Hydraulic conductance, resistance, and resilience: how leaves of a tropical epiphyte respond to drought.

Premise: Because of its broad range in the neotropical rainforest and within tree canopies, the tank bromeliad Guzmania monostachia was investigated as a model of how varying leaf hydraulic conductance (K ) could help plants resist and recover from episodic drought. The two pathways of K , inside and outside the xylem, were also examined to determine the sites and causes of major hydraulic resistances within the leaf.

Methods: We measured leaf hydraulic conductance for plants in the field and laboratory under wet, dry, and rewetted conditions and applied physiological, anatomical, and gene expression analysis with modeling to investigate changes in K .

A tale of two plasticities: leaf hydraulic conductances and related traits diverge for two tropical epiphytes from contrasting light environments.

We compared the effects of different light environments on leaf hydraulic conductance (Kleaf ) for two congeneric epiphytes, the tank bromeliads Guzmania lingulata (L.) Mez and Guzmania monostachia (L.) Rusby ex Mez.