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Plant growth-promoting bacteria (PGPB) play an important role in improving agricultural production under several abiotic stress factors. PGPB can be used to increase crop growth and development through hormonal balance and increase nutrient uptake. The positive effect of PGPB may be due to its pivotal role in morphophysiological and biochemical characteristics like leaf number, leaf area, and stem length. Furthermore, relative water content, chlorophyll content, carotenoids, antioxidant enzymes, and plant hormones were improved with PGPB treatment. Crop yield and yield components were also increased with PGPB treatment in numerous crops. The anatomical structure of plant organs was increased such as lamina thickness, stem diameter, xylem vessel diameter, and number of xylem vessels as well as phloem thickness under treatment with PGPB. Additionally, PGPB can alleviate the negative effects of several abiotic stresses by regulating the antioxidant defense system to scavenge the reactive oxygen species resulting in an improvement of yield production in the stressed plants. Additionally, gene expressions were controlled by calcium ion modulation during secondary messengers that act upon calcium-dependent protein kinase and protein phosphatases. This includes many transcription factors such as MYB, AP2/ERF, bZIP, and NAC which regulate genes related to salinity stress signals. PGPB can demonstrate induction genes of signaling under abiotic stress conditions. This review gives an outline of the PGPB role in alleviating the harmful effects of abiotic factors such as salinity, drought, and heat associated with the improvement of the morpho-physiological and biochemical features especially, leaves and branches number, leaf area, antioxidant compounds, plant hormones, and relative water content. [ABSTRACT FROM AUTHOR]

Salinity is a significant abiotic stress that has a profound effect on growth, the content of secondary products, and the genotoxicity of cells. Lime, Citrus aurantifolia, is a popular plant belonging to the family Rutaceae. The interest in cultivating this plant is due to the importance of its volatile oil, which is included in many pharmaceutical industries, but C. aurantifolia plants are affected by the NaCl salinity levels. In the present study, a comet assay test has been applied to evaluate the genotoxic impact of salinity at 0, 50, 100, and 200mM of NaCl on C. aurantifolia tissue-cultured plants. Furthermore, terpene gene expression was investigated using a semi-quantitative real-time polymerase chain reaction. Results from the two analyses revealed that 200 mM of NaCl stress resulted in high levels of severe damage to the C. aurantifolia plants' DNA tail 21.8%, tail length 6.56 µm, and tail moment 3.19 Unit. The relative highest expression of RtHK and TAT genes was 2.08, and 1.693, respectively, when plants were exposed to 200 mM of NaCl, whereas pv4CL2RT expressed 1.50 in plants subjected to 100 mM of NaCl. The accumulation of transcripts for the RTMYB was 0.951 when plants were treated with NaCl at 50 mM, and RtGPPS gene was significantly decreased to 0.446 during saline exposure at 100 mM. We conclude that the comet assay test offers an appropriate tool to detect DNA damage as well as RtHK, TAT, and pv4CL2RT genes having post-transcriptional regulation in C. aurantifolia plant cells under salinity stress. Future studies are needed to assess the application of gene expression and comet assay technologies using another set of genes that show vulnerability to different stresses on lime and other plants. [ABSTRACT FROM AUTHOR]

Recently, the use of nanofertilizers has received a great deal of attention in managing plants under biotic and abiotic stresses. However, studies that elucidate the role of silicon dioxide nanoparticles (SiO2NPs) in regulating maize tolerance to drought stress are still at early stages of development. In this study, plants that were treated with SiO2NPs (0.25 g/L as foliar spray) displayed considerable improvement in the growth indices, despite being subjected to drought stress. In addition, the action of SiO2NPs led to a considerable rise in the levels of chlorophylls, proline, cell membrane integrity, leaf water content, and antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT), and guaiacol peroxidase (G-POX)). In contrast, an inverse trend was seen in the oxidative injury, the total amount of soluble sugars, and the activity of ascorbate peroxidase (APX). At the same time, carotenoids were unaffected in SiO2NPs-treated and non-treated plants under drought stress. The results of the molecular investigation that was conducted using qRT-PCR showed that the relative expression of the D2 protein of photosystem II (PsbD) was elevated in SiO2NPs-treated plants in response to drought stress, while the expression of the osmotic-like protein (OSM-34) and aquaporin (AQPs) was downregulated in SiO2NPs-treated plants in response to drought stress. This research could pave the way for further investigations into how SiO2NPs boost plant resistance to drought stress. [ABSTRACT FROM AUTHOR]

Biotransformation plays a significant role in sustainable agriculture. This process involves utilizing microorganisms, such as bacteria and fungi, to transform organic compounds and metabolites into bioactive compounds which have beneficial effects on plant growth, yield, and soil characters. Accordingly, the present study aims to explore the role of biotransformation of Acacia nilotica metabolites by Aspergillus subolivaceus in boosting L. termis yield, as an important strategy in agricultural sustainability. A pilot experiment was performed on five fungal strains (Fusarium oxysporium A. aculeatus, Aspergillus. subolivaceus, Rhizopus oryzae and Trichoderma viride) which were grown on different parts of plants (A. nilotica leaves; green tea leaves, green pepper fruits and pomegranate fruits), and the results indicated that the most active metabolite for the growth of L. termis seeds was the fungal metabolite of A. subolivaceus growing on A. nilotica. More specifically, we assess how metabolites produced by Aspergillus subolivaceus using A. nilotica leaves affect the biochemical properties and chemical composition of L. termis seeds. A. subolivaceus was grown on leaves from A. nilotica to obtain metabolites and fractionated into four extracts. Two concentrations of each extract were examined by pretreating the seeds of L. termis. The study found that all four extracts contributed to an increase in yield and some biochemical properties of the yielded seeds. The best results were obtained by treating the L. termis seeds with an extract obtained from diethyl ether, which led to a significant increase in total nitrogen, amino nitrogen, glucose and protein contents of the seeds. According to 1H NMR guided GC/MS analysis, our results showed an increase in phytochemicals such as terpenes, fatty materials, and flavonoids including 3′,4′,7-trimethoxyquercetin and 4-methyl-p-menth-8-en-3-one, which have not been stated before from A. nilotica suggesting that biotransformation may have occurred due to the presence of A. subolivaceus. [ABSTRACT FROM AUTHOR]

Fusarium oxysporum is one of the most harmful soil-borne pathogens that cause root rot, damping-off, and wilt disease in many plant species. Management of Fusarium oxysporum diseases is often by using many harmful and expensive chemical fungicides which have many harmful effects on the environment and human health. The current study was conducted to identify the chemical constituents of black cumin seeds' methanolic extract and investigate the ability of the major constituents to inhibit the Fusarium oxysporum trypsin-like serine protease, which play an important role in F. oxysporun pathogenicity. The HPLC-MS analysis of black cumin seeds' methanolic extract revealed the presence of seven major compounds: amentoflavone, Procyanidin C2, Quercetin3-O-sophoroside-7-O-rhamnoside, 5,7-Dihydroxy-3,4-dimethoxyflavone, Borapetoside A, tetrahydroxy-urs-12-en-28-O-[b-D-glucopyranosyl (1-2)-b-D-glucopyranosyl] ester, and kudzusapongenol A-hexA-pen. The results of molecular docking between these compounds and the active site of Fusarium oxysporium trypsin showed that only four compounds were able to bind to the active site of F. oxysporum trypsin. Amentoflavone, 5,7-Dihydroxy-3,4-dimethoxyflavone, and Quercetin3-O-sophoroside-7-O-rhamnoside have the highest binding energy, −6.4, −6.5, and −6.5 Kcal/mol, respectively. In addition, the results clarify that 5,7-Dihydroxy-3,4-dimethoxyflavone was the only compound to form a hydrogen bond with Asp189 (the residue responsible for substrate specificity). The results of the study strongly indicate that flavonoids of black cumin seeds' methanolic extract could be used as effective inhibitors for the F. oxysporum trypsin-like serine protease. [ABSTRACT FROM AUTHOR]

A collection of twenty-one bread wheat genotypes consisted of 10 lines from CIMMYT and 11 advanced lines from our breeding programs were evaluated under different watering regimes in comparison with four commercial cultivars during 2017/18 and 2018/19 seasons. Normal, two and one irrigation treatments were used. Heading date, plant height, number of spikes m-2, 1000-kernel weight and grain yield m-2 were studied. The reduced irrigation decreased significantly all the studied traits. There were significant variations among the studied genotypes. Mean squares due seasons × genotypes, interaction was significant for most traits, indicating that response of the studied genotypes varied from season to another. Line 6, Line 20, Line 19 and Line 13 could be introduced for advanced evaluation on the national level to confirm the present results. In addition, it's could be used to enhance wheat breeding for water stress tolerance. Misr 1, Gemmeiza 12 and Giza 171 cultivars tend to tolerate reduced irrigation regimes. [ABSTRACT FROM AUTHOR]

The current study was designed to investigate the effects of the magnetically treated saline water technique and different socking times on seed germination, growth performance, yield, and production of cucumbers. Magnetically treated saline water (at 14500 gausses) was used compared with non-magnetic water for experimental seeds, which were treated with four different stocking periods: fast, 2, 4, and 6 hours. Three experiments were carried out under plastic greenhouse conditions at different growing stages. The results indicated that soaking the seeds in magnetized water resulted in increased germination percentage and reduced the required time for seed germination compared with non-magnetized water. Using magnetic water enhanced seedling growth parameters, i.e., number of leaves, length, diameter, root length, and chlorophyll. Magnetic water led to early flowering compared to nonmagnetic saline water, where the control treatment delayed flowering. Significant increases in fruit length, diameter, and weight were detected, resulting in increased production of cucumbers when magnetized water was used. Furthermore, the nutrient content (N, P, K and Ca) in leaves significantly increased in the plants magnetically treated saline water more than untreated control. On the contrary, the highest concentrations of Na and Cl in plant leaves were found in untreated plants. In conclusion, soaking cucumber seeds in magnetized water for 2 hours and using magnetized irrigation water during growing seasons enhanced germination rate, growth, and yield under salinity conditions. [ABSTRACT FROM AUTHOR]

Mango fruits sourced from tropical yields have had a high commercial comeback from being viewed as susceptible to chilling injury under long storage durations. When the fruits are exposed to cold storage, this results in physiological changes due to the side effects of the storage on the fruits, expanding the rates of loss during the period between harvest and marketing. It is difficult to harvest mangoes as the fruits show varying maturities and are located in different positions on the trees. The purpose of this study was to test the idea that fruits' location on the tree influences how the fruit behaves during cold storage. During two seasons (2019–2020), the impact of on-tree fruit location, i.e., sunny side (SUN; fruit exposed to the sun for most of the day), shade (SHA; fruit grown on the shady side of trees), and inside the canopy (INS; fruit grown inside the tree canopy), on the chilling sensitivity and the activities of antioxidant enzymes of 'Zibda' mangos stored at a low temperature (4 ± 1 °C) for 35 days was determined. In contrast to SHA and SUN mangos, INS fruits were shown to be progressively tolerant to low storage temperatures. These fruits also showed the highest activities of ascorbate peroxidase (APX), peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD). In addition, the contents of O2− and H2O2 decreased in INS fruit during storage. Consequently, the cell membrane compartments were maintained, showing low accumulation of both malondialdehyde (MDA) and the protein carbonyl group (PCG) during storage. These results indicate that the fruit positions can also be considered at the time of harvesting for the classification of fruits before cold storage. This classification can also be added to the mango trading protocol to minimize the loss of economic returns by chilling injury. [ABSTRACT FROM AUTHOR]

Caraway plants have been known as a rich source of phytochemicals, such as flavonoids, monoterpenoid glucosides and alkaloids. In this regard, the application of elevated CO2 (eCO2) as a bio-enhancer for increasing plant growth and phytochemical content has been the focus of many studies; however, the interaction between eCO2 and plants at different developmental stages has not been extensively explored. Thus, the present study aimed at investigating the changes in growth, photosynthesis and phytochemicals of caraway plants at two developmental stages (sprouts and mature tissues) under control and increased CO2 conditions (ambient CO2 (a CO2, 400 ± 27 μmol CO2 mol−1 air) and eCO2, 620 ± 42 μmol CO2 mol−1 air ppm). Moreover, we evaluated the impact of eCO2-induced changes in plant metabolites on the antioxidant and antibacterial activities of caraway sprouts and mature plants. CO2 enrichment increased photosynthesis and biomass accumulation of both caraway stages. Regarding their phytochemical contents, caraway plants interacted differently with eCO2, depending on their developmental stages. High levels of CO2 enhanced the production of total nutrients, i.e., carbohydrates, proteins, fats and crude fibers, as well as organic and amino acids, in an equal pattern in both caraway sprouts and mature plants. Interestingly, the eCO2-induced effect on minerals, vitamins and phenolics was more pronounced in caraway sprouts than the mature tissues. Furthermore, the antioxidant and antibacterial activities of caraway plants were enhanced under eCO2 treatment, particularly at the mature stage. Overall, eCO2 provoked changes in the phytochemical contents of caraway plants, particularly at the sprouting stage and, hence, improved their nutritive and health-promoting properties. [ABSTRACT FROM AUTHOR]

Tetranychus urticae is a critical pest affecting the quality and quantity of the yield under cover and in open ground. Its pesticide resistance and short life cycle leads to rapidly spreading. The present study evaluated the efficacy of essential oils (EOs) of caraway, lemon, mint and peppermint against adult and egg stages of two spotted spider mite T. urticae, compared to that of the recommended acaricide, abamectin. Abamectin is a recommended acaricide by the Agricultural Pesticide Committee. Our results proved that, the efficacy of the EOs was lower than the acaricide, abamectin showed the highest effect on the egg deposition (46.66 % reduction), and egg hatchability (47.91%), comparable to the control treatment (the leaves discs without treatments). However, peppermint oil had the least effect on the egg deposition (25% reduction), and egg hatchability (53.3%). Caraway, lemon and mint oils showed moderate impact on the egg hatchability and deposition. Toxicity of different compounds to eggs of T. urticae showed that Abamectin was the most effective however peppermint oil recorded the lowest effect. There for essential oils can be used in integrated best management programs to control T. urticae. [ABSTRACT FROM AUTHOR]