Background and aims

An integrated understanding of the ecophysiological mechanisms of persistence of buried seeds is essential for understanding plant community dynamics and improving our ability to accurately predict seed persistence. However, little is known about how the interaction of precipitation and microorganisms affects persistence of buried seeds and how well seed traits predict seed persistence, especially in a changing environment.

Methods

Here we determined the combined effect of precipitation and microorganisms on the persistence of buried seeds of 11 species from the Loess Plateau in China, and examined the correlation between seed persistence and seed traits, including seed mass, seed dimensions, seed shape, seed toughness, seed water absorption, total phenolic content, crude protein content and seed longevity.

Results

Seed persistence of all species decreased with increasing precipitation. Fungicide treatment improved seed persistence of all tested species, while the effect size of fungicide treatment on persistence increased with increasing of precipitation. Persistence was positively correlated with seed longevity (P₅₀), seed toughness and total phenolic content in all treatments. Seed water absorption was not correlated with seed persistence. However, the relationship between seed persistence and seed shape, seed mass, crude protein content, seed germination was strongly dependent on environmental conditions.

Conclusions

Changes in precipitation not only affected seed persistence but also the relationship between seed persistence and seed traits. Thus, environmental factors should be fully considered in making predictions about seed persistence based on seed traits.