Floral ontogeny of Pedicularis （Orobanchaceae）, with an emphasis on the corolla upper lip  

作　　者：Wen-Bin YU Jie CAI De-Zhu LI Robert R. MILL Hong WANG 

机构地区：[1]Key Laboratory of Biodiversity and Biogeography, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China [2]Department of Botany, Field Museum of Natural History, Chicago IL 60605, USA [3]Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China [4]Royal Botanic Garden Edinburgh, Edinburgh EH3 5LR, UK

出　　处：《Journal of Systematics and Evolution》2013年第4期435-450,共16页植物分类学报（英文版）

基　　金：Acknowledgements This study was supported by the National Natural Science Foundation of China （Grant Nos. 30970201, 30570115, 31200185）, the National Basic Research Program of China （973 Program, Grant No. 2007CB411600）, and the West Light Foundation of the Chinese Academy of Sciences. The Royal Botanic Garden Edinburgh was supported by the Scottish Government＇s Rural and Environment Science and Analytical Services Division. The authors thank Prof. H.-X. Liang for her expertise with experiments in the laboratory, and four anonymous reviewers and Prof. ~. Ren for their helpful comments and suggestions on the manuscript.

摘　　要：Pedicularis shows high diversity in its corolla form, however, its floral ontogeny has been rarely investigated. In particular, the development of the highly variable upper lip （galea）, three broad morphological types of which （beakless and toothless, beakless and toothed, beaked） can be discriminated, remains unknown. We used scanning electron microscopy to investigate the early stages of floral ontogeny in two beaked species, Pedicularis gruina and P. siphonantha. To compare the developmental processes of the three galea types, three species for each type were investigated. Initiations of floral organs in Pedicularis are consistent. Sepal initiations are successive from the lateral-adaxial primordia, followed by the lateral-abaxial ones （these sometimes missing）, then the mid-adaxial one （again sometimes missing）. The stamens are initiated prior to the petals, or development of petal primordia may be retarded at the early stages in comparison with that of stamen primordia. Four stamen primordia are initiated simultaneously. The five petal primordia are initiated almost simultaneously. Development processes of the upper lip among the three galea types differ in the expansion rates and directions of the cells of the two lobes and these differences govem whether or not a beak and/or teeth are formed on the upper lip. The floral ontogeny of Pedicularis is close to that of Agalinis, which supports the molecular assignment. Floral monosymmetry of Pedicularis is established at the beginning of sepal initiation and is maintained until flowering. The development of the upper lip provides some clues to the evolution of beaked and/or toothed galeas in Pedicularis.Pedicularis shows high diversity in its corolla form, however, its floral ontogeny has been rarely investigated. In particular, the development of the highly variable upper lip （galea）, three broad morphological types of which （beakless and toothless, beakless and toothed, beaked） can be discriminated, remains unknown. We used scanning electron microscopy to investigate the early stages of floral ontogeny in two beaked species, Pedicularis gruina and P. siphonantha. To compare the developmental processes of the three galea types, three species for each type were investigated. Initiations of floral organs in Pedicularis are consistent. Sepal initiations are successive from the lateral-adaxial primordia, followed by the lateral-abaxial ones （these sometimes missing）, then the mid-adaxial one （again sometimes missing）. The stamens are initiated prior to the petals, or development of petal primordia may be retarded at the early stages in comparison with that of stamen primordia. Four stamen primordia are initiated simultaneously. The five petal primordia are initiated almost simultaneously. Development processes of the upper lip among the three galea types differ in the expansion rates and directions of the cells of the two lobes and these differences govem whether or not a beak and/or teeth are formed on the upper lip. The floral ontogeny of Pedicularis is close to that of Agalinis, which supports the molecular assignment. Floral monosymmetry of Pedicularis is established at the beginning of sepal initiation and is maintained until flowering. The development of the upper lip provides some clues to the evolution of beaked and/or toothed galeas in Pedicularis.

关 键 词：corolla upper lip development of monosymmetry floral diversity floral evolution galea OROBANCHACEAE PEDICULARIS rostrum （beak） Scrophulariaceae. 

分 类 号：S688.4[农业科学—观赏园艺] Q959.223.5[农业科学—园艺学]