植物花粉与雌蕊结合方式的扫描电镜观察
贾维宸# ，王 宇#，董鹏媛，董春霞，龙 玉，刘轶群*，孟世勇*
（北京大学生命科学学院，北京 100871）
摘 要 近年来，对于被子植物花粉、柱头演化趋势的研究取得了一定突破，但是花粉与柱头在生殖过程中是否存在特定的结合方式尚不明确。本研究使用扫描电子显微镜观察了忍冬科、柳叶菜科和蔷薇科等12科共21种被子植物花粉与雌蕊的结合方式。根据观察的结果，本研究将花粉与雌蕊结合方式归为嵌入式、开口式、覆盖式和攀附式，并进一步提出了这些结合方式的分类标准。这些结合方式在科内具有一定的保守性和特异性，按照演化顺序排序为覆盖式、攀附式、嵌入式、开口式。本研究加深了对被子植物生殖过程的理解，为植物生殖生物学和系统发育学研究提供了新的视角和参考。
关键词 花粉；雌蕊；扫描电子显微镜；花粉管；超微结构
中图分类号：Q945.6+2；Q945.6+3；Q945.53；Q336 Doi:10.3969/j.issn.1000-6281.2025.02.009
Scanning electron microscope observation on the binding mode of plant pollen and pistil
JIA Weichen#, WANG Yu#, DONG Pengyuan, DONG Chunxia, LONG Yu, LIU Yiqun*, MENG Shiyong*
(School of Life Sciences, Peking University, Beijing 100871, China)
Abstract In recent years, significant breakthroughs have been made in understanding the evolutionary trends of pollen and stigma in angiosperms. However, the specific combination patterns between pollen and stigma during reproduction remain unclear. Using scanning electron microscopy (SEM), we captured images of pistil and pollen from 21 plant species across 12 families, including Caprifoliaceae, Onagraceae, and Rosaceae. Our investigation focused on the combination patterns between pollen and pistil in angiosperms. Based on our observations, we classified these patterns into four categories: embedded, opening, covering and climbing, and further proposed classification criteria for these patterns. These combination patterns exhibit a degree of conservativity and specificity within families, showing an evolutionary trend from covering to climbing, embedded, and opening. This study enhances the understanding of reproduction in angiosperms, providing new perspectives and data for research in plant reproduction and phylogenetics.
Keywords pollen; pistil; electron microscopy; pollen tube; microstructure
[1] HESLOP-HARRISON J, HESLOP-HARRISON Y. Surfaces and secretions in the pollen-stigma interaction: A brief review[J]. J Cell Sci Suppl，1985, 2:287-300.
[2] EDLUND A F, SWANSON R, PREUSS D. Pollen and stigma structure and function: The role of diversity in pollination[J]. Plant Cell, 2004,16 Suppl (Suppl): S84-97.
[3] STEAD A D, ROBERTS I N, Dickinson H G. Pollen-pistil interaction in Brassica oleracea: Events prior to pollen germination[J]. Planta, 1979, 146(2):211-216.
[4] ZINKL G M, ZWIEBEL B I, GRIER D G, et al. Pollen-stigma adhesion in Arabidopsis: a species-specific interaction mediated by lipophilic molecules in the pollen exine[J]. Development, 1999,126(23):5431-5440.
[5] WHEELER M J, FRANKLIN-TONG V E, FRANKLIN F C H. The molecular and genetic basis of pollen-pistil interactions[J]. New Phytol, 2001, 151(3):565-584.
[6] DIXIT R, RIZZO C, NASRALLAH M, et al. The brassica MIP-MOD gene encodes a functional water channel that is expressed in the stigma epidermis[J]. Plant Mol Biol, 2001, 45(1):51-62.
[7] LORD E M. Adhesion and guidance in compatible pollination[J]. J Exp Bot, 2003, 54(380):47-54.
[8] LUU D T, HEIZMANN P, DUMAS C. Pollen-stigma adhesion in kale is not dependent on the self-(in)compatibility genotype[J]. Plant Physiol, 1997, 115(3):1221-1230.
[9] NASRALLAH J B, STEIN J C, KANDASAMY M K, et al. Signaling the arrest of pollen tube development in self-incompatible plants[J]. Science, 1994, 266(5190):1505-1508.
[10] ROBICHAUX K J, WALLACE I S. Signaling at physical barriers during pollen-pistil interactions[J/OL]. Int J Mol Sci, 2021, 22(22):12230.
[11] ALLEN A M, THOROGOOD C J, HEGARTY M J, et al. Pollen-pistil interactions and self-incompatibility in the Asteraceae: New insights from studies of Senecio squalidus (Oxford ragwort) [J]. Ann Bot, 2011, 108(4):687-698.
[12] SILVA N F, GORING D R. Mechanisms of self-incompatibility in flowering plants[J]. Cell Mol Life Sci, 2001, 58(14):1988-2007.
[13] ZHANG X, JIA Y, LIU Y, et al. Challenges and perspectives in the study of self-incompatibility in Orchids[J/OL]. Int J Mol Sci, 2021, 22(23):12901.
[14] NASRALLAH J B. Self-incompatibility in the Brassicaceae: Regulation and mechanism of self-recognition[J]. Curr Top Dev Biol, 2019, 131:435-452.
[15] EAVES D J, FLORES-ORTIZ C, HAQUE T, et al. Self-incompatibility in Papaver: advances in integrating the signalling network[J]. Biochem Soc Trans, 2014, 42(2):370-376. [16] HESLOP-HARRISON Y. Stigma characteristics and angiosperm taxonomy[J]. Nord J Bot, 1981, 1: 401-420.
[17] PAUL P, DHAR S, DAS D, et al. Light and scanning electron microscopic characterization of pollen grains of some wetland angiosperms from India[J]. Microsc Res Tech, 2022, 85(7):2628-2650.
[18] ROBINSON R, SOLLAPURA V, COUROUX P, et al. The Brassica mature pollen and stigma proteomes: Preparing to meet[J]. Plant J, 2021, 107(5):1546-1568.
[19] ETTORE P, GIAN G F. Pollen biodiversity – Why are pollen grains different despite having the same function? A review[J]. Botanical Journal of the Linnean Society, 2020, 20:1–24.
[20] HOWE H F, MIRITI M N. When seed dispersal matters[J]. BioScience, 2004, 54(7):651-660. [21] DOMINGOS M A, ALBUQUERQUE L. Bat pollination in the Caatinga: A review of studies and peculiarities of the system in the new world's largest and most diverse seasonally dry tropical forest[J]. Flora, 2023, 305:152-332. [22] SANTANA S E, KALISZEWSKA Z A, LEISER-M L B, et al. Fruit odorants mediate co-specialization in a multispecies plant–animal mutualism[J]. Proc R Soc, 2021, 288:20210312.
[23] BECK C B. 被子植物的起源和早期演化[M]. 北京：科学出版社，1981:190-194.
[24] 杨梅花，郑新开，刘升学，等. 4种睡莲形态的扫描电镜观察[J]. 电子显微学报，2022, 1(41):61-65.
[25] YANG Z Q, ZHANG D Y, BAI W N. The functional significance of a stigma color polymorphism in Acer pictum subsp. mono (Aceraceae)[J]. Journal of Plant Ecology, 2015, 8(2):166-172
