In this article:
It is theorised that shoot tips could photosynthetically be largely self sufficient and tip removal might have no immediate consequences for remaining leaves.
By contrast, the root system is wholly dependent and its elimination should lead to accumulation of photosynthate.
To test this proposition stem cincturing (i.e. ring barking) was applied singly, or in combination with shoot tip excision to potted grapevines, and then photosynthesis was measured some days later.
The Response of Vine Leaf Photosynthesis to Shoot Tip Excision and Stem Cincturing
1972, Sonderdruck aus der Zeitschrift ‘Vitis’, vol 11, pages 193 – 197
Please note accessing PDF may be slow, thank you.