Phosphorus nutrition of Populus × canescens reflects adaptation to high P-availability in the soil

Abstract

Phosphorus (P) constitutes one of five macronutrients essential for plant growth and development due to the central function of phosphate in energy metabolism, inheritance and metabolic control. In many ecosystems, plant available soil-P gets limited by soil aging. Hence, plants have developed adaptation strategies to cope with such limitation by an efficient plant and ecosystem internal P-cycling during annual growth. The natural floodplain habitat of fast-growing Populus × canescens is characterized by high soil-P availability. It was thus expected that the P-nutrition of P. × canescens had adapted to this conditions. Therefore, different P-fractions in different twig tissues were investigated during two annual growth cycles. The P-nutrition of P. × canescens markedly differs from that of European beech grown at low soil-P availability (Netzer F, Schmid C, Herschbach C, Rennenberg H (2017) Phosphorus-nutrition of European beech (Fagus sylvatica L.) during annual growth depends on tree age and P-availability in the soil. Environ Exp Bot 137:194-207). This was mainly due to a lack of tree internal P-cycling during annual growth indicated by the absence of P-storage and remobilization in twig bark and wood. Hence, strategies to economize P-nutrition and to prevent P-losses had not developed. This fits with the fast-growth strategy of P. × canescens at unrestricted P-availability. Hence, the P-nutrition strategy of P. × canescens can be seen as an evolutionary adaptation to its natural growth habitat.

Measurements of 18O‐Pi uptake indicate fast metabolism of phosphate in tree roots

“…; Zavišić & Polle ) and excised poplar roots (Netzer et al . ), were not observed. This could be due to (i) the transport of 18 O‐P i into the xylem and further into aboveground plant parts (Pfahler et al .…”

“…The P demand of plants is met by phosphate (P i ) uptake from the soil solution via roots, and depends on the season in deciduous trees (Netzer et al . ; Spohn et al . ; Zavišić & Polle ).…”

Metabolome and Lipidome Profiles of Populus × canescens Twig Tissues During Annual Growth Show Phospholipid-Linked Storage and Mobilization of C, N, and S

“…Nutrients resorbed from senescing leaves are stored as carbohydrates and storage lipids ( Sauter and Kloth, 1987 ; Sauter et al, 1988 ; Sauter and van Cleve, 1989 , 1994 ; Sauter and Wellenkamp, 1998 ), proteins and amino acids for nitrogen ( Coleman et al, 1991 ; Gessler et al, 1998b ; Cooke and Weih, 2005 ; Millard and Grelet, 2010 ; Wildhagen et al, 2010 ), sulfate and glutathione (GSH) for sulfur ( Herschbach and Rennenberg, 1996 ; Dürr et al, 2010 ; Herschbach et al, 2012 ; Malcheska et al, 2013 ), and phosphate (P i ) as well as organic-bound P i (P org ) for phosphorus ( Netzer et al, 2017 , 2018a ). Broad leaf deciduous tree species store their nutrients in living cells of the twig, i.e., bark parenchyma as well as wood ray and pith cells ( Sauter and Kloth, 1987 ; Sauter and van Cleve, 1994 ; Sauter et al, 1996 ; Sauter and Wellenkamp, 1998 ; Netzer et al, 2018b ). Beside nutrient storage in the bark and wood of the twig, nutrients also accumulate in leaf buds established at the end of the vegetation period ( Herschbach and Rennenberg, 1996 ; Netzer et al, 2017 ) and in seeds during their development ( Hills, 2004 ; Borek et al, 2015 ).…”

“…Broad leaf deciduous tree species store their nutrients in living cells of the twig, i.e., bark parenchyma as well as wood ray and pith cells ( Sauter and Kloth, 1987 ; Sauter and van Cleve, 1994 ; Sauter et al, 1996 ; Sauter and Wellenkamp, 1998 ; Netzer et al, 2018b ). Beside nutrient storage in the bark and wood of the twig, nutrients also accumulate in leaf buds established at the end of the vegetation period ( Herschbach and Rennenberg, 1996 ; Netzer et al, 2017 ) and in seeds during their development ( Hills, 2004 ; Borek et al, 2015 ). Nutrient resorption from senescing leaves and nutrient storage in twig tissues does not only prevent nutrient loss from the tree by leaf abscission ( Rennenberg and Schmidt, 2010 ) and, hence, improves its nutrient use efficiency ( Yuan and Chen, 2015 ; Netzer et al, 2017 ), but also allows conservation of nutrients for the whole ecosystem ( Brant and Chen, 2015 ).…”

“… The temperate climax tree species Fagus sylvatica and the floodplain tree species Populus × canescens possess contrasting phosphorus (P) nutrition strategies. While F. sylvatica has been documented to display P storage and mobilization ( Netzer et al, 2017 ), this was not observed for Populus × canescens ( Netzer et al, 2018b ). Nevertheless, changes in the abundance of organic bound P in gray poplar trees indicated adaptation of the P nutrition to different needs during annual growth.…”