植物学报 ›› 2007, Vol. 24 ›› Issue (03): 414-424.

所属专题: 生殖生物学专辑 (2007年24卷3期)

• 特邀综述 • 上一篇    下一篇

荒漠植物种子粘液的生态学意义

刘晓风 谭敦炎   

  1. 新疆农业大学林学院, 乌鲁木齐 830052
  • 收稿日期:2007-02-12 修回日期:2007-03-06 出版日期:2007-05-01 发布日期:2007-05-01
  • 通讯作者: 谭敦炎

Ecological Significance of Seed Mucilage in Desert Plants

Xiaofeng Liu, Dunyan Tan   

  1. College of Forestry, Xinjiang Agricultural University, Urumqi, 830052, China
  • Received:2007-02-12 Revised:2007-03-06 Online:2007-05-01 Published:2007-05-01
  • Contact: Dunyan Tan

摘要: 种子粘液是在种皮外层细胞的高尔基体内产生并分泌到胞腔内或细胞壁层的吸湿膨胀的一类果胶类多糖物质。具粘液种子的植物大多生长在荒漠地区, 广泛存在于十字花科、菊科和车前科等类群中。粘液的存在对荒漠植物种子的扩散、萌发、防御以及幼苗的生长等都具有重要的生态学意义, 是荒漠植物适应干旱少雨的生态环境的有效对策之一。对粘液种子的研究不仅可全面揭示荒漠植物的生态适应机制及其进化生态意义, 还可为研究基因控制的糖类生物合成和分泌、细胞次生壁的生物合成及形态分化建立理想的模式体系。为此, 在广泛查阅相关文献的基础上, 该文综合分析了国内外种子粘液的研究进展, 并重点探讨了以下几方面问题: (1)种子粘液的化学成分; (2)粘液及粘液种皮的形态特征; (3)粘液细胞分化与粘液生物合成的细胞学及基因调控机制以及粘液的释放方式; (4)种子粘液的生态学意义。在此基础上展望了今后的研究方向, 以期为推动我国荒漠植物种子生态学的理论与应用研究及西部荒漠区的植物物种多样性保护和生态保育提供重要理论依据。

Abstract: Seed mucilage consists of pectin polysaccharides that are secreted by the Golgi apparatus in epidermal cells to the cell cavity and cell walls of the seed coat, which swells considerably upon wetting. Mucilagineous seeds commonly are found in species of Brassicaceae, Asteraceae, Plantaginaceae and several other flowering plant families. Many taxa with mucilageous seeds occur in deserts. Seed mucilage is ecologically advantageous for seed dispersal, germination, seedling development and protection of seed, and thus it is an adaptation of plants to deserts and sand dunes. In addition to furthering our understanding of the ecological and evolutionary aspects of desert plants to their environment, research on mucilaginous seeds will be helpful in building a model system for exploring gene control mechanisms of carbohydrate synthesis and secretion, secondary cell wall biosynthesis and cell morphogenesis. In this paper, we review recent advances on mucilaginous seeds, with emphasis on (1)chemical composition of seed mucilage; (2)morphological characteristics of mucilaginous seed coats and mucilage; (3) biochemical processes in and genetic regulation of differentiation of mucilage-secreting cells, mucilage biosynthesis and mucilage secretion in the seed coat; and (4) ecological significance of seed mucilage. Finally, prospects for further research in this area are discussed. Our purpose is to promote research on the seed biology of desert plants in China and to provide additional justification for protection of biodiversity and for ecological conservation in the desert region of northwest China.