Global climatic change leads to many detrimental effects on all life forms. Outstanding case, salinity, and drought are considered multidimensional stress that severely affect plant growth and sustainable agriculture. Thymus vulgaris is a medicinal plant that has phytochemical constituents, and it is threatened by several abiotic stresses caused by climate change. Therefore, the present study aims to evaluate the physiological response and thyme tolerance grown on a newlyreclaimed saline sandy soil under drought conditions and treated by biochar-loaded biofertilizers, nano-zeolite, and nano-silicon through two consecutive seasons. The nanoparticles enhanced plant growth and alleviated the adverse effect of drought. Additionally, a synergistic effect was noticed when combining nanoparticles and biofertilizers. The quadruple combined treatment of nano-zeolite, nano-silicon, biochar, and organic matter (T7) significantly increased thyme morphological traits, photosynthetic parameters, oil, and yield compared to control treatment. Additionally, T7 increased the concentration of endogenous nutrients (N, P, K, Na, Ca, Mg, Zn, Fe, Mn), proline, total phenols, and total flavonoids, in addition to indoleacetic acid, gibberellic acid, and antioxidant enzymes in thyme compared to other treatments. T7 showed the lowest concentration of soluble sugars, abscisic acid, and transpiration rate. Interestingly, T7 increased the medicinal benefits of thyme by increasing its vital hydrocarbons, and oxygenated compounds. These findings introduce a dual benefit of nano-fertilizers in combination with biochar and organic matter in ameliorating soil salinity and drought along with increasing thymegrowth, productivity, and therapeutic value.

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Plant production, soil quality, and a sustainable environment depend on climate change. Drought is a multidimensional stressor that seriously affects plant production. The most sensitive plant to climate change is the invasive goldenrod (Solidago canadensis L.), which has potentially high-value materials that can be used to develop a novel approach to controlling its spread. This study aimed to evaluate the impact of different applications (NPK-chemical fertilizers (T1) as control, nano-silicon (T2), nano-NPK (T3), nano-zeolite-loaded nitrogen (T4), and mixed nano-silicon with nano-zeolite-loaded nitrogen (T5)) on plant growth, flowering, chemical composition, yield, essential oil (EO) productivity, and tolerance of water deficit under newreclaimed soil. The results show that T5 application enhanced morphological traits and photosynthetic parameters (photosynthetic rate, CO2 concentration, and water use efficiency while reducing transpiration rate) in goldenrod plants. Moreover, it promoted the plant nutrients uptake compared to the control. The highest total carbohydrate, flavonoid, and phenol contents, as well as a significant amount of the phytohormone indole-3-acetic acid (IAA), were obtained from the T5 application. Conversely, abscisic acid (ABA) and antioxidant enzymes of catalase (CAT) and superoxide dismutase (SOD) appeared with the highest amounts in control plants (T1).Th interaction effect of T5 and drought stress is indicated by increased EO productivity and therapeutic properties.Previous results provide a way to elevate drought stress resistance for the safety production of S. canadensis and improve their qualitative and quantitative trials as economical solutions to achieve an environmental approach to control their spread.

The present experiment was conducted to determine the effect chemical fertilization rates and foliar application of plant growth regulators PGRs (Kinetin or Napthaleneacetic Acid (NAA) and their interactions on growth, flowering, chemical composition of Ervatamia coronaria plants. The plants were fertilized monthly with NPK at the rate of 2, 4 and 6 g pot-1, in addition to the control plants. Plants received the fertilization treatments were sprayed monthly with either Kinetin or NAA at 50, 100 ppm for each one, while the control plants sprayed with tap water. As general, the results indicated that within each level of fertilizer treatments, treating plants with different concentrations of PGRs (Kinetin or NAA) resulted in significant increase in tested vegetative growth (in terms of plant height, number of branches plant-1, leaf area, number of leaves plant-1, stem diameter, root length, fresh and dry weights of leaves, stems and roots), flowering parameters (Viz number of flowers/ plant, fresh and dry weights of flowers), chlorophylls content, total carbohydrates, N, P , K%, total indoles and total phenols, gibberellins, auxins and cytokinins compared to control, with superiority of NAA particularly the highest concentrations (100 ppm) . Under the same level of PGRs raising the fertilization rate caused a gradual and significant increase in all tested parameters compared to control. Based on the results, it can be recommended that for the highest quality growth and flowering parameters of Ervatamia coronaria, the plants could be sprayed with NAA at 100 ppm combined with 6 g pot-1 NPK.