Marker-assisted backcross breeding to combine multiple rust resistance in wheat

摘要

A widely grown but rust susceptible Indian wheat variety HD2932 was improved for multiple rust resistance by marker-assisted transfer of genes Lr19, Sr26 and Yr10. Foreground and background selection processes were practised to transfer targeted genes with the recovery of the genome of HD2932. The near-isogenic lines (NILs) of HD2932 carrying Lr19, Sr26 and Yr10 were individually produced from two backcrosses with recurrent parent HD2932. Marker-assisted background selection of NILs with 94.38-98.46% of the HD2932 genome facilitated rapid recovery of NILs carrying Lr19, Sr26 and Yr10. In the BC2F2 generation, NILs were intercrossed and two gene combinations of Lr19+Yr10, Sr26 + Yr10 and Lr19+Sr26 were produced. A total of 16 progeny of two gene combinations of homozygous NILs of HD2932 have been produced, which are under seed increase for facilitating the replacement of the susceptible HD2932 with three of the sixteen improved backcross lines with resistance to multiple rusts.