H. Jochen Schenk, PhD
Professor, Department of Biological Science
Cal State Fullerton
How can plants transport water under negative pressure? The search for the secret ingredient
Vascular plants are the only organisms known to transport water under negative pressure. It has been quite a mystery how they can do this without constantly creating bubbles in their hydraulic systems, and to this day some scientists argue that negative water transport is physically impossible. Yet, the evidence for negative pressure in vascular plants is overwhelming. Our research with a large team of collaborators has led to the rather surprising hypothesis that plants contain a secret ingredient in the hydraulic system, the xylem that prevents the formation of large bubbles under normal operating conditions. We hypothesize that this secret ingredient consists of surface-active galacto- and phospholipids. This talk will present the evidence for such lipids in plant xylem and discuss how they may prevent large bubbles from forming in xylem.