| The potassium bacteria obtained from collected soil samples were isolated and identified, and then the effects of different contents from viable bacteria on the cotton seed germination rate, fresh weight, shoot and root length of seeding, the content of superoxide dismutase (SOD), peroxidase (POD) and malondialdehyde (MDA) were studied using desert sands as soil matrixes. The results showed that the potassium bacteria was Bacillus mucilaginosus. When different bacterial contents in bacterial liquid were added into desert soil, germination time of cotton seeds was 0～24 hours earlier than the control experiment. Germination rate showed a tendency to become increased first and then went decreased with the addition of bacterial content, reaching a highest value of 70.29% when the bacterial content was 0.8×108 CFU·mL-1. The length of the cotton stem and taproot were relatively increased by 0.5～1.2 cm and shortened by 0.20～0.65 cm, respectively. However, the growth of lateral root was promoted, and the fresh weight of seedlings was increased by about 0.0662～0.1582 g. In the meantime, both the content of related enzymes and malondialdehyde in the seedlings became increased or decreased to some extent. |