How do leaf carbon and nitrogen contents of oak hosts affect the heterotrophic level of Loranthus europaeus? Insights from stable isotope ecophysiology assays

Loranthus europaeus is one of the major plant parasites threatening fragile ecosystems oak forests in western Iran. The mistletoe a hemi-parasite which grows on forest species, especially oaks. Carbon isotope composition (?13C) has been central to understand behaviour mistletoes field. This study investigated C and N compositions leaves L. its host oaks (Quercus libani, Q. infectoria brantii) goal was assess degree heterotrophy, estimate carbon partition between possible consequences this phenomenon for ecology these hemi-parasites. Leaf samples from were collected Mirabad Sardasht, Ten adult trees each with hemiparasite sampled determination leaf dry weight area, concentration nitrogen, contents stable nitrogen isotopes. In all three we found that levels ?13C host, higher than those mistletoes. Quercus infectoria, highest mass per area basis, species negatively related host-mistletoe difference. Our results also showed masses can be indicators heterotrophic an easy alternative ?13C. conclusion, it seems difference reduced when Cmass Nmass increase. condition relates increased mistletoe.