Search results for " source-sink relations"
showing 2 items of 2 documents
A simple, rapid extraction and assay procedure for the NAD+-dependent sorbitol dehydrogenase (SDH) in peach
1998
Sorbitol is the major photosynthetic product in peach. In sink tissues, sorbitol is converted to fructose via the NAD+-dependent sorbitol dehydrogenase (SDH). A new procedure is described that allows rapid, simple quantification of SDH activity in growing tissues. The procedure uses only 0.01 to 2.5 grams of fresh tissue per sample, such that a single shoot tip, a single root tip, or about 5 g of fruit flesh can be assayed for SDH activity. Storage of samples at 4 or -20 C° over night resulted in significant loss of enzyme activity. Thus, freshly harvested tissues were ground with sand in buffer at 2°C in a mortar and pestle, and the homogenate centrifuged @ 3000 ´ g to remove particulate m…
Transport and partitioning of 13C-photoassimilate between peach fruiting shoots
2008
We used a non-intrusive method (13CO2 feeding) and a manipulative approach to see whether fruiting shoots in peach trees are autonomous or may import carbon from neighboring shoots under forced conditions, and whether the degree of autonomy is influenced by the source-sink relationship on the shoot. In three experiments, leaf to fruit ratio (L:F) of selected fruiting shoots was moderately (2005 and 2006) or strongly (extreme enforcing 2006) altered to either encourage or discourage movement of carbon from 13C-labeled sending shoots (SFS) to receiving fruiting shoots (RFS), both located on the same main scaffold of V-shaped peach trees. At stage I and III of fruit growth, fruit and shoot tip…