Growth and uptake of mineral elements in response to sodium chloride of three provenances of maritime pine¹

Abstract

Effect of sodium chloride (NaCl) on the growth, mineral concentration, and net accumulation of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sodium (Na) was established in one-year-old seedlings (Iberique, Landais, Tamjoute provenances) grown in a regulated greenhouse in nutrient solutions. Increasing concentration of NaCl induces a reduced rate of growth and the Iberique provenance was most affected. Accumulation of Na is significantly more intense in the Tamjoute provenance irrespective of the growth response. Macronutrient concentration are markedly modified, as a result of salinity, by increases in the N and K concentrations and decreases in P, Ca and Mg concentrations in the root. The nutrient concentrations in the tissues did not appear to become deficient or toxic under these saline conditions. Total accumulation of most ions was reduced as a consequence of relative growth and provide a good indication of geographic provenance response. The results presented here highlight the importance of Na/K ratio of maritime pine under saline conditions with respect to growth response. The Na/K criterion appears to be a relevant tool for the salinity tolerance estimation of maritime pine.

Growth and elemental composition of jack pine (Pinus banksiana) seedlings treated with sodium chloride and sodium sulfate

“…While high levels of Cl are often found to inhibit NO 3 uptake (Grattan and Grieve 1994), the N concentration of maritime pine (Pinus pinaster Ait.) needles increased in plants treated with NaCl (Saur et al 1995), similar to the results of this study. In jack pine, injury did not appear to be due to nutrient deficiency, as tissue levels of mineral nutrients were higher in NaCl treated seedlings than in control seedlings.…”

Effects of pH on NaCl tolerance of American elm (Ulmus americana) seedlings inoculated with Hebeloma crustuliniforme and Laccaria bicolor

“…For the lower pH treatments, all inoculation groups that were treated with 60 mM NaCl maintained higher chlorophyll concentrations compared with non-inoculated plants. Salt stress frequently triggers leaf chlorophyll reductions that are usually not correlated with the nutrient status of plants (Grattan and Grieve 1994;Saur et al 1995). In our study, the differences in leaf chlorophyll concentrations between inoculated and noninoculated NaCl-treated plants were not correlated with the leaf Na concentrations.…”

Crescimento e acúmulo de cátions em plantas de moringa mantidas em solos salinos

“…Vários outros estudos têm demonstrado redução no crescimento e na produção de biomassa das plantas causados pela salinidade do meio (Lacerda et al, 2001;Miranda et al, , 2005Neves et al, 2004), os quais podem ser devido aos efeitos osmóticos, tornando a água cada vez menos disponível para as plantas, além dos efeitos nutricionais e tóxicos (Munns, 2002). Além disso, há interferência no metabolismo dos açúcares, reduzindo o crescimento e a produção das plantas (Serrato Valenti et al, 1991). Não apenas a área foliar diminui em função da salinidade, mas também a fixação líquida do CO 2 por unidade de área foliar, enquanto que a respiração aumenta, promovendo redução drástica na assimilação líquida de CO 2 por unidade de área foliar por dia.…”

“…Várias pesquisas têm mostrado o aumento da relação Na/K, Na/Ca e Na/Mg em função da salinidade (Azevedo Neto & Tabosa, 2000;Fernandes et al, 2002;Garcia et al, 2007). A manutenção de baixas relações Na/K, Na/Ca e Na/Mg é um importante critério para caracterizar a tolerância das plantas à salinidade (Saur et al, 1995). Quando a relação Na/Ca é alta, o Na promove o deslocamento do Ca da membrana celular, acarretando em perda da sua integridade e consequente desequilíbrio na absorção dos íons (Marschner, 2000).…”