国家重点研发计划（2021YFD1200705, 2020YFE0202300）；中国农业科学院作物科学研究所中央级公益性科研院所基本科研业务费专项（Y2020YJ09, CAAS-ZDRW202109）；中国农业科学院科技创新工程
National Key R&D Program of China (2021YFD1200705, 2020YFE0202300)，Fundamental Research Funds for Central Non-Profit of Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (Y2020YJ09, CAAS-ZDRW202109), Innovation Program of CAAS
开展玉米重要性状主效位点的育种应用价值评估，对促进分子设计育种有效开展，提高种质资源遗传改良效率具有重要意义。针对前期工作中利用导入系1133B（热带玉米自交系Tzi8为供体亲本，温带骨干自交系B73为轮回亲本）定位的玉米株高主效位点qPEH6.02，本研究借助分子标记追踪，创制了主效位点的近等基因导入系1133BB73和1133BTzi8。以此为试验材料，在52500株/hm2、67500株/hm2和82500株/hm2三种不同密度下，开展了主效位点qPEH6.02近等基因导入系（1133BB73和1133BTzi8），及其弱优势杂交组合（同类群自交系杂交F1）和强优势杂交组合（强优势类群自交系杂交F1）的株高和产量鉴定分析。结果发现，不同种植密度下1133BTzi8较其近等基因导入系1133BB73的株高增加15.17-20.40 cm，但在其弱优势和强优势杂交组合中株高仅分别增加3.87-5.03 cm和3.23-5.97 cm。同时发现，在不同种植密度下1133BTzi8较其近等基因导入系1133BB73的小区产量增加10%以上，最高可增产15.00%；在其杂交组合中小区产量提高3%以上，最高可增产8.85%，表明主效位点qPEH6.02来自热带玉米自交系Tzi8的单倍型在提高产量方面具有潜在育种应用价值。
It is of great significance to evaluate the breeding and utilization value of the major QTL of important traits in maize to promote the effective development of molecular design breeding and improve the efficiency of genetic improvement of germplasm resources. In our early study, a major QTL, qPEH6.02, for plant height was identified using the introgression line 1133B (tropical maize inbred line Tzi8 as the donor parent, temperate founder inbred line B73 as the recurrent parent). In present study, the near-isogenic introgression lines about qPEH6.02 were developed in the target segment by molecular marker tracking. The plant height and yield of near-isogenic introgression lines (1133BB73 and 1133BTzi8), and their hybrid crosses (crossed with both weakly heterosis inbred line of the same group and strong heterosis inbred line of the different group) were analyzed at 52500 plants/hm2, 67500 plants/hm2 and 82500 plants/hm2. The results showed that the plant height of 1133BTzi8 increased by 15.17-20.40 cm compared with its near-isogenic introgression line 1133BB73 under different planting densities, but only increased by 3.87-5.03 cm and 3.23-5.97 cm in its weak and strong hybrid crosses, respectively. At the same time, it was found that the plot yield of 1133BTzi8 was increased by more than 10% and the maximum yield was increased by 15.00% compared with that of 1133BB73 under different planting densities. The plot yield increased by more than 3% and the maximum yield increased by 8.85% in the hybrid crosses. The results indicate that the haplotype of qPEH6.02 from tropical maize inbred line Tzi8 has potential breeding utilization value in improving maize yield.