Current maize (Zea mays L.) breeding methods and the limited germplasm infusion and mixing may slow the rate of genetic gain in the future. Using inter‐heterotic group composites for maize inbred development has been questioned because of the issue of choosing appropriate testers. However, three observations can be revisited to facilitate the exploration of alternative methods. First, since the adoption of single‐cross hybrids and the establishment of heterotic groups, the amount of heterosis has only been increasing slightly. Second, genomic analysis indicated the frequencies of the favorable alleles had significantly increased after a century's breeding. Third, the divergence of maize heterotic groups was preceded by the merging of landraces and diverse inbreds, after which three major heterotic groups were established. The objective of this study was to design different scenarios to generate inter‐heterotic group composites and evaluate their usefulness in the commercial breeding program. We investigated two methods: the inter‐heterotic group composite method (termed as super population [SupPop]) and the modified SupPop method (ModiSP, that is, backcrossing SupPop lines with elite inbreds). The results showed that the best scenario for the SupPop method was to use the SupPop inbreds to cross with a tester from the B14 group. When all four heterotic groups were mixed, the favored tester was from stiff stalk. However, ModiSP showed a higher chance of producing the best yield performance. These empirical results suggest that solutions can be proposed to identify the testers so that using inter‐heterotic group composites for inbred development can be considered.

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玉米自交育新方法一：杂种优势群体间的组合及测试者选择

目前玉米（玉米L.) 育种方法以及有限的种质注入和混合可能会减慢未来遗传增益的速度。由于选择合适的测试者的问题，使用杂种优势群体间的复合材料进行玉米自交系开发一直受到质疑。然而，可以重新审视三个观察结果，以促进替代方法的探索。首先，自从采用单交杂种和建立杂种优势群体以来，杂种优势的数量仅略有增加。其次，基因组分析表明，经过一个世纪的育种，有利等位基因的频率显着增加。第三，玉米杂种优势群体的分化先于地方品种和不同自交系的合并，之后建立了三个主要的杂种优势群体。本研究的目的是设计不同的方案来生成杂种优势群体间的复合材料，并评估它们在商业育种计划中的有用性。我们研究了两种方法：杂种优势群体间复合方法（称为超级群体[SupPop]）和改良的SupPop方法（ModiSP，即将SupPop品系与优良近交系回交）。结果表明，SupPop 方法的最佳方案是使用 SupPop 近交系与 B14 组的测试者杂交。当所有四个杂种优势群体混合时，首选的测试者来自硬茎。然而，ModiSP 显示出产生最佳产量表现的机会更高。这些实证结果表明，可以提出解决方案来识别测试者，以便可以考虑使用杂种优势群体间的复合材料进行近交发育。