nitrate is one of the major sources of nitrogen for the growth of plants. it is taken up by plant roots and transported to the leaves where it is reduced to nitrite in the. the main objective of this research was to investigate stimulatory effects of sodium nitrate, potassium nitrate, ammonia and urea on the production/generation of the nitrate reductase mrna in triticum aestivum plants. the pl...

abstract lettuce is one of the best accumulators of heavy metals and nitrate between leafy vegetables. through this research, it was tried to decreased cadmium absorption with humic acid (ha) and studies the effect of ha on the accumulation and metabolism of nitrate. plants were grown in the peat/perlite and irrigated with hoagland solution with addition of cadmium (2 and 4 mg l -1) and ha (100...

Cucurbita pepo L. plants were grown in plastic pots with 2 kg washed sand per pot at three levels of potassium and sodium nitrate supplies to investigate the effects of nitrate supply on nitrate reductase activity and nitrate reductase expression in the leaves of the plants. Results demonstrated that starvation leads to decrease nitrate reductase activity and nitrate reductase expression. Suppl...

The effect of different sources of nitrate salts (ammonium nitrate, sodium nitrate and potassium nitrate) on nitrate reductase (NR) activity and nitrate reductase expression in the leaves of Foeniculum vulgare seedlings grown in pots containing perlite. Two week old seedlings were treated with 30, 60 and 120 mM aqueous solution of ammonium nitrate, sodium nitrate or potassium nitrate. After 21 ...

The effect of tungsten on the development of endogenous and nitrate-induced NADH- and FMNH(2)-linked nitrate reductase activities in primary leaves of 10-day-old soybean (Glycine max [L.] Merr.) seedlings was studied. The seedlings were grown with or without exogenous nitrate. High levels of endogenous nitrate reductase activities developed in leaves of seedlings grown without nitrate. However,...

Synthesis of nitrate reductase protein and increases in nitrate reductase activity occurred in cultures of the yeast Candida nitratophila when they were incubated in medium containing ammonium nitrate. Similar treatment with glutamine plus nitrate resulted in little increase in nitrate reductase activity, in cultures grown previously with reduced nitrogen compounds, and decreases in enzyme acti...

The assimilation of nitrate in plants involves the reduction of nitrate to ammonia in two steps. The first step requires nitrate reductase, a nitrate-inducible enzyme. When seedlings of squash (Cucurbita maxima L.) were treated with nitrate, both nitrate reductase activity and protein were induced in the cotyledons. Poly(A)(+) RNA was prepared from cotyledons of nitrate-treated seedlings and wa...

Nitrate reductase, the first enzyme in nitrate assimilation, is located at the crossroad of two energy-consuming pathways: nitrate assimilation and carbon fixation. Light, which regulates the expression of many higher-plant carbon fixation genes, also regulates nitrate reductase gene expression. Located in the cytosol, nitrate reductase obtains its reductant not from photosynthesis but from car...