants through Stress tolerant PGP Microbes; Syed Sarfraz Hussain.- 15. The Omics Strategies for Abiotic Stress Responses and Microbe-Mediated Mitigation in Plants; K.R. Sridhar.- 16. Plant Probiotics: Technical challenges and emerging solutions for Enhancing food crop production; M.T. Islam.- 17. Microbial Consortium: A Promising Tools for Sustainable Agriculture; I.A. Tikhonovich.- 18. Soil Microbes as Biofertilizers for Sustainable Agriculture and Environments; Mustafeez Mujtaba Babar.- 19. Soil Microbes as Biopesticides: Agricultural Applications and Future Prospect; James N. Seiber.- 20. Mycorrhiza: Plant Growth Promoting and Biocontrol Agent Ability under the Abiotic Stress Conditions; Matthias C. Rillig.- 21. Entomopathogenic Soil Microbes for Sustainable Crop Protection; Neelam Thakur.- 22. Global Scenario of soil Microbiome Research: Current trends and Future prospect; Leonardo Schena.- Conclusion.- 23. Functional Annotation and Biotechnological Applications of Soil Microbiomes: Conclusion and Future Prospects; Ajar Nath Yadav.