Showing posts with label Nitrogen uptake. Show all posts
Showing posts with label Nitrogen uptake. Show all posts
Saturday, 2 April 2016
Nitrogen uptake, assimilation and remobilization in plants: challenges for sustainable and productive agriculture
Nitrogen uptake, assimilation and
remobilization in plants: challenges for sustainable and productive agriculture
I.
Introduction
Nitrogen is one of
the most expensive nutrients to supply and commercial fertilizers represent the
major cost in plant production. Productive agriculture needs a large amount of
expensive nitrogenous fertilizers. Improving nitrogen use efficiency (NUE) of
crop plants is thus of key importance. NUE definitions differ depending on
whether plants are cultivated to produce biomass or grain yields. However, for
most plant species, NUE mainly depends on how plants extract inorganic nitrogen
from the soil, assimilate nitrate and ammonium, and recycle organic nitrogen.
Furthermore, there
is serious concern regarding nitrogen loss in the field, giving rise to soil
and water pollution. Incomplete capture and poor conversion of nitrogen
fertilizer also causes global warming through emissions of nitrous oxide. NUE
in plants is complex and depends on nitrogen availability in the soil and on
how plants use nitrogen throughout their life span. As a concept, NUE is
expressed as a ratio of output (total plant N, grain N, biomass yield, grain
yield) and input (total N, soil N or N-fertilizer applied). Increasing NUE and
limiting nitrogen fertilizer use are both important and challenges to preserve
the environment and improve a sustainable and productive agriculture.
