Growth, biomass production and ions accumulation in Atriplex nummularia Lindl grown under abiotic stress

ABSTRACT Atriplex nummularia is a halophyte of great importance in the recovery of saline soils and is considered as a model plant to study biosaline scenarios. This study aimed to evaluate biometric parameters, biomass production and the accumulation of ions in A. nummularia grown under abiotic stresses. Cultivation was carried out in a Fluvic Neosol for 100 days, adopting two water regimes: 37 and 70% of field capacity. Plants were irrigated with saline solutions containing two types of salts (NaCl and a mixture of NaCl, KCl, MgCl2 and CaCl2) at six levels of electrical conductivity: 0, 5, 10, 20, 30 and 40 dS m-1, arranged in a 6 x 2 x 2 factorial with 4 replicates, forming 96 plots. At the end of the experiment, plants were divided into leaves, stem and roots, for the determination of fresh matter (FM), dry matter (DM) and estimated leaf area (LA), besides the contents of Ca2+, Mg2+, Na+, K+ and Cl-. The type of salt did not influence plant growth or biomass production; however, it influenced the levels of Ca2+, Mg2+, Na+ and Cl- in the leaves and Mg2+, K+ and Cl- in the roots. Increase in salinity reduced the contents of Ca2+, Mg2+, Na+, K+ and Cl- for all treatments

Salinity Effects on Germination of Artemisia herba–alba Asso: Important Pastoral Shrub from North African Rangelands

Artemisia herba–alba Asso (known in Arabic as Shih) is an evergreen aromatic shrub endemic in North African rangelands with high pastoral and medicinal relevance. The present work was designed to determine the effect of four soluble salts (NaCl, Na2SO4, MgCl2, and CaCl2) on germination of A. herba–alba seeds. Four concentrations (0, 50, 10, and 150 mM) of each salt were used to test the influence of salinities on germination percentage (GP), rate of germination (RG), and germination tolerance index (GTI %). The experiment was conducted in a controlled incubator with a 12h–photoperiod under 15°C dark/25°C light. The results showed that both GP and (RG) decreased significantly with salinity, and the highest GP was observed in the distilled water control (∼ 80%). The germination tolerance index (GTI %) revealed that A. herba–alba seeds were more tolerant to CaCl2 than other soluble salts. Comparatively, at high salt concentrations, MgCl2 and Na2SO4 were generally the most toxic salts followed by NaCl and CaCl2. The germination of A. herba–alba over a wide range of soluble salts suggests that this species can establish in salt-degraded soils. Therefore, this species appears a promising candidate for the rehabilitation of rangeland with saline soils.The Rangeland Ecology & Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information