Maize Genomics and Genetics 2025, Vol.16, No.2, 89-97 http://cropscipublisher.com/index.php/mgg 94 6 Challenges and Future Directions of Maize Germplasm Utilization 6.1 Stuck points in the utilization process The utilization of maize germplasm resources has been a long-standing problem. Many people may have heard of the phenomenon of genetic erosion, which refers to the fact that the genetic diversity of maize is becoming narrower and narrower. This is difficult to avoid in breeding work, especially in the origin of maize, such as Mexico. Although farmers there still retain some local varieties, the protection efforts are obviously not enough, and it is becoming increasingly difficult to maintain diversity (Dyer et al., 2014). Moreover, in order to pursue stability or high yield, many breeding projects repeatedly use certain excellent varieties, which further compresses the genetic resource base that was originally not abundant (Șuteu et al., 2013). This is like fishing in the same small pond over and over again. After a long time, the fish will naturally become fewer and fewer. If new varieties want to make breakthroughs, they are not strong enough and it is difficult to make differences. In addition to genetic problems, there are also practical constraints. For example, funds. Compared with other short-term and fast-acting projects, the preservation and utilization of germplasm resources not only takes a long time to take effect, but also requires high investment, which makes it difficult for many places to continue to advance. This problem is not unique to a certain country. Many germplasm banks in developing countries are facing the dilemma of low utilization rate (Nass and Paterniani, 2000). Another thing is the technical threshold. Some advanced tools, such as double haploid technology, are indeed effective, but the cost is too high, and small breeding units can't afford it, especially in countries with limited resources (Kleiber et al., 2012). 6.2 New opportunities for technical means Fortunately, new technologies have emerged in recent years, which has opened up some space for the reuse of germplasm resources. Gene editing tools such as CRISPR-Cas9 are no longer new. Its power lies in that it can accurately manipulate the genome, adding what should be added and removing what should be removed. It can directly introduce some rare but useful traits into corn varieties, thus expanding the available genetic space (Andorf et al., 2019). As for phenotype, in the past, if you wanted to know which corn plants were drought-resistant and which were disease-resistant, you had to rely on human eyes and manual records, which was surprisingly inefficient. Now it is different. With the high-throughput phenotyping platform, not only can data be collected quickly, but also more accurately. In conjunction with genomic breeding tools, high-quality germplasm can be quickly screened according to the stress environment and more targeted strategies can be formulated (Prasanna et al., 2021). To put it bluntly, it helps speed up breeding work and also gives us more confidence to cope with climate change. 6.3 Possibility of sharing and cooperation In the final analysis, the problems of corn breeding are often not solved by a single country or institution. For example, the multinational cooperation projects led by the International Maize and Wheat Improvement Center (CIMMYT) have promoted many new stress-resistant varieties in many regions around the world, and the actual effect is quite good (Prasanna et al., 2021). Moreover, these collaborations are not just exchanges at the research level, but also involve the joint participation of public and private institutions. Some projects, such as Seed Discovery, are aimed at genetic variation in local varieties. Through genomic screening, these resources are transformed into pre-breeding materials to guide breeding on a larger scale (Gorjanc et al., 2016). In this way, not only genetic diversity is expanded, but also cooperation becomes a real driving force, rather than a slogan at the paper level. 7 Suggestions and Outlook Corn is not a crop that can be ignored. From food to feed to bioenergy, it covers almost every field of agriculture. Precisely because of its wide range of uses, the global demand for it will only grow. But the current problem is
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