Osmotic adjustment in cowpea plants: Interference of methods for estimating osmotic potential at full turgor

Pablo Rugero Magalhães Dourado; Edivan Rodrigues de Souza; Cíntia Maria Teixeira Lins; Hidelblandi Farias de Melo; Hugo Rafael Bentzen Santos; Danilo Rodrigues Monteiro; Martha Katharinne Silva Souza Paulino; Lucas Yago de Carvalho Leal

doi:10.1016/j.plaphy.2019.10.020

Osmotic adjustment in cowpea plants: Interference of methods for estimating osmotic potential at full turgor

Plant Physiol Biochem. 2019 Dec:145:114-119. doi: 10.1016/j.plaphy.2019.10.020. Epub 2019 Oct 18.

Authors

Pablo Rugero Magalhães Dourado¹, Edivan Rodrigues de Souza², Cíntia Maria Teixeira Lins³, Hidelblandi Farias de Melo⁴, Hugo Rafael Bentzen Santos⁵, Danilo Rodrigues Monteiro⁶, Martha Katharinne Silva Souza Paulino⁷, Lucas Yago de Carvalho Leal⁸

Affiliations

¹ Federal Rural University of Pernambuco - UFRPE, Departamento de Agronomia, Rua Dom Manuel de Medeiros, s/n, CEP: 52171-900, Recife, Pernambuco, Brazil. Electronic address: [email protected].
² Federal Rural University of Pernambuco - UFRPE, Departamento de Agronomia, Rua Dom Manuel de Medeiros, s/n, CEP: 52171-900, Recife, Pernambuco, Brazil. Electronic address: [email protected].
³ Federal Rural University of Pernambuco - UFRPE, Departamento de Agronomia, Rua Dom Manuel de Medeiros, s/n, CEP: 52171-900, Recife, Pernambuco, Brazil. Electronic address: [email protected].
⁴ Federal Rural University of Pernambuco - UFRPE, Departamento de Agronomia, Rua Dom Manuel de Medeiros, s/n, CEP: 52171-900, Recife, Pernambuco, Brazil. Electronic address: [email protected].
⁵ Federal Rural University of Pernambuco - UFRPE, Departamento de Agronomia, Rua Dom Manuel de Medeiros, s/n, CEP: 52171-900, Recife, Pernambuco, Brazil. Electronic address: [email protected].
⁶ Federal Rural University of Pernambuco - UFRPE, Departamento de Agronomia, Rua Dom Manuel de Medeiros, s/n, CEP: 52171-900, Recife, Pernambuco, Brazil. Electronic address: [email protected].
⁷ Federal Rural University of Pernambuco - UFRPE, Departamento de Agronomia, Rua Dom Manuel de Medeiros, s/n, CEP: 52171-900, Recife, Pernambuco, Brazil. Electronic address: [email protected].
⁸ Federal Rural University of Pernambuco - UFRPE, Departamento de Agronomia, Rua Dom Manuel de Medeiros, s/n, CEP: 52171-900, Recife, Pernambuco, Brazil. Electronic address: [email protected].

PMID: 31677542
DOI: 10.1016/j.plaphy.2019.10.020

Abstract

Osmotic adjustment is a persisting controversy in studies on the effect of salt and water stress in cowpea crops. Our hypothesis is that the osmotic potential determination method interferes with the osmotic adjustment calculation. The objective of this study was to consider the osmotic adjustment comparing results obtained by pressure-volume (P-V) curves and osmometry. The experiment was conducted in a randomized block design, with six salt water concentrations 0, 20, 40, 60, 80, and 100 mmol L^-1 of NaCl in a Fluvisol. The osmotic adjustment found through osmometry were lower than those found through P-V curves. The apoplastic water fraction of the cowpea had a dilution effect, denoting overestimation of the osmotic potential by the methodology based on osmometry. This may be the source of the different interpretations of osmotic adjustment in cowpea plants. Thus, osmotic adjustment should be calculated preferably using the osmotic potential determined by method of pressure-volume curves.

Keywords: Osmolality; Osmotic adjustment in cowpea; Pressure-volume curve; Sap osmotic potential.

MeSH terms

Osmosis
Osmotic Pressure*
Sodium Chloride / pharmacology
Stress, Physiological / drug effects
Vigna* / physiology
Water / pharmacology

Substances

Water
Sodium Chloride