Appraisal of foliar spray of iron and salicylic acid under artificial magnetism on morpho-physiological attributes of pea (Pisum sativum L.) plants.

The appraisal of foliar treatment of iron (Fe) and salicylic acid (SA) on plant under artificial magnetism is very crucial in understanding its impact on growth and development of plants. The present study was designed to document the potential role of Fe and SA on pea (Pisum sativum L.) Matore variety exposed to different magnetism treatments (geomagnetism and artificial magnetism). Thus a pot experiment was conducted using Completely Randomized Design under factorial with three replicates. Various artificial magnetic treatment were applied in pots prior to sowing. Further, 15 days germinated pea seedlings were foliarly supplemented with 250 ppm Fe and 250µM SA, moreover after 20 days of foliar fertilization plants were harvested to analyze and record various morpho-physiological attributes. Data elucidate significant variations in pea plants among different treatments. Artificial magnetism treatments in combination with foliar application of Fe and SA significantly improved various growth attributes (root and shoot length, fresh and dry weights of root and shoot, leaf area), photosynthetic pigments (Chl a, b and carotenoids) and the contents of soluble sugars. However, oxidative stress (H2O2 and MDA) enhanced under different magnetism treatment but foliar application of Fe and SA hampered the production of reactive oxygen species thereby limiting the concentration of H2O2 and MDA in plant tissues. Furthermore the accumulation of nutrients (iron, potassium and nitrate) profoundly increased under artificial magnetism treatment specifically under Fe and SA foliar treatment excluding nitrate where Fe foliar treatment tend to limit nitrate in plant. Consequently, the present research interestingly highlights progressive role of Fe and SA foliar treatment on pea plants under artificial magnetism. Thus, foliar supplementation may be suggested for better growth and development of plants combined with magnetic treatments.

Exogenous Application of Salicylic Acid and Hydrogen Peroxide Ameliorate Cadmium Stress in Milk Thistle by Enhancing Morpho-Physiological Attributes Grown at Two Different Altitudes.

Cadmium (Cd+2) is a potential and widespread toxic environmental pollutant, mainly derived from a rapid industrial process that has inhibitory effects on growth, physiological, and biochemical attributes of various plant species, including medicinal plants such as Silybum marianum L. Gaertn commonly known as milk thistle. Plant signaling molecules, when applied exogenously, help to enhance/activate endogenous biosynthesis of potentially important signaling molecules and antioxidants that boost tolerance against various abiotic stresses, e.g., heavy metal stress. The present study documented the protective role of salicylic acid (SA;0.25 µM) and hydrogen peroxide (H2O2; 10 µM) priming, foliar spray, and combinational treatments in reducing Cd+2 toxicity (500 µM) in milk thistle grown at two diverse ecological zones of Balochistan Province of Pakistan i.e., Quetta (Qta) and Turbat (Tbt). The morpho-physiological and biochemical attributes of milk thistle were significantly affected by Cd+2 toxicity; however, priming and foliar spray of SA and H2O2 significantly improved the growth attributes (root/shoot length, leaf area, and root/shoot fresh and dry weight), photosynthetic pigments (Chl a, b, and carotenoids) and secondary metabolites (Anthocyanin, Soluble phenolics, and Tannins) at both altitudes by suppressing the negative impact of Cd+2. However, the oxidative damage parameters, i.e., MDA and H2O2, decreased astonishingly under the treatment of signaling molecules, thereby protecting membrane integrity under Cd+2 stress. The morphological variations were profound at the low altitude (Tbt) as compared to the high altitude (Qta). Interestingly, the physiological and biochemical attributes at both altitudes improved under SA and H2O2 treatments, thus hampered the toxic effect of Cd+2. These signaling compounds enhanced tolerance of plants under heavy metal stress conditions with the consideration of altitudinal, and ambient temperature variations remain to be the key concerns.