Delayed leaf senescence induces extreme drought tolerance in a flowering plant.
Drought, the most prominent threat to agricultural production worldwide, accelerates leaf senescence, leading to a decrease in canopy size, loss in photosynthesis and reduced yields. On the basis of the assumption that senescence is a type of cell death program that could be inappropriately activated during drought, we hypothesized that it may be possible to enhance drought tolerance by delaying drought-induced leaf senescence. We generated transgenic plants expressing an isopentenyltransferase gene driven by a stress- and maturation-induced promoter. Remarkably, the suppression of drought-induced leaf senescence resulted in outstanding drought tolerance as shown by, among other responses, vigorous growth after a long drought period that killed the control plants. The transgenic plants maintained high water contents and retained photosynthetic activity (albeit at a reduced level) during the drought. Moreover, the transgenic plants displayed minimal yield loss when watered with only 30% of the amount of water used under control conditions. The production of drought-tolerant crops able to grow under restricted water regimes without diminution of yield would minimize drought-related losses and ensure food production in water-limited lands.
Department of Plant Sciences, University of California, Davis, CA 95616, USA.
Rosa M
RM
Rivero
Mikiko
M
Kojima
Amira
A
Gepstein
Hitoshi
H
Sakakibara
Ron
R
Mittler
Shimon
S
Gepstein
Eduardo
E
Blumwald
D016960:Agrobacterium tumefaciens / Q000235:genetics; D019883:Alkyl and Aryl Transferases / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics; D003583:Cytokinins / Q000378:metabolism; D004190:Disasters; D035264:Flowers; D006861:Hydrogen Peroxide / Q000378:metabolism; D010084:Oxidation-Reduction; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000254:growth & development*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics; D011956:Receptors, Cell Surface / Q000235:genetics; D014026:Nicotiana / Q000235:genetics / Q000254:growth & development*; D014867:Water / Q000378:metabolism*
D001426:Bacterial Proteins; D003583:Cytokinins; D011956:Receptors, Cell Surface; D014867:Water; D006861:Hydrogen Peroxide; D019883:Alkyl and Aryl Transferases; C024274:adenylate isopentenyltransferase; D017346:Protein Serine-Threonine Kinases