When Do Tubers Start to Form?<BR>Tuber initiation: 6 to 8 Weeks After Foliar Emergence (same time as flowering).
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<BR>Underground structures have more biomass than the aboveground foliage by 6 WAFE.
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<BR>Tuber chains formed by 10 WAFE.
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<BR>Long days stimulate: shoot, root, and rhizomes 
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<BR>Short days stimulate: tuber and floral production.<BR>Hauser 1962<BR>Williams  1982<BR>