Phosphorus speciation and high-affinity transporters are influenced by humic substances

Jindo, K; Soares, TS; Pereira Peres, LE; Azevedo, IG; Aguiar, NO; Mazzei, P; Spaccini, R; Piccolo, A; Olivares, FL; Canellas, LP

HERO ID

4131004

Reference Type

Journal Article

Year

2016

HERO ID 4131004
In Press No
Year 2016
Title Phosphorus speciation and high-affinity transporters are influenced by humic substances
Authors Jindo, K; Soares, TS; Pereira Peres, LE; Azevedo, IG; Aguiar, NO; Mazzei, P; Spaccini, R; Piccolo, A; Olivares, FL; Canellas, LP
Journal Journal of Plant Nutrition and Soil Science
Volume 179
Issue 2
Page Numbers 206-214
Abstract Phosphorus (P) is a limiting factor for plant growth, especially in highly weathered tropical soils. Plants have several mechanisms to overcome low P availability in soil, such as humic substances, that reduce phosphate (P-i) adsorption on oxide surfaces and enhance soil P availability. However, the direct influence of humic substances on P-i transporters in root cells or the distribution of P species in leaves remains unclear. Tomato seedlings were grown in a sand-vermiculite mixture with low or high P concentrations (10 or 100 mg kg(-1) KH2PO4, respectively) and humic acids (0 or 48 mg C L-1) isolated from vermicompost. Plant responses were evaluated in the fifth week by measuring root and shoot weights and P concentration, and differential expression in the roots of the high-affinity P-i transporter genes LePT1 and LePT2. In addition, the distribution of P species in the leaves was assessed using P-31-NMR. Humic acids increased the root biomass and changed the distribution of P species in the leaves. Inorganic phosphate was the major compound in plants supplied with a high P concentration, whereas in plants supplied with a low P concentration, P-i was only identified in plants not treated with humic acids. Glycerophosphodiester and phosphorylcholine accumulated in plants treated with humic acid, indicating a modified metabolic pathway for economical P consumption at low P concentrations. High transcript accumulation of LePT2 was observed in roots treated with humic acids at both P concentrations. Our results show that humic substances are strategically involved in plant adaptation to P availability.
Doi 10.1002/jpln.201500228
Wosid WOS:000374035700010
Is Certified Translation No
Dupe Override No
Is Public Yes
Keyword humic acids; phosphate transporter; vermicompost