为明确新选玉米自交系的配合力特性及其杂种优势类群，以24个新育成自交系为被测系，与NSS、SS、黄改及改良瑞德类群的5个测验种按NC-Ⅱ遗传交配设计组配120个杂交组合，在2个地点开展田间试验。GCA分析表明冀603、DH116、B132、冀H158、SW3-2和冀22S274等6个自交系表现突出，利用潜力较高；SCA分析筛选出PH6WC×冀H522、PH4CV×冀H453、PH4CV×冀H524、昌7-2×冀603、郑58×冀PBA、PH6WC×冀H453、昌7-2×D7和PH6WC×冀H521等优势组合；TCA分析筛选出冀22S274×DH116、冀5041×DH116和B132×冀1877等优异组合。基于籽粒产量SCA相对效应值和SNP标记分别进行聚类分析，均将24个自交系划分到2个杂种优势类群和6个亚群。本研究明确了新选自交系的杂种优势类群和组配方向，为进一步指导种质改良和新品种选育提供了理论基础。

To clarify the combining ability characteristics and heterosis utilization patterns of newly selected maize inbred lines, 24 novel inbred lines were crossed with 5 testers from four heterotic groups (NSS, SS, HuangZaoSi improved lines, and improved Reid) using the NC-II genetic mating design, generating 120 hybrid combinations. Field trials were conducted in Shijiazhuang, Hebei Province, and Xinxiang, Henan Province. General combining ability (GCA) analysis identified Ji603, DH116, B132, JiH158, SW3-2, and Ji22S274 as elite inbred lines with high breeding potential. Notably. Specific combining ability (SCA) analysis screened eight elite hybrids, including PH6WC×JiH522, PH4CV×JiH453, PH4CV×JiH524, Chang7-2×Ji603, Zheng58×JiPBA, PH6WC×JiH453, Chang7-2×D7, and PH6WC×JiH521. Total combining ability (TCA) analysis further selected three outstanding hybrids (Ji22S274×DH116, Ji5041×DH116, and B132×Ji1877). Cluster analysis based on grain yield SCA effects categorized the 24 inbred lines into six subgroups within two heterotic groups. This study clarifies the heterotic group classification of the novel inbred lines and provides a theoretical foundation for guiding germplasm improvement and new hybrid breeding.

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河北省重大专项（21326319D），河北省农林科学院基本科研业务费项目（2021060202），河北省农林科学院科技创新人才队伍建设项目博士基金（C23R0301，C23R0309），国家玉米产业技术体系石家庄综合试验站项目（CARS-02-58）