Construction of Molecular Genetic Linkage Map of Sugarcane Based on SSR and AFLP Markers

Abstract

To take advantage of the MAS technique and develop the molecular genetic linkage map in sugarcane breeding program in China,we constructed two molecular genetic maps by single dose markers (SDM) and double dose markers (DDM) from 36 SSR and 12 AFLP primers for two mapping populations (F1 and BC1).F1 population was from cross combination of sugarcane commercial variety (Co419) × S.spontaneum (Y75/1/2) consisting of 269 true individuals,BC1 population from backcross combination of F1 02/356×sugarcane commercial variety (ROC25) with 266 true individuals.All plants from two populations were detected by PCR.Two molecular genetic linkage maps were established.298 SDMs and DDMs were acquired by χ2 test from 630 segregation markers of F1 population,about 47% of total markers;264 SDMs and DDMs were obtained from 571 segregation markers of BC1 population which were 46% of total markers,Co41902/356Y75/1/2ROC25 in efficiency of getting SDMs and DDMs.Based on LOD ≥ 5.0,genetic distance ≤ 40 cM between markers,134 of 298 SDMs and DDMs from F1 population formed 55 linkage groups (LGs),among which 39 LGs were included in eight homology groups(HGs),16 LGs were excluded,the map length reached 1 458.3 cM with an average distance of 10.9 cM between markers;133 of 298 SDMs and DDMs from BC1 population made up 47 LGs,among which 34 LGs were composed in eight HGs except for 13 LGs,the map covered 1 059.6 cM with an average distance of 8.0 cM.At the same time,these SDMs and DDMs from Co419 and Y75/1/2 formed 34 LGs and 20 LGs,respectively,and these SDMs from two parents only made up 1 LGs;19 LGs were obtained from these SDMs and DDMs of 02/356,and ROC25,9 LGS were formed by SDMs from two parents;Co419Y75/1/202/356=ROC2 according to forming number of LGs.These results indicated that F1 mapping population was better than BC1 mapping population in quality of constructing linkage map.The maps will provide the valuable information for locating gene,further research on genetic linkage map and MAS breeding.