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Abstract Background Peace lily (Spathiphyllum wallisii Regel) is an ornamental indoor plant with promising cut flower market, as well as antiviral, pharmacological and ecological potentials. Water deficiency can have sound effects on the growth performance and aesthetic quality of such plant. The aim of this study was to investigate the consequences of zeolite, biochar, and zeo-char loaded nano-nitrogen application on the growth performance and biochemical components of peace lily under water shortage conditions. An experiment was conducted over two consecutive seasons (2021–2022) at the experimental nursery of Ornamental Horticulture Department, Faculty of Agriculture, Cairo University, Giza, Egypt. Soil amendments; zeolite, biochar, and zeo-char loaded nano-nitrogen were prepared and applied to soil before cultivation. Results Our results revealed that the new combination treatment (zeo-char loaded nano-N) had an exceeding significant effect on most of the studied parameters. Vegetative traits such as plant height (35.7 and 35.9%), leaf number per plant (73.3 and 52.6%), leaf area (40.2 and 36.4%), stem diameter (28.7 and 27.1%), root number (100 and 43.5%) and length (105.7 and 101.9%) per plant, and fresh weight of leaves (23.2 and 21.6%) were significantly higher than control (commercially recommended dose of NPK) with the application of zeo-char loaded nano-N during the two growing seasons, respectively. Similar significant increments were obtained for some macro- (N, P, K, Mg, Ca) and micro- (Fe, Zn, Mn) elements with the same treatment relative to control. Chlorophyll (18.4%) and total carotenoids (82.9 and 32.6%), total carbohydrates (53.3 and 37.4%), phenolics (54.4 and 86.9%), flavonoids (31.7% and 41.8%) and tannins (69.2 and 50%), in addition to the phytohormone gibberellic acid (GA3) followed the same trend with the application of zeo-char loaded nano-N, increasing significantly over control. Leaf histological parameters and anatomical structure were enhanced with the new combination treatment in comparison with control. Antioxidant enzymes (catalase and peroxidase), proline and abscisic acid (ABA) exhibited significant declines with zeo-char loaded nano-N treatment relative to control. Conclusion These findings suggest that incorporating soil amendments with nano- nutrients could provide a promising approach towards improving growth performance and quality of ornamental, medicinal and aromatic species under water deficiency conditions.

Root knot nematode (RKN), Meloidogyne incognita, is considered a major soil-borne pathogen that can cause severe yield losses for vegetables and diverse crops. Usually, reducing of M. incognita damage is mainly relies on the application of nematicides and good agricultural practices. However, the use of synthetic nematicides is restricted due to concerns about their impact on the environment and human health. As a result, the use of alternative strategies is becoming necessary to combat RKN resistance. This study evaluates the antagonistic impact of the root mutualistic fungus Pirforomospora indica on M. incognita. It also assesses its influence on the nutritional status, photo-synthesis, antioxidant enzyme activity, endogenous abscisic acid (ABA) levels, and selected ABA related-responsive genes in cucumber plants. Roots of cucumber seedlings were inoculated with P. indica and the second-stage juveniles (1000 J2 per plant). The results demonstrated that P. indica significantly reduced M. incognita invasion in roots, resulting in a 24% reduction in root galling and 42.6% decline in final population. Inoculating plants with both P. indica and RKN increased performance of root fresh and dry weight, as well as improved photochemical efficiency of PSII (Fv/Fm), photosystem II efficiency (PSII), catalase (CAT), peroxidase (POD), and superoxide dis-mutase (SOD). Furthermore, P. indica colonization, either alone or in combination with M. incognita, significantly improved number of fruits per plant, average fruit weight, the plant's marketable yield, and leaf nutrient content (N, P, K and Mg), Moreover, there was an increase in IAA content combined with a decrease in ABA content in roots of dual inoculation plants, if compared to M. incognita infested plants. The highest ABA content was recorded in the root of RKN-cucumber plants. The decline in ABA content due to P. indica treatment was consistent with the modulation of ABA pathway genes, specifically PP2C, PYL1, RK2,1, and RK2,2. The mixed of P. indica and M. incognita led to a decrease in the expression of PP2C, PLY1, RK2,1, and RK2,2 in comparison to the control group. These results indicate that P. indica application could help reduce the negative effects of RKN on important crops.

Water deficiency and chemical fertilizers' pollution are two of many factors causing imbalance in the ecosystem rhythm, which reflects on farm livestock quality and quantity, particularly in arid and semi-arid regions. Limited research is available on the use of different sources of nitrogen fertilizers on pasture crops; hence, an open field research experiment was carried out in newly reclaimed soil to investigate the effect of different sources of nitrogen fertilizers on maximizing protein level and production of Guinea grass (Panicum maximum Jacq.) plant under water deficiency. Present data from two successive seasons revealed that: plants received nitrogen in the form of nano particles recorded significant increases in yield, morphological parameters, leaf anatomy, and chemical composition (macro and micro nutrients, total carbohydrates, plant pigments and crude protein) over control (plants that received the recommended dose of NPK fertilizers) in both growing seasons. In addition, endogenous hormones; gibberellins (GA3) and abscisic acid (ABA) beside enzymes; superoxide dismutase (SOD) and peroxidase (POD) had been affected by different treatments. The lowest amounts of cellulose, hemicellulose and lignin were resulted from nitrogen nano particles treatment, while the rates of leaf photosynthesis, stomatal conductance, intercellular CO2 concentration, and water use efficiency were enhanced also by nitrogen nano particles treatment application. The present findings suggested that increasing crude protein level of Guinea grass plant grown in newly reclaimed soil by addition of the mentioned nanoparticles could be a promising approach to improve crop productivity under water deficiency and reduce environmental pollution.

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A field experiment was conducted in sandy soil to assess the effect of different sources of soil conditioners on barley (Hordeum vulgare L. cv. Giza 137) growth and its yield under drought stress. Plants were exposed to two levels of drought stress until grain maturity: (A) drought at 75% available water (AW) with NPK as control (treatment, T1); (B) mild drought stress at 50% AW with foliar spray of nano-silicon at 75 ppm (treatment, T2), foliar spray of nano-zeolite at 75 ppm (treatment, T3), perlite at 4 tons/h (treatment, T4), natural zeolite at 600 kg/ha (treatment, T5), bentonite at 4 tons/h (treatment, T6), and a combined treatment of T2+T3+T4+T5+T6 at the half amount of each material (T7). All the treatments received the recommended doses of organic matter. Vegetative growth and yield characters as well as anatomical characters were recorded. The physical and chemical soil properties were significantly improved by both foliar and soil conditioners application. The nutrients content of the barley crop were augmented under combined treatment (T7) as compared to other treatments. Under that treatment, barley crop chemical components, i.e. protein, ash, chlorophylls, amino acids, vitamins, and fibre were significantly higher compared to other treatments. In addition, gibberellic acid (GA3) and abscisic acid (ABA) content besides antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD) activities were significantly affected by all treatments. The economical profits were achieved, as reflected by an investment factor value equal to or higher than 3, and this was achieved for all tested nanosilicon, zeolite, and soil conditioners indicated the effectiveness and profitability of studied treatments.

Drought stress in arid regions is a serious factor affecting yield quantity and quality of economic crops. Under drought conditions, the application of nano-elements and nano-agents of water retention improved the water use efficiency, growth performance, and yield quantity of drought-stressed plants. For this objective, two field experiments were performed and organized as randomized complete block designs with six replications. The treatments included kaolin (5 t. ha−1) bentonite (12.5 t. ha−1), perlite (1.25 t.ha−1), N-zeolite (1.3 L.ha−1), N-silicon (2.5 L.ha−1), and N-zinc (2.5 L.ha−1). The current study showed that the application of silicon, zinc, and zeolite nanoparticles only positively influenced the morphological, physiological, and biochemical properties of the drought-stressed coriander plant. Exogenous application of N-silicon, N-zinc, and N-zeolite recorded the higher growth parameters of drought-stressed plants; namely, plant fresh weight, plant dry weight, leaf area, and root length than all the other treatments in both seasons. The improvement ratio, on average for both seasons, reached 17.93, 17.93, and 18.85% for plant fresh weight, 73.46, 73.46, and 75.81% for plant dry weight, 3.65, 3.65, and 3.87% for leaf area, and 17.46, 17.46, and 17.16% for root length of drought-stressed plants treated with N-silicon, N-zinc, and N-zeolite, respectively. For physiological responses, the application of N-zeolite, N-silicon, and N-zinc significantly increased leaf chlorophyll content, photosynthetic rate, water use efficiency, chlorophyll fluorescence, and photosystem II efficiency compared with the control in both seasons, respectively. Similar results were observed in antioxidant compounds, nutrient accumulation, and phytohormones. In contrast, those treatments markedly reduced the value of transpiration rate, nonphotochemical quenching, MDA, ABA, and CAT compared to control plants. Regarding the seed and oil yield, higher seed and oil yields were recorded in drought-stressed plants treated with N-zeolite followed by N-silicon and N-zinc than all the other treatments. Application of N-zeolite, N-silicon and N-zinc could be a promising approach to improve plant growth and productivity as well as to alleviate the adverse impacts of drought stress on coriander plants in arid and semi-arid areas.