Variation in Elemental Content of Lettuce Grown Under Base-Line Conditions in Five Controlled-Environment Facilities

摘要

An interlaboratory comparison was made of the variation in elemental concentration of leaf lettuce (Lactuca sativa) plants grown under base-line conditions for 28 days in 5 controlled-environment facilities. Two studies were conducted by each of 5 investigators using a sphagnum peat-vermiculite mix obtained from a common source. Plant tissue from all studies was collected and analyzed at 1 laboratory for 10 essential elements (P, K, Ca, Mg, Fe, Mn, B, Zn, Cu, Mo) and 10 non-essential elements (Al, Si, Ti, Sr, Ba, Na, Pb, V, Li, and Sn) by arc emission spectrography. The 10 essential elements occurred at concentrations adequate for normal lettuce growth.