Root-induced changes

H. Marschner, W. J. Horst, P. Martin, and V. Romheld, Root-induced changes in the rhiz-ospherc Importance for the mineral nutrition of plants. Z PJIanzenernaehr. Rodenk. 749 441 (1986). 

H. Mar.schner, Root-induced changes in the availability of micronutrients in the rhizosphere. Plant Roots The Hidden Half (Y. Waisel, A. Eshel, and U. Kakafi, eds.), Marcel Dekker, New York, 1991, p. 503. 

Figure 3 Root-induced changes in pH in an agarose sheet obtained 2 h after embedding a maize root in the gel. Note that while the root lip is making its local rhizosphere more alkaline, the more basal portion is acidifying the rhizosphere. (From Ref. 102.1...

Plant roots and root-induced chemical changes in the rhizosphere strongly affect the bioavailability of trace elements (Hinsinger, 1999). First, root-induced changes in the ionic equilibria influence the bioavailability of trace elements. The differential rates of plant uptake of water and ions in the soil solution result in a depletion or an accumulation of the ions in the... 

The following root-induced changes in the soil occur as an inevitable consequence of the nature of submerged soils and plant adaptations to them. 

Effects of the root-induced changes on the general microbiology of submerged soils are discussed in Chapter 5 and effects on methane production and consumption are discussed in Chapter 8. 1 here discuss specific effects on plant nutrients. 

Li, H., Yang, X., Kirk, G.J.D., Dobbermann, A., 2002. Root-induced changes of potassium in the rhizosphere of lowland rice (Oriza saliva L.). In 17th World Congress of Soil Science, 14-21 August 2002, Bangkok, Thailand, pp. 1282-1-1282-11. 

Youssef, R.A., Chino, M., 1988b. Root-induced changes in the rhizosphere of plants. I. pH changes in relation to the bulk soil. Soil Sci. Plant Nutr. 35, 461 68. 

The primary objective of this study was to investigate the fractionation of copper, cadmium and lead in the rhizosphere soil in an attempt to obtain a better understanding of their availability and subsequent uptake by plants. In this regard, the present chapter focuses on (1) root-induced changes in various fractions of copper, cadmium and lead in the maize rhizosphere using rhizobox and sequential extraction techniques and (2) influences of pH, root exudates and microbial activity on metal fractionation in the rhizosphere of maize, wheat, pea and soybean, based on the results of specially designed experiments. 

The root-induced pH changes, shown on the right side of Fig. 10, were very different from those caused by addition of root exudates alone (Fig. 10, left). In addition to acidification effect of root exudates, root-induced changes in pH occur as a consequence of root respiration and the excretion or reabsorption of H or HCOj (Nye, 1981 Marschner and Romheld, 1996). As shown in Fig. 10 (right), the pH values in all sterilized and some unsterilized rhizosphere soils increased less than 0.3 units compared with the bulk soil. The two exceptions were unsterilized wheat and pea rhizosphere soils, which were a little more acidic than the bulk soil. 

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