Mineral content and biochemical variables of Aloe vera L. under salt stress

PLoS One. 2014 Apr 15;9(4):e94870. doi: 10.1371/journal.pone.0094870. eCollection 2014.

Abstract

Despite the proven economic importance of Aloe vera, studies of saline stress and its effects on the biochemistry and mineral content in tissues of this plant are scarce. The objective of this study was to grow Aloe under NaCl stress of 0, 30, 60, 90 and 120 mM and compare: (1) proline, total protein, and enzyme phosphoenolpyruvate carboxylase (PEP-case) in chlorenchyma and parenchyma tissues, and (2) ion content (Na, K, Ca, Mg, Cl, Fe, P. N, Zn, B, Mn, and Cu) in roots, stems, leaves and sprouts. Proline and PEP-case increased as salinity increased in both parenchyma and chlorenchyma, while total protein increased in parenchyma and decreased in chlorenchyma, although at similar salt concentrations total protein was always higher in chlorenchyma. As salinity increased Na and Cl ions increased in roots, stems, leaves, while K decreased only significantly in sprouts. Salinity increases typically caused mineral content in tissue to decrease, or not change significantly. In roots, as salinity increased Mg decreased, while all other minerals failed to show a specific trend. In stems, the mineral concentrations that changed were Fe and P which increased with salinity while Cu decreased. In leaves, Mg, Mn, N, and B decreased with salinity, while Cu increased. In sprouts, the minerals that decreased with increasing salinity were Mg, Mn, and Cu. Zinc did not exhibit a trend in any of the tissues. The increase in protein, proline and PEP-case activity, as well as the absorption and accumulation of cations under moderate NaCl stress caused osmotic adjustment which kept the plant healthy. These results suggest that Aloe may be a viable crop for soil irrigated with hard water or affected by salinity at least at concentrations used in the present study.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aloe / drug effects*
  • Aloe / growth & development
  • Aloe / metabolism*
  • Aloe / physiology
  • Dose-Response Relationship, Drug
  • Hydrogen-Ion Concentration
  • Minerals / metabolism*
  • Phosphoenolpyruvate Carboxylase / metabolism
  • Plant Proteins / metabolism
  • Proline / metabolism
  • Sodium Chloride / pharmacology*
  • Stress, Physiological / drug effects*

Substances

  • Minerals
  • Plant Proteins
  • Sodium Chloride
  • Proline
  • Phosphoenolpyruvate Carboxylase

Grants and funding

This research was support by grant ZA3.1 from CIBNOR, project Fundación Produce Baja California Sur, A.C., project CIBNOR-UABCS and project SEP-CONACYT 180C. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.