Insight of salinity stress amelioration in oats by use of plant growth promoting bacteria

Salinity is a serious issue worldwide with negative repercussions that affects the growth and productivity of various crops. The present study aims to elucidate the beneficial effects of plant growth-promoting bacteria (Burkholderia seminalis, Azotobacter sp., Bacillus thaonhiensis, Stenotrophomonas maltophilia) alone and in different combinations in augmenting the salt tolerance (0, 50, 100, 150 and 200 mM) in oat seedlings by bio-priming of seeds with liquid bacterial inoculants under in-vitro conditions. The germination indices parameters that are germination percentage, germination speed, mean germination time were remarkably improved in the treatment where seeds were bioprimed with T₁₁: B. seminalis + S. maltophilia as compared to uninoculated control under all the varying salt concentrations. Similarly, the parameters such as shoot and root length, fresh and dry shoot and root weight and seed vigour index I and II were analysed and found that it was significantly better in the seedlings germinated from bioprimed seeds over the control seedlings. In addition, the root colonization assay of the seedlings germinated from seeds bioprimed with PGPB under unstressed condition was also carried out using scanning electron microscopy and it was observed that bio-primed oats seeds with potential liquid bacterial inoculants can negate the detrimental effect of high saline soil and promote oats seedling growth and development. It is suggested that robust field evaluation in salt affected Agro-climatic region should be carried out along with detail biosafety prefilling of PGPB before any recommendation.