【作者】 周莉花；

【导师】 郝日明；

【作者基本信息】 南京农业大学 ， 园林植物与观赏园艺， 2004， 硕士

【摘要】 蜡梅Chimonanthus praecox(L.)Link为蜡梅科Calycanthaceae蜡梅属植物，冬季开花，与绝大多数春季至秋季开花植物相比，其传粉时间和过程具有一定的特殊性。本文首次以南京地区引种的处于半自然状态的蜡梅为对象进行蜡梅传粉生物学研究。试验分别在2002-2003年和2003-2004年冬季进行，研究内容包括：花期物候观察、花部形态观察和统计、雌雄配子体功能测定、访问昆虫种类、访问行为、访花频率和效率；同时对蜡梅繁育系统进行了检测，检测内容包括花粉胚珠比(P/0)、杂交指数(OCI)及不同处理花粉萌发率及结实率检测等等，同时还进行了蜡梅与亮叶蜡梅传粉过程比较。 实验结果表明：(1)蜡梅变异主要存在于花部性状，这些性状包括内被片颜色、中被片颜色和形状、雌雄蕊数目、雌雄蕊变异、花型、花径等，在南京地区，蜡梅的花期从11月到翌年3月，主要集中在12月到翌年2月之间，早花期品种和晚花品种较少。而亮叶蜡梅的花部性状相对单一，在南京地区的花期从9月到12月之间。蜡梅吸引昆虫的主要对策是花繁、香气，给访问昆虫的报酬是内被片分泌的蜜汁及花粉。(2)不同品种蜡梅的花粉活力存在明显区别，室温条件下花粉活力能保持15-20d，冷藏条件下(4±2℃)能保存2个月左右；柱头的可受期约5d。蜡梅与亮叶蜡梅尽管存在雌雄异熟现象，但同朵花内的雌、雄蕊的功能在时间上可遇，有效可遇期分别为2d和0.5d。(3)蜡梅P/0值为2847.3±1125.0、OCI累计分值等于3，与不同处理的花粉萌发率和结实率的结果一样，都显示蜡梅繁育系统为兼性异交类型；亮叶蜡梅繁育系统同蜡梅相似，但亮叶蜡梅的自交比例相对较高．(4)荧光镜检结果显示，蜡梅花粉落置到柱头上20h后开始萌发，落置柱头上的花粉多数可以萌发，但只有1-2根花粉管在第五天左右可以穿越子房，到达珠孔端，再从珠孔端进入胚囊母细胞完成受精，其花粉管生长方式是以胼胝塞的形式往前推进。(5)南京地区蜡梅的访问昆虫约16种，分属膜翅目Hymenoptera、双翅目Diptera、鞘翅目Coleoptera，缨翅目Thysanoptera、及蛛形纲Arachnoidea，主要传粉昆虫有4种：膜翅目蜜蜂科东方蜜蜂中华亚种Apis cerana cerana Fabricius、双翅目蝇科Muscidae黑边家蝇Musca herveiVillcneuve、丽蝇科Calliphoridae巨尾阿丽蝇Aldrichina grahami(Aldrich)及食蚜蝇科Syrphidae黑带食蚜蝇Epistrophe balteata De Geer；亮叶蜡梅的访问昆虫约18种，分属鞘翅目Coleoptera、半翅目Hemiptera、缨翅目Thysanoptera、膜翅目Hymenoptera、双翅目Diptera、鳞翅目Lepidoptera，另外有蛛形纲Arachnoidea的蜡橄Ch俪ononthus pr口ecox(L .) Link)的传粉生物学研究蜘蛛，主要传粉昆虫为鞘翅目的蓝色九节跳甲入乞刀少伪朋。叨℃二Baly、龟纹飘甲介明咖印少弓扣”l’ca(Th unbe回、露尾甲科Nitiduidae一种和半翅目的长蜷Lygae记ae昆虫，从传粉昆虫看，蜡梅比亮叶蜡梅进化.昆虫访问蜡梅出现在最高气温超过10℃的晴朗天气，一天中昆虫访问时间有限，出现在10: 00一14:的之间，12:00一13:。O为昆虫活动高峰.(6)在静风条件下，风媒对两种植物的传粉作用均可忽略不计.更多还原

【Abstract】 C. praecox(L.) Link (Calycanthaceae), is a deciduous shrub or small tree, and an endemic plant of China. Compared with other species whose florescence is earlier than its, blooming in winter, C.praecox is special in its pollination time and process. This paper firstly focused on and evaluated the pollination characteristics of C. praecox, in half-natural habitat of Nanjing. We investigated flowering phenology, flowering patten, pollen viability, stigma receptibility, species of visitors, visiting rate of visitors and their foraging behavior. And we also investigated its breeding system, including pollen-ovule ratio(P/0), out-crossing index(OCI), pollen grains deposited in stigmas, pollen germination rate and seed set rate with different treatments, from 2002 to 2004. We compared the pollination characteristics of C. praecox and that of C.nitens.The results are as follows:(1) The main variation of C.praecox exists in the floral morphological characteristics, including the variation of the color of the interior perianth segments, the color and shape of the middle perianth segments, the number of pistils and stamens, the length of pistils and degradation of stamens, the floral shape and size, etc.. C. praecox’s florescence is from November to next March, mainly from December to next February. The floral characteristics of C. nitens are less varied, and its florescence is from September to December in Nanjing. A great number of and sweet scent of flower of C. praecox are attractants, and pollen grains and nectar of it are rewards to vistors.(2) Pollen viability of different varieties of C.praecox are distinctly different. The life-span of pollen is 15 to 20 days under room condition and 2 months under 4+2C; The life-span of receptive stigmas is 5 days. In spite of protogyny, the meeting time of life of effective pollen and stigma of two species are respectively 2 days and 0. 5 day.(3) The value of P/0 of C.praecox is 2847.3+1125.0, and the total value of OCI is 3. With the above results, pollen germination rate and seed set rate, all shows that breeding system of C. praecox is facultative hybridization. Thebreeding system of C.nitens is similar to C.praecox, but it is higher in proportion of self-pollination than that of C. praecox.(4) Fluorescent investigation shows that pollen started to germinate about 20 hours later after deposited on the stigmas, only 1 or 2 pollen tubes can penetrate ovary to micropylar end on the fifth day. Callose plugs evenly formed in the pollen tube, and sometimes callus deposited randomly along pollen tube wall and even the whole tube wall.(5) 16 species of insects visited C.praecox in Nanjing, belonging to Hymenoptera,Diptera, Coleoptera, Thysanoptera and spiders(Arachnoidea); Apis cerana cerana Fabricius,Aldrichina grahami(Aldrich),Epistrophe balteata De Gee, Musca hervei Villeneuve are its main efficient pollinators. The main visiting insects of C. nitens in Nanjng are beetles. Because Beetles originated earlier than Bees and Flies, so in this aspect C.praecox is more evolutional than C.nitens. Insects visited C.praecox only in the sunny days and when the highest temperature of day is higher than 10C, their visiting time is from 10:00 to 14:00 in a day, and its peak is from 12:00 to 13:00.(6) The effect of wind to spreading pollens of both species is little.更多还原