Sodium chloride was found to improve the water balance of A. halimus plants under conditions of high evaporative demand. This improvement was expressed by higher values of turgor pressure and percentage saturation value in plants grown in salinized culture solutions (Knop solution to which sodium chloride was added to give final osmotic potentials of from -3 to -10 bars) as compared with plants grown in the control (Knop) solutions.However, only in leaves of plants grown in saline culture solutions whose osmotic potential did not exceed -5 bars was a constant water potential gradient maintained between the culture solution and the leaf. Furthermore the hydraulic conductivity of the root system appeared to have been impaired by salinity.The improved water balance of plants which were exposed to salinity could be ascribed to a reduction of transpiration. This was due to some extent to an increase of stomatal resistance but also to a highly significant increase of mesophyll resistance to water loss (rm).Photosynthesis was not affected by rm. The ecological implications of the presence of the rm factor to the measured transpiration/photosynthesis ratio are discussed.

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Six extracts (water, ethanol, ethanol‐water, ethyl acetate, dichloromethane, and n‐hexane) of Astragalus caraganae were studied for their biological activities and bioactive contents. Based on high‐performance liquid chromatography‐mass spectrometry (HPLC‐MS), the ethanol‐water extract yielded the highest total bioactive content (4242.90 µg g−1), followed by the ethanol and water extracts (3721.24 and 3661.37 µg g−1, respectively), while the least total bioactive content was yielded by the hexane extract, followed by the dichloromethane and ethyl acetate extracts (47.44, 274.68, and 688.89 µg g−1, respectively). Rutin, p‐coumaric, chlorogenic, isoquercitrin, and delphindin‐3,5‐diglucoside were among the major components. Unlike the dichloromethane extracts, all the other extracts showed radical scavenging ability in the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging assay (8.73–52.11 mg Trolox equivalent [TE]/g), while all extracts displayed scavenging property in the 2,2‐azino‐bis(3‐ethylbenzthiazoline‐6‐sulfonic acid) (ABTS) radical scavenging assay (16.18–282.74 mg TE/g). The extracts showed antiacetylcholinesterase (1.27–2.73 mg galantamine equivalent [GALAE]/g), antibutyrylcholinesterase (0.20–5.57 mg GALAE/g) and antityrosinase (9.37–63.56 mg kojic acid equivalent [KAE]/g) effects. The molecular mechanism of the H2O2‐induced oxidative stress pathway was aimed to be elucidated by applying ethanol, ethanol/water and water extracts at 200 µg/mL concentration to human dermal cells (HDFs). A. caraganae in HDF cells had neither a cytotoxic nor genotoxic effect but could have a cytostatic effect in increasing concentrations. The findings have allowed a better insight into the pharmacological potential of the plant, with respect to their chemical entities and bioactive contents, as well as extraction solvents and their polarity.

The threat of varying global climates has greatly driven the attention of scientists, as climate change increases the odds of worsening drought in many parts of Pakistan and the world in the decades ahead. Keeping in view the forthcoming climate change, the present study aimed to evaluate the influence of varying levels of induced drought stress on the physiological mechanism of drought resistance in selected maize cultivars. The sandy loam rhizospheric soil with moisture content 0.43–0.5 g g–1, organic matter (OM) 0.43–0.55 g/kg, N 0.022–0.027 g/kg, P 0.028–0.058 g/kg, and K 0.017–0.042 g/kg was used in the present experiment. The findings showed that a significant drop in the leaf water status, chlorophyll content, and carotenoid content was linked to an increase in sugar, proline, and antioxidant enzyme accumulation at p < 0.05 under induced drought stress, along with an increase in protein content as a dominant response for both cultivars. SVI-I & II, RSR, LAI, LAR, TB, CA, CB, CC, peroxidase (POD), and superoxide dismutase (SOD) content under drought stress were studied for variance analysis in terms of interactions between drought and NAA treatment and were found significant at p < 0.05 after 15 days. It has been found that the exogenous application of NAA alleviated the inhibitory effect of only short-term water stress, but yield loss due to long-term osmotic stress will not be faced employing growth regulators. Climate-smart agriculture is the only approach to reduce the detrimental impact of global fluctuations, such as drought stress, on crop adaptability before they have a significant influence on world crop production.

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