Ad. Avila et al., EFFECT OF NITROGEN-SOURCE ON GROWTH AND MORPHOGENESIS OF 3 MICROPROPAGATED POTATO CULTIVARS, Potato research, 37(2), 1994, pp. 161-168
Different nitrogen sources (NO3-, NH4+, glutamic acid and their combin
ations) influenced the growth and morphogenic responses (node number,
shoot length, and stem, leaf and root dry weight) of three micropropag
ated potato cultivars (Spunta, Kennebec, Huinkul). Addition of reduced
nitrogen (NH4+ or glutamic acid) in a nitrate medium increased shoot
length and leaf number. The large increase in growth in plants fed wit
h NO3- NH4+ could be explained by higher organic nitrogen content and
enhanced dry matter partition to the shoot. This suggests that reduced
nitrogen source is required, at least as a supplement to NO3-, to enh
ance N assimilation and growth,