Mapping QTLs of resistance to head splitting in cabbage (Brassica oleracea L.var. capitata L.) Wenxing Pang . Xiaonan Li . Su Ryun Choi . Van Dan Nguyen . Vignesh Dhandapani . Yoon-Young Kim . Nirala Ramchiary . Jin Gyu Kim . David Edwards . Jacqueline Batley . Jonghyun Na . HyeRan Kim . Yong Pyo Lim Received: 26 December 2014 / Accepted: 4 May 2015 Ó Springer Science+Business Media Dordrecht 2015 Abstract Cabbage head splitting can greatly affect both the quality and commercial value of cabbage (Brassica oleracea). To detect the genetic basis of head-splitting resistance, a genetic map was construct- ed using an F 2 population derived by crossing ‘‘748’’ (head-splitting-resistant inbred line) and ‘‘747’’ (head- splitting-susceptible inbred line). The map spans 830.9 cM and comprises 270 markers distributed in nine linkage groups, which correspond to the nine chromosomes of B. oleracea. The average distance between adjacent markers was 3.6 cM. A total of six quantitative trait loci (QTLs) conferring resistance to head splitting were detected in chromosome 2, 4, and 6. Two QTLs, SPL-2-1 and SPL-4-1, on chromosomes 2 and 4, respectively, were detected in the experiments over 2 years, suggesting that these two potential loci were important for governing the head-splitting resis- tance trait. Markers BRPGM0676 and BRMS137, which were tightly linked with head-splitting resis- tance, were detected in the conserved QTL SPL-2-1 region using bulked segregant analysis. Synteny analysis showed that SPL-2-1 was anchored to a 3.18- Mb genomic region of the B. oleracea genome, homologous to crucifer ancestral karyotype E block in chromosome 1 of Arabidopsis thaliana. Moreover, using a field emission scanning electron microscope, significant differences were observed between the two parental lines in terms of cell structures. Line ‘‘747’’ had thinner cell wall, lower cell density, larger cell size, Wenxing Pang and Xiaonan Li have contributed equally to this work. Electronic supplementary material The online version of this article (doi:10.1007/s11032-015-0318-1) contains supple- mentary material, which is available to authorized users. W. Pang Á X. Li Á S. R. Choi Á V. D. Nguyen Á V. Dhandapani Á Y.-Y. Kim Á J. G. Kim Á Y. P. Lim (&) Molecular Genetics and Genomics Lab, Department of Horticulture, Chungnam National University, Daejeon 305-764, Republic of Korea e-mail: yplim@cnu.ac.kr N. Ramchiary Translational and Evolutionary Genomics Lab, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India D. Edwards School of Agriculture and Food Sciences, University of Queensland, Brisbane, QLD 4072, Australia J. Batley School of Plant Biology, University of Western Australia, Crawley, WA 6009, Australia J. Na Research and Development, Nunhems Korea, Anseong 456-883, Republic of Korea H. Kim Plant Systems Engineering Research Center, Cabbage Genomics Assisted Breeding Supporting Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 305-806, Republic of Korea 123 Mol Breeding (2015) 35:126 DOI 10.1007/s11032-015-0318-1