Abstract
Sugar beet is one of China's major cash crops, and Inner Mongolia has become an important sugar base in China. However, cultivation of sugar beet in Inner Mongolia could be improved, as it contains 1.06 million hectares of saline-alkali land, accounting for 11.4% of the total arable land in the region. This saline-alkali land challenges the potential for sugar-beet cultivation as excessive concentrations of saline and alkaline substances, in addition to ionic components, have been demonstrated to have a detrimental effect on the growth of crops, including sugar beet. In sugar beet, excessive concentrations of saline and alkaline substances impact the normal metabolism of sugar beets, thereby inhibiting their growth and development. The present study posits that the utilization of a microbial fertilizer has the potential to mitigate the repercussions of saline-alkali stress. The application of microbial fertilizer has been demonstrated to exert a substantial influence on the accumulation of soluble sugars, soluble proteins and free proline in sugar beet roots and leaves. This study demonstrated a decrease in malondialdehyde (MDA) content and an increase in the K(+)/Na(+) ratio following treatment with a microbial fertilizer. Furthermore, increased activity of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) enzymes was observed. These changes induced an increase in the contents of indole-3-acetic acid (IAA), gibberellic acid (GA) and zeatin (ZR) and a decrease in abscisic acid (ABA) content. The results also indicate an increase in the seedling retention rate and fresh weight of sugar beets.