Pink pigmented facultative methylotrophs (PPFMs) are plant associated bacteria that utilise single carbon compounds and which have plant growth promotion potential. We have carried out the in vitro screening of two PPFM isolates obtained from paddy; PPFM 37 and PPFM 38 for abiotic stress tolerance and both the isolates showed tolerance to various levels of stresses viz., pH, salinity and water stress. Seed treatment of tomato var. Vellayani Vijay with these isolates improved germination and seedling growth. Seed treatment with PPFM 37 improved the growth parameters, and the dry weight recorded 28% increase over control. Hence the potential of these PPFM isolates for developing a farmer friendly commercial formulation for mitigating abiotic stress in crop plants can be explored

saline tolerant, water stress, PPFM, plant growth promotions, seed treatment

Numerous studies have investigated the ability of various methylotrophs to withstand abiotic stress and colonize plants under extreme climate change. In the present study, both the test organisms, viz., PPFM 37 and PPFM 38 showed tolerance to different abiotic stresses. The ability to grow at alkaline pH of 8.5 and 6% NaCl concentration indicate the potential of the isolates to tolerate salinity. Growth in media amended with 20% PEG 6000 strongly suggest the ability of the isolates to tolerate water stress and adapt to drought conditions. The isolates also exhibited plant growth promotion ability as evident from the seed treatment experiment with the tomato var. Vellayani Vijay. Seed treatment with the PPFM isolates increased germination, plant length and plant biomass. PPFM 37 exhibited considerable higher values for all the growth parameters compared to control

Aiswarya B. Nair, S. Anu Rajan, N. Chitra, V.I. Soumya, K.N. Anith and R.S. Rachanamol (2024). Abiotic Stress Tolerant Pink Pigmented Facultative Methylotrophs (PPFMS) Promote Plant Growth. Biological Forum – An International Journal, 16(6): 58-63