Abstract: Under natural conditions, pathogenic fungal infection is an important factor leading to seed mortality. However, the relationship between seed characteristics (e.g., dormancy and germination rate) and pathogenic fungal infection under climate change is poorly understood. In this study, seeds of 17 herbaceous plant species collected from an alpine meadow of the Qinghai-Tibet Plateau were used to perform a germination trail at different temperatures (10, 15, 20, and 25 ℃). We examined the effect of temperature on seed germination characteristics and fungal infection, and explored the relationship between fungal infection and seed death and seed germination rate and dormancy characteristics under different temperature conditions. There was a significant negative correlation between seed fungal infection rate and seed mortality and seed dormancy under each temperature (P<0.001), with the strongest correlation at 25 ℃. Only at 25 ℃, the fungal infection rate and mortality of seeds were significantly positively correlated with the average germination time of seeds (P<0.05). These results showed that seed dormancy can effectively resist the infection of pathogenic fungi under different temperature conditions. In addition, seeds can effectively escape the infection of pathogenic fungi through rapid germination, but their relationship with pathogenic fungi is greatly affected by temperature. This study provides a scientific basis for understanding the relationship between seed characteristics and pathogenic fungi in the context of climate change.

Key words: temperature, seed survival, seed germination, pathogenic fungus, germination time