Light availability and plant shade tolerance modify plant-microbial interactions and feedbacks in subtropical trees

Area of Science:

• Ecology
• Forest Ecology
• Plant-Soil Interactions

Background:

• Plant-soil feedbacks (PSFs) are crucial for forest species coexistence.
• Limited understanding exists on how light availability and plant-microbial interactions modulate PSFs based on tree shade tolerance.

Purpose of the Study:

• To investigate the influence of light availability and tree shade tolerance on PSFs.
• To explore the role of soil microbial communities in mediating these interactions.

Main Methods:

• A glasshouse experiment was conducted to assess PSFs under varying light conditions.
• Soil bacterial and fungal communities were analyzed using 16S rRNA and ITS2 gene sequencing.

Main Results:

• Under low light, PSFs correlated positively with shade tolerance.
• Under high light, less shade-tolerant species exhibited the most positive PSFs.
• Arbuscular mycorrhizal fungi abundance was the primary driver of PSFs under high light, but not under low light.

Conclusions:

• PSFs and plant shade tolerance interact to promote species coexistence in forests.
• Soil microbes play a significant role in mediating PSFs, with their influence varying by light availability.