Soybean, a globally significant and versatile crop, serves as a vital source of both oil and protein. However, environmental factors such as soil salinization pose substantial challenges to its cultivation, adversely affecting both yield and quality. Enhancing the salt tolerance of soybeans can mitigate yield losses and promote the development of the soybean industry. Members of the plant-specific transcription factor family NAC play crucial roles in plant adaptation to abiotic stress conditions. In this study, we screened the soybean GmNAC family genes potentially involved in the salt stress response and identified 18 GmNAC genes that may function during the early stages of salt stress. Among these, the GmNAC035 gene exhibited a rapid increase in expression within one hour of salt treatment, with its expression being induced by abscisic acid (ABA) and methyl jasmonate (MeJA), suggesting its significant role in the soybean salt stress response. We further elucidated the role of GmNAC035 in soybean salt tolerance. GmNAC035, a nuclear-localized transcriptional activator, enhances salt tolerance when overexpressed in Arabidopsis, reducing oxidative damage and boosting the expression of stress-responsive genes. It achieves this by regulating key stress response pathways, including the SOS pathway, calcium signaling, and ABA signaling. These findings highlight the potential of GmNAC035 as a genetic engineering target to improve crop salt tolerance.

Global warming has led to frequent occurrences of extreme heat, posing a huge threat to soybean (Glycine max L.) yield. As a major source of plant protein and oil, soybean is particularly sensitive to heat stress during its growth and development, especially in critical stages such as flowering and seed filling. Heat tolerance in crops is a complex trait governed by polygenic networks and environmental interactions; although existing studies have identified several heat-tolerance-related genes, the molecular regulatory networks regulating crop responses to heat stress remain elusive. This review synthesizes recent advances in soybean heat tolerance research, with a particular emphasis on physiological responses and molecular regulatory mechanisms under heat stress. We further evaluate the potential of modern technologies, including gene editing, marker-assisted selection, and pan-genomics, for the precise improvement of heat tolerance in soybean. Additionally, we outline sustainable agronomic practices and field management strategies to mitigate heat stress. The development of heat-tolerant soybean varieties depends not only on the identification of superior alleles but also requires a shift from gene-centric genetic improvement toward a system-wide solution that integrates “Genotype × Environment × Management”.