Int.J.Curr.Microbiol.App.Sci (2020) 9(12): 711-717 711 Original Research Article https://doi.org/10.20546/ijcmas.2020.912.085 Assessment of Soil Health of Different Blocks of Samastipur, Bihar by Root Health Bio Assay Test Kumari Sushma Mahto* and Dinesh Rai Department of Plant Pathology, Dr. Rajendra Prasad Central Agricultural University, Pusa, Samastipur, Bihar, India *Corresponding author ABSTRACT Introduction Soil quality is proportional with the soil functions such as it is providing a medium for the proper plant growth and development, furnishing the supply of water and storage of nutrients. Soil functions are an amalgamation of several activities such as decomposition of organic matter, nutrient cycling, storage of water and its release, and the regulation of naturally present biological soil population (Ritz et al., 2009). These soil indicators are dynamic properties and are very much sensitive and affecting in nature to the management of land, occurring natural interferences and presence of chemical contaminants in the soil. Soil health is the potentiality of the soil to perform as an important living body of soil with the integration of ecosystem and the use of land energy for the maintenance of biological or living productivity, quality of environment, and the promotion of total health of all living biota of lithosphere (Doran and Zeiss, 2000). International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 9 Number 12 (2020) Journal homepage: http://www.ijcmas.com A study was undertaken to explore and analyze the soil health of different blocks of Samastipur. Five soil samples from each cultivated and uncultivated fields were collected from different villages of Samastipur namely Deopar (Block- Pusa), Motipur (Block- Tajpur), Aadharpur (Block- Tajpur), Dudhpura (Block- Samastipur) and Dadpur (Block- Samastipur) and different physico-chemical properties were assessed. Root health bio- assay test was also performed in pots under greenhouse conditions. The soil of Deopar and Dadpur of both cultivated and uncultivated soil samples showed best ratings among the tested all the soil samples. In growth promotion study, overall plant growth promotion was better in cultivated fields soil samples compared to uncultivated fields. Maximum root length (13.0 cm) was observed in Motipur; shoot length (62.6 cm) in Deopar; root weight (18.3 g) in Dadpur and maximum shoot weight (44.0 g) Aadharpur in cultivated fields. The soil samples of both cultivated and uncultivated fields were assessed on the different parameters i.e. soil texture, pH, organic carbon and organic matter. The results revealed that, pH ranging from 7.2 to 8.2 and 7.4 to 7.9 in cultivated and uncultivated fields respectively. Maximum organic carbon (0.69 %) and organic matter (1.18 %) observed in cultivated fields of Deopar. Keywords Soil health, Root health bio assay test, Plant growth promotion, pH, Organic carbon Accepted: 07 November 2020 Available Online: 10 December 2020 Article Info