Eco. Env. & Cons. 29 (3) : 2023; pp. (1075-1079) Copyright@ EM International ISSN 0971–765X Evaluation of the Growth and Tolerance of Pseudomonades Isolates under Different pH and Salt Concentrations Dilip Kumar Chaurasiya 1 , Sangita Sahni 1* , Bishun Deo Prasad 2 and Birendra Kumar 1 1 Department of Plant Pathology, 2 Department of Agricultural Biotechnology & Molecular Biology, CBS&H Dr Rajendra Prasad Central Agricultural University, Pusa, Samastipur 848 125, Bihar, India (Received 4 January, 2023; Accepted 28 February, 2023) ABSTRACT The study aimed to isolate pseudomonads from soil samples and evaluate their growth under varying pH levels and NaCl concentrations. The results showed that 46.66% of the 15 isolates showed high growth under 50 mM salinity, while 13.33% showed high growth at 100 mM salinity and 33.33% were able to tolerate up to 150 mM salinity with reduced growth. All isolates showed higher growth at pH 7 and 8, while 20% of isolated showed high growth even at pH 9 and 10. The study showed the potential of candidate isolates in pH and salt stress. These isolates having Plant growth-promoting rhizobacteria (PGPR) may be utilized to augment plant growth under pH and salt stress conditions. Key words: Plant growth-promoting rhizobacteria (PGPR), Lentil (Lens culinaris M), Salt tolerant, pH, Soil salinity Introduction Salt stress is one of the major environmental factors limiting plant growth and productivity, particularly in coastal and arid regions. The cultivation of lentils (Lens culinaris M) in India can be negatively im- pacted by high pH levels and elevated salt concen- trations in the soil (Singh et al., 2022). These condi- tions can cause reduced growth and decreased yields for the crop. Studies have shown that high pH values can lead to toxicity of essential nutrients and ion imbalances that negatively affect plant growth and health (Kumar et al., 2021). Additionally, high salt levels can cause soil salinization and increase the risk of drought stress for the lentil plants, result- ing in reduced yields (Hossain et al., 2017; Singh and Husen, 2019). To mitigate these negative effects, farmers in India can implement practices such as regular soil testing and management, irrigation management, and the use of salt-tolerant lentil vari- eties. To overcome this challenge, researchers have focused on the identification and characterization of plant growth-promoting rhizobacteria (PGPR) that are able to tolerate high salt concentrations (Kumawat et al., 2022). PGPR are beneficial microor- ganisms that colonize the root system of plants and provide a range of benefits such as increased nutri- ent uptake, improved stress tolerance, and enhanced growth (Shultana et al., 2022). In the context of soil salinity, the isolation and use of rhizobacteria that promote plant growth and can tolerate high salt lev- els could be a key factor in mitigating the harmful effects of soil salinity on plant growth and survival (Banerjee et al., 2019). Recently, there has been a growing interest in the use of PGPR as biostimulants for crop improvement in salt-affected soils. How- DOI No.: http://doi.org/10.53550/EEC.2023.v29i03.009