Do Faster-Growing Holoparasitic Plant Species Exhibit Broader Niches and Wider Global Distributions?

Parasitic organisms, as an important component of ecosystems, have long been a focal point in ecological research, particularly concerning the relationship between their growth characteristics, ecological niche, and distribution patterns. This study selects the holoparasitic plant species Cuscuta campestris Yunck., Cuscuta australis R.Br., and Cuscuta chinensis Lam. from the Cuscuta subgenus Grammica as model species to explore the relationship between the growth rate, ecological niche breadth, and global distribution patterns of parasitic plants. Through greenhouse experiments and data analysis, the main findings of this study indicate a strong positive correlation between the growth rate, ecological niche breadth, number of global occurrence points, and global distribution area for C. campestris, C. australis, and C. chinensis. The significant correlation between growth rate and ecological niche breadth suggests that the intrinsic growth characteristics of parasitic plants may significantly influence their realized ecological niche. Furthermore, the experimental results show that when C. campestris, C. australis, and C. chinensis parasitize non-native hosts from the Americas, they produce greater biomass than when parasitizing native hosts from China. In conclusion, this study provides new support for ecological theories regarding species adaptability, distribution patterns, and environmental influences, and offers directions for future research.