The effects of auxin and strigolactones on tuber initiation and stolon architecture in potato.
Various transcriptional networks and plant hormones have been implicated in controlling different aspects of potato tuber formation. Due to its broad impact on many plant developmental processes, a role for auxin in tuber initiation has been suggested but never fully resolved. Here, auxin concentrations were measured throughout the plant prior to and during the process of tuber formation. Auxin levels increase dramatically in the stolon prior to tuberization and remain relatively high during subsequent tuber growth, suggesting a promoting role for auxin in tuber formation. Furthermore, in vitro tuberization experiments showed higher levels of tuber formation from axillary buds of explants where the auxin source (stolon tip) had been removed. This phenotype could be rescued by application of auxin on the ablated stolon tips. In addition, a synthetic strigolactone analogue applied on the basal part of the stolon resulted in fewer tubers. The experiments indicate that a system for the production and directional transport of auxin exists in stolons and acts synergistically with strigolactones to control the outgrowth of the axillary stolon buds, similar to the control of above-ground shoot branching.
Laboratory of Plant Breeding, Wageningen University and Research Centre, PO Box 386,  6700 AJ Wageningen, The Netherlands.
Efstathios
E
Roumeliotis
Bjorn
B
Kloosterman
Marian
M
Oortwijn
Wouter
W
Kohlen
Harro J
HJ
Bouwmeester
Richard G F
RG
Visser
Christian W B
CW
Bachem
D001692:Biological Transport; D004357:Drug Synergism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D007210:Indoleacetic Acids / Q000032:analysis / Q000037:antagonists & inhibitors / Q000378:metabolism*; D007783:Lactones / Q000032:analysis / Q000378:metabolism*; D010641:Phenotype; D010937:Plant Growth Regulators / Q000032:analysis / Q000037:antagonists & inhibitors / Q000378:metabolism*; D018515:Plant Leaves / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D018547:Plant Stems / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D035281:Plant Tubers / Q000187:drug effects / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D030821:Plants, Genetically Modified; D011198:Solanum tuberosum / Q000187:drug effects / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D014283:Triiodobenzoic Acids / Q000494:pharmacology
C507382:GR24 compound; D007210:Indoleacetic Acids; D007783:Lactones; D010937:Plant Growth Regulators; D010940:Plant Proteins; D014283:Triiodobenzoic Acids; C052968:2,3,5-triiodobenzoic acid