Abstract
Exudation of carboxylic anions and protons by plant roots plays an important role in mobilizing soil P under P-deficiency conditions. The objective of this work was to quantify short-term (6 h) carboxylate and H+ exudation by tomato roots in response to P concentration (0, 0.1, 0.5 and 1.0 mt M P) in nutrient solution (Cp). The exudation rate of tri- and dicarboxylates decreased exponentially with increasing Cp, from 0.3 to 0.03 μmol plant−1 6h−1. At low Cp the predominant exudates were fumarate, citrate and succinate, while at Cp=0.5 and 1.0 mt M the prevalent anions were succinate and citrate. The solution pH declined sharply as Cp was lowered from 0.1 (pH=4.2) to 0 mt M P (pH=3.7).
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Imas, P., Bar-Yosef, B., Kafkafi, U. et al. Phosphate induced carboxylate and proton release by tomato roots. Plant and Soil 191, 35–39 (1997). https://doi.org/10.1023/A:1004262730434
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DOI: https://doi.org/10.1023/A:1004262730434