Abstract:
Soil salinity with different
harmful effects on plant growth and
productivity is one of the main reasons in
diminishing biological nitrogen fixation and
nitrogen assimilation in legume plants.
Molybdate has a key role on nitrogen
metabolism of plants and can be has a
beneficial effect on it. Thus, this experiment
was conducted to evaluate the effects of
sodium molybdate spraying (0.2 and 0.4%
solutions in water) on nodulation, nitrogen
uptake and translocation in soybean plants
under different levels of salt stress (0, 5 and
10 dS m-1 NaCl, respectively). Salinity
reduced the nodulation, root and shoot
growth and special flavonoids content in
roots, which are have a key role in
nodulation includes, daidzein, genistein,
coumestrol and glycitein, also diminished
nitrogenase, glutamine synthetase (GS),
glutamate dehydrogenase (GDH), glutamine
oxoglutarate aminotransferase (GOGAT)
and nitrate reductase (NR) activities in
nodes, nitrogen content of nodes, roots and
leaves, nitrogen uptake and translocation by
soybean plants. Under salt stress and nonsaline
condition, sodium molybdate
treatments improved the nodulation by
increasing flavonoids content of roots, also
these treatments enhanced the plant growth
and nitrogenase, GS, GDH, GOGAT and
NR activities of nodes. Furthermore,
nitrogen content of nodes, roots and leaves,
nitrogen uptake and translocation by
soybean plants improved by sodium
molybdate applications. Both of the sodium
molybdate doses, exposed the similar effects
on improving nodulation and nitrogen
metabolism of soybean.
