Segregation for resistance to fusariose, leaf margin type, and leaf colour from the EMBRAPA pineapple hybridization programme

During the hybridization programme for breeding cultivars resistant to fusariose, segregations for resistance, leaf type, and leaf colour were recorded in crosses involving cvs 'Perolera', 'Primavera', 'Roxo de Tefe' 'Guiana', 'Smooth Cayenne', 'Perola', 'Puerto Rico', and Ananas bracteatus 'Sao Bento'. 'Perolera' and 'Primavera: transmitted their fusariose resistance to all their progenies, resulting in a low and normal mortality in artificially-inoculated seedlings. Crosses between susceptible 'Guiana' and 'Perolera' produced entirely susceptible progenies showing very low survival rates at the end of the test. These results suggest a simple genetic mechanism, probably a single gene with dominance. Segregations for leaf types were in accordance with frequencies expected from the bigenic model of Collins and Kerns. 'Primavera' is homozygous for the 'piping' leaf type. Segregations for leaf colour as studied in crosses involving the red-leaved 'Rojo de Tefe' indicated a dominant monogenic inheritance of the dark red leaf type. Simple dominant inheritance of the three traits opens good prospects for the creation of smooth and attractive resistant cultivars.