| Popis: |
Up till now, pineapple breeding programs based on direct hybridisation have not been efficient in generating new cultivars, The high level of heterozygosity of the cultivars used for hybridisation and the great number of characters evaluated during the selection process have largely contributed to this situation. Heterozygosity can be reduced by selfing the parental varieties to be used for hybridisation. Inflorescences of 'Smooth Cayenne', 'Pérola', 'Perolera', 'Primavera' and 'Roxo de Tefé' were protected before flowering to ensure self-pollination. Seeds obtained were transferred to petri dishes with water agar as substrate, germinated in growth chamber, under 26 to 28°C, 16 hours photoperiod and 1600 lux of light intensity. One hundred and five seedlings were obtained from 'Roxo de Tefé', seven from 'Primavera', two from 'Perolera', two from 'Pérola' and none from 'Smooth Cayenne'. Thirty-one seedlings of 'Roxo de Tefé' were albinos and died after germination. Only 16 out of the 74 remaining seedlings of 'Roxo de Tefé' survived, all of them spiny, as their parent, 12 showing red leaves like the parent and four showing green leaves, thus expressing normal segregation for this monogenic trait. All the seven seedlings obtained from 'Primavera' had spineless green leaves as the parent. Both seedlings obtained from 'Perolera' have green leaves, one of them being spiny and the other spineless, The two seedlings obtained from 'Pérola' resembled their parent but they died during the nursery stage. |
