通过野外观察和实验室检测，研究了广西南宁市的灰木莲的花部结构、开花物候、花粉活力、访花者行为，用杂交指数（ OCI）、花粉／胚珠比（ P／O）及去瓣、去雄、套袋、人工授粉等方法测定了其繁育系统。结果表明，灰木莲群体在3月下旬－5月下旬开花，个体开花持续时间约28天，相对开花强度主要分布范围是30％～60％，开花的同步性指数达0．735，属于集中开花模式；灰木莲两性花为雌雄蕊异熟类型，同花雌蕊先成熟，失去授粉机能后雄蕊花药才裂开散粉；灰木莲花粉粒的生活力超过60％；花粉／胚珠比为953．2，杂交指数为4，表明灰木莲繁育系统属于异交为主，部分自交，需要传粉昆虫才能完成其繁殖；自然状态下灰木莲无结实，人工授粉后结实率为20％～30％；在灰木莲中未发现有访花昆虫，只有花蓟马在花中活动，而且未能形成有效的传粉。传粉者的缺乏可能是导致灰木莲在南宁市不能自然结实的主要原因。%The floral morphology and flowering characteristics of Manglietia glauca in Nanning were studied by field observations and laboratory detection , and breeding system was investigated by out-crossing index ( OCI ) , pollen-ovule ratio ( P/O ) , petals-removed , emasculated , bagged and artificial pollination experiment . The re-sults showed that the flowering span of M.glauca population was from early March to late May , the flowering dura-tion of individual was approximately 28 days, the relative flowering intensity distributed from 30 %~60 %, the flowering synchrony index was 0.735 and exhibited a so-called “mass-flowering pattern”; M.glauca was hermaph-rodite flower and dichogamy type , protogyny was the form of dichogamy , the another dehiscence and pollen release only after the stigmas lost pollination function; The viability of pollen was above 60 %, the P/O was 953.2 and OCI was 4 , and the results indicated that the breeding system of M.glauca was belonged to out-crossing with partly self-compatibility , and pollinator insects were essential .; M.glauca was sterile at natural conditions and setting rates were 20 %~30 % in artificial pollination experiment; It was not found that any flower-visiting insects in M.glauca.Frankliniella intonsa was the only insect on flowers and it could not make an effective pollination .Lack of pollinators might be the main reasons that M.glauca was unable to seed under natural conditions in Nanning .
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