光和温度对西双版纳地区先锋树种对叶榕种子萌发的影响  

EFFECTS OF LIGHT AND TEMPERATURE ON SEED GERMINATION OF FI-CUS HISPIDA IN XISHUANGBANNA,SOUTHWEST CHINA

作　　者：陈辉[1] 张霜[1] 曹敏[1] 

机构地区：[1]中国科学院西双版纳热带植物园

出　　处：《植物生态学报》2008年第5期1084-1090,共7页Chinese Journal of Plant Ecology

基　　金：中国科学院重要方向项目(KSCX2-YW-N-066)

摘　　要：该研究应用人工气候箱设置不同的光照和温度梯度,探讨对对叶榕(Ficus hispida)种子萌发的影响。结果表明,荧光灯条件下(红光和远红光比例(R/FR)为4.56,光量子密度(PPFD)约为90μmol·m–2·s–1),温度对种子萌发速率有显著影响,而对最终萌发率的影响不显著。对叶榕的种子为光敏性种子,萌发严格需光,R/FR对种子最终萌发率的影响显著,较高的R/FR促进种子萌发,而较低的R/FR抑制种子萌发。光强影响种子的萌发速率,较弱的光照可以延缓种子萌发,但并不能完全抑制其萌发。在30℃条件下,对叶榕的种子可以在较高的R/FR(0.42)水平下萌发,但温度为23/20℃时,种子对R/FR的要求增高,0.42的R/FR不能导致种子萌发。说明较低的温度和R/FR都可以显著抑制对叶榕的种子萌发,而较高的温度和R/FR皆有利于种子的萌发。Aims Ficus hispida is a common pioneer tree species in the tropical secondary forests of Xishuangbanna, China. Our objective was to determine effects of light and temperature on seed germination ofF. hispida to understand its response to forest microenvironments. Methods Our experiments were carried out in incubator with 14 h light/10 h dark treatments. Experiments to test the effects of temperature on germination were conducted at 35/25, 35/20, 30/20, 25/15 and 30 ℃ under fluorescent light. Neutral-density black plastic film was used to determine the effect of light intensity on germination at 30 ℃. Tests of the effects of R/FR ratio on germination were set at 23/20 and 30 ℃, and R/FR ratio gradients were created by filtering incandescent light through 2, 4 and 6 layers of green plastic film. Important findings The seeds of F. hispida were photoblastic, germinating only in light. RfFR ratio significantly influenced seed germination, followed by temperature and light intensity. Germination could be induced by very low PPFD though delayed. Although the final germinations in all temperature treatments under fluorescent light were 〉96%, mean time to germinate differed among temperature treatments. Seed germination at 0.42 R/FR ratio was inhibited at 23/20 ℃, while much higher and earlier germination was recorded at 30 ℃. In addition, an R/FR ratio of 0.34 significantly inhibited germination at 30 ℃.

关 键 词：先锋种 对叶榕 光敏性 红光与远红光比例 温度 

分 类 号：Q945[生物学—植物学]