不同生境下陌上菜的形态解剖学比较

Comparative study of the morphological and anatomical features of Lindernia procumbens in different ecological environments(Linderniaceae)

本研究首次采用GMA切片等方法对不同生境下陌上菜的形态结构进行了深入的研究。结果显示,陌上菜种苗发育具有水生植物的特征:种子及种苗需浸水萌发及发育,具下胚轴毛,胚根发育迟缓。成株的营养器官兼具水生及陆生植物的结构特征:完全陆生的植株和湿生植株的气生部位具有较厚角质层,发达的机械组织及较发达的通气组织。完全水生的植株和湿生植株浸水部位的角质层和机械组织不发达,但通气组织非常发达。生殖器官:完全陆生和湿生的植株具有闭锁和开放2种类型的花,而完全水生的植株仅具闭锁花,从而保证了这一物种在不同生境下均能正常结实。此外,陌上菜具有特立中央胎座。本研究首次揭示了陌上菜在不同生境下种苗发育、营养器官及生殖器官结构的变化,完善了陌上菜的形态学,为进一步研究母草科的系统学提供了形态学依据。

The morphology and anato for the first time. The results show my of Lindernia procumbens were deepl the seedling development of the species y studied using the GMA method has the characteristics of aquatic plants, the seed and seedling submerged in water could germinate and develop, the hypocotyl hairs occur on the collet, the radicle development is retardate. The vegetative organ of the mature plant of the species has the characteristics which occur in terrestrial plants and aquatic： the terrestrial plant and aerial parts of the hygroph- ilous plant have thick cuticule, developed mechanical tissues and aerenchymaes. However, the submerged plants and submerged parts of hygrophilous plants are with the undeveloped mechanical tissues and cutieule, very developed aerenchymaes. The reproductive organs： L. procumbens has two types of flowers, chasmoga- mous and cleistogamous. Both occur in the terrestrial and the hygrophilous plants, but the submerged plants only have cleistogamous flowers, which make the species could produce seeds normally. In addition, the spe- cies has a free central placenta. This study show the variation in shapes and structures （including seeding devel- opment, vegetative and reproductive organs of L. procumbens） in the different ecological environments for the first time, perfecting the morphological study and providing the morphological evidence for the systematic study of the family Linderniaceae.