Biological Yield and Harvest Index

The harvest index is the ratio between economic yield and biological yield. It is usually determined by the weight of the economic component in relation to the total plant weight, and therefore gives an indication of the relative distribution of assimilates between the tubers and the 

Biology and Chemistry of Jerusalem Artichoke Helianthus tuberosus L. 

In the cultivar Sunchoke, grown in southeastern U.S., the harvest index reached 0.70 by the end of the growing season, with a tuber yield of 14.6 t haA High harvest indexes and tuber yields are dependent on the efficient reallocation of dry matter from aboveground into subterranean plant parts. The Sunchoke study suggested that yield could potentially be improved through earlier tuber induction and development (McLaurin et al., 1999). 

Average dry weight yields of Jerusalem artichoke tubers range from 4 to 6 t-ha 1 to 10 to 15 t ha, and vary between 12 and 26% of fresh weight (Denoroy, 1996). Dwarf cultivars tend to have higher dry weight than fresh weight (i.e., 25 to 26% dwt) (Zubr and Pederson, 1993) due to the lower water content of the tubers, which is known to vary with soil moisture and other factors. 

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