Robustness test analysis.

Under the new development pattern, both "digital" and "low-carbon" development have entered the fast track, and digital transformation has become an important path to promote green development and enhance total factor productivity in agriculture. Based on the data of agricultural companies, this paper empirically verifies the impact of voluntary environmental regulations on total factor productivity. The empirical results show that voluntary environmental regulation has a significant positive impact on total factor productivity of agribusiness. In the mechanistic analysis, it is found that voluntary environmental regulations accelerate the digital transformation process of firms, which in turn increases their total factor productivity. In addition, the level of government environmental concern contributes to the increase of voluntary environmental regulations on firms’ total factor productivity. The findings have practical implications for the sustainable development of agribusiness, providing empirical evidence for policy formulation and adjustment, and helping the agricultural economy to achieve high-quality development.