Assimilate Allocation and Redistribution

Jerusalem artichokes temporarily store assimilates in several locations within the plant that are in excess to the amount needed for structural and maintenance purposes. Most of these reserves are reallocated to the tubers during bulking. While a cross section of assimilates is found in these sites, carbohydrates predominate, of which inulin is the primary storage form. In addition to mono- and disaccharides and small amounts of starch, a number of nutrients are found, many of which are phloem mobile and reallocated to the tubers during the latter part of the growing season. 

Biology and Chemistry of Jerusalem Artichoke Helianthus tuberosus L. 

Accumulation of fructans is enhanced by high light intensity and moderate temperatures. It is reduced by excess nitrogen or insufficient potassium (Soja and Haunold, 1991). Distribution of assimilates initially occurs on the periphery of the stem with subsequent movement inward. The portion of the stem receiving assimilates is dictated by its vascular connections. Radial movement inward is restricted to cells interior to vascular bundles. 

The accumulation and redistribution of assimilates can be viewed as changes in dry matter, carbon, individual nutrient elements, or specific compounds (e.g., sucrose) or classes of compounds (e.g., inulins). In the following subsections, the quantitative and temporal accumulation and subsequent redistribution of dry matter, carbon, and nutrient elements in the various locations within the plant are described. 

Therefore, while flowering is not necessary for tuberization, it not only is temporally associated in short-day clones, but also indirectly influences tuber development. 

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