Biodiv Sci ›› 2005, Vol. 13 ›› Issue (6): 514-519.  DOI: 10.1360/biodiv.050160

Special Issue: 生物入侵

• 论文 • Previous Articles     Next Articles

Influence of seed predation on regeneration of three Caragana species

Xiaoying Zhao1*, Jizhou Ren2   

  1. 1 Department of Biology, Xinjiang Normal Uviversity, Urumqi 830054
    2 College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730020
  • Received:2005-07-25 Revised:2005-09-01 Online:2005-11-20 Published:2005-11-20

Abstract: The leguminous Caragana species are important vegetation components, which are useful for rehabilitation of degraded ecosystems on the Loess Plateau, China. We studied the influence of seed predation by frugivores on the regeneration of two native leguminous species, C. licentiana and C. opulens, and one exotic species, C. intermedia. The results showed that before dispersal, 88.2% of the seeds of C. licentiana, 29.7%±1.7% of C. opulens, and 43.2%±4.8% of C. intermedia were infected by insects. After dispersal, 100% of the seeds of C. licentiana and C. opulens in all microhabitat were completely predated by seed predators in one to four days. Seed predation rate of C. intermedia was relatively low and differed with mi-crohabitats: 100% in shrub lands, 85.0%±10.0 in grasslands, and 31.0%±8.7% in open land. Seed predators greatly reduce seed quantity, seed dispersal and germination rate of C. licentiana and C. opulens. On the other hand, seed predators may effectively disperse the hard-coated seeds of C. licentiana, which may ex-plain why C. licentiana has become a dominant shrub species in Dingxi County, Gansu Province. Seed predators have little influence on the seeds of C. intermedia.