Genetic analysis of heterosis for maize grain yield and its components in a set of SSSL testcross populations

• Published in: Euphytica 2016-07, Vol.210 (2), p.181-193
• Main Authors: Wei, Xiaoyi, Lu, Xiaomin, Zhang, Zhanhui, Xu, Mengmeng, Mao, Keju, Li, Weihua, Wei, Feng, Sun, Pei, Tang, Jihua
• Format: Article
• Language: English
• Subjects: Agricultural production; Analysis; Biomedical and Life Sciences; Biotechnology; Corn; Crop yield; Gene loci; Gene mapping; Genetic aspects; Life Sciences; Plant Genetics and Genomics; Plant Pathology; Plant Physiology; Plant Sciences; Quantitative genetics; Zea mays
• ISSN: 0014-2336; 1573-5060
• DOI: 10.1007/s10681-016-1695-1

The present study aimed to dissect the genetic basis of heterosis for grain yield and its components in maize ( Zea mays L.). Quantitative trait loci (QTL) and heterotic loci (HL) were analyzed using a set of 203 single segment substitution lines (SSSLs) and its testcross population in three environments. Forty-one QTL were identified as responsible for grain yield, ear length, ear diameter, row number, kernel number per row, and 100-kernel weight in the SSSLs population, and 17 QTL were conserved across the three environments. In the heterosis analysis, 36 HL were identified for grain yield and five yield-related traits in the test population in the three environments. Among the HL, only six (16.7 %) for ear length, kernel number per row, 100-kernel weight, and grain yield were consistent with the results of QTL mapping. In addition, 16.7 % of the heterotic loci showed a dominant effect and 83.3 % showed an over-dominant effect. The results implied that dominance and over-dominance were two important components of heterosis in maize grain yield and yield-related traits in the present testcross population.