Carbon supply-consumption balance in plant roots: effects of carbon use efficiency and root anatomical plasticity.

The growth and maintenance of the plant root system may consume more than 50% of all photosynthates, making the root system a major carbon sink (Lambers et al., 2002). Carbon is supplied to roots via sieve tubes that are located in the phloem of the root stele, and is consumed for anabolic and catabolic processes. In a recent paper, Kong et al., (2021) proposed a framework to assess the carbon supply-consumption balance in plant roots that bridges root anatomical structures and root functioning using 'structural allometric relationships'. Their framework highlights the pivotal role of root radius and associated anatomical properties such as sieve tube radius and the size and number of root cells for the carbon supply-consumption balance.