A genetic linkage map of sweetpotato Ipomoea batatas(L.)Lam.based on AFLP markers and the localization of stem nematode resistance gene

摘要

A genetic linkage map of sweetpotato,Ipomoea batatas(L.)Lam.,was constructed using a mapping population consisting of 202 individuals of a cross between“Xu 781”and“Xushu 18”.A total of 2602 markers,including 2601 AFLP and 1 RAPD markers and one stem nematode resistance gene were used in linkage analysis.The map of Xu 781 is based on 516 single-dose AFLP markers,332 double-dose AFLP markers and 211 double single-dose AFLP markers on 71 linkage groups with an average distance of 5.99 cM between markers.The map of Xushu 18 is based on 478 single-dose AFLP markers,229 double-dose AFLP markers and 269 double single-dose AFLP markers on 63 linkage groups with an average distance of 5.86 cM between markers.The map lengths of Xu 781 and Xushu 18 were estimated as 6339.83 cM and 5718.94 cM,respectively.Two markers,named as E2M23-3 and E2M23-15,respectively,were obtained with the primer pair E2M23,the genetic distance of which to sweetpotato stem nematode resistance gene(Spn)was 2.32 cM and 2.51 cM,respectively.