To identify feedback signal(s) controlling nitrate uptake by wheat roots, the effects of 13 amino acids on time course of net nitrate influx have been investigated. A new non-invasive technique of measuring net nitrate influx with a high time resolution of minutes has enabled us to make this comparison. The results showed that glutamate caused a rapid and large decrease of net nitrate influx by roots. Aspartic acid, asparagine, glutamine caused a relatively slow decrease of net nitrate influx with a lag of 0.5–1.5 h. Other amino acids had a small effect or even no effect. It is speculated that glutamate is most likely to be a negative feedback signal.
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Communicated by J. Zhang
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Li, J.Z., He, G.Y. & Cram, W.J. The effect of amino acids on nitrate uptake by wheat roots. CEREAL RESEARCH COMMUNICATIONS 38, 482–488 (2010). https://doi.org/10.1556/CRC.38.2010.4.4
- amino acids
- nitrate uptake
- Triticum aestivum L.