Graviperception in maize plants: is amyloplast sedimentation a red herring?
Land plants perceive gravity and respond to it in an organ-specific way; shoots typically direct growth upwards, roots typically downwards. Historically, at least with respect to maize plants, this phenomenon is attributed to three sequential processes, namely graviperception, the transduction of the perceived signal, and the graviresponse, resulting in a typical (re)positioning of the organ or entire plant body relative to the gravivector. For decades, sedimentation of starch-containing plastids within the cells of special tissues has been regarded as the primary and initiating process fundamental for gravitropic growth (starch-statolith hypothesis). Based on Popper's falsification principle, uncompromising experiments were executed. The results indicate that the model of graviperception based on amyloplast sedimentation does not apply to maize seedlings.
['Edelmann|Hans Georg|HG|http://orcid.org/0000-0001-5397-8895']
D018525:Germination D018522:Gravitropism D018466:Gravity Sensing D007091:Image Processing, Computer-Assisted D018517:Plant Roots D018087:Plastids D036226:Seedlings D003313:Zea mays
Graviperception Gravitropic growth Gravitropism Starch-statolith hypothesis Ethylene Gravi-model Plant signal transduction Tensegrity model