Abstract The floral morphology and pollination of S. guineense subsp. macrocarpum were investigated on ten trees selected for a study of floral phenophases in the natural forest of Bassila, located in the Sudano-Guinean zone (Benin). For the floral analysis, the two stages considered were flower buds for preflowering data and open flowers for flower data. To determine the pollination mode and identify main pollinators, two stages were considered, namely flower bud and initiated fruits. The fruit set, autogamy and allogamy rate were assessed. Results show that several flower morphological traits predispose this species to selfing and cross pollination, including hermaphroditism and a long anther–stigma distance. The symmetry is actinomorphic with a floral receptacle adnate to the ovary. The latter is inferior, bicarpellary and bilocular syncarpous and contains 18–22 ovules on an axile placenta. Only a single ovule is fertilized and becomes a seed. Visitors frequently registered on the flowers of S. guineense subsp. macrocarpum are exclusively insects belonging to six orders, including Diptera (26%), Hymenoptera (24%), Lepidoptera (19%). The mean fruit set was 0.47 ± 0.10 for the open-pollination experiments and 0.27 ± 0.12 for autogamous self-pollination. The autogamy rate was 57.45% and the allogamy rate 42.55%. This study confirms that S. guineense subsp. macrocarpum is predominantly autogamous. Self-compatibility is not for exceptional species, but a dominant characteristic of the genus Syzygium. The viability of the pollen grains and receptivity of the stigma at each flowering stage should be further studied.

中文翻译：

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Syzygium guineense (Willd.) DC 的花卉形态和授粉系统。亚种 macrocarpum (Engl.) F. White (Myrtaceae)，花蜜产量高的亚种

摘要 S. guineense subsp. 的花形态和授粉。在位于苏丹 - 几内亚地区（贝宁）的巴西拉天然林中，对十棵树进行了研究，以研究花物候期。对于花分析，考虑的两个阶段是花前数据的花蕾和花数据的开放花。为了确定授粉方式和确定主要授粉媒介，考虑了两个阶段，即花芽和果实。评估坐果率、自配性和同种配性率。结果表明，几种花的形态特征使该物种易于自交和异花授粉，包括雌雄同体和长花药柱头距离。对称性是辐射对称的，花托贴在子房上。后者较差，双心和双眼合胞体，在轴胎盘上含有 18-22 个胚珠。只有一个胚珠受精并成为种子。游客经常在 S. guineense subsp. 的花朵上登记。macrocarpum 是属于六目昆虫，包括双翅目（26%）、膜翅目（24%）、鳞翅目（19%）。开放授粉实验的平均坐果率为 0.47 ± 0.10，自花授粉实验的平均坐果率为 0.27 ± 0.12。自婚率为57.45%，同婚率为42.55%。这项研究证实了 S. guineense subsp。macrocarpum 主要是自交的。自交性不是特殊物种，而是 Syzygium 属的主要特征。应进一步研究花粉粒的活力和柱头在每个开花阶段的接受能力。