<p>Grapevine genetic transformation is pivotal in molecular breeding and gene function analysis. Immature zygotic embryos from ‘Chardonnay’ grapes have proven to be effective transformation materials. This approach offers a shorter transformation period and higher efficiency compared to somatic embryo systems. The objective of this study is to refine the genetic transformation system for grape immature zygotic embryos, building on prior research. Key challenges include optimizing transformation efficiency, minimizing false positives, and ensuring uniformity in transformed materials. To standardize transformation efficiency, the optimal GA₃ concentration for seed dehiscence was first determined. This enables the seeds to meet transformation requirements, allowing large-scale transformation experiments to be conducted. Subsequently, transformation conditions were optimized, and the transgenic material was cultured in a shallow-layer system, employing an <i>Agrobacterium</i>-mediated method. Shallow-layer culture significantly boosts transformation efficiency. We noticed that ‘Chardonnay’ roots are hypersensitive to antibiotics; consequently, we developed “solid substrate-antibiotic solution culture” that enhance screening efficiency of transgenic plantlets. This method reduces the transformation timeline, increases efficiency to 50% and enables the production of transgenic plants within two months. This work provides a methodological foundation for grape gene function studies, molecular breeding, and the creation of mutant libraries. By means of genetic transformation, genes can be further explored and studied, enabling precise resistance breeding and enhancing plant quality.</p>