The global demand for food imposes the need to increase agricultural yield without expanding the agricultural frontier or accelerating environmental degradation. The genetic improvement of crops is presented as the central strategy to optimize photosynthetic efficiency, resistance to biotics and tolerance to abiotic stresses (drought, salinity, extreme temperatures). This work evaluates the state of the art of genetic improvement technologies—from marker-assisted selection (MAS) to genomic editing using CRISPR/Cas—and aims to determine the quantitative and qualitative impact of the integration of modern genomic tools on the productivity, yield per hectare and resilience of the main commercial crops (maize, wheat, rice and soy). It carried out a systematic review and a meta-analysis of field and greenhouse trials documented in recent scientific literature. The integrated methodology: comparative data of conventional crop lines versus improved lines through functional genomics, genomic selection (GS) and gene editing (CRISPR/Cas9), yield per hectare (ton/ha), nitrogen assimilation rate, water use efficiency (WUE) and harvest index and linear mixed models and meta-regressions to isolate the genetic effects of environmental variability, evaluating the interaction Genotype × Environment (G×A). The analysis revealed significant increases in agricultural productivity directly attributed to the application of modern genetics, this is based on the yield per hectare in genetically edited varieties and selected by molecular markers in comparison with conventional genotypes; and genetic variants optimized for root architecture and stomatal conductance showed an improvement in water use efficiency, maintaining yield stability under moderate drought conditions. In conclusion, the integration of genomic editing and marker-assisted selection constitutes a fundamental pillar for future food security. The results show that genomic precision not only maximizes the theoretical maximum yield of crops, but also stabilizes production in the face of climate variability. However, it is argued that the massive adoption of these technologies faces regulatory challenges, barriers to technology transfer towards small producers and the need to maintain population genetic diversity to avoid vulnerability to new phytosanitary threats. It is concluded that plant genetics must be combined in an integral manner with sustainable agronomic management practices to reach the maximum productive potential.

This book is included in DOAB.