Maize Genomics and Genetics 2025, Vol.16, No.1, 34-44 http://cropscipublisher.com/index.php/mgg 40 2021). Moreover, public-private partnerships have played a crucial role in the dissemination of these stress-tolerant varieties, ensuring they reach the farmers who need them most efficiently (Prasanna et al., 2020; Prasanna et al., 2021). Figure 3 Maize germplasm phenotyping/testing network of CIMMYT and partners in the tropics of ESA, Latin America, and Asia (Adopted from Prasanna et al., 2021) 7 Challenges in the Exploration and Utilization of Fresh Corn Germplasm Resources 7.1 Limited access to germplasm resources due to conservation policies and management restrictions Access to germplasm resources is often restricted by conservation policies and management practices, which can limit the availability of diverse genetic materials for breeding programs. The conservation of genetic variability is crucial, but the high costs and long-term nature of these activities pose significant challenges. This issue is not confined to a single region but affects many developing countries, where the utilization of germplasm banks remains low (Nass and Paterniani, 2000). Additionally, the proprietary nature of many inbred lines, protected by patents and plant variety protection acts, further restricts access until these protections expire (Mikel and Dudley, 2006). 7.2 Over-reliance on specific germplasm resources, leading to genetic bottlenecks The over-reliance on a narrow genetic base in maize breeding has led to genetic bottlenecks, which limit the potential for genetic improvement and adaptation. Much of the current maize germplasm originates from a few progenitor lines, resulting in a limited genetic pool (Mikel and Dudley, 2006). This narrow genetic base restricts the capacity to increase genetic gain through conventional breeding methods, making it essential to integrate a broader range of genetic resources into breeding programs (He and Li, 2020). 7.3 Technological and resource constraints in developing countries Developing countries face significant technological and resource constraints that hinder the effective utilization of germplasm resources. The adoption of advanced breeding technologies, such as doubled haploid (DH) technology, is often limited by the high costs and technical requirements associated with artificial chromosome duplication (Kleiber et al., 2012). Moreover, the lack of infrastructure and expertise in these regions further exacerbates the challenges, making it difficult to implement efficient germplasm conservation and breeding strategies (Nass and Paterniani, 2000). 7.4 Impact of climate change on the adaptability of germplasm resources Climate change poses a significant threat to the adaptability of germplasm resources. The changing environmental conditions can affect the viability and performance of maize germplasm, necessitating the development of cultivars with enhanced resistance and tolerance to biotic and abiotic stresses (He and Li, 2020). The long-term conservation of seeds under varying storage conditions also impacts seed viability, with significant differences
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