Auxin flow-mediated competition between axillary buds to restore apical dominance.
Apical dominance is one of the fundamental developmental phenomena in plant biology, which determines the overall architecture of aerial plant parts. Here we show apex decapitation activated competition for dominance in adjacent upper and lower axillary buds. A two-nodal-bud pea (Pisum sativum L.) was used as a model system to monitor and assess auxin flow, auxin transport channels, and dormancy and initiation status of axillary buds. Auxin flow was manipulated by lateral stem wounds or chemically by auxin efflux inhibitors 2,3,5-triiodobenzoic acid (TIBA), 1-N-naphtylphtalamic acid (NPA), or protein synthesis inhibitor cycloheximide (CHX) treatments, which served to interfere with axillary bud competition. Redirecting auxin flow to different points influenced which bud formed the outgrowing and dominant shoot. The obtained results proved that competition between upper and lower axillary buds as secondary auxin sources is based on the same auxin canalization principle that operates between the shoot apex and axillary bud.
CEITEC-Central European Institute of Technology, Mendel University in Brno, Zemedelska 1, 613 00 Brno, Czech Republic.|Department of Plant Biology, Mendel University in Brno, Zemedelska 1, 613 00 Brno, Czech Republic.
Jozef
J
Balla
CEITEC-Central European Institute of Technology, Mendel University in Brno, Zemedelska 1, 613 00 Brno, Czech Republic.|Department of Molecular Biology and Radiobiology, Mendel University in Brno, Zemedelska 1, 613 00 Brno, Czech Republic.
Zuzana
Z
Medveďová
Department of Plant Biology, Mendel University in Brno, Zemedelska 1, 613 00 Brno, Czech Republic.
Petr
P
Kalousek
CEITEC-Central European Institute of Technology, Mendel University in Brno, Zemedelska 1, 613 00 Brno, Czech Republic.
Natálie
N
Matiješčuková
Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria.
Jiří
J
Friml
CEITEC-Central European Institute of Technology, Mendel University in Brno, Zemedelska 1, 613 00 Brno, Czech Republic.
Vilém
V
Reinöhl
CEITEC-Central European Institute of Technology, Mendel University in Brno, Zemedelska 1, 613 00 Brno, Czech Republic.
Stanislav
S
Procházka
D001692:Biological Transport; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D007210:Indoleacetic Acids / Q000494:pharmacology*; D018532:Pisum sativum / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D010937:Plant Growth Regulators / Q000494:pharmacology*; D010940:Plant Proteins / Q000235:genetics*; D018520:Plant Shoots / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D018547:Plant Stems / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*
D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D010940:Plant Proteins