Journal article

Publication year: 1992

Pages: 415-421

Journal: Plant Physiology

Volume number: 99

Issue number: 2

ISSN: 0032-0889

Open access status: Green

DOI Link: https://doi.org/10.1104/pp.99.2.415

Publisher: Oxford University Press

Abstract: 
The effect of low pH on net H+ release and root growth of com (Zea mays L.) and broad bean (Vicia faba L.) seedlings was investigated in short-term experiments at constant pH. Broad bean was more sensitive to low pH than com: the critical values (pH values below which net H+ release and root growth ceased) were pH 4.00 (broad bean) and pH 3.50 (com) at 1 millimolar Ca2+. Both proton release and root growth were progressively inhibited as the medium pH declined. Additional Ca2+ in the root medium helped to overcome the limitations of low pH for net H+ release and root growth. Potassium (for corn) and abscisic acid (for broad bean) increased both net H+ release and root growth rate at the critical pH value. It is concluded that poor root growth at low pH is caused by a lack of net H+ release that may decrease cytoplasmic pH values. Inhibited net H+ release at high external H+ activity is not due to a shortage of energy supply to the H+ ATPase. Instead, a displacement of Ca2+ by H+ at the external side of the plasmalemma may enhance reentry of H+ into root cells.

Harvard Citation style: Yan, F., Schubert, S. and Mengel, K. (1992) Effect of Low Root Medium pH on Net Proton Release, Root Respiration, and Root Growth of Corn (Zea mays L.) and Broad Bean (Vicia faba L.), Plant Physiology, 99(2), pp. 415-421. https://doi.org/10.1104/pp.99.2.415

APA Citation style: Yan, F., Schubert, S., & Mengel, K. (1992). Effect of Low Root Medium pH on Net Proton Release, Root Respiration, and Root Growth of Corn (Zea mays L.) and Broad Bean (Vicia faba L.). Plant Physiology. 99(2), 415-421. https://doi.org/10.1104/pp.99.2.415