The physiological response of Artemisia annua L. to salt stress and salicylic acid treatment

Abstract

Salinity has a great influence on plant growth and distribution. A few existing reports on Artemisia annua L. response to salinity are concentrated on plant growth and artemisinin content; the physiological response and salt damage mitigation are yet to be understood. In this study, the physiological response of varying salt stresses (50, 100, 200, 300, or 400 mM NaCl) on A. annua L. and the effect of exogenous salicylic acid (0.05 or 0.1 mM) at 300-mM salt stress were investigated. Plant growth, antioxidant enzyme activity, proline, and mineral element level were determined. In general, increasing salt concentration significantly reduced plant growth. Superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were stimulated by salt treatment to a higher enzyme activity in treated plants than those in untreated plants. Content of proline had a visible range of increment in the salt-treated plants. Distribution of mineral elements was in inconformity: Na + and Ca 2+ were mainly accumulated in the roots; K + and Mg 2+ were concentrated in leaves and stems, respectively. Alleviation of growth arrest was observed with exogenous applications of salicylic acid (SA) under salt stress conditions. The activity of SOD and POD was notably enhanced by SA, but the CAT action was suppressed. While exogenous SA had no discernible effect on proline content, it effectively inhibited excessive Na + absorption and promoted Mg 2+ absorption. Ca 2+ and K + contents showed a slight reduction when supplemented with SA. Overall, the positive effect of SA towards resistance to the salinity of A. annua will provide some practical basis for A. annua cultivation.

Jasmonate‐ and abscisic acid‐activated AaGSW1‐AaTCP15/AaORA transcriptional cascade promotes artemisinin biosynthesis in Artemisia annua

“…Numerous reports have shown that methyl jasmonate (MeJA), ABA and salt stress are crucial mediators in AN biosynthesis by activating downstream regulatory genes (Jing et al, 2009; Li et al, 2014; Maes et al, 2011; Paul and Shakya, 2013; Zhou and Memelink, 2016). Hence, we examined whether AaTCP15 was regulated by these treatments.…”

Mycorrhizal dependency and growth response of Gliricidia sepium (Jacq.) Kunth ex Walp. under saline condition

“…Salinity-driven reduction in plant growth has been reported in several plant species such as Acacia auriculiformis (29), Sesbania aegyptiaca and Sesbania grandiflora (30), Acacia nilotica (31), Lotus glaber (32), Trifolium alexandrinum (33); Linum usitatissimum (34), Trigonella foenumgraecum (28) and Artemisia annua (10); however in all these cases mycorrhiza-inoculated plants performed better than uninoculated plants. The beneficial effect of mycorrhizal colonization on plant growth under saline condition has been documented as an impact of improved uptake of soil nutrients by mycorrhizal plants.…”

“…Further, excessive salts in soil could induce osmotic, ionic, and oxidative stresses that severely affect plant growth. Several researchers have demonstrated that mycorrhizal fungi mitigate negative effects of salinity stress and promote plant growth (9)(10)(11).…”

Ocimum metabolomics in response to abiotic stresses: Cold, flood, drought and salinity

“…Salinity stress was given in 5 concentrations viz . 25mM, 50mM, 75mM, 100mM and 125mM NaCl by irrigating the test plant pots with 100ml of NaCl solution [25] constantly for 10 days and at every alternate day during the complete treatment cycle of 30 days. To prevent the plants from osmotic shock, treatment was started with lower concentrations, gradually increasing the concentration daily, until each group.…”