The effect of some salts and osmotic shock on phosphate uptake in maize roots
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Chlorides, nitrates, and sulfates of alkali metals, ammonium, calcium, and magnesium inhibit Pi uptake into maize root cortex segments. The concentration 100 mM brought about 50–100% inhibition, whereas 10 mM concentration (with the exception of salts of NH4+, Ca2+, Mg2+) about 15–55%. Also potassium benzenesulfonate (100 mM) dramatically decreases Pi uptake.
Osmotic shock also inhibits Pi uptake. Marked decrease of Pi uptake ability proceeds in concentration range 0.12–0.13 M NaCl. Concomitantly, proteins are released into rehydration medium and their amount is proportional to the degree of Pi uptake inhibition.
The effect of 0.13 M NaCl on Pi uptake and protein release is about the same in roots of intact plants, excised roots, root segments and segments of isolated cortex and stele. Roots of intact plants and excised roots are more responsive to osmotic shock than studied segments.
The degree of salt tolerance of glycophytes is in correlation with NaCl concentration, which brings about 50% inhibition of Pi uptake.
KeywordsSalt Tolerance CaSO4 Maize Root Root Segment Intact Plant
- Attia, A. F., Jeanjean, R.: Influence of osmotic shock and of plasmolysis on phosphate uptake by excised corn roots. — Physiol. vég.21: 39–47, 1983.Google Scholar
- Grunwaldt, G., Ehwald, R., Pietzsch, W., Göring, H.: A special role of the rhizodermis in nutrient uptake by plant roots. — Biochem. Physiol. Pflanzen174: 831–837, 1979.Google Scholar
- Kafkafi, U., Valoras, N., Letey, J.: Chloride interaction with nitrate and phosphate nutrition in tomato (Lycopersicon esculentum L.). — J. Plant Nutr.5: 1369–1385, 1982.Google Scholar
- Laštůvka, Z. Minář, J.: [Water culture techniques of higher plants]. In Czech. — Fol. Fac. Sci. nat. Univ. purk. brunensis8: 1–83, 1967.Google Scholar
- Masuda, Y., Sakurai, N., Tazawa, M., Shimmen, T.: Effect of osmotic shock on auxin-induced cell extension, cell wall changes and acidification inAvena coleoptile segments. — Plant Cell Physiol.19: 857–867, 1978.Google Scholar
- Nieman, R. H., Willis, C.: Correlation between suppression of glucose and phosphate uptake and the release of protein from viable carrot root cells treated with monovalent cations. — Plant Physiol.59: 369–371, 1971.Google Scholar
- Rubinstein, B.: Regulation of H+ excretion. Effects of osmotic shock. — Plant Physiol.69: 939 to 944, 1982a.Google Scholar
- Schkarenkova, L. S., Horbacher, R., Preusser, E., Göring, H.: Osmotischer Shock an Maiswurzelspitzen. Charakterisierung der hypotonischen Shocklösung. — Biochem. Physiol. Pflanzen172: 369–377, 1978.Google Scholar