Dg. Blevins et Km. Lukaszewski, BORON IN PLANT STRUCTURE AND FUNCTION, Annual review of plant physiology and plant molecular biology, 49, 1998, pp. 481-500
New and exciting developments in boron research in the past few years
greatly contributed to better understanding of the role of boron in pl
ants. Purification and identification of the first boron-polyol transp
ort molecules resolved much of the controversy about boron phloem mobi
lity. Isolation and characterization of the boron-polysaccharide compl
ex from cell walls provided the first direct evidence for boron crossl
inking of pectin polymers. Inhibition and recovery of proton release u
pon boron withdrawal and restitution in plant culture medium demonstra
ted boron involvement in membrane processes. Rapid boron-induced chang
es in membrane function could be attributed to boron-complexing membra
ne constituents. Boron may affect metabolic pathways by binding apopla
stic proteins to cis-hydroxyl groups of cell walls and membranes, and
by interfering with manganese-dependent enzymatic reactions. In additi
on, boron has been implicated in counteracting toxic effects of alumin
um on root growth of dicotyledonous plants. Molecular investigations o
f boron nutrition have been initiated by the discovery of a novel muta
nt of Arabidopsis thaliana with an altered requirement for boron.