Soil remediation for cadmium (Cd) toxicity is essential for successful tobacco cultivation and production. Melatonin application can relieve heavy metal stress and promote plant growth; however, it remains somewhat unclear whether melatonin supplementation can remediate the effects of Cd toxicity on the growth and development of tobacco seedlings. Herein, we evaluated the effect of soil-applied melatonin on Cd accumulation in tobacco seedlings, as well as the responses in growth, physiological and biochemical parameters, and the expression of stress-responsive genes. Our results demonstrate that melatonin application mitigated Cd stress in tobacco, and thus promoted plant growth. It increased root fresh weight, dry weight, shoot fresh weight and dry weight by 58.40%, 163.80%, 34.70% and 84.09%, respectively, compared to the control. Physiological analyses also showed significant differences in photosynthetic rate and pigment formation among the treatments, with the highest improvements recorded for melatonin application. In addition, melatonin application alleviated Cd-induced oxidative damage by reducing MDA content and enhancing the activities of enzymatic antioxidants (CAT, SOD, POD and APX) as well as non-enzymatic antioxidants (GSH and AsA). Moreover, confocal microscopic imaging confirmed the effectiveness of melatonin application in sustaining cell integrity under Cd stress. Scanning Electron Microscopy (SEM) observations illustrated the alleviative role of melatonin on stomata and ultrastructural features under Cd toxicity. The qRT-PCR analysis revealed that melatonin application upregulated the expression of photosynthetic and antioxidant-related genes, including SNtChl, q-NtCSD1, NtPsy2 and QntFSD1, in tobacco leaves. Together, our results suggest that soil-applied melatonin can promote tobacco tolerance to Cd stress by modulating morpho-physiological and biochemical changes, as well as the expression of relevant genes.

Plant pathogens pose a high risk of yield losses and threaten food security. Technological and scientific advances have improved our understanding of the molecular processes underlying host-pathogen interactions, which paves the way for new strategies in crop disease management beyond the limits of conventional breeding. Cross-family transfer of immune receptor genes is one such strategy that takes advantage of common plant immune signalling pathways to improve disease resistance in crops. Sensing of microbe- or host damage-associated molecular patterns (MAMPs/DAMPs) by plasma membrane-resident pattern recognition receptors (PRR) activates pattern-triggered immunity (PTI) and restricts the spread of a broad spectrum of pathogens in the host plant. In the model plant Arabidopsis thaliana, the S-domain receptor-like kinase LIPOOLIGOSACCHARIDE-SPECIFIC REDUCED ELICITATION (AtLORE, SD1-29) functions as a PRR, which senses medium-chain-length 3-hydroxylated fatty acids (mc-3-OH-FAs), such as 3-OH-C10:0, and 3-hydroxyalkanoates (HAAs) of microbial origin to activate PTI. In this study, we show that ectopic expression of the Brassicaceae-specific PRR AtLORE in the solanaceous crop species Solanum lycopersicum leads to the gain of 3-OH-C10:0 immune sensing without altering plant development. AtLORE-transgenic tomato shows enhanced resistance against Pseudomonas syringae pv. tomato DC3000 and Alternaria solani NL03003. Applying 3-OH-C10:0 to the soil before infection induces resistance against the oomycete pathogen Phytophthora infestans Pi100 and further enhances resistance to A. solani NL03003. Our study proposes a potential application of AtLORE-transgenic crop plants and mc-3-OH-FAs as resistance-inducing biostimulants in disease management.

Maize is among the most significant crops in the world regarding production and yield, but it is highly sensitive to drought, which reduces the growth, photosynthetic efficiency, grain quality, and yield production of a plant. Quantum yield efficiency of photosystem II is a critical photosynthetic component that is susceptible to drought stress. This study intended to investigate the effects of drought stress on growth and morpho-physiological parameters using three maize hybrids ('P-3011w', 'P-3092' and 'iku20') with contrasting soil moisture contents (100%, 40%) at the pre-flowering stage. The stress treatment (40%) was initiated at stage V7, for a period of 15 days; the experimental units were established in a completely randomized design with split-plot arrangement along with three repetitions in 42 L pots using a substrate of peat moss, black soil and poultry manure (1:2:1). The morphological, growth-related and physiological parameters were assessed, including chlorophyll fluorescence (Fv/Fm), which was measured using a LiCor-6400-40 fluorometer. The results showed that all morphological, growth-related and physiological variables decreased under drought stress during the reproductive stage, with the exception of leaf temperature and intercellular CO2 concentration, which increased by 12% and 54%, respectively. Drought stress significantly reduced the photosynthetic chlorophyll fluorescence (43%), due to damage to photosystem II. The lowest percentage of damage to photosystem II (34%) was observed in the iku20 genotype. In contrast, P-3011w and P-3092 had the highest levels of significantly similar damage (49% and 46%, respectively). The correlation analysis showed a highly positive interaction of chlorophyll fluorescence (Fv/Fm) with net photosynthetic rate and stomatal conductance under drought conditions, and multiple regression analysis revealed that the maximum effect on net photosynthetic rate under drought was due to the damage it caused to photosystem II. Thus, iku20 might have a tendency to be able to withstand drought stress in the dry northeast region of Mexico. Overall, we concluded that the photosystem II was negatively impacted by drought stress thus causing a reduction in all physiological, morphological and growth-related variables.

Hundreds of studies have been written in the last several decades on the advantages of using stone powder as a raw material in the production of fired clay bricks. The durability and long-term behavior of the finished product, however, have received very little attention in the literature. Clay bricks are generally fired at high temperatures in developing countries, which reduces the mechanical performance of the bricks. This is especially evident in extreme environmental settings where weathering leads to significant damage. The evaluation of concrete waste (stone powder) used to make fired clay bricks is the main topic of this study. There are two sections: the first evaluates how adding stone powder to clay bricks improves their physical characteristics such absorption, efflorescence, density, and firing shrinkage. The impact of stone powder on the mechanical characteristics of specimens of burned clay bricks, such as compressive and flexural strengths, is covered in the second section. The percentages of stone powder in the clay bricks are 0 %, 5 %, 10 %, 15 %, and 20%. While the ratio of dry soil to water content remains is 0.3. In this work three fire phases are used untel to the maximum temperature is reached. The first one is 300 degrees C, the second phase is 600 degrees C, and 900 degrees C for the third phase. The water absorption of specimens decreased as the quantity of stone powder increased, and efflorescence also decreased, according to the results for the physical attributes. The density does, however, somewhat rise with the amount of stone powder. Additionally, when the amount of stone powder was increased, the experimental results indicated that firing shrinkage decreased. Mechanically considered, clay brick specimens with 20% more stone powder showed stronger compressive flexural capabilities.

Soil and water pollution are current global environmental and agricultural challenges, adversely affected by ineffective industrial waste treatment before discharging into the environment combined with inefficient long-term inputs of fertilizers. The development of targeted fertilizers delivery vehicles, sufficient soil/water remediation, and contamination detection systems using eco-friendly technologies become critically important. Due to their high specific surface area, biocompatibility, easiness of operation, and high performance, nanomaterials-based controllable soil fertility promoters, adsorbents, sensors, and photocatalysts are promising tools for soil/water pollution prevention, remediation, and monitoring. Altogether, crystallinity, hydrophilic-tunable surface chemistry, and 3D forming ability of nanocellulose (NC), in addition to biodegradability, regeneration ability, and mechanical properties of NC nanocomposite hydrogels (NCHs), lead to advancing promising soil/water nanohydrogels-based targeted fertilizers delivery vehicles, adsorbents, co-adsorbents/co-sensors, and co-adsorbents/co-photocatalysts. In these systems, NCHs introduce 3D rigid porous scaffolds for homogenous dispersing/fixing of functional groups, fertilizers, fluorescence sources, and photocatalysts. Also, they present stimuli-responsive networks for fertilizer regulation in soil, and matrixes with extra active sites enabling contaminates immobilization/degradation. This review outlines an update of the most recent potential utilization of functionalized NCHs-based soil/water adsorbents, photocatalysts, sensors, and slow/targeted fertilizers release vehicles. An in-depth discussion of surface pretreatments-modifications used to improve their performance, fabrication methods, application properties, and working mechanisms was discussed. The potential limitations and future perspectives on using NCHs in fertilizer/water management, soil/water remediation, and detection are highlighted.

The phenomenon of salt fog on pottery surfaces attracted our team to study it and explain the reason for its formation. The crystallization of salts during drying leads to pottery damage. A significant step is to examine the types of salt and identify the chemical composition of the sherds. For this visual assessment, a digital microscope and a scanning electron microscope with energy dispersive X-ray analyses unit (SEM-EDX) were used to detect surface deterioration. In addition, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analyses were carried out to determine the chemical composition of potsherds and salts. The microscopic examination revealed a dense distribution of salts on the potsherd surface. Besides, the SEM photomicrographs showed clear cubic salt crystals of sodium chloride, especially after drying. The SEM-EDX analysis also revealed high chloride salt concentration, in addition to silica and aluminum oxide, which are the primary ingredients in pottery-making. According to XRD analysis, the pottery samples primarily contained diopside, hematite, magnetite, albite and muscovite, which are the primary components in manufacturing. Furthermore, halite appeared in large proportions due to the influence of burial soil. Besides, the quartz, clay minerals, hematite and calcite content of the samples were confirmed by FTIR. The results thus support the fact that sodium chloride significantly influences archaeological pottery.

The role of atmospheric aerosols in earth's radiative balance is crucial. A thorough knowledge about the spectral optical properties of various types of aerosols is necessary to quantify the net radiative forcing produced by aerosol-light interactions. In this study, we exploited an open-source inverse algorithm based on the Python-PyMieScatt survey iteration method, to retrieve the wavelength dependent Mie-equivalent complex refractive indices of ambient aerosols. This method was verified by obtaining the broadband complex refractive indices of monodisperse polystyrene latex spheres and polydisperse common salt aerosols, using laboratory data collected with a supercontinuum broadband cavity enhanced extinction spectrometer operating in the 420-540 nm wavelength range. Field measurements of ambient aerosol were conducted using a similar cavity enhanced extinction spectrometer (IBBCEES) operating in the wavelength range of 400-550 nm, a multi-wavelength aethalometer, and a scanning mobility particle sizer, in Changzhou city, People's Republic of China. The absorption coefficients for the entire wavelength range were retrieved using the absorption Angstrom exponents calculated from a pair of measured absorption coefficients at known wavelengths. The survey iteration method takes scattering and absorption coefficients, wavelength, and size distributions as inputs; and it calculates the Mie-equivalent wavelength dependent complex refractive index (RI = n +/- ik) and estimated errors. The retrieved field RI values ranged from 1.66 <= n <= 1.80 to 1.65 <= n <= 1.86 and from 0.036 <= k <= 0.038 to 0.062 <= k <= 0.067 in the wavelength range (400-550 nm), for low and high aerosol loading conditions, respectively. Additionally, we derived the spectral dependencies of scattering and absorption coefficients along with the n and k Angstrom exponents (AE). The nAE and kAE estimated values suggest a stronger wavelength dependence for aerosol light scattering compared to absorption, and a decreasing trend for the spectrally dependent single scattering albedo during both loading conditions. The extremum of errors in the retrieved n and k values were quantified by considering (a) uncertainties in input parameters in the broad spectral region (400-550 nm), (b) using CAPS extinction values at 530 nm and (c) an estimated size distribution incorporating the coarse particles (at 530 nm).

Tar balls are frequently found in slightly aged biomass burning plumes. They are spherical in shape, have diameters between similar to 100 and 300 nm, are amorphous and composed mostly of oxygen and carbon. Tar balls are light absorbing and considered to be a component of brown carbon. Tar balls have been typically reported and analyzed as individual spheres: however, in a recent study, we reported the presence of significant fractions of fractal-like aggregates made of several tar balls in fire plumes from different geographical locations. Aggregation affects the optical properties of particles; therefore, we use T-Matrix and Lorenz-Mie simulations to explore the effects of aggregation on the tar balls' optical properties in the 350 - 1150 nm wavelength range. We also evaluate the effects of different refractive indices available from the literature, different monomer numbers, and monomer sizes, as these are key factors determining the aggregates optical properties. Furthermore, we estimate the simple forcing efficiency for low and high surface albedos. Aggregates have a single scattering albedo (SSA) higher than that of individual tar balls (Delta SSA(550) (nm) up to 0.22). The hemispherical upscatter fraction of individual tar balls is more than 100% larger than for tar ball aggregates in many cases. The top of the atmosphere simple forcing efficiency over dark surfaces shows large variabilities with an increase up to similar to 53% for tar ball aggregates compared to individual tar balls. These results demonstrate that aggregation of tar balls can have a significant impact on their optical properties and radiative forcing. (C) 2019 Elsevier Ltd. All rights reserved.