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020			_a978-1-4020-5496-9
020			_a978-1-4020-5497-6 (Online)
040			_aMX-TxCIM
041			_aeng
090			_aCIS-5062
100	1		_aKOHLI, M. M. _95622
245	1	0	_aHistorical cross-site association based on cultivar performance in the Southern Cone
260			_aDordrecht (Netherlands) : _bSpringer, _c2007.
300			_a9 pages
340			_aPrinted
490			_aDevelopments in Plant Breeding ; _vvol. 12
520			_aSouthern Cone wheat growing region is considered one large epidemiological zone separated by the Andes Mountain Range. Although local breeding programs have exchanged germplasm successfully and results have been published regularly, very little effort has been made to determine site similarities based on historical data. The present study uses 12 years of agronomic data on days to heading (DH), leaf rust reaction (LR) and septoria leaf blight infection (SB) from Southern Cone Wheat Advanced Lines Nursery (LACOS) to define and characterize cross-site associations. A modified pattern analysis using classification (cluster analysis) and ordination (Factor analysis) based on distances and similarities (average correlations between sites) were utilized for sites representing at least three years of data for each trait. Two factors accounted for very large proportion (73 percent) of the variation for DH. However, in the cases of LR and SB slightly lower variation, 45.6 and 53.5 percent respectively, was explained by two factors. Using three factors, 68.4 percent of the variation in SB and 53.5 percent of the variation in LR could be explained. Fourteen common sites were used classify the region in two distinct groups with regards to DH. The key factor seems to be the temperature regime during the vegetative phase of the crop in the two regions separated by the parallel 27ˆ South. The higher temperature regime of the north (Bolivia, Brazil and Paraguay) can be further subdivided to include very high temperature sites of Sao Paulo, Brazil, and drought prone site, San Benito, Bolivia, in one subgroup separating it from other sites in this group. Lower temperature locations grouped together represent sites in Argentina, Chile and Uruguay. LR represented a large variation in grouping the sites together. While all sites in Brazil grouped together as a unit, explaining the virulence similarity in this country, two Chilean sites, La Platina and Chillan grouped independently. Surprisingly, Chillan grouped with locations in Argentina. The fourth group includes sites in Paraguay, Uruguay and Mexico; all of them with heavy infection ratings over the years. Similar variation was observed in the groupings of seven SB sites. While Toluca, Mexico, and Marcos Jùarez, Argentina, represented two independent groups, highland sites of Patzcuaro, Mexico, and Escalante, Bolivia, made up the third group. The southern locations of Chillan, Chile, and La Estanzuela, Uruguay, represented the high infection sites as an independent group. The site similarities demonstrated in this study should increase our understanding of the variation present in the Southern Cone Wheat Region and enhance cultivar adaptation across programs
536			_aGenetic Resources Program
546			_aTest in English
594			_aCCJL01
595			_aCSC
650		7	_2AGROVOC _91303 _aVarieties
650		7	_2AGROVOC _95609 _aSeptoria
650		7	_2AGROVOC _91251 _aRusts
650		7	_2AGROVOC _91310 _aWheat
700	1		_aCrossa, J. _gGenetic Resources Program _8CCJL01 _959
700	1		_aFranco, J. _8CFRN01 _gFormerly Genetic Resources Program _9494
773			_dDordrecht (Netherlands) : Springer, 2007. _gp. 761–769 _tWheat Production in Stressed Environments _wG89985 _z978-1-4020-5496-9
942			_cBP _2ddc
999			_c10232 _d10232