Title : Regulation of nitrate uptake
نویسندگان
چکیده
Objectives: The overall objective is to determine the physiological limitation of nitrate uptake by Fuji apple trees on M9 rootstocks in the spring and early summer. This includes: • Measuring the influence of soil temperature on nitrate uptake by the roots • Determining the impact of tree N status on nitrate uptake, by considering that during the period of N remobilisation from storage, xylem sap concentrations of amino acids and amides are high, causing elevated levels in the phloem sap which in turn inhibit root uptake of nitrate (see diagram 1, p 6). • Establishing a new method for measuring the N storage capacity of apple trees by measuring the flux of amino-N translocated in their xylem sap during the period of N remobilization. • Establishing if white fine roots (younger orders of laterals) are the main site of N uptake, by determining if inhibition of nitrate uptake in spring is correlated with the absence of living white fine roots.
منابع مشابه
Effect of AtNRT2.1 transgene on HATS nitrate uptake in transgenic Nicotiana plumbaginifolia
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