Relative contributions of hydraulic dysfunction and carbohydrate depletion during tree mortality caused by drought.

ABSTRACT: Drought-induced tree mortality has been observed worldwide. Nevertheless, the physiological mechanisms underlying this phenomenon are still being debated. Potted Robinia pseudoacacia and Platycladus orientalis saplings were subjected to drought and their hydraulic failure and carbon starvation responses were studied. They underwent simulated fast drought (FD) and slow drought (SD) until death. The dynamics of their growth, photosynthesis, water relations and carbohydrate concentration were measured. The results showed that during drought, growth and photosynthesis of all saplings were significantly reduced in both species. The predawn water potential in both species was ~ -8 MPa at mortality. The percentage loss of conductivity (PLC) was at a maximum at mortality under both FD and SD. For

SUBMITTER: Dai Y 

PROVIDER: S-EPMC5774510 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature