Agriculture Reference
In-Depth Information
Nitrogen deficiency limits plant size and diminished metabolic activity in the leaves as a result
of which photosynthesis is reduced. It is also among the components of many enzymes that partici-
pates in many metabolic processes in the growth and development of plants. The GHI is improved
with the addition of an adequate amount of N in the crop plants. It has a significant positive associa-
tion with grain yield. It can be concluded that the adequate N status of the plants is a major factor in
determining the yield of field crops.
A greater response to N application by modern crop cultivars is related to ideal plant architec-
ture, including strong and stiff stem and vertical arrangement of leaves, which are responsible for
lodging resistance and higher interception of radiation and use efficiency. In addition, modern crop
cultivars also have resistance to biotic and abiotic stresses, which is also responsible for permitting
the use of higher N application rate and consequently improving yields. Plant breeding and the use
of adequate management practices have contributed significantly to improving crop yields in the
past few decades. There is still a large gap between potential yield and actual yield obtained by the
farmers in developed as well as developing countries. Hence, in the author's opinion, the observed
yield gap indicates that average crop yields can still be significantly improved by management and
breeding. In crop management practices, N fertilization will play a significant role in increasing
crop yields.
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