中文摘要：

为了阐明南方菟丝子寄生对加拿大一枝黄花生长和繁殖的影响及机制,分析了南方菟丝子寄生对加拿大一枝黄花形态、生长与繁殖指标的影响,并分析了其生物量与加拿大一枝黄花次生代谢产物含量的相关性.结果表明：南方菟丝子寄生显著降低加拿大一枝黄花株高、基径、主根长度和根直径,显著降低根、茎、叶和总生物量以及花序数、花序主轴长和花序分枝数;尤其是株高、花序数、茎生物量3个指标,被南方菟丝子寄生的植株仅为无寄生植株的1/2、1/5和1/8.南方菟丝子寄生强度对加拿大一枝黄花的株高、根长、茎生物量、总生物量等指标没有显著影响,但高强度寄生组的基径、根体积、叶生物量、根生物量、花序数、花序主轴长、花序分枝数等指标均显著低于低强度寄生组.南方菟丝子寄生显著增加加拿大一枝黄花根鞣质含量和茎黄酮含量.加拿大一枝黄花的生物量与根鞣质含量及茎黄酮含量存在显著负相关.这表明南方菟丝子寄生加拿大一枝黄花后,除了减少其资源获取外,还可能通过改变资源分配方式等途径进一步抑制其生长.

英文摘要：

In order to find out how parasitic Cuscuta australis influences the growth and reproduction of Solidago canadensis,the effects of the parasitism of C. australis on the morphological,growth and reproductive traits of S. canadensis were examined and the relationships between the biomass and the contents of the secondary metabolites were analyzed. The results showed that the parasitism significantly reduced the plant height,basal diameter,root length,root diameter,root biomass,stem biomass,leaf biomass,total biomass,number of inflorescences branches,axis length of inflorescence,and number of inflorescence. In particular,plant height,number of inflorescence and the stem biomass of parasitized S. canadensis were only 1 / 2,1 / 5 and 1 / 8 of non-parasitized plants,respectively. There was no significant difference of plant height,root length,stem biomass and total biomass between plants parasitized with high and low intensities. But the basal diameter,root volume,leaf biomass,root biomass,the number of inflorescences branches,axis length of inflorescence and number of inflorescence of S. canadensis parasitized with high intensity were significantly lower than those of plants parasitized with low intensity. The parasitism of C. australis significantly increased the tannins content in the root and the flavonoids content in the stem of S. canadensis. The biomass of S. canadensis was significantly negatively correlated with the tannin content in the root and the flavonoids content in the stem. These results indicated that the parasitism of C. australis could inhibit the growth of S. canadensis by changing the resources allocation patterns as well as reducing the resources obtained by S. canadensis.