云南西双版纳常见寄生植物生态化学计量特征及其与寄主的关系

Ecological Stoichiometry of Common Parasitic Plants and the Relationship with Their Hosts in Xishuangbanna,Yunnan

对云南西双版纳地区常见的半寄生植物澜沧江寄生(Scurrulachingii var.yunnanensis)、五蕊寄生(Dendrophthoe pentandra)和全寄生植物优势种金灯藤(Cuscuta japonica)的生态化学计量特征及其与寄主关系进行研究。结果表明,相较于普通高等陆生植物,两种半寄生植物叶片的C、N含量及N:P较低,P含量较高,全寄生植物金灯藤的N、P含量较高,N:P较低;两种半寄生植物C:N、C:P均显著高于全寄生植物金灯藤。两类寄生植物C、N、P生态化学计量特征季节差异不显著。相较于全寄生植物,半寄生植物与寄主间具有更强的相关性。全寄生植物金灯藤的化学计量内稳性指数显著高于两种半寄生植物,全寄生植物内稳性雨季显著高于旱季。

In order to explore the ecological stoichiometric characteristics and homeostasis of common parasitic plants in tropical Yunnan,two dominant hemiparasitic species Scurrula chingii var.yunnanensis,Dendrophthoe pentandra and one dominant holoparasitic plant Cuscuta japonica and their hosts were selected in tropical area of Xishuangbanna,Yunnan.The results showed that the leaves of two hemiparasitic plants had lower C,N contents and N:P ration but higher P content compared with common terrestrial plants;holoparasitic plant C.japonica had higher N and P contents,but lower N:P.The C:N,C:P ratios of the two hemiparasitic plants were significantly higher than those of holoparasitic plant C.japonica.There was not significant seasonal variation in stoichiometry of C,N and P of the hemiparasitic and holoparasitic plants.Compared with the holoparasitic plants,the hemiparasitic plants had a stronger correlation with their hosts.The homeostasis indexes of C,N,P stoichiometry of holoparasitic plant C.japonica were significantly higher than those of two hemiparasitic plants.The homeostasis indexes of the holoparasitic plant C.japonica in the rainy season were significantly higher than those in the dry season.