摘要
本文对国产杜英科3属28种的花粉形态进行了光学显微镜观察,并对其中15种进行了扫描电镜观察。观察结果表明杜英科花粉属于小型花粉,3孔沟,沟达极区,内孔横长,在光学显微镜下外壁光滑,外壁内外层分层不明显,两层近相等,3属很难区分;在扫描电镜下,杜英属花粉外壁纹饰分为颗粒状、皱网状和穴状或穴网状三种类型,猴欢喜属花粉外壁纹饰仅有皱网状一种类型,两届难以区别;而文丁果届具有明显的网状纹饰,与另外两属有明显区别。在本科中花粉演化趋势之一可能是向体积增大的方向进行。在花粉形态上与椴树科区别明显,支持将杜共科作为独立的科。同时,花粉形态特征还显示了与大风子科、红树科等的部分相似性。
Pollen grains of the family Elaeocarpaceae in China have been examined under LM and SEM. The results show that the different sizes of the pollen grains of the family range from 9μn to 15μm, 3 -colporate, os lalongate, under LM exine psilate and the stratification of exine is faint. The pollen morphologic characteristics of the family are so similar that the genera Elaeocarpus, Sloanea and Muntingia cannot be distinguished under LM. Under SEM, the genus Elaeocarpus is of three types of exine ornamentation and that of Sloanea is nearly the same as one type of Elaeocarpus, therefore the two genera cannot be distinguished even under SEM. Muntingia can be telled from the other two genera by its exine ornamentation but the difference among Muntingia and other two genera is not strong. The results above suggest that the members in the family be a rather natural group and should be treated as a distinct family rather than parts of the family Tiliaceae. The size and the exine ornamentation of the family are much different from those of other families in the order Malvales. The results also show some affinities with Rhizophoraceae and Flacourtiaceae. On the basis of the pollen morphology, it is agreed with the suggestion that the family is somewhat isolated in the order from the view point of anatomy. Finally it is suggested that one of the tendencies of pollen evolution in the family and the order is probably getting larger size.
出处
《云南植物研究》
CSCD
1990年第4期397-403,共7页
Acta Botanica Yunnanica
关键词
杜英科
花粉形态
Pollen morphology
Elaeocarpaceae
Affinity
