A segregation distortion locus located on linkage group 4 of the chickpea genetic map P. Castro • J. Rubio • A. Cabrera • T. Milla ´n • J. Gil Received: 4 November 2009 / Accepted: 17 January 2011 / Published online: 30 January 2011 Ó Springer Science+Business Media B.V. 2011 Abstract A chickpea F 2 population of 593 plants derived from the intraspecific cross ILC3279 9 WR315 was genotyped for markers closely linked to quantitative trait loci (QTLs) for ascochyta blight resistance (QTL AR1 and QTL AR2 located on linkage group 4 and QTL AR3 on linkage group 2). All the markers located on linkage group 4 exhibited strongly distorted segregation with respect to the expected Mendelian inheritance, towards the male parental line. This skewed segregation was also observed in a second F 2 population of 50 plants derived from the same cross, confirming the presence of a region of distorted segregation on this linkage group and its heritability. The most skewed markers were SC-Y17 and TA72, which were tightly linked to each other, indicating that they may both be closely associated with the genetic factor responsible for segregation distortion in chickpea. To attempt to explain the non- Mendelian segregation, by identifying factors to which it could be attributed, three different chi- square tests were carried out to test different hypotheses using the data obtained from examining co-dominant markers associated with segregation distortion. According to our results, the distorted segregation could be caused by gametophytic factors that affect either male or female gametes. Pollen fertility and meiosis were also analysed to determine their relationship with segregation distortion; how- ever, these not seem to be inducing factors in the non- Mendelian segregation reported in this study. Keywords Segregation distortion  Molecular markers  Gametic selection  Chickpea Introduction Segregation distortion can be defined as a deviation of observed marker genotypic frequencies from the expected Mendelian ratio in a segregating population. It is a relatively common phenomenon in genetic mapping and it has been reported in both animals and plants (Taylor and Ingvarsson 2003; Song et al. 2006). It can be detected for almost any kind of genetic marker (Xu et al. 1997) and it seems to be particularly common in wide crosses (Winter et al. 1999). Often markers showing segregation distorted towards the same parent are clustered in small genomic regions of specific linkage groups (LGs), known as segregation distortion regions (SDRs). These SDRs seem to be related to the presence of segregation distortion loci that result in gametic or zygotic selection. In maize, 14 SDRs have been detected, some of them located in genomic P. Castro (&)  J. Rubio A ´ rea de Mejora y Biotecnologı ´a, IFAPA, Centro ‘Alameda del Obispo’, Apdo. 3092, 14080 Co ´rdoba, Spain e-mail: patriciar.castro@juntadeandalucia.es A. Cabrera  T. Milla ´n  J. Gil Dpto Gene ´tica, Universidad de Co ´rdoba, Campus de Rabanales Edificio C5 2a planta, 14071 Co ´rdoba, Spain 123 Euphytica (2011) 179:515–523 DOI 10.1007/s10681-011-0356-7