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Recently, there has been a remarkable increase in rice production owing to genetic improvement and increase in application of synthetic fertilizers. For sustainable agriculture, there is dire need to maintain a balance between profitability and input cost. To meet the steady growing demands of the farming community, researchers are utilizing all available resources to identify nutrient use efficient germplasm, but with very little success. Therefore, it is essential to understand the underlying genetic mechanism controlling nutrients efficiency, with the nitrogen use efficiency (NUE) being the most important trait. Information regarding genetic factors controlling nitrogen (N) transporters, assimilators, and remobilizers can help to identify candidate germplasms via high-throughput technologies. Large-scale field trials have provided morphological, physiological, and biochemical trait data for the detection of genomic regions controlling NUE. The functional aspects of these attributes are time-consuming, costly, labor-intensive, and less accurate. Therefore, the application of novel plant breeding techniques (NPBTs) with context to genome engineering has opened new avenues of research for crop improvement programs. Most recently, genome editing technologies (GETs) have undergone enormous development with various versions from Cas9, Cpf1, base, and prime editing. These GETs have been vigorously adapted in plant sciences for novel trait development to insure food quantity and quality. Base editing has been successfully applied to improve NUE in rice, demonstrating the potential of GETs to develop germplasms with improved resource use efficiency. NPBTs continue to face regulatory setbacks in some countries due to genome editing being categorized in the same category as genetically modified (GM) crops. Therefore, it is essential to involve all stakeholders in a detailed discussion on NPBTs and to formulate uniform policies tackling biosafety, social, ethical, and environmental concerns. In the current review, we have discussed the genetic mechanism of NUE and NPBTs for crop improvement programs with proof of concepts, transgenic and GET application for the development of NUE germplasms, and regulatory aspects of genome edited crops with future directions considering NUE. [ABSTRACT FROM AUTHOR]

The cytochrome P450 (CYP) is a large and complex eukaryotic gene superfamily with enzymatic activities involved in several physiological and regulatory processes. As an objective, an in-silico genome-wide DNA methylation (5mC) analysis was performed in rice (Oryza sativa cv. Zhonghua11), and the epigenetic role of CYPs in two abiotic stresses was observed. Being a stable representative mark, DNA-methylation alters the gene expression under stressful environmental conditions. Rice plants under salinity and drought stresses were analyzed through MeDIP-chip hybridization, and 14 unique genes of the CYP family were identified in the rice genome with varying degrees of methylation. The gene structure, promoter sequences, and phylogenetic analysis were performed. Furthermore, the responses of CYPs to various abiotic stresses, including salinity, drought, and cold were revealed. Similarly, the expression profile of potential CYPs was also investigated under various phytohormone stresses, which revealed the potential involvement of CYPs to hormone regulations. Overall, the current study provides evidence for CYP's stress regulation and fundamental for further characterization and understanding their epigenetic roles in gene expression regulation and environmental stress regulation in higher plants. [ABSTRACT FROM AUTHOR]

The prohibitins (PHB) are SPFH domain-containing proteins found in the prokaryotes to eukaryotes. The plant PHBs are associated with a wide range of biological processes, including senescence, development, and responses to biotic and abiotic stresses. The PHB proteins are identified and characterized in the number of plant species, such as Arabidopsis, rice, maize, and soybean. However, no systematic identification of PHB proteins was performed in Solanum lycopersicum. In this study, we identified 16 PHB proteins in the tomato genome. The analysis of conserved motifs and gene structure validated the phylogenetic classification of tomato PHB proteins. It was observed that various members of tomato PHB proteins undergo purifying selection based on the Ka/Ks ratio and are targeted by four families of miRNAs. Moreover, SlPHB proteins displayed a very unique expression pattern in different plant parts including fruits at various development stages. It was found that SlPHBs processed various development-related and phytohormone responsive cis-regulatory elements in their promoter regions. Furthermore, the exogenous phytohormones treatments (Abscisic acid, indole-3-acetic acid, gibberellic acid, methyl jasmonate) salt and drought stresses induce the expression of SlPHB. Moreover, the subcellular localization assay revealed that SlPHB5 and SlPHB10 were located in the mitochondria. This study systematically summarized the general characterization of SlPHBs in the tomato genome and provides a foundation for the functional characterization of PHB genes in tomato and other plant species. [ABSTRACT FROM AUTHOR]

Organic amendments in the soil perform better than synthetic fertilizers in regards to soil fertility and sustainable crop productivity. Experiments were conducted to compare the effects of organic and synthetic fertilizers on soil fertility and wheat (Triticum aestivum L.) productivity. Soil fertility and protein contents of wheat grains (13.2% and 13.3% during 2005–06 and 2006–07, respectively) were improved by organic amendments. However, synthetic fertilizer (at the rate of 150, 100, and 60 kg ha−1 N, P2O5, and K2O, respectively) applications resulted in the maximum grain yield (4.05 and 4.46 t ha−1 during 2005–06 and 2006–07, respectively). The observed and simulated soil organic carbon (SOC) reasonably agreed during RothC model validation (R2 = 0.99). Economic analysis showed the maximum net profit and relative increase in income ($729 US ha−1 and 309%, respectively) from inorganic treatment. Application of synthetic fertilizers increased grain yield and farm profit while organic manure enhanced grain quality. The RothC model had potential for determining the SOC in organic farming under arid environment. [ABSTRACT FROM AUTHOR]

Biochar is the low-cost and environmental-friendly material which has shown a great potential for separation of heavy metals from water. The previous studies have established a superior role of biochar over other materials, such as activated carbon and inorganic sorbents (iron based) in efficient removal of toxic heavy metals from aqueous systems. Among the various factors influencing heavy metals sorption ability of biochar, types of feedstock/biomass and pyrolysis temperature play a significant role. The goal of this review is to increase our understanding of heavy metals sorption behavior by biochars – this is important as heavy metals sorption is driven based on biochar type, heavy metals species which involve numerous mechanisms, including the physical binding, complexation, ion exchange, surface precipitation and electrostatic interactions. In addition, this review paper describes various approaches to improve heavy metal sorption capacity of biochars by steam and acids/bases activations and impregnation of biochar-based composites with minerals, organic compounds and carbon-rich materials. The physical/chemical activation of biochars can improve the surface area, thus leading to their improved functionality, while modification/pretreatment methods help in synthesizing composites using biochar as a supporting media to develop new sorbents with efficient surface attributes for heavy metals removal from aqueous solutions. [ABSTRACT FROM AUTHOR]

This study demonstrates the reduction of nickel (Ni) toxicity and enhancing zinc (Zn) bioavailability from sunflower seed with biochar (BC) and chitosan (CH) application to Ni contaminated soil. The pH of experiment soil was adjusted to value 6.5 prior to its use in a greenhouse experiment. Acidified Ni contaminated soil was amended with Zn (4 mg kg−1 soil), while BC and CH, both as alone [1% each (w/w)] and in combination [0.5% each (w/w)], were used as immobilizing agents for Ni. Significantly higher concentrations of Zn were found in seed receiving ZnSO4 treatments. However, these results were more pronounced in the treatment (Zn+CH+BC) where Zn, CH, and BC were together applied. The Zn+CH+BC treatment improved seed quality parameters, phytate/minerals molar ratios, increased seed weight (per pot) up to 75%, Fe 41%, Zn 42% in seed, while reduced Ni concentration up to 17% in seed, over control. Similarly, Zn+CH+BC treatment significantly decreased oxidative stress by improving antioxidant defense system in sunflower. The results of this preliminary study suggest that further studies are obligatory to corroborate the extent of Ni immobilization in soil and enhancing Zn bioavailability from sunflower seed under field conditions with realistic and applicable rates of BC and CH. [ABSTRACT FROM AUTHOR]

Soil moisture and organic matter level affects soil respiration and microbial activities, which in turn impact greenhouse gas (GHG) emissions. This study was conducted to evaluate the effect of irrigation levels (75% [deficit], 100% [full], and 125% [excess] of reference crop evapotranspiration requirements), and organic amendments (OA) type (chicken manure [CM] and bone meal [BM]) and OA application rates (0,168, 336 and 672 kg total N ha−1) on (i) soil physical properties (bulk density, organic matter content and soil moisture content) and (ii) soil carbon dioxide (CO2) emissions from a highly weathered tropical Hawai'ian soil. Carbon dioxide readings were consistently taken once or twice a week for the duration of the cropping season. A drip irrigation system was used to apply the appropriate amount of irrigation water to the treatment plots. Treatments were randomly selected and corresponding organic amendments were manually incorporated into the soil. Plots were cultivated with sweet corn (Zea mays ‘SS-16’). Soil moisture content within and below the rootzone was monitored using a TDR 300 soil moisture sensor (Spectrum Technologies, Inc., Plainfield, IL, USA) connected with 12 cm long prongs. Soil bulk density and organic matter content were determined at the end of the cropping season. Analysis of variance results revealed that OA type, rate, and their interaction had significant effect on soil CO2flux (P< 0.05). Among the OA rates, all CM mostly resulted in significantly higher soil CO2fluxes compared to BM and control treatment (p< 0.05). The two highest rates of BM treatment were not significantly different from the control with regard to soil CO2flux. In addition, organic amendments affected soil moisture dynamics during the crop growing season and organic matter content measured after the crop harvest. While additional studies are needed to further investigate the effect of irrigation levels on soil CO2flux, it is recommended that in order to minimize soil CO2emissions, BM soil amendments could be a potential option to reduce soil CO2fluxes from agricultural fields similar to the one used in this study. [ABSTRACT FROM AUTHOR]

The presented manuscript addresses the quasi-static analysis of a dispersive coated radially uniaxial (RU) sphere placed in an unbounded chiral medium. Dispersion has been included through Lorentz–Drude model. RU medium is defined as having dyadic permittivity and/ or permeability. In this manuscript only permittivity of the sphere has been taken to be dyadic. Expressions for the internal fields of sphere have been calculated and discussed. The scattered fields response in terms of polarizability have been studied for different coated materials. Results of the given geometry compared with the results of special cases, dielectric sphere placed in free space and layered dielectric spheres placed in chiral medium for validation of results. [ABSTRACT FROM AUTHOR]

In recent decades, ambient gaseous pollution has increased due to anthropogenic activities worldwide. The studies to evaluate the adverse effects of ambient pollutants on commonly grown food crops are still limited, especially in Asian countries like Pakistan. The present study was conducted to measure the ambient pollutants in different sites of Faisalabad and their impact on growth and yield of wheat, mung bean and peas. Plants were grown in pots and placed at three sites named as control (Wire house of Government College University, Faisalabad), low pollution (LP) (Farm Area of Ayub Agricultural Research Institute) and high pollution (HP) (GT Chowk, Faisalabad) sites. Results showed that ambient ozone (O3) concentration was highest at HP site followed by LP site and was below AOT40 in control site. Ambient pollutants caused foliar injury in crops and decreased plant height, leaf area, biomass and grain yield. Pollutants caused a reduction in photosynthetic pigments, stomatal conductance and net photosynthetic rate and grain protein contents in all three crops. In conclusion, the ambient O3level was highest at HP site, this current O3level and other pollutants decreased the growth and yield of important food crops. [ABSTRACT FROM AUTHOR]

A pot experiment was conducted to evaluate the role of glycinebetaine (GB) in chromium (Cr) tolerance in mung bean (Vigna radiataL.) grown in Cr-stressed soil. Three concentrations of Cr (0, 250 and 500 µM) were tested with three (0, 50 and 100 mM) concentrations of foliar-applied GB. Cr alone led to a significant decrease in plant growth, biomass, and concentrations of chlorophyll a, b and carotenoids. Cr concentration and electrolyte leakage significantly increased in plants with increasing Cr levels in the soil. Lower Cr stress enhanced the activities of superoxide dismutase (SOD), peroxidases (POD) and catalase (CAT), while higher Cr concentrations decreased the activities of these enzymes. Foliar application of GB successfully alleviated toxic effects of Cr on mung bean and increased plant growth, biomass and chlorophyll contents under Cr stress. GB application reduced Cr accumulation and electrolyte leakage in plants and enhanced the activities of antioxidant enzymes in both shoots and roots as compared with Cr treatments alone. These findings suggest that foliar-applied GB alleviated Cr-induced oxidative stress in mung bean by reducing Cr uptake. The protective effect of GB against Cr stress varies with the concentrations of GB and Cr stress applied. Thus, further studies are still needed to specify the concentrations of GB required for detoxification of specific Cr concentrations under various climatic conditions. [ABSTRACT FROM AUTHOR]

This manuscript reports comparative study for the removal of health risk organic dye reactive blue 21 from aqueous solution using sorption and solubilization. Activated carbon was used as sorbent to remove dye. The bath sorption experiments were carried out at different pH, sorbent dosage, contact time, initial concentration, and agitation speed. The applicability of the Langmuir and Freundlich isotherm models was examined. The influence of cationic surfactant, cetyltrimethyl ammonium bromide (CTAB), and an anionic surfactant, sodium dodecyl sulfate (SDS) on spectral properties of selected dye in aqueous solutions was investigated by means of UV–Visible spectroscopy in sub-micellar and micellar concentration range. Absorption spectra of this dye in the presence of surfactants may confirm which type of interaction is possible between molecules of dye and surfactants. It is expected that initially molecules of dye may attach with monomeric molecules of surfactant in premicellar region while in post-micellar region they are accommodated within micelle. The values of micelle–water partition coefficient, Kx, free energy of partition, ΔGx, of RB21 between bulk water and micelles, drug-surfactant binding constant, Kb, and free energy of binding, ΔGb, were calculated from differential spectroscopic data. [ABSTRACT FROM PUBLISHER]

Land application of biosolids from processed sewage sludge may deteriorate soil, water, and plants. We investigated the impact of the N-Viro biosolids land-application on the quality of the soil water that moved through Orthic Humo-Ferric Podzols soil of Nova Scotia (NS) at the Wild Blueberry Research Institute, Debert, NS Canada. In addition, the response of major soilproperties and crop yield was also studied. Wild blueberry (Vaccinium angustifolium. Ait) was grown under irrigated and rainfed conditions in 2008 and 2009. Four experimental treatments including (i) NI: N-Viro irrigated, (ii) NR: N-Viro rainfed, (iii) FI: inorganic fertilizer irrigated, and (iv) FR: inorganic fertilizer rainfed (control) were replicated 4 times under randomized complete block design. Soil samples were collected at the end of each year and analyzed for changes in cation exchange capacity (CEC), soil organic matter (SOM), and pH.Soil water samples were collected four times during the study period from the suction cup lysimeters installed within and below crop root zone at 20 and 40 cm depths, respectively. The samples were analyzed for a range of water quality parameters including conductance, hardness, pH, macro- and micronutrients, and the infectious pathogens Escherichia coli (E. coli) and salmonella. Berries were harvested for fruit yield estimates. Irrigation significantly increased CEC during 2008 and the soil pH decreased from 4.93 (2008) to 4.79 (2009). There were significant influences of irrigation, fertilizer, and their interaction, in some cases, on most of the soil water quality parameters except on the infectious bacteria. No presence of E. coli or salmonella were observed in soil and water samples, reflecting the absence of these bacteria in biosolids used in this experiment. Nutrient concentration in the soil water samples collected from the four treatments were higher in the sequence NI > NR > FI > FR. The irrigation treatment had significant effect on the unripe fruit yield. We conclude that the comparable performance of N-Viro biosolids and the increasing prices of inorganic fertilizers would compel farmers to use economically available N-Viro biosolids that, coupled with the supplemental irrigation, did not deteriorate the studied soil properties, soil water quality, and the wild blueberry yield during this experiment. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effects of chicken manure (CM) application rates on nutrient concentrations within and below the root zone of sweet corn (Zea mays L. subsp. mays) under Hawaiian conditions. The research was conducted in leeward (Poamoho) and windward (Waimanalo) areas of Oahu, Hawaii, where contrasts exist in both climatic and soil conditions. Suction cup were used to collect soil solutions from 30 and 60 cm depths. Soil solutions were collected six times during the growing season at each location and analyzed for different nutrients (N, P, K, Ca, Mg, Na, Fe, Mn, Zn, and Cu), nitrate-nitrogen (NO3-N), ammonium-nitrogen (NH4-N), electrical conductivity (EC), and pH. Analysis showed that CM rates significantly affected the concentration of macro-nutrients below the root zone at Poamoho and within the root zone at Waimanalo. In general, nutrient concentration increased with the increasing rates of CM application. There was a significant effect of CM on micro-nutrients except below the root zone at Poamoho. CM significantly affected NO3-N concentration within the root zone for 15, 60 days after planting (DAP) at Poamoho, and 16, 28 DAP at Waimanalo. The effect was also significant on total nitrogen (N) concentration in the root zone across the two growing seasons at Waimanalo. There was a highly significant correlation between total N and NO3-N, and EC within and below the root zone. [ABSTRACT FROM AUTHOR]

Focuses on the derivation of expressions for the radiation Q-factor of a high-temperature superconducting parallel-plate half-wavelength open-ended resonator. Effect of frequency; Design of ultra-high Q-factor resonators.