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Summary: Sterols have long been associated with diverse fields, such as cancer treatment, drug development, and plant growth; however, their underlying mechanisms and functions remain enigmatic. Here, we unveil a critical role played by a GmNF‐YC9‐mediated CCAAT‐box transcription complex in modulating the steroid metabolism pathway within soybeans. Specifically, this complex directly activates squalene monooxygenase (GmSQE1), which is a rate‐limiting enzyme in steroid synthesis. Our findings demonstrate that overexpression of either GmNF‐YC9 or GmSQE1 significantly enhances soybean stress tolerance, while the inhibition of SQE weakens this tolerance. Field experiments conducted over two seasons further reveal increased yields per plant in both GmNF‐YC9 and GmSQE1 overexpressing plants under drought stress conditions. This enhanced stress tolerance is attributed to the reduction of abiotic stress‐induced cell oxidative damage. Transcriptome and metabolome analyses shed light on the upregulation of multiple sterol compounds, including fucosterol and soyasaponin II, in GmNF‐YC9 and GmSQE1 overexpressing soybean plants under stress conditions. Intriguingly, the application of soybean steroids, including fucosterol and soyasaponin II, significantly improves drought tolerance in soybean, wheat, foxtail millet, and maize. These findings underscore the pivotal role of soybean steroids in countering oxidative stress in plants and offer a new research strategy for enhancing crop stress tolerance and quality from gene regulation to chemical intervention. [ABSTRACT FROM AUTHOR]

DREB transcription factor can significantly improve the plant resistance to drought, high salt, low temperature, high temperature, and other abiotic stress. A previous study showed that DREB transcription factor gene GmDREB3 from soybean can improve drought resistance in tobacco, however, whether it can improve drought resistance in wheat needs to be further investigated. In the present study, GmDREB3 was transferred to a wheat variety, Shi366 and two positive lines of the T5 generation were obtained by additive culture and molecular identification. GmDREB3‐OE (overexpression) lines conferred drought tolerance characteristics, including higher survival rates, lower malondialdehyde (MDA) content, lower relative conductivity, higher chlorophyll content, and higher proline content than Shi366 wheat plants under drought stress. The SPAD, Fv/Fm, panicle number, and grain yield of GmDREB3‐OE lines were increased but the transpiration rate was decreased, compared to the Shi366 plants in the field condition under drought stress. Significant differences in the stress indices were observed between the GmDREB3–OE lines and Shi366 wheat plants, which suggested that the GmDREB3 significantly improved wheat tolerance to drought stress. In addition, RT‐qPCR analysis indicated that GmDREB3 could enhance the expression of drought‐related genes in wheat. Therefore, GmDREB3 significantly increased drought tolerance in wheat plants along with improved physiological and agronomic traits and grain yield. [ABSTRACT FROM AUTHOR]