Evaluating the germination response of Chenopodium quinoa seeds to bacterial inoculation under different germination media and salinity conditions

Quinoa is a promising crop due to its tolerance against salinity and unique nutritious value. This study aimed to evaluate the germination response of quinoa seeds to bacterial inoculation using different germination substrates and salinity levels. All possible combinations and single-microbe preparations of three bacterial isolates, Azospirrilum spp. (Azs.), Azotobacter spp. (Azt.) and Pseudomonas spp. (Psed.) were used as bacterial inoculants in both experiments. Top of paper (TP), between papers (BP), sand surface (SS), sand sub-surface (SSS), peat moss surface (PMS) and peat moss sub-surface (PMSS) were used as germination substrates in the first experiment. Four salinity levels, 0, 100, 200 and 300 mM NaCl were used in the second experiment. Top of paper (97%) and sand surface (93%) were the best substrates for germination and quinoa seeds were tolerant of NaCl based salinity upto 300 mM NaCl, with 69% germination. Seeds treated with Psed. displayed 100% germination in sand surface and no salinity. However, seeds treated with Azt. alone and in combination with Azs. and/or Psed. resulted in a better germination response at high salinity.