Coupling zymography with pH mapping reveals a shift in lupine phosphorus acquisition strategy driven by cluster roots

Phosphorus (P) availability affects the spatial and temporal distribution of phosphatase activity and acidification in the rhizosphere: two strongly interactive key strategies of nutrient acquisition by roots. Zymography was coupled with pH planar optode mapping to reveal the effects of P-availability (P deficiency, or with phytate or Ca(H2PO4)2 amendment) on the spatial distribution of phosphatase activity, pH and rhizosphere extent around the taproot of lupine before and after cluster root formation. Before cluster root formation, phosphorus deficiency increased acid phosphatase activities by 20%, decreased pH by 0.8 units and broadened the rhizosphere extent by 0.4 mm across the taproot. Phytate (80 mg kg−1) addition dampened these changes before cluster root formations. In contrast, the rhizosphere extent of phosphatase activity after cluster root formation was 0.2 mm narrower under P-deficiency than with Ca(H2PO4)2 amendment. Due to cluster root formation, the hotspot areas of alkaline phosphatase activity were 40% larger for lupine grown under P-deficiency than amended with Ca(H2PO4)2. Lupine rhizosphere strategies shifted during growth: increasing phosphatase activity, acidifying soil and broadening the rhizosphere around the taproot are dominant mechanisms before cluster root formation. After cluster root development, the main mechanism is increasing the area of phosphatase activity hotspots around cluster roots to enlarge the exploited soil volume. © 2019 Elsevier Ltd

Ma X.1 , Mason-Jones K.1 , Liu Y.2 , Blagodatskaya E. 1, 4 , Kuzyakov Y. 1, 4, 3 , Guber A.5 , Dippold M.A.6 , Razavi B.S.7
Elsevier Ltd
  • 1 Department of Agricultural Soil Science, Department of Soil Science of Temperate Ecosystems, University of Goettingen, Goettingen, Germany
  • 2 Institute of Crop Science, Nutritional Crop Physiology, University of Hohenheim, Stuttgart, Germany
  • 3 Institute of Physicochemical and Biological Problems in Soil Science, Pushchino, Russian Federation
  • 4 Agro-Technology Institute, RUDN University, Moscow, Russian Federation
  • 5 Michigan State University, East Lansing, United States
  • 6 Biogeochemistry of Agroecosystems, University of Goettingen, Goettingen, Germany
  • 7 Institute of Plant and Soil Science, University of Kiel, Kiel, Germany
Ключевые слова
Phosphatase activity; Phosphorus availability; Planar optode; Rhizosphere extent; Rhizosphere pH; Zymography
Дата создания
Дата изменения
Постоянная ссылка

Другие записи