From metabolic markers to mechanism of growth suppression: understanding the molecular physiology of sprouting in potato

Controlling sprouting during storage is critical to the £4bn UK potato industry yet
increasing legislative restictions on chemical suppressants pose serious
challenges, with a potential ban on the most widely used agrichemical. A deeper
understanding of the sprouting process is required to identify novel solutions to
the problem.
Sprouting involves re-activation from quiescence of groups of stem cells in tuber
"eyes" and mobilisation of storage reserves from the surrounding tuber. Via a
metabolomic study on staged, dissected buds we have shown that TCA cycle
metabolites are very early markers of sprouting.
The TCA pathway is a core process generally linked with ATP generation.
However, there is significant evidence that the pathway can also work in a
partial, non-cyclic fashion in specific tissues under certain conditions, playing an
important role in the generation of carbon skeletons and reducing power for
growth. Our data are consistent with the hypothesis that during the earliest
stages of sprouting the TCA "cycle" is working in such a non-canonical fashion.
Understanding the sequence and spatial patterning of TCA-related events
around the bud sprouting