Field Crop 2024, Vol.7, No.2, 45-57 http://cropscipublisher.com/index.php/fc 51 6.2 Development of new traits and varieties The introduction of GM technology has led to the development of maize varieties with enhanced traits such as herbicide resistance, insect resistance, and tolerance to abiotic stresses like drought and heat. These traits have significantly improved maize yield and resilience, making it a crucial crop for food security and sustainable agriculture (Zafar et al., 2019; Yassitepe et al., 2021). Additionally, GM maize varieties have been developed to improve nutritional quality and other agronomic traits, contributing to the overall productivity and sustainability of agricultural systems (Zafar et al., 2019; Sharma et al., 2022). 6.3 Integration with other agricultural technologies The integration of GM maize with other agricultural technologies has further amplified its benefits. For instance, GM technology has been shown to complement crop rotation practices, reducing the adverse effects of continuous maize cultivation and enhancing yield gains associated with higher planting densities (Chavas et al., 2014). Moreover, the combination of GM maize with precision agriculture tools and sustainable farming practices can optimize resource use, reduce environmental impact, and increase overall agricultural efficiency (Yassitepe et al., 2021; Sharma et al., 2022). This holistic approach to integrating GM maize with other technologies underscores its potential in achieving sustainable agricultural goals. 7 Case Study 7.1 Detailed examination of GM maize use in a specific region In Mexico, the adoption of genetically modified (GM) maize hybrids has been studied extensively. Specifically, the environmental risk assessment (ERA) of GM maize hybrids MON-89×34-3 × MON-88×17-3, MON-89×34-3 × MON-Ø86×3-6, and MON-Ø86×3-6 was conducted across five ecological regions from 2009 to 2013. These hybrids were compared with conventional maize hybrids of similar genetic backgrounds. The studies revealed that the GM hybrids did not differ significantly from conventional maize in terms of early stand count, days-to-silking, days-to-anthesis, root lodging, stalk lodging, or final stand count. However, differences were noted in seedling vigor, ear height, plant height, grain moisture, and grain yield, particularly in the insect-resistant (IR) hybrids (Díaz et al., 2016). 7.2 Analysis of agronomic, economic, and environmental outcomes 7.2.1 Agronomic outcomes The adoption of GM maize in Mexico showed that the IR hybrids had higher grain yield and grain moisture compared to conventional hybrids. These phenotypic differences, however, were not expected to contribute to increased pest potential or ecological risk. The GM hybrids demonstrated similar agronomic performance to conventional maize, confirming their suitability for cultivation without additional risks (Díaz et al., 2016). 7.2.2 Economic outcomes In Colombia, the use of GM maize has led to significant economic benefits. Farmers experienced an increase in income of US $301.7 million over fifteen years. For every extra US $1 spent on GM seed relative to conventional seed, farmers gained an additional US $5.25 in extra income from growing GM maize. These income gains were primarily due to higher yields, with GM maize showing a 17.4% increase in yield compared to conventional maize (Table 1) (Brookes, 2020). Table 1 Farm income gains derived from GM cotton and maize (‘US million $) (Adopted from Brookes, 2020) Country 2018 Cumulative Cumulative area planted to GM crops (’000 ha) Maize 14.59 188.11 718940 Cotton 4.37 113.55 354460 Total 18.96 301.66 1073 400 7.2.3 Environmental outcomes The environmental impact of GM maize in Colombia included a reduction in insecticide and herbicide spraying by 779 400 kg of active ingredient, which is a 19% decrease. This reduction in chemical use also led to a 26% decrease in the Environmental Impact Quotient (EIQ), indicating a lower environmental footprint. Additionally,
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