This paper establishes deficient and toxic levels of nitrogen (N) in t
obacco seedlings of the Virginia type, suggesting that range of concen
tration in the plant required in order to avoid possible nutritional p
roblems before transplanting. The results show that the lamina tends t
o contain more N than does the central midrib. The normal N content ra
nge without visual N deficiency or toxicity symptoms in leaves at the
young seedling stage should be 3.5-6.9% on a dry matter basis.