Engineering high-level aluminum tolerance in barley with the ALMT1 gene.
Acidity is a serious limitation to plant production on many of the world's agricultural soils. Toxic aluminium (Al) cations solubilized by the acidity rapidly inhibit root growth and limit subsequent uptake of water and nutrients. Recent work has shown that the ALMT1 gene of wheat (Triticum aestivum) encodes a malate transporter that is associated with malate efflux and Al tolerance. We generated transgenic barley (Hordeum vulgare) plants expressing ALMT1 and assessed their ability to exude malate and withstand Al stress. ALMT1 expression in barley conferred an Al-activated efflux of malate with properties similar to those of Al-tolerant wheat. The transgenic barley showed a high level of Al tolerance when grown in both hydroponic culture and on acid soils. These findings provide additional evidence that ALMT1 is a major Al-tolerance gene and demonstrate its ability to confer effective tolerance to acid soils through a transgenic approach in an important crop species.
Commonwealth Scientific and Industrial Research Organization Plant Industry, GPO Box 1600, Canberra ACT 2601, Australia. manny.delhaize@csiro.au
Emmanuel
E
Delhaize
Peter R
PR
Ryan
Diane M
DM
Hebb
Yoko
Y
Yamamoto
Takayuki
T
Sasaki
Hideaki
H
Matsumoto
D000535:Aluminum / Q000633:toxicity*; D001483:Base Sequence; D001693:Biological Transport, Active / Q000187:drug effects; D018744:DNA, Plant / Q000235:genetics; D017343:Genes, Plant; D005818:Genetic Engineering; D001467:Hordeum / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism; D008293:Malates / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism
D018744:DNA, Plant; D008293:Malates; D010940:Plant Proteins; D011994:Recombinant Proteins; C030298:malic acid; D000535:Aluminum