The existence of several major genetic factors affecting important agronomic characteristics has led the coffee breeders to use them in their breeding program. The gene Ct (reduced growth) and xc (yellow pericarp and better out-turn) have been used rather extensively in an attempt to reduce the height of the 'Bourbon Amarelo' and improve the out-turn of the 'Mundo Novo' cultivars. Some data of a series of hybrids between 'Bourbon Amarelo', 'Caturra Amarelo', 'Caturra Vermelho', 'Bourbon Vermelho' and 'Mundo Novo' are discussed in the present paper. As expected, due to the origin of these cultivars, the F2 generation showed little genetic variation. Some of the new recombinants carrying the desirable major genetic factors, were shown to be inferior to the cultivar 'Mundo Novo'. The most promising combination was selected from the cross 'Bourbon Amarelo' x 'Mundo Novo'. Some plants selected from the cross 'Caturra Amarelo' x 'Bourbon Amarelo', although not as productive as 'Mundo Novo', are much shorter. These latter selections, will improve the condition for harvesting operation and will permit the cultivation of the coffee trees with reduced spacing. Crosses between selected plants of the cultivars 'Bourbon Amarelo' and 'Caturra Amarelo' gave rise to progenies with a high proportion of plants producing fruits with empty locules. The coffee plants used in the crosses did not carry the alleles for endosperm abortion. Consequently, this fact may be taken as evidence that the endosperm abortion may be produced by at least a pair of complementary genetic factors. It also indicates that in hybrid populations all plants must be analysed to avoid the selection of those which may carry this defect.