F. Fodor et E. Cseh, EFFECT OF DIFFERENT NITROGEN-FORMS AND IRON-CHELATES ON THE DEVELOPMENT OF STINGING NETTLE, Journal of plant nutrition, 16(11), 1993, pp. 2239-2253
The development of stinging nettle (Urtica dioica L.) grown on culture
solution containing with either ammonium or nitrate ions, or urea, wa
s investigated under iron deficiency conditions, and with added FeEDTA
or FeCl3. Both seed-cultured and vegetatively-cultured stinging nettl
e plants produced normally developed green shoots when nitrate and 4 m
u M FeEDTA or FeCl3 were supplied. Stinging nettle plants were able to
utilize Fe-citrate, Fe-ascorbate, and Fe-malate effectively at the sa
me concentration as well. When K3Fe(CN)6 was supplied, which is imperm
eable to the plasmalemma, and therefore is used to measure the reducti
ve capacity of the roots, stinging nettle plants became chlorotic beca
use the complex was stable at the pH of the culture solution. Urea did
not induce chlorosis but inhibited growth. The plants died when ammon
ium was supplied as a sole N source. Applying bicarbonate and ammonium
together prevented the plants from dying, but the plants became chlor
otic. Total exclusion of iron from the culture solution resulted in ir
on-deficiency stress reactions as has been described for other dicotyl
edonous plants (Strategy II).