TY - JOUR
T1 - Release of tartrate as a major carboxylate by alfalfa (Medicago sativa L.) under phosphorus deficiency and the effect of soil nitrogen supply
AU - He, Honghua
AU - Wu, Miaomiao
AU - Guo, Lei
AU - Fan, Chenbin
AU - Zhang, Zekun
AU - Su, Rui
AU - Peng, Qi
AU - Pang, Jiayin
AU - Lambers, Hans
PY - 2020/4/1
Y1 - 2020/4/1
N2 - Aims: Plant growth is often limited by low soil phosphorus (P) availability, soil nitrogen (N) availability may affect plants’ responses to P supply. We studied the growth and physiological responses of alfalfa to soil P supply at different N levels. Methods: Alfalfa (Medicago sativa L.) plants were grown in an alkaline soil supplied with different levels of P (0, 5, and 20 mg kg−1) as monopotassium phosphate, and N (50 and 100 mg kg−1) as ammonium nitrate. Results: Plant biomass and P concentrations always showed positive responses to P addition but not to N addition, nodulation was inhibited by lower P supply and higher N supply. Roots released more phosphatase and carboxylates, mainly tartrate, into the rhizosheath at lower soil P supply and higher N supply. Roots always acidified the rhizosheath, but rhizosheath pH did not vary considerably among treatments. Conclusions: This study demonstrates the release of tartrate as a major carboxylate as affected by soil P supply and N supply, and highlights the importance of investigating plant adaptive strategies for P acquisition from soil with different N availability for proper application of P and N fertilizers.
AB - Aims: Plant growth is often limited by low soil phosphorus (P) availability, soil nitrogen (N) availability may affect plants’ responses to P supply. We studied the growth and physiological responses of alfalfa to soil P supply at different N levels. Methods: Alfalfa (Medicago sativa L.) plants were grown in an alkaline soil supplied with different levels of P (0, 5, and 20 mg kg−1) as monopotassium phosphate, and N (50 and 100 mg kg−1) as ammonium nitrate. Results: Plant biomass and P concentrations always showed positive responses to P addition but not to N addition, nodulation was inhibited by lower P supply and higher N supply. Roots released more phosphatase and carboxylates, mainly tartrate, into the rhizosheath at lower soil P supply and higher N supply. Roots always acidified the rhizosheath, but rhizosheath pH did not vary considerably among treatments. Conclusions: This study demonstrates the release of tartrate as a major carboxylate as affected by soil P supply and N supply, and highlights the importance of investigating plant adaptive strategies for P acquisition from soil with different N availability for proper application of P and N fertilizers.
KW - Carboxylates
KW - Phosphatase
KW - Phosphorus-utilization efficiency
KW - Rhizosheath pH
KW - Tartrate
UR - http://www.scopus.com/inward/record.url?scp=85082550187&partnerID=8YFLogxK
U2 - 10.1007/s11104-020-04481-9
DO - 10.1007/s11104-020-04481-9
M3 - Article
AN - SCOPUS:85082550187
VL - 449
SP - 169
EP - 178
JO - Plant and Soil: An International Journal on Plant-Soil Relationships
JF - Plant and Soil: An International Journal on Plant-Soil Relationships
SN - 0032-079X
IS - 1-2
ER -