000			03238nab a22003377a 4500
001			G90427
003			MX-TxCIM
005			20230904182928.0
008			210618s2008 at |||p|op||| 00| 0 eng d
022			_a0004-9409
024	8		_ahttps://doi.org/10.1071/AR07223
040			_aMX-TxCIM
041			_aeng
090			_aCIS-5282
100	1		_aLage, J. _920327
245	1	0	_aCIMMYT's use of synthetic hexaploid wheat in breeding for adaptation to rainfed environments globally
260			_aVictoria (Australia) : _bCSIRO Publishing, _c2008.
340			_aComputer File|Printed
500			_aPeer review
520			_aThe International Maize and Wheat Improvement Center (CIMMYT) has had significant impact on wheat production in rainfed regions of the developing world. During the last decade, yield potential has increased in drought-prone areas partly due to the use of synthetic hexaploid wheat (SHW), produced through interspecific hybridisation of Triticum turgidum spp. and Aegilops tauschii, followed by chromosome doubling. The objectives of this study were to document the use of SHW in wheat breeding at CIMMYT and quantify its potential effect on global wheat adaptation. The first SHWderived lines targetted at rainfed conditions appeared in the 5th Semi-Arid Wheat Yield Trial (SAWYT) representing8%of the lines, increasing to 46% by the 15th SAWYT.During the same period the average coefficient of parentage ofSHWin all synthetically derived crosses decreased from 75 to 19%. Average yield rank of genotypes across locations and years was used as a performance indicator of the SHW-derived lines in SAWYT 5–12. In the 5th SAWYT the average rank of the SHW-derived lines was 30 (out of 50) increasing to 25 by the 12th SAWYT.SAWYT11 was the first trial to include SHWderived lines bred exclusively for rainfed environments, using directed selection for drought tolerance. International trial data from SAWYT 11 and 12 showed that the SHW-derived line Vorobey was a top-performing line. Vorobey performed well across all environments compared with the best locally adapted check cultivar at each location; trial means ranged from 1 to 8 t/ha. To further exploit genetic diversity for adaptation to drought, SHW has been produced using emmer wheat (T. turgidum L. subsp. dicoccon) as the tetraploid parent. Yield trial data from Mexico show thatSHWderivatives based on emmerwheat improved yield performance under drought compared with their drought-tolerant recurrent parents. Theuse of SHWin wheat breeding for rainfed environments atCIMMYThas increased significantly over the past 10–15 years and the performance and effect of the derived lines have improved with time.
546			_aText in English
591			_aCSIRO
650	1	0	_91080 _aDrought _2AGROVOC
650		7	_aExperimentation _2AGROVOC _94432
650		7	_aExperimental data _2AGROVOC _914932
650		7	_aWheat _2AGROVOC _91310
700	1		_9341 _aTrethowan, R.M.
773	0		_tAustralian Journal of Agricultural Research _n635180 _gv. 59, no. 5, p. 461-469 _dVictoria (Australia) : CSIRO Publishing, 2008. _wG444170 _x0004-9409
856	4		_yAccess only for CIMMYT Staff _uhttps://hdl.handle.net/20.500.12665/743
942			_cJA _2ddc _n0
999			_c26992 _d26992