Osmopriming with PEG has potential to improve seed germination, seedling emergence, and establishment, especially under stress conditions. This research investigated germination performance, seedling establishment, and effects of osmopriming with PEG on physiology in sorghum seedlings and their association with post-priming stress tolerance under various soil moisture stress conditions. Results showed that seed priming increased the environmental range suitable for sorghum germination and has potential to provide more uniform and synchronous emergence. Physiologically, seed priming strengthened the antioxidant activities of APX, CAT, POD, and SOD, as well as compatible solutes including free amino acid, reducing sugar, proline, soluble sugar, and soluble protein contents. As a result, seed priming reduced lipid peroxidation and stabilized the cell membrane, resulting in increased stress tolerance under drought or excessive soil moisture environments. Overall, results suggested that seed priming with PEG was effective in improving seed germination and seedling establishment of sorghum under adverse soil moisture conditions. Osmopriming effectively strengthened the antioxidant system and increased osmotic adjustment, likely resulting in increased stress tolerance.

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Herein, we studied the combustion and pyrolysis for miscanthus × giganteus (Elephant Grass) using TG/DSC techniques. Currently, miscanthus is used to an extent in energy generation applications however; issues with regards to its physicochemical combustion characteristics currently hinder this uptake. In this work, the thermal and kinetic analysis of dry miscanthus and its char were investigated for a better understanding of its physicochemical combustion characteristics and consequently, achieving the highest benefit from the combustion process. Different kinetic modeling has been used to calculate the activation energy and the kinetic parameters during combustion/pyrolysis such as the ASTM-E698, Flynn-Wall and Ozawa (FWO) and differential iso-conversional methods. It was observed that the activation energy values were 22.3, 40-150 and 40-165 kJ mol-1 for miscanthus, respectively. Furthermore, miscanthus species were tested in wastewater treatment and showed a potential for the rapid removal of cadmium heavy metal. In addition, a study of miscanthus ash was performed and indicated that it can be used as a source of potassium in the fertiliser industry.

The efficacy of WSSA Group 4 herbicides has been reported to vary with dependence on the time of day the application is made, which may affect the value of this mechanism of action as a control option and resistance management tool for Palmer amaranth. The objectives of this research were to evaluate the effect of time of day for application on 2,4-D and dicamba translocation and whether or not altering translocation affected any existing variation in phytotoxicity seen across application time of day. Maximum translocation (Tmax) of [14C]2,4-D and [14C]dicamba out of the treated leaf was significantly increased 52% and 29% to 34% in one of two repeated experiments for each herbicide, respectively, with application at 7:00 AM compared with applications at 2:00 PM and/or 12:00 AM. Applications at 7:00 AM increased [14C]2,4-D distribution to roots and increased [14C]dicamba distribution above the treated leaf compared with other application timings. In phytotoxicity experiments, dicamba application at 8 h after exposure to darkness (HAED) resulted in significantly lower dry root biomass than dicamba application at 8 h after exposure to light (HAEL). Contrasts indicated that injury resulting from dicamba application at 8 HAEL, corresponding to midday, was significantly reduced with a root treatment of 5-[N-(3,4-dimethoxyphenylethyl)methylamino]-2-(3,4-dimethoxyphenyl)-2-isopropylvaleronitrile hydrochloride (verapamil) compared with injury observed with dicamba application and a root treatment of verapamil at 8 HAED, which corresponded to dawn. Overall, time of application appears to potentially influence translocation of 2,4-D and dicamba. Furthermore, inhibition of translocation appears to somewhat influence variation in phytotoxicity across times of application. Therefore, translocation may be involved in the varying efficacy of WSSA Group 4 herbicides due to application time of day, which has implications for the use of this mechanism of action for effective control and resistance management of Palmer amaranth.

Miscanthus species originated in Asia and were imported into Europe and North America as ornamental plants. They are perennial rhizomatous grasses with lignified stems and present very high growth rates, even in more temperate maritime climates. This potentially abundant biomass offers benefits to many sectors and is used to an extent in energy generation applications, however, issues with regards to its physicochemical combustion characteristics currently hinder this uptake. In this work, a novel alternative application, namely its direct use of dry miscanthus (DM) plant as an adsorbent for heavy metals removal (HMR) from wastewaters, was investigated. The physical, chemical, and leaching properties of DM were analyzed using XRD, SBET, TGA, DSC, SEM‐EDX, elemental analysis, halogen, and ICP techniques. Subsequently, the HMR capacity of miscanthus was studied for lead, copper, and zinc from aqueous solutions. Results showed a high percentage removal of 66%, 83%, and 88%, respectively, with the majority being removed during the first hour of the test. Overall the results show that DM plant can be effectively utilized in wastewater treatment. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 1058–1067, 2018

Saline‐sodic water is a by‐product of coalbed natural gas (CBNG) production in the Powder River Basin of Wyoming, USA and is being beneficially used in places as irrigation water. This study evaluated effects of 2 years of natural precipitation on soil properties of a hay field after the cessation of managed irrigation with CBNG water. The hay field had been irrigated with only CBNG water [CBNG(NT)], CBNG water amended with gypsum [CBNG(G)] or gypsum plus sulfur via a sulfur burner [CBNG(GSB)] in combination with soil amendments—gypsum (+G), elemental sulfur (+S), and both (+GS). Results indicated that infiltration rates were the lowest on fields irrigated with CBNG(NT), followed by CBNG(G) and CBNG(NT)+G treatments (12·2, 13·2, and 13·5 cm h−1, respectively). The CBNG(GSB)+GS treatment had the highest infiltration rates (33·5 cm h−1). By the second year, salinity and sodicity of treated soils had decreased in the A‐horizon of most CBNG‐water irrigated plots, whereas in Bt1‐ and Bt2‐horizons salinity generally decreased but sodicity increased; S and GS soil amended plots had higher profile salinities compared with NT and G soil treatments. Although Na+ leaching was observed in all fields that received soil and/or water amendments, CBNG(GSB)+GS plots had the lowest sodicity in the A‐ and Bt1‐horizons. Effective managed irrigation requires knowledge of site‐specific soil properties, plant suitability, water chemistry, and amendments that would be needed to treat the CBNG waters and soils. This study indicates the greatest success was realized when using both soil and water amendments. Copyright © 2011 John Wiley & Sons, Ltd.

Relationships between electrical conductivity (EC) and sodium adsorption ratio (SAR) in reconstructed soils at surface coal mining operations are poorly documented in the literature. Research has focused primarily on agricultural and range soils. Chemical and physical properties of reconstructed soils are unique and quite different from natural soils formed over hundreds of years through pedogenic processes. These differences largely occur because relatively unweathered overburden is exposed during mining processes and subsequently used as a lower root-zone medium (minesoil) during soil reconstruction. Some of these materials are classified as sodic and therefore are considered unsuitable rooting media for establishment of native vegetation. Weatherable minerals (i.e., pyrite, calcite, gypsum, and other geologic substrates) present in minesoils can effectively remediate or mitigate an elevated SAR condition by maintaining EC levels in the soil solution to promote clay particle stability and by providing sources of exchangeable calcium and magnesium. Coversoil (e.g., topsoil) enhances remediation through physical and chemical buffering between sodic root-zone material and the reconstructed soil surface. A laboratory core-study was used to evaluate weathering potential of 10 minesoil materials from three mining operations in the Southwestern United States. Cores were prepared with 15 cm of coversoil over 30 cm of minesoil and subjected to simulated precipitation. Chemical evaluations of weathered materials show significant reductions in EC and SAR and overall improvement of minesoil quality. Chemistry of drainage water from three coversoils shows these materials behave as a chemical buffer above the underlying sodic materials. Coversoils provide a source of calcium and other electrolytes that promote physical stability and enhance remediation of sodic minesoil materials.

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