caa a22 4500 445323760 CHVBK 20180317142713.0 cr unu---uuuuu 170323e20110301xx s 000 0 eng 10.1007/s10681-010-0272-2 doi (NATIONALLICENCE)springer-10.1007/s10681-010-0272-2 Rapid and high-precision marker assisted backcrossing to introgress the SUB1 QTL into BR11, the rainfed lowland rice mega variety of Bangladesh [Elektronische Daten] [K. Iftekharuddaula, M. Newaz, M. Salam, H. Ahmed, M. Mahbub, E. Septiningsih, B. Collard, D. Sanchez, A. Pamplona, D. Mackill] Flooding is one of the major hazards of rice production for the rainfed lowland rice ecosystem, and tolerant cultivars are urgently needed to help protect farmers from submergence damage. A quick and efficient strategy was implemented to introgress SUB1, a major QTL for submergence tolerance, into a rainfed lowland mega variety BR11 of Bangladesh by only two backcrosses and one selfing generation. In marker-assisted backcrossing (MABC), one tightly-linked simple sequence repeat (SSR) and two gene-based markers, four flanking SSR and 116 background SSR markers were used for foreground, recombinant and background selection, respectively, in backcrosses between a SUB1 donor IR40931-33-1-3-2 and BR11. BR11-Sub1, identified in a BC2F2 plant, possessed BR11 type SSR alleles on all fragments analyzed except the SUB1 QTL. The introgression size in BR11-Sub1 was 800Kb indicating approximately 99.8% identity to BR11. BR11-Sub1 along with other introgression lines showed submergence tolerance similar to the tolerant parent. Yield, yield-component parameters and grain physico-chemical properties showed successful recovery of the BR11 traits in BR11-Sub1, with yield potential ranging from 5.2 to 5.6t/ha, not significantly different from the recurrent parent mega variety BR11. Producing a large number (~1000) of backcross F1 plants was considered essential to achieve recombination on both sides of the gene, limiting linkage drag with only two backcrosses. A large number of background markers ensured proper recovery of the recurrent parent genome in the BC2F2 generation. The study demonstrates a rapid and highly precise strategy to introgress a major QTL by BC2F2 generation into a modern rice variety using an unadapted donor. The variety can replace BR11 on more than 2million of ha in Bangladesh and provide major increases in rice production. Springer Science+Business Media B.V., 2010 Marker Assisted Backcrossing (MABC) nationallicence SUB1 QTL nationallicence Variety BR11 nationallicence Rainfed lowland rice nationallicence Submergence tolerance nationallicence Iftekharuddaula K. Bangladesh Rice Research Institute, 1701, Gazipur, Bangladesh aut Newaz M. Bangladesh Agricultural University, 2202, Mymensingh, Bangladesh aut Salam M. Bangladesh Rice Research Institute, 1701, Gazipur, Bangladesh aut Ahmed H. Bangladesh Rice Research Institute, 1701, Gazipur, Bangladesh aut Mahbub M. Bangladesh Rice Research Institute, 1701, Gazipur, Bangladesh aut Septiningsih E. International Rice Research Institute, DAPO Box 7777, Metro Manila, Philippines aut Collard B. NSW Department of Primary Industries, 2340, Tamworth, NSW, Australia aut Sanchez D. International Rice Research Institute, DAPO Box 7777, Metro Manila, Philippines aut Pamplona A. International Rice Research Institute, DAPO Box 7777, Metro Manila, Philippines aut Mackill D. International Rice Research Institute, DAPO Box 7777, Metro Manila, Philippines aut Euphytica Springer Netherlands 178/1(2011-03-01), 83-97 0014-2336 178:1<83 2011 178 10681 https://doi.org/10.1007/s10681-010-0272-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10681-010-0272-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Iftekharuddaula K. Bangladesh Rice Research Institute, 1701, Gazipur, Bangladesh aut NATIONALLICENCE 700 1- Newaz M. Bangladesh Agricultural University, 2202, Mymensingh, Bangladesh aut NATIONALLICENCE 700 1- Salam M. Bangladesh Rice Research Institute, 1701, Gazipur, Bangladesh aut NATIONALLICENCE 700 1- Ahmed H. Bangladesh Rice Research Institute, 1701, Gazipur, Bangladesh aut NATIONALLICENCE 700 1- Mahbub M. Bangladesh Rice Research Institute, 1701, Gazipur, Bangladesh aut NATIONALLICENCE 700 1- Septiningsih E. International Rice Research Institute, DAPO Box 7777, Metro Manila, Philippines aut NATIONALLICENCE 700 1- Collard B. NSW Department of Primary Industries, 2340, Tamworth, NSW, Australia aut NATIONALLICENCE 700 1- Sanchez D. International Rice Research Institute, DAPO Box 7777, Metro Manila, Philippines aut NATIONALLICENCE 700 1- Pamplona A. International Rice Research Institute, DAPO Box 7777, Metro Manila, Philippines aut NATIONALLICENCE 700 1- Mackill D. International Rice Research Institute, DAPO Box 7777, Metro Manila, Philippines aut NATIONALLICENCE 773 0- Euphytica Springer Netherlands 178/1(2011-03-01), 83-97 0014-2336 178:1<83 2011 178 10681 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer