TY - BK AU - Machado,N.G. AU - Kholi,M.M.|Martino,D. ED - Centro Internacional de Mejoramiento de Maiz y Trigo (CIMMYT), Mexico DF (Mexico) TI - Trigo híbrido: una experiencia comercial SN - 9974-7586-0-2 U1 - 633.1158 PY - 1998/// CY - La Estanzuela (Uruguay) PB - INIA|CIMMYT KW - Combining ability KW - Crop management KW - AGROVOC KW - Crossbreeding KW - Germplasm KW - Research projects KW - Selection KW - Variety trials KW - Genetic resources KW - Wheat KW - Yields KW - Hybrids KW - CIMMYT KW - INIA N2 - Hybrid wheat program based on the male sterility system of Triticum timopheevi was developed in Argentina since 1970. The program resulted in identification of commercial products that allowed massive diffusion in 1990, reaching a total of 157 000 bags of seed of 40 kg each.||Pedigree selection method was modified that permitted an advance in the characters related with cross-fertilization, genes for restoration and combining ability. Two separate crossing blocks (for line B and line R) were developed utilizing the winter wheat germplasm from USA and Europe and the spring wheat germplasm from Argentina and CIMMYT. The use of advanced lines in combinations imply a lengthy and difficult process due to the need of a backcross system for the B lines and the selection of complete expression of restorers. Only at this stage, the combining ability of each line was identified. The commercial production of hybrids was successful not only because of the good combining ability of the lines utilized, but also because of the precise knowledge regarding their flowering habit and capacity to produce or receive pollen. The climatic conditions in the wheat sub-region IV of Argentina are optimum that allow cross fertilization due to moderate temperatures, high humidity and constant winds.||Non technical reasons were responsible for the interruption in the production of hybrid wheat program. However, experience indicates that it is a genetic resource, important to be taken into account, in those regions that provide crop production conditions similar to those described above. The availability of chemical gametocides and more efficient genetic systems will further increase the possibilities of a successful hybrid wheat program in the future ER -