Do source-sink relationships modify shoot to root carbon transport in sectored plants?
Bledsoe, Tara*,1, Orians, Colin1, 1 Tufts University, Medford, MA, United States ABSTRACT- Tomato (Lycopersicon esculentum) plants have been shown to exhibit a high degree of sectoriality, with restricted transport of nutrients from particular roots to orthostichous leaves. It is also well known that carbon assimilate in the phloem moves from source to sink, with sink strength having strong influence on the carbon allocation pathway. In this experiment we investigated how sectoriality influences source-sink phloem transport in tomatoes and whether sink strength could modify the pattern of carbon movement outside sectorial pathways. First, we quantified baseline measurements of 13C transport from a focal leaf to different root sectors. Then, plants were grown using a split-pot design where one lateral root was separated and placed in its own pot with no competition for soil resources, while the roots in the main pot competed for resources. The separated lateral root grew faster than a l
