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Abstract Background Enriching the soil with organic matter such as humic and fulvic acid to increase its content available nutrients, improves the chemical properties of the soil and increases plant growth as well as grain yield. In this study, we conducted a field experiment using humic acid (HA), fulvic acid (FA) and recommended dose (RDP) of phosphorus fertilizer to treat Hordeum vulgare seedling, in which four concentrations from HA, FA and RDP (0.0 %, 50 %, 75 % and 100%) under saline soil conditions . Moreover, some agronomic traits (e.g. grain yield, straw yield, spikes weight, plant height, spike length and spike weight) in barley seedling after treated with different concentrations from HA, FA and RDP were determined. As such the beneficial effects of these combinations to improve plant growth, N, P, and K uptake, grain yield, and its components under salinity stress were assessed. Results The findings showed that the treatments HA + 100% RDP (T1), HA + 75% RDP (T2), FA + 100% RDP (T5), HA + 50% RDP (T3), and FA + 75% RDP (T6), improved number of spikes/plant, 1000-grain weight, grain yield/ha, harvest index, the amount of uptake of nitrogen (N), phosphorous (P) and potassium (K) in straw and grain. The increase for grain yield over the control was 64.69, 56.77, 49.83, 49.17, and 44.22% in the first season, and 64.08, 56.63, 49.19, 48.87, and 43.69% in the second season,. Meanwhile, the increase for grain yield when compared to the recommended dose was 22.30, 16.42, 11.27, 10.78, and 7.11% in the first season, and 22.17, 16.63, 11.08, 10.84, and 6.99% in the second season. Therefore, under salinity conditions the best results were obtained when, in addition to phosphate fertilizer, the soil was treated with humic acid or foliar application the plants with fulvic acid under one of the following treatments: HA + 100% RDP (T1), HA + 75% RDP (T2), FA + 100% RDP (T5), HA + 50% RDP (T3), and FA + 75% RDP (T6). Conclusions The result of the use of organic amendments was an increase in the tolerance of barley plant to salinity stress, which was evident from the improvement in the different traits that occurred after the treatment using treatments that included organic amendments (humic acid or fulvic acid).

Bio-fertilizers are the most important and effective method used to reduce the quantities of chemical fertilizers consumed and reduce dependence on them in agricultural production to avoid their harmful effects on the environment and public health as well as reduce the cost of agricultural production in light of increasing pollution and under adverse conditions for production and climate change. A bio-fertilizer depends primarily on the use of beneficial microorganisms such as arbuscular mycorrhizal fungi (AMF) to improve the uptake of nutrients, improve plant growth, productivity, and grain yield. Crop production faces many challenges, and drought is one of the majority of the significant factors limiting crop production worldwide, especially in semi-arid regions. The objective of this study was to evaluate the effects of AMF and phosphate solubilizing bacteria (PSB), plus three rates of the recommended dose of phosphorus (RDP) fertilizer on yield, yield components, and nutrients uptake, in addition to evaluating the beneficial effects of these combinations to develop Phosphorus (P) management under three levels of irrigation water, i.e., three irrigations (normal or well-watered), two irrigations (moderate drought), and one irrigation (severe drought) on barley (Hordeum vulgare L.). The results showed that the treatment with AMF bio-fertilizer yielded the highest values of plant height, spike length, spike weight, number of grains/spike, 1000-grain weight, grain yield, straw yield, biological yield, and harvest index. Moreover, the grain and straw uptake of nitrogen (N), P, and potassium (K) (kg ha−1) in the two seasons under the three levels of irrigation, respectively, were superior followed by the inoculation by PSB. While the treatment without bio-fertilizer yielded the lowest values of these traits of barley, the treatment with bio-fertilizer yielded the increased percentage of the grain yield by 17.27%, 17.33% with applying AMF, and 10.31%, 10.40% with treatment by PSB. Treatment with AMF or PSB (Phosphorien), plus rates of phosphorus fertilizer under conditions of irrigation water shortage, whether irrigation was performed once or twice, led to an increase in grain yield and other characteristics compared to the same fertilization rates without inoculation. The results of this study showed that the use of bio-fertilizers led to an increase in plant tolerance to drought stress, and this was demonstrated by an increase in various traits with the use of treatments that include bio-fertilizers. Therefore, it is suggested to inoculate the seeds with AMF or PSB plus adding phosphate fertilizers at the recommended dose under drought conditions.

High temperatures in late spring, summer, and autumn are one of the main elements limiting cucumber production. Heat stress in cucumber plants leads to significant changes in sex expression and negative effects at the physiological stage, including decreased absorption of water and nutrients, decreased photosynthetic functions, and increased respiration, which in turn affects growth and production. Therefore, it is very difficult for cucumber plants exposed to heat stress to improve their productivity, especially in arid and semi-arid regions. Cucumber plants bear a variety of flower forms, including staminate, pistillate, and hermaphrodites that occur in different arrangements. In addition, maleness is considered the main problem in cucumber production, as it significantly reduces fruit yield. Recently, the growth, flowering, and productivity of plants have been controlled with the help of growth-regulating substances, and one of these substances is naphthalene acetic acid (NAA), which is of great importance in modifying sex in cucumber and various cucurbit crops. Two experiments were conducted during 2022 and 2023 during the summer season to study the effect of foliar spraying of two levels of potassium nitrate, 500 mg/L and 1000 mg/L, and two levels of NAA, 50 mg/L and 100 mg/L, individually and together, and the comparison treatment in nine treatments on growth traits, sex ratio, fruit traits and yield of cucumber (Cucumis sativas L.) plants in three replicates in a completely randomized block design. The results indicated that applying the treatment containing 1000 mg/L KNO3 + 100 mg/L NAA led to obtaining the highest value in most vegetable growth, flowering, and production parameters, with a significant increase compared to the control and all other treatments. Followed by treatments consisting of potassium nitrate and NAA, which gave high values in the traits of sex ratio %, fruit setting %, fruit yield, and most other traits. This study showed the importance of spraying with both NAA and potassium nitrate, individually or in combination, and the high combined effect of both in the treatments that contained each of them in the vegetative growth traits and floral traits such as the number of female flowers, the sexual ratio, fruit set percentage, weight fruit, length fruit, and the fruit yield in cucumber plants grown in the summer season with high temperatures

The water-retaining and yield-increasing capacity of super-absorbent polymer (SAP) are essential for soil remediation in arid and semi-arid areas. Water availability is an increasing challenge to plant development and crop yield. During the growing seasons in 2021 and 2022, the present study was conducted to evaluate the effect of the addition of different amounts of SAP on the development and yield of green beans (Phaseolus vulgaris L. cv Bronco) under varying water deficit stresses, compared with the control treatment without SAP and water deficit stress. The results demonstrated that a 50% reduction in water requirement (WR) resulted in significant decreases in leaf fresh weight, specific leaf area, leaf total chlorophyll content, pod number, leaf free water content, pod fresh weight per plant, and yield. Decreases were also found in pod total chlorophyll content, carotenoids, dry matter and total protein, leaf proline content, and crude fiber content. Additionally, leaf water saturation deficit was significantly increased under the stress compared with the full irrigation at 100% WR. However, irrigation at 75% WR increased pod contents of ascorbic acid, total sugars, and leaf bound water. The current study also indicated that addition of SAP significantly enhanced the above-mentioned growth characteristics under irrigation at 50% and 75% WR. Treatment with SAP at 3 g/plant was the most effective in mitigating the adverse effects of water deficiency, especially at the irrigation rate of 75% WR. Pearson’s correlation analysis showed significantly positive correlations between the growth parameters, as well as pod yield, under water stress and SAP. This study provides a promising strategy for green bean cultivation by adding SAP to soil to alleviate water shortage stress.

Under salinity conditions, growth and productivity of grain crops decrease, leading to inhibition and limited absorption of water and elements necessary for plant growth, osmotic imbalance, ionic stress, and oxidative stress. Microorganisms in bio-fertilizers have several mechanisms to provide benefits to crop plants and reduce the harmful effect of salinity. They can be effective in dissolving phosphate, fixing nitrogen, promoting plant growth, and can have a combination of all these qualities. During two successful agricultural seasons, two field experiments were conducted to evaluate the effect of bio-fertilizer applications, including phosphate solubilizing bacteria (PSB), nitrogen fixation bacteria and a mix of phosphate-solubilizing bacteria and nitrogen fixation bacteria with three rates, 50, 75 and 100% NPK, of the recommended dose of minimal fertilizer on agronomic traits, yield and nutrient uptake of barley (Hordeum vulgare) under saline condition in Village 13, Farafra Oasis, New Valley Governorate, Egypt. The results showed that the application of Microbein + 75% NPK recorded the highest values of plant height, spike length, number of spikes/m2, grain yield (Mg ha−1), straw yield (Mg ha−1), biological yield (Mg ha−1), protein content %, nitrogen (N), phosphorus (P), potassium (K) uptakes in grain and straw (kg ha−1), available nitrogen (mg/kg soil), available phosphorus (mg/kg soil), total microbial count of soil, antioxidant activity of soil (AOA), dehydrogenase, nitrogen fixers, and PSB counts. The application of bio-fertilizers led to an increase in plant tolerance to salt stress, plant growth, grain yield, and straw yield, in addition to the application of the bio-fertilizers, which resulted in a 25% saving in the cost of mineral fertilizers used in barley production.

The CCR7 chemokine axis is comprised of chemokine ligand 21 (CCL21) and chemokine ligand 19 (CCL19) acting on chemokine receptor 7 (CCR7). This axis plays two important but apparently opposing roles in cancer. On the one hand, this axis is significantly engaged in the trafficking of a number of effecter cells involved in mounting an immune response to a growing tumour. This suggests therapeutic strategies which involve potentiation of this axis can be used to combat the spread of cancer. On the other hand, the CCR7 axis plays a significant role in controlling the migration of tumour cells towards the lymphatic system and metastasis and can thus contribute to the expansion of cancer. This implies that therapeutic strategies which involve decreasing signaling through the CCR7 axis would have a beneficial effect in preventing dissemination of cancer. This dichotomy has partly been the reason why this axis has not yet been exploited, as other chemokine axes have, as a therapeutic target in cancer. Recent report of a crystal structure for CCR7 provides opportunities to exploit this axis in developing new cancer therapies. However, it remains unclear which of these two strategies, potentiation or antagonism of the CCR7 axis, is more appropriate for cancer therapy. This review brings together the evidence supporting both roles of the CCR7 axis in cancer and examines the future potential of each of the two different therapeutic approaches involving the CCR7 axis in cancer., (Copyright © 2020. Published by Elsevier B.V.)