An evaluation of plant-borne factors promoting the solubilization of alkaline rock phosphates

• DOI: 10.1007/bf02369971
• Publication Date: 2006-04-08T13:14:26Z
• Authors: T. Bekele; B. J. Cino; P. A. I. Ehlert; A. A. Van Der Maas; A. Van Diest
• Keywords: Alkali soil; Phosphorite; Alkaline earth metal; Plant Physiology

Four experiments are described in which the uptake patterns of various crop species were shown to enhance the solubilization of alkaline rock phosphates. In most cases, such enhancements resulted from soil acidification brought about by the alkaline uptake patterns. In one case, the enhancement may have stemmed primarily from a high Ca-uptake rate, which might be responsible for a shift in mass-action equilibria favoring the solubilization of rock phosphates. High uptake of Ca is expected to serve two purposes: 1. it acts in creating alkaline uptake patterns causing a decline in soil pH, and 2. it promotes a shift in mass-action equilibria.