Dwarfing Maize

Science's STKE  07 Oct 2003:
Vol. 2003, Issue 203, pp. tw398-TW398
DOI: 10.1126/stke.2003.203.tw398

Dwarf versions of rice and wheat have boosted agricultural outputs, in part by devoting more of the plant's growth to the grain than to the stalk and also by improving the plants' ability to survive wind and rain damage. In maize, mutation of the gene brachytic2 (br2) results in dwarfing, where the lower internodes of the stalk are shortened but no other parts of the plant are affected. Multani et al. (see the Perspective by Salamini) show that in br2 plants a reduction in cell size is accompanied by a two- to threefold increase in cell number to yield a plant stalk with enhanced mechanical strength. The br2 gene encodes a protein that is involved in polar auxin transport. A sorghum ortholog of maize br2, dwarf3, produces a dwarf mutant that is also of considerable agronomic interest.

D. S. Multani, S. P. Briggs, M. A. Chamberlin, J. J. Blakeslee, A. S. Murphy, G. S. Johal, Loss of an MDR transporter in compact stalks of maize br2 and sorghum dw3 mutants. Science 302, 81-84 (2003). [Abstract] [Full Text]

F. Salamini, Hormones and the green revolution. Science 302, 71-72 (2003). [Summary] [Full Text]