植物生态学报 ›› 2009, Vol. 33 ›› Issue (4): 681-688.DOI: 10.3773/j.issn.1005-264x.2009.04.006

• 论文 • 上一篇    下一篇

风毛菊花序、种子大小和数量之间的权衡: 资源条件的影响

汪 洋1; 杜国祯1; 郭淑青2; 赵志刚3*   

  1. (1 兰州大学干旱与草地生态教育部重点实验室,兰州 730000);(2 合作民族师专化学与生命科学系,甘肃合作 747000); (3 武汉大学生命科学学院,武汉 430072)
  • 出版日期:2009-07-30 发布日期:2009-07-30
  • 通讯作者: 赵志刚

TRADE-OFF BETWEEN SIZE AND NUMBER OF CAPITULUM AND SEED IN SAUSSUREA JAPONICA: EFFECTS OF RESOURCE AVAILABILITY

WANG Yang1; DU Guo-Zhen1; GUO Shu-Qing2;ZHAO Zhi-Gang3*   

  1. 1Key Laboratory of Arid and Grassland Agro-ecology of the Ministry of Education, Lanzhou University, Lanzhou 730000, China; 2Department of Chemical and Life Sciences, Hezuo National Normal Academy, Hezuo, Gansu 747000, China; 3College of Life Sciences, Wuhan University, Wuhan 430072, China
  • Online:2009-07-30 Published:2009-07-30
  • Contact: ZHAO Zhi-Gang

摘要: 繁殖器官的大小和数量之间的权衡是植物繁殖对策研究的重要问题之一, 但是支持权衡关系的实验研究非常有限。该文以青藏高原东缘高寒草甸菊科风毛菊属优势植物种风毛菊(Saussurea japonica)为材料, 通过不同光照和营养处理, 研究其花序、种子大小和数量之间的关系。结果表明: 光照和营养处理对花序数目没有显著影响, 但对花的大小, 以及种子大小和数量均有显著影响。大小和数量之间的关系同样会受到处理条件的影响: 在对照和低营养处理下, 花序、种子的大小和数量之间呈显著的正相关关系, 而在低光照处理和低光照低营养处理下, 花序、种子的大小和数量之间的关系变为显著负相关, 即出现大小和数量之间的权衡。结果表明: 环境胁迫(比如有限的土壤养分和光资源的抑制)加剧了花序、种子大小和数量之间的权衡。风毛菊花序和种子的大小和数量之间的权衡关系的环境依赖性, 使其能够对外界环境的变化做出响应, 这种繁殖对策能提高其适合度。

Abstract: Aims We predict that limited resources can enhance the trade-off between size and number of capitula and seeds, showing a strategy of plants. We used Saussurea japonica to investigate the relationship under different levels of light and nutrition. Our objectives are to determine 1) effects of different light and nutrition levels on characters of capitula and seeds, 2) the relationship between size and number of capitula and seeds under different light and nutrition levels and 3) whether the limitation of light and nutrition enhances the trade-off between size and quantity of capitula and seeds.
Methods We planted S. japonica in pots under four treatments: combination of two light levels (high and low) and two nutrition levels (high and low). We counted and weighed (after oven-drying at 80 °C for 72 h) capitula and seeds.
Important findings The treatments of light and nutrition had no significant effects on the number of capitula, while the effects on the mass of capitula were significant. The different treatments had significant effects on both size and number of seeds. Moreover, the relationships between size and number were influenced by different treatments of light and nutrition: under control and low nutrition level, significant positive correlations were observed between size and number for the capitula and seeds; however, significantly negative correlations between size and number were found for the capitula and seeds at the low light treatment and the low light + low nutrition treatments, exhibiting the size-number trade-off. Results suggest that environmental stress (such as low soil nutrition and limited light) enhanced the trade-off between size and number of capitula and seeds, consistent with our prediction. The trade-off can be a response of S. japonica to varied environments, which may improve the adaptability of this plant.