Floral differentiation and development in Carica papaya cultivar ‘Sunrise Solo’

Abstract Under South African subtropical conditions, flower development in the cultivar ‘Sunrise Solo’ of papaya ( Carica papaya ) extended over 10 weeks from emergence to anthesis. Ovary differentiation started 8 weeks before anthesis in female flowers and 6–7 weeks before anthesis in hermaphrodite flowers, and in both cases was complete during the last week before anthesis. Stamen differentation in hermaphrodite flowers began 9 weeks before anthesis and was complete 4 weeks later. Only 1.5 leaves per week developed compared with the 2.2 leaves per week under tropical Hawaiian conditions. Thus, fewer fruits develop during a season in South Africa than during the same time period in Hawaii.