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Fruit growing in the tropics - Part 7

7.1 Pollination and fruit set Flowering habit Without flowers there will be no fruit. Only pistillate (= female) flowers set fruit. Staminate (= male) flowers produce the pollen needed to pollinate pistillate flowers. Perfect (= hermaphrodite) flowers have both pistils and stamens. Figure 17 shows the parts of a perfect flower. | 7 Pollination and fruit set 7.1 Flowering habit Without flowers there will be no fruit. Only pistillate female flowers set fruit. Staminate male flowers produce the pollen needed to pollinate pistillate flowers. Perfect hermaphrodite flowers have both pistils and stamens. Figure 17 shows the parts of a perfect flower. Figure 17 The flower and its parts Flowers borne singly or in small inflorescences as in soursop suga-rapple guava are usually perfect but inflorescences with many flowers like those in mango and rambutan often contain imperfect flowers as well. Strict segregation of the sexes is found in papaya for instance male and female inflorescences are on separate plants. This segregation of the sexes on separate trees which prevents selfpollination is called dioecy. Jackfruit and breadfruit are examples of male and female inflorescences borne on the same tree monoecy . Pollination and fruit set 55 In banana and coconut flowers of both sexes are found in the same inflorescence the staminate flowers at the tip and the pistillate flowers at the base. The large mango inflorescence bears both staminate and perfect flowers. The flowering habit of the fruit crops in this Agrodok is presented in the Appendix. Flowering habits are rather varied. There are for instance papaya cultivars in which all the plants bear fruit because they are either female-flowering or bear perfect flowers. You can recognise these cultivars because the perfect flowers are on long stalks like those of male plants and the fruit is more elongated. Flowering habit not only varies depending on the cultivar it also varies from year to year. The percentage pistillate flowers in coconut or that of perfect flowers in mango may be much higher in one year than in another generally it is higher when growing conditions have been favourable. Growing conditions also influence flower quality. A healthy tree of moderate vigour bears strong flowers the stigma being receptive for pollination over a longer .