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Background: Temperature remarkably affects the growth and metabolism of plants. Tobacco is an important cash crop, and the long-term effects of different growth temperatures (18.5, 23.5 and 28.5 °C, daily average) on growth, development and plastid pigments metabolism of tobacco plants were investigated in this study., Results: Compared with tobacco plants grown under 23.5 °C, treatments with 18.5 and 28.5 °C inhibited the expansion of leaves. The contents of superoxide anion (O 2 ·- ), hydrogen peroxide (H 2 O 2 ) and malonaldehyde (MDA) in the leaves were significantly increased under 28.5 °C from 0 to 60 days, which in turn accelerated the flowering and senescence of tobacco plants. By contrast, the treatment with 18.5 °C remarkably decreased O 2 .- , H 2 O 2 and MDA, and delayed the flowering and senescence. Furthermore, treatment with 18.5 °C significantly up-regulated the expression of glutamyl-tRNA reductase (Glu-TR) and magnesium chelatase (MgCH), and down-regulated the ferri chelatase (FeCH), protochlorophyllide oxidoreductase, chlorophyllase (CHLase), phaeophorbide a monooxygenase (PaO) and phytoene synthase (PSY), which further promoted the accumulation of chlorophyll (Chls) and reduced the carotenoids (Cars) in leaves. On the contrary, exposing to 28.5 °C remarkably down-regulated the Glu-TR and MgCH, and up-regulated the FeCH, CHLase, PaO and PSY, which in turn decreased the Chls and increased the Cars in tobacco leaves., Conclusion: As compared with the plants grown under 23.5 °C, lower (18.5 °C) and higher (28.5 °C) growth temperature inhibited the growth of tobacco plants. In general, treatment with 28.5 °C accelerated the flowering and senescence of tobacco plants by enhancing the accumulation of O 2 .- and H 2 O 2 in leaves, while exposing to 18.5 °C had the opposite effects. Treatment with 18.5 °C increased the content of Chls and reduced the Cars in leaves. In contrast, Treatment with 28.5 °C decreased the Chls and increased the Cars. Moreover, both O 2 .- and H 2 O 2 took part in the breakdown of Chls in tobacco leaves to some extent. The results suggest that growth temperature could regulate growth, development, and plastid pigments metabolism, and 23.5 °C could be an optimal temperature for growth, development and metabolism of plastid pigments of tobacco plants under the experimental conditions.

Titanium and its alloys exhibit a favorable integration of characteristics, including notable strength and high resistance to corrosion. However, they are deficient in terms of wear resistance and thermal conductivity, among other properties. The aforementioned limitations impose constraints on the utilization of these alloys across diverse applications. Currently, various strategies involving the utilization of composite materials are being implemented in order to address and mitigate these previously mentioned limitations. The utilization of micro- or nano-sized reinforcements has been employed to improve the characteristics of the metal matrix. Diverse techniques are employed to uniformly distribute the reinforcement within the matrix, thereby generating titanium metal matrix composites (TMCs). The use of TMCs has become increasingly prevalent in diverse sectors, including defense, automotive, aerospace, and biomedical, owing to their remarkable characteristics, which encompass lower weight, higher specific strength, and compatibility with biological systems. The present study discusses various manufacturing techniques, including spark plasma sintering (SPS), additive manufacturing, and vacuum melting. This study further examines different reinforcements that are considered in the production of TMCs. The current study also investigates the effects of reinforcements on properties such as mechanical and tribological characteristics. The study demonstrated that the incorporation of reinforcements resulted in enhanced properties. [ABSTRACT FROM AUTHOR]

Maize production and productivity are affected by drought stress in tropical and subtropical ecologies, as the majority of the area under maize cultivation in these ecologies is rain-fed. The present investigation was conducted to study the physiological and biochemical effects of 24-Epibrassinolide (EBR) as a plant hormone on drought tolerance in maize. Two maize hybrids, Vivek hybrid 9 and Bio 9637, were grown under three different conditions: (i) irrigated, (ii) drought, and (iii) drought+EBR. A total of 2 weeks before the anthesis, irrigation was discontinued to produce a drought-like condition. In the drought+EBR treatment group, irrigation was also stopped, and in addition, EBR was applied as a foliar spray on the same day in the drought plots. It was observed that drought had a major influence on the photosynthesis rate, membrane stability index, leaf area index, relative water content, and leaf water potential; this effect was more pronounced in Bio 9637. Conversely, the activities of antioxidant enzymes such as catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) increased in both hybrids under drought conditions. Specifically, Vivek hybrid 9 showed 74% higher CAT activity under drought conditions as compared to the control. Additionally, EBR application further enhanced the activity of this enzyme by 23% compared to plants under drought conditions. Both hybrids experienced a significant reduction in plant girth due to drought stress. However, it was found that exogenously applying EBR reduced the detrimental effects of drought stress on the plant, and this effect was more pronounced in Bio 9637. In fact, Bio 9637 treated with EBR showed an 86% increase in proline content and a 70% increase in glycine betaine content compared to untreated plants under drought conditions. Taken together, our results suggested EBR enhanced tolerance to drought in maize hybrids. Hence, pre-anthesis foliar application of EBR might partly overcome the adverse effects of flowering stage drought in maize. [ABSTRACT FROM AUTHOR]

One of the most serious ecological problems affecting drylands worldwide is sandification, due to exacerbation of the desertification process. As sandified land grows larger, the potential for agriculture decreases. Particularly in Pakistan, desertification is also a significant issue, with numerous natural and human-caused contributors. Desertification often occurs in Pakistan's south Punjab's dry lands, and regularly monitoring the area's sandification dynamics can assist in mitigating the problem. The purpose of this study is to determine the sensitivity to the sandification phenomenon in South Punjab drylands (Rajanpur, Rahim Yar Khan, and Bahawalpur) Pakistan. ALOS PALSAR DEM of 12.5 m resolution and Level 2 Landsat 5, 7, and 8 data (1988, 2001, and 2018) were utilized to conduct this research. The sensitivity to sandification was determined using land use land cover (LULC), slope, and aspect as the determining variables. These variables were separately integrated into ArcGIS using the weighted sum approach for the years 1988, 2001, and 2018. The analysis of sensitivity to sandification found that insensitive land expanded by 47 percent between 1988 and 2018, whereas very low sensitive and low sensitive classifications declined by -5.95 percent and -9.23 percent, respectively. The moderately sensitive area to sandification saw the largest percentage change between 1988 and 2018, changing by 1095.52%. The desertified land saw the second-largest percentage change, changing by 521.58%. However, the highly sensitive to sandification class showed the greatest percentage decrease (-53.65%). The most significant factor found to have an impact on the local sandification dynamics was LULC. By continuously monitoring the dynamics of sandification, the region's desertification intensity can be reduced. A Decision Support System (DSS) can be developed for this purpose through further study. Policymakers can use the DSS findings to assist them in creating strategies for reducing desertification in this region. [ABSTRACT FROM AUTHOR]

Background: Paclobutrazol is widely used in the agricultural field. This study investigated the effects of seed priming with different concentrations of paclobutrazol on seedling quality, 2-acetyl-1-pyrroline (2-AP, a key aroma component of fragrant rice) biosynthesis, and related physiological and biochemical indicators in fragrant rice seedlings. Results: The experiment is being conducted at the College of Agriculture, South China Agricultural University. In the experiment, three concentrations of paclobutrazol (Pac 1: 20 mg·L−1; Pac 2: 40 mg·L−1; Pac 3: 80 mg·L−1) were used to initiate the treatment of fragrant rice seeds, while water treatment was used as a control (CK). The results showed that compared with CK, paclobutrazol treatment reduced plant height, increased stem diameter, and increased fresh and dry weight of aromatic rice seedlings. Moreover, paclobutrazol treatment also increased the seedlings' photosynthetic pigment content and net photosynthetic rate. Conclusions: This study demonstrates that paclobutrazol primarily increases the content of proline by reducing the content of glutamate and down-regulating the expression of P5CS2, thereby promoting the conversion of proline to the aromatic substance 2-AP. Under the appropriate concentration of paclobutrazol (40 mg·L−1~80 mg·L−1), the seedling quality, stress resistance, and aroma of fragrant rice can be improved. [ABSTRACT FROM AUTHOR]

Inadequate management of nitrogen fertilization, due to high costs, compromises the nutrition and productivity of winter forage plants, highlighting the need to adopt sustainable alternatives, such as using nitrogen-fixing bacteria. This research evaluated the growth promotion of black oat (Avena strigosa) and ryegrass (Lolium multiflorum) plants inoculated with Azospirillum brasilense rhizobacteria. The experiments were carried out over two consecutive harvests in Santa Maria, Brazil. The sowing density was 300 viable seeds per square meter for black oats and 100 viable seeds per square meter for ryegrass. A dose of 5 ml per kg of seeds from the consortium was used as an inoculant. Following sowing, the seeds were incorporated into the soil through light harrowing. At the beginning of tillering, 50 kg of N ha-1 was applied to create treatments with and without nitrogen. Plant emergence, plant height, number of leaves and tillers were evaluated. In the first year, an inoculation response was observed for the number of black oat plants emerged m-2. In the second year (corn residue), an inoculation response was observed for the number of leaves and height of black oats. Under soybean straw for oat leaf number and ryegrass tiller number. The current research highlights the effectiveness of inoculation with Azospirillum brasilense in promoting significant improvements in the morphological components of forage crops. Following corn, an increase in the number of leaves and tillers was observed, as well as in the height of black oats. Similarly, following soybeans, there was an increase in the number of black oat tillers and the number of ryegrass leaves. The results emphasize the importance of inoculation as an effective practice to enhance crop development and performance in agricultural systems, improving sustainability and productivity under soybean and corn residues. [ABSTRACT FROM AUTHOR]

Titanium matrix composites (TMCs) have garnered substantial attention from researchers owing to their outstanding properties. Nonetheless, the strength and ductility of TMCs hardly co-exist and often show a trade-off between each other. In this study, we employ an ultra-thin graphite powder sheet as the carbon source and employ Ti/C composites with varying carbon contents, prepared via a layer-stacked laminated sintering method, to ensure a comprehensive in-situ reaction and uniform reinforcement distribution. With increasing carbon content, noticeable alterations occur in the size, concentration, and morphology of the titanium carbide (TiC) particles. The increase of TiC particle content is found to boost the ultimate tensile strength of the composite. However, this improvement comes at the expense of reduced elongation. Notably, as the carbon content reaches 1.81 wt%, the yield strength and ultimate tensile strength of the composites soar to 354.4 MPa and 575.4 MPa, respectively. These values represent a remarkable increase of 75.4% and 65.0% compared to pure titanium, while maintaining an acceptable elongation of 6.45%. This study unveils a promising approach for significantly enhancing the mechanical properties of titanium alloys. [ABSTRACT FROM AUTHOR]

The purpose of this study is to evaluate the desertification vulnerability and the future trends of desertification expansion in the Bahawalpur division of Punjab, Pakistan. This aim is achieved by analyzing Landsat data between the years 1990 and 2019. The biophysical index and socio-economic index were used to identify the Desertification Vulnerability Index (DVI) and its changes which have taken place over the study period between the years 1990 and 2019. The findings indicated that there was a decrease in the rate of desertification vulnerability from 1990 to 2019. In addition, the central and southern part of the Bahawalpur division is classified as a highly vulnerable zone in comparison to the other part of the region. The overall results show that the barren land and the desert area have been showing a decreasing trend, accompanied by substantial growth in vegetation from 1990 to 2019. The findings of the DVI analysis indicate that the Highly Vulnerable Area has decreased spatially from 61.12 in 1990 to 55.3% in 2019, while the Moderately Vulnerable Area and the Least Vulnerable Area have grown from 25.59% and 17.2% in 1990 to 28.56 and 19.53% in 2019, respectively. The decreasing trend demonstrates the effectiveness of efforts to combat desertification and the government could develop the best strategies for rehabilitation works and control the land degradation process in the most vulnerable areas in the Bahawalpur division of Punjab, Pakistan. [ABSTRACT FROM AUTHOR]

CaAl12O19–CaTiO3 (CA6–CT) materials are fabricated using a solid sintering method to investigate the effects of TiO2 content on the phase composition, properties, and microstructure of the materials. With increasing TiO2 content, the preferential replacement of Al3+ by Ti4+ in the CA6 crystal increases the concentration of vacancy defects, thereby promoting ion diffusion and mass transfer, which improves the sintering reaction activity. However, as more TiO2 is added, the CaTiO3 phase formed increases the thermal conductivity and mean expansion coefficient of the material at high temperatures, which degrades its thermal shock stability. The CA6–CT refractory showed good corrosion resistance to the Ti6Al4V melt. Except for a slight penetration of iron element, no obvious corrosion occurred at the reaction interface. [ABSTRACT FROM AUTHOR]

Climate change has exacerbated the effects of abiotic stresses on plant growth and productivity. Drought is one of the most important abiotic stress factors that interfere with plant growth and development. Plant selection and breeding as well as genetic engineering methods used to improve crop drought tolerance are expensive and time consuming. Plants use a myriad of adaptative mechanisms to cope with the adverse effects of drought stress including the association with beneficial microorganisms such as plant growth promoting rhizobacteria (PGPR). Inoculation of plant roots with different PGPR species has been shown to promote drought tolerance through a variety of interconnected physiological, biochemical, molecular, nutritional, metabolic, and cellular processes, which include enhanced plant growth, root elongation, phytohormone production or inhibition, and production of volatile organic compounds. Therefore, plant colonization by PGPR is an eco-friendly agricultural method to improve plant growth and productivity. Notably, the processes regulated and enhanced by PGPR can promote plant growth as well as enhance drought tolerance. This review addresses the current knowledge on how drought stress affects plant growth and development and describes how PGPR can trigger plant drought stress responses at the physiological, morphological, and molecular levels. Highlight: This review aims to highlight the recent advances in understanding the effects of plant growth-promoting rhizobacteria in enhancing plant growth and drought stress tolerance. [ABSTRACT FROM AUTHOR]

Engineered nanosystems offer a promising strategy for macrophage-targeted therapies for various diseases, and their physicochemical parameters including surface-active ligands, size and shape are widely investigated for improving their therapeutic efficacy. However, little is known about the synergistic effect of elasticity and surface-active ligands. Here, two kinds of anti-inflammatory N-acetylcysteine (NAC)-loaded macrophage-targeting apoptotic-cell-inspired phosphatidylserine (PS)-containing nano-liposomes (PSLipos) were constructed, which had similar size and morphology but different Young's modulus (E) (H, ~ 100 kPa > Emacrophage vs. L, ~ 2 kPa < Emacrophage). Interestingly, these PSLipos-NAC showed similar drug loading and encapsulation efficiency, and in vitro slow-release behavior of NAC, but modulus-dependent interactions with macrophages. Softer PSLipos-L-NAC could resist macrophage capture, but remarkably prolong their targeting effect period on macrophages via durable binding to macrophage surface, and subsequently more effectively suppress inflammatory response in macrophages and then hasten inflammatory lung epithelial cell wound healing. Especially, pulmonary administration of PSLipos-L-NAC could significantly reduce the inflammatory response of M1-like macrophages in lung tissue and promote lung injury repair in a bleomycin-induced acute lung injury (ALI) mouse model, providing a potential therapeutic approach for ALI. The results strongly suggest that softness may enhance ligand-directed macrophage-mediated therapeutic efficacy of nanosystems, which will shed new light on the design of engineered nanotherapeutics. [ABSTRACT FROM AUTHOR]

In situ 3-wt.% (Al3Zr/Al2O3 + ZrB2) particle-reinforced 6016Al-matrix composites were produced and squeezed at 650 °C. The effects of squeezing pressure (10–20 MPa) on the solidification microstructure and properties of the composites were investigated. Squeezed solidification of the 6016Al-matrix composites at 650 °C led to grain sizes of 65–70 µm. The synthesized (Al3Zr/Al2O3 + ZrB2) particles were segregated along the grain boundaries. Fine Mg-Si-rich Guinier–Preston zones or precipitates (~ 5 nm) were formed during solidification. Amorphous Al2O3 was observed adjacent to crystalline Al2O3 particles. The composites exhibited a lower yield strength (YS) of ~ 50 MPa because of the clustered porosity and agglomeration of reinforcement particles in hot spots (50–100 µm), formed during solidification. The composite squeezed under 20 MPa exhibited a superior ultimate tensile strength (UTS) of 186 MPa as compared to 170 MPa of the composite squeezed under 10 MPa. Mechanical properties of both the composites were improved upon hot rolling. Upon 80% thickness reduction by hot rolling, the composite squeezed under 10 MPa exhibited increase of ~ 300% in YS, ~ 30% in UTS, and 100% in fracture strain, while the composite squeezed under 20 MPa exhibited increase of ~ 260% in YS, ~ 6% in UTS, and ~ 32% in fracture strain. The improvements in properties originated from improved strengthening efficiency of (Al3Zr/Al2O3 + ZrB2) particles and homogenization of the microstructure. [ABSTRACT FROM AUTHOR]

Cold rolling the CC AA 5754 aluminum alloy to different reductions was followed by an hour of annealing at 537 °C under varied pressures. The changes in microstructure and texture were studied. According to the findings, high-pressure heat treatment restricts recrystallization, and the restriction effect is stronger as pressure rises. The refining impact of high-pressure heat treatment can refine recrystallized grains, and it becomes stronger as the rolling reduction gets higher. The variation of recrystallization texture is significantly affected by high-pressure heat treatment. The sheet with a 19.6% reduction is found to have a weak cube texture at atmospheric pressure and 2 GPa, but the sheet that has been annealed at 4 GPa and 6 GPa has a strong cube texture and a weak β fiber rolling texture. High-pressure heat treatment improves the intensities of the cube and R textures in the fully recrystallized sheets with the same reduction. The strengthening impact of R texture from high-pressure heat treatment improves with increasing rolling reduction. [ABSTRACT FROM AUTHOR]

Al-xCu alloys (x = 5 wt.%, 15 wt.%, 33 wt.%, and 40 wt.%) were solidified at atmospheric pressure (AP) and at high pressure of 3 GPa (3 GPa). The microstructural evolution was studied, and it shows that the amount of eutectic Al2Cu phase is suppressed in the Al-xCu samples solidified under high pressure compared to the samples solidified under ambient conditions. In addition, the secondary dendritic arm spacing in the Al-15Cu and Al-33Cu alloy decreases when solidified under high pressure. The strain rate sensitivity (m) and activation volume (V*) were calculated from the nanoindentation experiments, and the results show that m increases while V* decreases for the hypoeutectic Al-5Cu and Al-15Cu alloys solidified at 3 GPa. Both m and V* decrease for the eutectic alloy (Al-33Cu), and for the hypereutectic composition (Al-40Cu), m decreases, whereas V* increases when solidified under high pressure. The results suggest that both the strength and plasticity for the hypoeutectic compositions increase simultaneously, while the plasticity decrease in the eutectic composition solidified under high pressure. On the other hand, for the hypereutectic Al-40Cu alloy solidified under 3 GPa, both the strength and plasticity decrease. [ABSTRACT FROM AUTHOR]

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Despite many studies on the influence of cropping practices on soil microbial community structure, little is known about ecological patterns of rare and abundant microbial communities in response to different tobacco cropping systems. Here, using the high-throughput sequencing technique, we investigated the impacts of two different cropping systems on soil biochemical properties and the microbial community composition of abundant and rare taxa and its driving factors in continuous and rotational tobacco cropping systems in the mountain lands of Yunnan, China. Our results showed that distinct co-occurrence patterns and driving forces for abundant and rare taxa across the different cropping systems. The abundant taxa were mainly constrained by stochastic processes in both cropping systems. In contrast, rare taxa in continuous cropping fields were mainly influenced by environmental perturbation (cropping practice), while governed by deterministic processes under rotational cropping. The α-diversity indices of rare taxa tended to be higher than those of the abundant ones in the two cropping systems. Furthermore, the network topologies of rare taxa were more complex than those of the abundant taxa in the two cropping systems. These results highlight that rare taxa rather than abundant ones play important roles in maintaining ecosystem diversity and sustaining the stability of ecosystem functions, especially in continuous cropping systems. [ABSTRACT FROM AUTHOR]

With the rapid increase in the functionality of IoT applications, the services provided by edge/IoT devices have surged in the recent past. Fog computing is gaining momentum as a contemporary computational framework for IoT-enabled smart applications that offers a latency sensitivity advantage over cloud computing. Effective task scheduling reduces application computation and latency durations while improves QoS. Many researchers have proposed a variety of heuristic and metaheuristic approaches for effective scheduling; however, there is still scope for improvement. The present work proposes a hybrid of heuristic and metaheuristic techniques for the scheduling of tasks. fireworks algorithm (FWA) is a metaheuristic algorithm, and Heterogeneous Earliest Finish Time (HEFT) is a heuristic algorithm. The bi-objective optimization approach is presented to minimize the makespan and cost factors. To compare the performance of the algorithm, the experiments have been conducted on distinct and independent scientific workflows. The results of exhaustive simulations have established the significance of the presented BH-FWA algorithm over other comparative approaches. To validate the relevance of the technique for fog computing networks, the metrics utilized for comparisons are makespan, cost, and throughput. [ABSTRACT FROM AUTHOR]

Human population is exceeding beyond the carrying capacity of earth resources and stresses like water shortage faced by the plants is jeopardizing the food security. Current research study was aimed to investigate the potentials of Zn-Aspartate (Zn-Asp), Zn-Sulphate (ZnSO4) and L-Aspartate (L-Asp) to be used as osmolytes and role of various levels of these chemicals in combating drought stress in maize plants in Punjab, Pakistan. Study was performed on two plots corresponding to drought and controlled environments. The lamina of maize plants was sprinkled row wise with various treatments including No spray (NS), water sprinkle (WS), sprinkle with ZnSO4 0.25% and 0.50%, sprinkle with Zn-Asp 0.25% and 0.50% and Foliar sprinkle of L-Asp 0.5% and 1%, respectively. Role of major osmoprotectants and secondary metabolites was analyzed and positive changes were found in total soluble sugars (41.16), flavonoids (5387.74), tocopherol content (9089.18), ascorbic acid (645.27) and anthocyanin (14.84) conc. which assists in mitigating drought menace on maize. Shoot mineral ions (Ca, K, Zn, P, Mg and N) status of water stressed maize plants was also analyzed and it was found that application experimental dose enhanced their availability to crop. Physio-biochemical studies were performed on antioxidants enzymes like superoxide dismutase (SOD), peroxidase (POD), carotenoid content (CC), malondialdehyde, hydrogen peroxide, aspartate and free amino acid contents. The activity of SOD was increased by 28.5% and activity of POD was increased by 33.33% due to foliar applied 0.5% Zn-Asp under drought stress. Photosynthetic pigments (chlorophyll A, B and total chlorophyll content) analysis was also carried out in this study. It was found that conc. of different chlorophylls pigments increased (chl-A: 2.24, chl-B: 25.12, total chl: 24.30) which enhanced photosynthetic activity culminating into better growth and yield). The level of malondialdehyde and hydrogen peroxide decreased by 43.9% and 32.8% respectively on treatment with 0.5% Zn-Asp proving the efficacy of the treatment in drought amelioration. Study reveals that Zn-Asp induced modulations are far better than conventional sulphate salts in mitigating water scarce environment. Current study recommends the use of the Zn-Asp to meet the global food and agricultural challenges as compared to ZnSO4 and L-Asp due to its better drought amelioration properties. This research provides valuable informations which can used for future research and practical use in agriculture fields by indigenous and other people to enhance yield of maize to meet the food necessities of country. [ABSTRACT FROM AUTHOR]

The history of plants to be utilized as medicines is thousands of years old. Black cumin is one of the most widely examined plant possessing naturally occurring compounds with antimicrobial potential. Foliar application of growth stimulators is a successful strategy to enhance yield and quality in many crops. A field study was planned to apply growth stimulator like moringa leaf extract on black cumin crop grown under field conditions using RCB design with three replications. All other agronomic inputs and practices were uniform. The treatments were moringa leaf extract concentrations (10%, 20%), growth stages (40 days after sowing, 80 DAS, 120 DAS, 40 + 80 DAS, 40 + 120 DAS, 80 + 120 DAS, 40 + 80 + 120 days after sowing) and two controls unsprayed check (i.e. no moringa leaf extract, no water) and sprayed check (no moringa leaf extract + water). Application of 20% moringa leaf extract at stage-7 (40 + 80 + 120 days after sowing) had significantly increased plant height, branches plant−1, essential oil content, fixed oil content, peroxidase value and iodine value of black cumin oil over unsprayed control. Application of moringa leaf extract showed maximum results and improves growth and yield of black cumin when applied at 40 + 80 + 120 days after sowing. As this study was only conducted using moringa leaf extract, it is advisable to conduct an experiment with various bio stimulants along with fertilizer combinations and growth regulators to check their synergistic effects for more reliable and acceptable recommendations in future. [ABSTRACT FROM AUTHOR]

Summary: Drought stress seriously limits crop productivity. Although studies have been carried out, it is still largely unknown how plants respond to drought stress. Here we find that drought treatment can enhance the phosphorylation activity of brassinosteroid‐signaling kinase 1 (ZmBSK1) in maize (Zea mays).Our genetic studies reveal that ZmBSK1 positively affects drought tolerance in maize plants. ZmBSK1 localizes in plasma membrane, interacts with calcium/calmodulin (Ca2+/CaM)‐dependent protein kinase (ZmCCaMK), and phosphorylates ZmCCaMK. Ser‐67 is a crucial phosphorylation site of ZmCCaMK by ZmBSK1.Drought stress enhances not only the interaction between ZmBSK1 and ZmCCaMK but also the phosphorylation of Ser‐67 in ZmCCaMK by ZmBSK1. Furthermore, Ser‐67 phosphorylation in ZmCCaMK regulates its Ca2+/CaM binding, autophosphorylation and transphosphorylation activity, and positively affects its function in drought tolerance in maize.Our results reveal an important role for ZmBSK1 in drought tolerance and suggest a direct regulatory mode of ZmBSK1 phosphorylating ZmCCaMK. [ABSTRACT FROM AUTHOR]

We analyze the specific features of the structure and elastic characteristics of powder titanium-matrix composites reinforced with titanium carbide and titanium boride. The difference between the characters of dependence of the modulus of elasticity on the content of high-modulus component is analyzed for sintered and hot-forged composites. It is discovered that the modulus of sintered materials is determined both by the content of reinforcing admixtures and by the porosity of the alloy. At the same time, for hot-forged specimens, the modulus monotonically increases with the content of the high-modulus components. It is shown that, for sintered composites of all compositions and for hot-forged composites reinforced by titanium carbide, anisotropy is practically absent, whereas for hot-forged composites reinforced by titanium boride, an insignificant (up to 10%) anisotropy of the structure and elastic characteristics is caused by the reorientation of acicular titanium monoboride particles in the direction perpendicular to the direction of application of the active force in course of hot forging. [ABSTRACT FROM AUTHOR]

We study the structure, crystallization, and performances of the sealing glasses with the composition (mol.%) of 12Al2O3·8B2O3·40SiO2·40RO (R = Mg, Ca, Sr) for solid oxide fuel cells (SOFCs) before and after isothermal treatment at 700°C, which is within the operation temperature range (600‐800°C) of SOFCs. The crystallization behavior has been investigated by differential scanning calorimetry and X‐ray diffraction under both dynamic and isothermal conditions. The structural evolution is probed using the Raman and nuclear magnetic resonance spectroscopies. The performances of the sealing glasses are characterized in terms of the coefficient of thermal expansion, the crystallization‐induced stress at glass–steel interface. We find that strong crystallization occurs at the operation temperature (700°C) far below the crystallization onset temperature measured by DSC. The structure origin of this anomalous crystallization is discussed in terms of structural heterogeneity of the three studied glasses. We determine the residual stress at the interface between the Ca‐containing glass and the steel after isothermal treatment at 700°C for 48 h, but this stress does not lead to falling off the glass layer from the steel. This indicates that this glass is a good candidate to be applied in SOFCs. [ABSTRACT FROM AUTHOR]

Brassinosteroids (BR) play diverse roles in the regulation of plant growth and development. BR promotes plant growth by triggering cell division and expansion. However, the effect of exogenous BR application on the leaf size and expansion of tobacco is unknown. Tobacco seedlings are treated with different concentrations of exogenous 2,4-epibrassinolide (EBL) [control (CK, 0 mol L−1), T1 (0.5 × 10−7 mol L−1), and T2 (0.5 × 10−4 mol L−1)]. The results show that T1 has 17.29% and T2 has 25.99% more leaf area than control. The epidermal cell area is increased by 24.40% and 17.13% while the number of epidermal cells is 7.06% and 21.06% higher in T1 and T2, respectively, relative to control. So the exogenous EBL application improves the leaf area by increasing cell numbers and cell area. The endogenous BR (7.5 times and 68.4 times), auxin (IAA) (4.03% and 25.29%), and gibberellin (GA3) contents (84.42% and 91.76%) are higher in T1 and T2, respectively, in comparison with control. Additionally, NtBRI1, NtBIN2, and NtBES1 are upregulated showing that the brassinosteroid signaling pathway is activated. Furthermore, the expression of the key biosynthesis-related genes of BR (NtDWF4), IAA (NtYUCCA6), and GA3 (NtGA3ox-2) are all upregulated under EBL application. Finally, the exogenous EBL application also upregulated the expression of cell growth-related genes (NtCYCD3;1, NtARGOS, NtGRF5, NtGRF8, and NtXTH). The results reveal that the EBL application increases the leaf size and expansion by promoting the cell expansion and division through higher BR, IAA, and GA3 contents along with the upregulation of cell growth-related genes. The results of the study provide a scientific basis for the effect of EBL on tobacco leaf growth at morphological, anatomical, biochemical, and molecular levels. [ABSTRACT FROM AUTHOR]

Background: Weather change in high-altitude areas subjects mature tobacco (Nicotiana tabacum L.) to cold stress, which damages tobacco leaf yield and quality. A brupt diurnal temperature differences (the daily temperature dropping more than 20 °C) along with rainfall in tobacco-growing areas at an altitude above 2450 m, caused cold stress to field-grown tobacco. Results: After the flue-cured tobacco suffered cold stress in the field, the surface color of tobacco leaves changed and obvious large browning areas were appeared, and the curing availability was extremely poor. Further research found the quality of fresh tobacco leaves, the content of key chemical components, and the production quality were greatly reduced by cold stress. We hypothesize that cold stress in high altitude environments destroyed the antioxidant enzyme system of mature flue-cured tobacco. Therefore, the quality of fresh tobacco leaves, the content of key chemical components, and the production quality were greatly reduced by cold stress. Conclusion: This study confirmed that cold stress in high-altitude tobacco areas was the main reason for the browning of tobacco leaves during the tobacco curing process. This adverse environment seriously damaged the quality of tobacco leaves, but can be mitigated by pay attention to the weather forecast and pick tobacco leaves in advance. [ABSTRACT FROM AUTHOR]

Cereals are important crops worldwide that help meet food demands and nutritional needs. In recent years, cereal production has been challenged globally by frequent droughts and hot spells. A plant's root is the most relevant organ for the plant adaptation to stress conditions, playing pivotal roles in anchorage and the acquisition of soil-based resources. Thus, dissecting root system variations and trait selection for enhancing yield and sustainability under drought stress conditions should aid in future global food security. This review highlights the variations in root system attributes and their interplay with shoot architecture features to face water scarcity and maintain thus yield of major cereal crops. Further, we compile the root-related drought responsive quantitative trait loci/genes in cereal crops including their interspecies relationships using microsynteny to facilitate comparative genomic analyses. We then discuss the potential of an integrated strategy combining genomics and phenomics at genetic and epigenetic levels to explore natural genetic diversity as a basis for knowledge-based genome editing. Finally, we present an outline to establish innovative breeding leads for the rapid and optimized selection of root traits necessary to develop resilient crop varieties. [ABSTRACT FROM AUTHOR]

Summary: In their natural environment, plants are exposed to biotic or abiotic stresses that occur sequentially or simultaneously. Plant responses to these stresses have been studied widely and have been well characterised in simplified systems involving single plant species facing individual stress. Temperature elevation is a major abiotic driver of climate change and scenarios have predicted an increase in the number and severity of epidemics. In this context, here we review the available data on the effect of heat stress on plant–pathogen interactions. Considering 45 studies performed on model or crop species, we discuss the possible implications of the optimum growth temperature of plant hosts and pathogens, mode of stress application and temperature variation on resistance modulations. Alarmingly, most identified resistances are altered under temperature elevation, regardless of the plant and pathogen species. Therefore, we have listed current knowledge on heat‐dependent plant immune mechanisms and pathogen thermosensory processes, mainly studied in animals and human pathogens, that could help to understand the outcome of plant–pathogen interactions under elevated temperatures. Based on a general overview of the mechanisms involved in plant responses to pathogens, and integrating multiple interactions with the biotic environment, we provide recommendations to optimise plant disease resistance under heat stress and to identify thermotolerant resistance mechanisms. [ABSTRACT FROM AUTHOR]

A Co25.1Cr18.8Fe23.3Ni22.6Ta8.5Al1.7 (at. %) eutectic high-entropy alloy (EHEA) consisting of face-centered-cubic (FCC) and C14 Laves phases was produced by powder metallurgy. The EHEA shows an equiaxed morphology that is different from eutectic lamellar structure. Nanometer L12 phase (4–5 nm) further precipitates in FCC matrix. The microstructure is highly stable upon annealing at 1000°C for 100 h, which leads to attractive high-temperature strength. The fracture behaviour is observed to be modified by the equiaxed Laves phase, which contains microcracks induced by multiple dislocation slips. The diversified cracking modes help to relieve stress concentration and therefore enhance ductility at high temperatures. High-temperature tensile properties of a eutectic high-entropy alloy (EHEAs) are significantly improved compared to those of casted EHEAs, through modification of lamellar structure to an equiaxed one by powder metallurgy. [ABSTRACT FROM AUTHOR]

In this study, the effect of CaZrO3 additives on the phase and microstructure of BaZrO3 refractory were investigated as well as the interaction with titanium alloy melts. Results revealed that no second phase was observed in the BaZrO3 refractory with 10 and 20 mol% CaZrO3 additives, respectively, and the incorporation CaZrO3 additives promoted the densification and the growth of grains due to the generation of BaZrO3‐CaZrO3 solid solutions. Whereas, the appearance of CaZrO3 phase was in the BaZrO3 refractory with 30 mol% additive, indicating that the additive content excessed the solid solubility limit in the BaZrO3 refractory. Interaction analysis indicated that CaZrO3 additive could improve the performance of BaZrO3 refractory for resisting the penetration of Ti2Ni alloy melt. Meanwhile, an increasing extent of melt contamination by the BaZrO3 refractory was also detected with the increasing content of CaZrO3 additive. According to the thermodynamic calculation, an obvious increase in Gibbs free energy of formation for the BaZrO3 refractory was confirmed with the CaZrO3 additive, resulting in the increasing extent of the dissolution‐corrosion between the refractory and the titanium alloy melts. [ABSTRACT FROM AUTHOR]

The RP-HPLC based comparative quantification of some important redox sensitive phenolic acids and flavonoids revealed overall greater elicitation of chalcone synthase related flavonoid biosynthetic pathway, concomitant with the greater utilization of cinnamic acid for the seedlings of the salinity resistant rice cultivar Patnai as compared to susceptible cultivar IR29 grown under post imbibitional salinity stress (PISS). When compared, the cultivar Patnai further exhibited significantly better antioxidant-coupled redox-regulation by up regulating ascorbate–glutathione pathway and reducing the expression of oxidative deterioration under PISS as compared to its counterpart, the cultivar IR29. A model for redox homeostasis in which complementation of action of ROS scavenging secondary metabolites with enzymatic antioxidant defense at metabolic interface necessary for maintenance of the redox homeostasis to combat salinity stress has been proposed. [ABSTRACT FROM AUTHOR]

Background: Frequently occurring drought stress negatively affects the production of maize worldwide. Numerous efforts have been made to develop drought-tolerant maize lines and to explore drought tolerant mechanisms in maize. However, there is a lack of comparative studies on transcriptomic changes between drought-tolerant and control maize lines. Results: In the present study, we have developed a drought-tolerant maize mutant (C7–2t) by irradiating the seeds of maize inbred line ChangC7–2 (C7–2) with 60Co-γ. Compared to its wild type C7–2, C7–2t exhibited a significantly delayed wilting and higher drought tolerance under both the controlled and field conditions, indicating its high water-holding ability. Transcriptomic profiling was performed to identify differentially expressed genes (DEGs) between C7–2 and C7–2t during drought. As a result, a total of 4552 DEGs were implied in drought tolerance of C7-2 and C7-2t. In particular, the expression of photosynthesis-related genes in C7–2 was inhibited, whereas these genes in C7–2t were almost unaffected under drought. Moreover, a specific set of the DEGs were involved in phenylpropanoid biosynthesis and taurine (hypotaurine) metabolism in C7–2t; these DEGs were enriched in cell components associated with membrane systems and cell wall biosynthesis. Conclusions: The drought tolerance of C7–2t was largely due to its high water-holding ability, stable photosynthesis (for supporting osmoregulation) and strengthened biosynthesis of cell walls under drought conditions. [ABSTRACT FROM AUTHOR]

Susceptibility of plants to abiotic stresses, including extreme temperatures, salinity and drought, poses an increasing threat to crop productivity worldwide. Here the drought-induced response of maize was modulated by applications of methyl jasmonate (MeJA) and salicylic acid (SA) to seeds prior to sowing and to leaves prior to stress treatment. Pot experiments were conducted to ascertain the effects of exogenous applications of these hormones on maize growth, physiology and biochemistry under drought stress and well-watered (control) conditions. Maize plants were subjected to single as well as combined pre-treatments of MeJA and SA. Drought stress severely affected maize morphology and reduced relative water content, above and below-ground biomass, rates of photosynthesis, and protein content. The prolonged water deficit also led to increased relative membrane permeability and oxidative stress induced by the production of malondialdehyde (from lipid peroxidation), lipoxygenase activity (LOX) and the production of H2O2. The single applications of MeJA and SA were not found to be effective in maize for drought tolerance while the combined pre-treatments with exogenous MeJA+SA mitigated the adverse effects of drought-induced oxidative stress, as reflected in lower levels of lipid peroxidation, LOX activity and H2O2. The same pre-treatment also maintained adequate water status of the plants under drought stress by increasing osmolytes including proline, total carbohydrate content and total soluble sugars. Furthermore, exogenous applications of MeJA+SA approximately doubled the activities of the antioxidant enzymes catalase, peroxidase and superoxide dismutase. Pre-treatment with MeJA alone gave the highest increase in drought-induced production of endogenous abscisic acid (ABA). Pre-treatment with MeJA+SA partially prevented drought-induced oxidative stress by modulating levels of osmolytes and endogenous ABA, as well as the activities of antioxidant enzymes. Taken together, the results show that seed and foliar pre-treatments with exogenous MeJA and/or SA can have positive effects on the responses of maize seedlings to drought. [ABSTRACT FROM AUTHOR]

Background: Brassinolide (BR), as a new type of plant hormones, is involved in the processes of plant growth and stress response. Previous studies have reported the roles of BR in regulating plant developmental processes and also response tolerance to abiotic stresses in plants. The main purpose of our study was to explore whether nitric oxide (NO) plays a role in the process of BR-induced adventitious root formation in cucumber (Cucumis sativus L.). Results: Exogenous application of 1 μM BR significantly promoted adventitious rooting, while high concentrations of BR (2–8 μM) effectively inhibited adventitious rooting. NO donor (S-nitroso-N-acerylpenicillamine, SNAP) promoted the occurrence of adventitious roots. Simultaneously, BR and SNAP applied together significantly promoted adventitious rooting and the combined effect was superior to the application of BR or SNAP alone. Moreover, NO scavenger (c-PTIO) and inhibitors (L-NAME and Tungstate) inhibited the positive effects of BR on adventitious rooting. BR at 1 μM also increased endogenous NO content, NO synthase (NOS-like) and Nitrate reductase (NR) activities, while BRz (a specific BR biosynthesis inhibitor) decreased these effects. In addition, the relative expression level of NR was up-regulated by BR and SNAP, whereas BRz down-regulated it. The application of NO inhibitor (Tungstate) in BR also inhibited the up-regulation of NR. Conclusion: BR promoted the formation of adventitious roots by inducing the production of endogenous NO in cucumber. [ABSTRACT FROM AUTHOR]

Background: The leaf age for harvesting flue-cured tobacco leaves is closely related to the quality of tobacco leaves, so an appropriate leaf age for harvesting is important for improving yield and quality of flue-cured tobacco, however, at present, there are few studies on effects of leaf age on physiological and biochemical changes during flue-curing and there is no clear standard of proper leaf ages for harvesting in production. Results: In the Yunnan tobacco-growing area, an experiment was carried from 2016 to 2017 and different leaf ages were set. The results demonstrate that leaf age has a significant on tissue cell gap, leaf age and flue-curing stages exert significant effects on upper epidermis, palisade and spongy tissue, and leaf thickness of tobacco leaves. The thicknesses of upper and lower epidermis as well as palisade and spongy tissues at different ages show an approximately W-shaped change trend during flue-curing. With the advance of flue-curing stages, contents of starch, chlorophyll, carotenoid, and water in tobacco leaves at different leaf ages decrease, while polyphenol and malondialdehyde (MDA) contents increase. The older the leaf, the faster the chlorophyll, carotenoid, and water contents reduce, while the faster the polyphenol and MDA content rise during flue-curing. The flue-cured tobacco leaves at 116 DAT (days after transplanting) show the highest contents of total nitrogen and nicotine, followed by 123 DAT and those at 130 DAT are the lowest; however, the contents of total sugar and reducing sugar demonstrate a contrary tendency, and the starch content at 116 DAT is much lower than those in the other two treatments. The proportion of superior tobacco, average price, yield, and output value of upper tobacco leaves at different leaf ages are the highest at 123 DAT. The highest sensory evaluation score is found at 123 DAT, while that at 130 DAT is significantly lower in comparison with the other two treatments. Conclusions: Tobacco leaves harvested at 123 DAT are mature and exhibit a low degree of membrane lipid peroxidation, moderate chemical compositions, and high economic value. 123 DAT improves availability of tobacco leaves. [ABSTRACT FROM AUTHOR]

Drought has is becoming increasingly serious abiotic stress that influences plant growth. Endophytes are non-pathogenic plant-associated bacteria that can play an important role in conferring plant resistance to drought stress. In this study, drought stress resulted in the evident breakdown of the chloroplast membrane system in leaf cells, whereas Bacillus pumilus inoculation improved the integrity of chloroplast and mitochondria cell structure. Thus chlorophyll content, photosynthetic parameters and water use efficiency increased. The inoculation of endophytes alleviated the inhibitory effect of drought stress on Glycyrrhiza uralensis growth. We concluded that B. pumilus inoculation enhanced the growth and drought tolerance of G. uralensis through the protection of chloroplast submicroscopic structure, and thus increased chlorophyll content, efficient photosynthetic rate, and improved water state. [ABSTRACT FROM AUTHOR]

Al–50Si alloys for electronic packaging were prepared by gas atomization following hot press sintering, and the influences of adding minor Sc (0.3%) on microstructure and mechanical and thermo-physical properties were studied. The Si phase exhibits a semi-continuous network structure with an average size of 15–20 μm in the alloys with and without Sc addition. Transmission electron microscopy observation indicates that a fine spherical Sc-rich particle distributes at the interface between the Al matrix and Si phase in the Al–50Si-Sc alloy, which is further identified as AlSi2Sc2 (V-phase). The tensile strength, flexural strength, and hardness of the Al–50Si alloy are improved by 16.2%, 8.9%, and 14.7%, respectively, with the introduction of Sc. However, the coefficient of thermal expansion and thermal conductivity decreases slightly in the Al–50Si–Sc alloy as compared with the Al–50Si alloy. The increased strength is mainly attributed to the formation of fine spherical AlSi2Sc2 phase which strengthens the Al matrix. [ABSTRACT FROM AUTHOR]

Despite being an important crop option for Brazilian agriculture, canola has some characteristics that may limit its insertion in some cropping systems, such as its allelopathic effects. Thus, the present work aimed to study the effect of canola crop residues on the seed germination, growth and grain yield of white oat and wheat plants. In laboratory conditions, white oat (Milton) and wheat (Tbio Pioneiro) seeds were germinated in the presence of aqueous extracts of (i) aboveground part, (ii) root system, (iii) whole plant and (iv) twice the concentration of the whole plant extract, besides a control. In green house conditions, the same oat and wheat cultivars were grown until harvest, on soil mixed with fresh canola crop residues (whole plant residues, aboveground residues and root residues) and a control. Aqueous extract of the whole canola plant reduced the germination and increased abnormal seedlings of white oat and wheat, mainly in high concentration. For soil crop, the presence of canola residues did not affect the white oat emergence, growth and grain yield. For wheat, plant emergence was lower in the presence of canola residues, but growth and yield were not affected. [ABSTRACT FROM AUTHOR]

Abstract: Although numerous investigations have studied BaZrO3 as a crucible refractory for melting titanium alloys, the interaction mechanism between them has not been clarified. In this study, a set of three designed alloys with different Ti composition (TiNi, Ti1.5Ni, and Ti2Ni) were melted in the BaZrO3 crucibles. By using the X‐ray diffraction, optical, and scanning electron microscopy analysis, the interactions between the BaZrO3 crucibles and the titanium melts were investigated. It was found that dissolution of the BaZrO3 refractory into the titanium melts resulted in the crucible erosion and the melt contamination, the degree of which were both increased with the increasing of Ti content in the melts. The dissolution reaction could be determined as follows: TixNi ( l ) + x 2 BaZrO 3 ( s ) → TixNi x 2 Zr, xO ( l ) + x 2 BaO ( l ). The oxygen content dissolved in TiNi, Ti1.5Ni, and Ti2Ni melts was thermodynamically calculated as 0.0055, 0.1922, and 0.2263 wt%, respectively, which were in agreement with the experimental results. [ABSTRACT FROM AUTHOR]

An MgZnY fine-grained solidified alloy with a grain size of 16 μm was prepared by high-pressure solidification. The microstructure characteristics and hot compressive deformation behavior of the alloy solidified under high pressure were compared with the atmospheric-pressure solidified alloy by carrying out the unilateral compression tests under a strain rate in the range of 0.001-1.0 s and at a deformation temperature in the range of 523-573 K. The true stress-true strain curve of the high-pressure solidified alloy shows the typical dynamic recrystallization rheological curve. EBSD results show that when the deformation was carried out at 573 K, nearly 90% dynamic recrystallization occurred in the high-pressure solidified alloy, and the newly formed grains were distortionless and had low dislocation density. The high-pressure solidified alloy showed a double-peak basal texture at a strain rate of 1.0 s. The two peak points showed a maximum pole density of 9.88 and 7.91, less than that in atmospheric-pressure alloy. When the deformation was carried out at the following conditions: deformation temperature = 573 K, strain rate = 0.001, and true strain = 0.9, the average Schmid factor (SF) for basal slip of the grains in the high-pressure solidified alloy was 0.419, and SF value for basal slip in 91% grains was greater than 0.3. [ABSTRACT FROM AUTHOR]

Cardiovascular disorders are the leading cause of mortality worldwide. Berberis vulgaris (B. vulgaris) is a commonly used plant in traditional medicine. In recent studies, B. vulgaris showed antiarrhythmic, antihypertensive, anticholinergic, and cardioprotective effects. We reviewed the literature to explore the possible prophylactic and therapeutic roles of B. vulgaris in cardiovascular medicine. A computer literature search was conducted to identify all relevant studies that have investigated the role of B. vulgaris in prevention or treatment of cardiovascular diseases. We also searched the citations of the retrieved articles. Using a systematic approach, we conducted a scoping review that included a total of 37 articles. Twelve studies examined the antihypertensive effects of B. vulgaris, seven studies investigated its antiarrhythmic effects, while its inotropic and cardioprotective effects were evaluated in four and eight studies, respectively. B. vulgaris showed a beneficial effect in reducing blood pressure, enhancing cardiac contractility, and protection from reperfusion injury. However, the mechanisms of these effects are still under investigation. Moreover, it could modify major risk factors for cardiovascular disorders, such as oxidative stress, hyperglycemia, and hyperlipidemia. Further studies are needed to translate these findings into effective cardiovascular medications. [ABSTRACT FROM AUTHOR]

Water deficit is considered the main abiotic stress that limits agricultural production worldwide. Brassinosteroids (BRs) are natural substances that play roles in plant tolerance against abiotic stresses, including water deficit. This research aims to determine whether BRs can mitigate the negative effects caused by water deficiency, revealing how BRs act and their possible contribution to increased tolerance of cowpea plants to water deficit. The experiment was a factorial design with the factors completely randomised, with two water conditions (control and water deficit) and three levels of brassinosteroids (0, 50 and 100 nM 24-epibrassinolide; EBR is an active BRs). Plants sprayed with 100 nM EBR under the water deficit presented significant increases in Φ, q and ETR compared with plants subjected to the water deficit without EBR. With respect to gas exchange, P , E and g exhibited significant reductions after water deficit, but application of 100 nM EBR caused increases in these variables of 96, 24 and 33%, respectively, compared to the water deficit + 0 nM EBR treatment. To antioxidant enzymes, EBR resulted in increases in SOD, CAT, APX and POX, indicating that EBR acts on the antioxidant system, reducing cell damage. The water deficit caused significant reductions in Chl a, Chl b and total Chl, while plants sprayed with 100 nM EBR showed significant increases of 26, 58 and 33% in Chl a, Chl b and total Chl, respectively. This study revealed that EBR improves photosystem II efficiency, inducing increases in Φ, q and ETR. This substance also mitigated the negative effects on gas exchange and growth induced by the water deficit. Increases in SOD, CAT, APX and POX of plants treated with EBR indicate that this steroid clearly increased the tolerance to the water deficit, reducing reactive oxygen species, cell damage, and maintaining the photosynthetic pigments. Additionally, 100 nM EBR resulted in a better dose-response of cowpea plants exposed to the water deficit. [ABSTRACT FROM AUTHOR]

The solidification microstructures of AE42 (Mg-4Al-2RE, wt%) alloys with three different cooling rates are investigated using CALculation of PHase Diagrams (CALPHAD) simulation and experimental validation. The results show that high cooling rates can refine the microstructure and decrease the formation of particulate AlRE intermetallics. Particularly, the MgAl phase, predicted by CALPHAD simulation using the Scheil model, is not observed in the high-pressure die casting (HPDC) sample. The suppression of MgAl in HPDC AE42 alloy at high cooling rates and high pressure is likely due to the supersaturation of Al in (Mg), in addition to the preferential formation of AlRE and AlRE phases. [ABSTRACT FROM AUTHOR]

In this investigation, pot culture experiment was carried out to estimate the ameliorating effect of triazole compounds, namely Triadimefon (TDM), Tebuconazole (TBZ), and Propiconazole (PCZ) on drought stress, photosynthetic pigments, and biochemical constituents of Zea mays L. (Maize). From 30 days after sowing (DAS), the plants were subjected to 4 days interval drought (DID) stress and drought with TDM at 15 mg l, TBZ at 10 mg l, and PCZ at 15 mg l. Irrigation at 1-day interval was kept as control. Irrigation performed on alternative day. The plant samples were collected on 40, 50, and 60 DAS and separated into root, stem, and leaf for estimating the photosynthetic pigments and biochemical constituents. Drought and drought with triazole compounds treatment increased the biochemical glycine betaine content, whereas the protein and the pigments contents chlorophyll-a, chlorophyll-b, total chlorophyll, carotenoid, and anthocyanin decreased when compared to control. The triazole treatment mitigated the adverse effects of drought stress by increasing the biochemical potentials and paved the way to overcome drought stress in corn plant. [ABSTRACT FROM AUTHOR]

In order to evaluate the fresh weight, RWC, pigment content, total phenolics, proline and glycine betaine responses of maize inbred lines to osmotic stress, a factorial experiment was carried out under laboratory conditions with two maize inbred lines (B73 and MO17) and two osmotic stress levels induced by PEG (control and -0.6 MPa). Fresh weight significantly decreased under drought stress. On the basis of percent inhibition in fresh weight at the osmotic stress MO17 was ranked as tolerant (inhibition 45.30%), and B73 drought sensitive (inhibition more than 50%). Leaf relative water content (RWC) was significantly decreased in both inbred lines under osmotic stress. The pigment concentrations were substantially declined in both maize inbreds under osmotic stressed conditions. However, this reduction was less in B73 than MO17. Osmoitc stress declined the levels of total phenolics in both maize inbreds. On the other hand, the osmotic stress markedly enhanced the levels of proline and glycine betaine in both maize inbreds, but this was more pronounced in MO17. The present results showed that osmotic stress retards the growth and some biochemical attributes of maize inbreds. In conclusion, the level of proline and glycine betaine in maize could improve drought tolerance. [ABSTRACT FROM AUTHOR]

To understand the molecular responses of PC (Overexpressing the maize C4- pepc gene, which encodes phosphoenolpyruvate carboxylase (PEPC)), to drought stress at cell level, we analyzed changes in the levels of signaling molecules (hydrogen peroxide (H2O2), calcium ion (Ca2+), and nitric oxide (NO)) in suspension-cultured PC and wild-type (WT) rice ( Oryza sativa L.) cell under drought stress induced by 20% polyethylene glycol 6000 (PEG-6000). Results demonstrated that PC improved drought tolerance by enhancing antioxidant defense, retaining higher relative water content, survival percentages, and dry weight of cells. In addition, PEPC activity in PC under PEG treatment was strengthened by addition of H2O2 inhibitor, dimethylthiourea (DMTU) and NO synthesis inhibitor, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO), respectively, while that in PC was weakened by addition of free calcium chelator, ethylene glycol-bis(b-aminoethylether)- N, N, N′, N′-tetraacetic acid (EGTA) + calcium channel outflow inhibitor, ruthenium red (RR) + plasma membrane channel blocker La(NO3)3, but EGTA + RR did not. Results also showed that NO and Ca2+ was lying downstream of H2O2 in drought-induced signaling. Calcium ion was also involved in the expression of C 4 -pepc in PC. These results suggested that PC could improve oxidative tolerance in suspension-cultured cells and the acquisition of this tolerance required downregulation of H2O2 and the entry of extracellular Ca2+ into cells across the plasma membrane for regulation of PEPC activity and C 4 -pepc expression. [ABSTRACT FROM AUTHOR]

Water and nitrogen are among the most important crop inputs for optimum production of maize (Zea mays L.). A comprehensive experiment was conducted during 2009 and 2010 under the semiarid conditions of Pakistan to evaluate the effects of water and N applications on the growth and yield of irrigated maize. The objective was to formulate water and N best management practices (BMPs) for the above conditions. Three irrigation regimes (525, 450, and 375 mm ha-1) with 5 N rates (0, 75, 150, 225, and 300 kg ha-1) were tested using a split plot with a randomized complete block design. The results revealed that the irrigation and N treatments significantly affected growth and development of the crop plants. Photosynthesis and transpiration rates were influenced by the applied nutrients. The N application at 225 kg ha-1 resulted in maximum values for photosynthesis (26.90 and 27.63 µmol m-2 s-1 during 2009 and 2010, respectively) and transpiration (5.23 and 5.43 m mol m-2 s-1during 2009 and 2010, respectively). The highest values for leaf area index ha-1(4.93) and grain yield (8.40 t ha-1 ) were also recorded at this N treatment during both growing seasons. On the other hand, the mean crop growth rate (19.23 g m-2day-1 ) and biological yield (16.22 t ha-1) were achieved with the 300 kg N ha-1 treatments in 2009 and 2010. Nitrogen use efficiency (NUE) was optimum at 75 kg N ha-1 during both seasons. The highest water use efficiency (WUE) (16.48 and 18.64 kg ha-1 mm-1during 2009 and 2010, respectively) was achieved by application of 225 kg N ha-1 with an irrigation water depth of 525 mm during both growing seasons. Water stress at the vegetative stage reduced the grain yield by 12.2%, whereas the same treatment at the grain filling stage reduced the grain yield by 22.6%. In the semiarid environment of Pakistan, the application of water at 525 mm ha-1with 225 kg N ha-1 gave the optimum production of the irrigated maize tested in this experiment. These crop inputs may be considered as water and N BMPs for this region or for those with similar agricultural and environmental conditions. Agricultural inputs based on these BMPs may result in similar NUE and WUE values. [ABSTRACT FROM AUTHOR]