Isolation and Screening of Soybean Rhizobia and Their Effects on Soybean Nodulation and Plant Growth in Saline-Alkali Soil

Abstract

Soybean is a vital food crop, and saline-alkali soil represents a valuable arable land resource. Rhizobia inoculation can improve the tolerance of soybean to salt stress, potentially increasing yield in saline-alkali soil. A strain of rhizobia DY31-8 was isolated from saline-alkali soil using salt-tolerant soybean as a host. This strain demonstrated the ability to survive at temperatures ranging from 14°C to 42°C and in salt concentrations of 1%–3%. It also exhibited certain antibiotic resistance and independent auxin production. Soybean inoculation experiments demonstrated that DY31-8 forms a reciprocal symbiosis with soybean roots and significantly promotes plant growth. This study provides insights for the screening and application of soybean rhizobia in saline-alkali soil.