A genetic linkage map of cucumber (Cucumis sativus L) combining SRAP and ISSR markers

Sequence-related amplified polymorphism (SRAP) and Inter-simple sequence repeat (ISSR) markers are both simple and efficient maker systems adapted to many crops and for multiple purposes. In this study a genetic map based on SRAP and ISSR markers was constructed for cucumber (Cucumis sativus L.) based on the segregations of SRAP and ISSR markers in 112 plants of F2 population derived from a cross between two cucumber inbred lines PW0832 and PW0801. In the investigation of polymorphisms with 50 ISSR primers and 132 SRAP primer combinations, 13 (26%) ISSR primers and 26 (20%) SRAP primer pairs were polymorphic generating a total of 109 polymorphic markers of which 48 were ISSR and 61 were SRAP. The average polymorphic bands were four for ISSR and two for SRAP. All the 109 polymorphic markers were scored for segregation of which 86 satisfied the Mandelian segregation ratio of 3:1. These data were used to construct an integrated linkage map for cucumber consisting of 62 loci, distributed in seven linkage groups (LGs) spanning a total of 992.2 cM, with an average distance of 16.0 cM between two adjacent loci. These markers would be very useful tool for marker assisted selection in cucumber breeding as well as for studies in quantitative traits.