Nitrate Uptake and Assimilation by Wheat Seedlings during Initial Exposure to Nitrate 1
AUTOR(ES)
Ashley, Doyle A.
RESUMO
Nitrate uptake, reduction, and translocation were examined in intact, 14-day-old, nitrogen-depleted wheat (Triticum vulgare var. Knox) seedlings during a 9-hour exposure to 0.2 mm Ca (NO3)2. The nitrate uptake rate was low during the initial 3-hour period, increased during the 3- to 6-hour period, and then declined. By the 3rd hour, 14% of the absorbed nitrate had been reduced, and this increased to 36% by the 9th hour. Shoots accumulated reduced 15N more rapidly than roots and the ratio of reduced 15N to 15N-nitrate was higher in the shoots. A significant proportion of the total reduction occurred in the root system under these experimental conditions. Accumulation of 15N in ethanol-insoluble forms was evident in both roots and shoots by the 3rd hour and, after 4.5 hours, increased more rapidly in shoots than in roots.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=541775Documentos Relacionados
- Wheat leaves emit nitrous oxide during nitrate assimilation
- Influence of Light and Ambient Carbon Dioxide Concentration on Nitrate Assimilation by Intact Barley Seedlings 1
- In Vivo Nitrate Reduction in Relation to Nitrate Uptake, Nitrate Content, and in Vitro Nitrate Reductase Activity in Intact Barley Seedlings 1
- Nitrogen Assimilation and Protein Synthesis in Wheat Seedlings As Affected by Mineral Nutrition. I. Macronutrients 1
- Nitrogen Assimilation and Protein Synthesis in Wheat Seedlings as Affected by Mineral Nutrition. II. Micronutrients 1
