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The impacts of the feedstock types and their blending ratios on pellet formation and system performance were studied. The pellet manufacturing facilities were simulated encompassing all processes from farm-level raw material supply to the production of the final product and its sale at the factory gate. Each model scenario is broken down into four sections: transportation of the feedstock, pre-processing, conversion to pellets, and storage of the final product. Simulations of relevant unit operations were carried out for all plant activities using the required technical information, such as operating size, number of components, materials for construction, and operational characteristics. Four simulation scenarios were selected for study, termed plant-1, plant-2, plant-3, and plant-4. Parameters were assessed by varying the costs of pelletizer, grinder, shredder, binder, feedstock, labor, utility, and revenue selling price by ± 10% and ± 20% from their current market prices, considered a base value. Capital investment ranges from $404,000 to $468,000, with plant-2 (100% SD at 15% binder and 15% moisture content (MC)) having the lowest value and plant-4 (75% SD + 25% CC at 15% binder and 20% MC) having the highest value. The operating cost (OC) of plant-3 (100% CS at 15% binder and 20% MC) was found to be the lowest, while plant-1 (100% SD at 20% binder and 20% MC) is the highest due to the higher percentage of binder having a high drying cost as well as a high procurement cost. Pellets are the main revenue stream obtained from all plants. Plant-3 is observed as the most economical among all plants, having the highest value of gross margin (GM), highest internal rate of return (IRR), highest net present value (NPV), highest percentage of return on investment (ROI), lowest operating cost (OC), and lowest payback time (PBT) of 6.54%, 11.96%, $15,8000, 18.67, $954,000, and 5.36 years, respectively. Sensitivity analysis shows that the cost of binder, the cost of feedstock, and labor costs have influential effects on input costs. Pellet selling price is the most influential factor affecting economic returns.

Heat spell during the reproductive growth of wheat is a serious threat to achieve food security. An experiment was conducted with the objectives (i) to explore the optimum dose of foliar selenium for alleviation of heat, (ii) to investigate the thermo-lability of reproductive stages of wheat, (iii) to enquire about the correlation of biochemical attributes with agronomic traits, and (iv) to determine the economic feasibility of foliar selenium for alleviation of adverse impacts of heat on wheat. The study was conducted over 2 years using a split treatment structure in a randomized complete block design. Treatments were comprised of H0(control), H1(heat imposition from spike to grain filling), and H2(heat imposition from flowering to grain filling). Foliar doses of selenium (Se), viz., Se0= water spray (control); Se25= 25 mg Se L−1; Se50= 50 mg Se L−1; Se75= 75 mg Se L−1and Se100= 100 mg Se L−1were maintained in sub plots. The longer heat spell proved more deleterious than the shorter one. More catalase, glycine betaine, water potential, turgor potential, grain filling rate, spikelets per spike, grains per spike, and grain yield were recorded with 75 mg Se L−1under “H0,” while remarkably higher responses of these attributes were observed with 100 mg Se L−1under “H1” and “H2.” Based on marginal analysis, applying “75 mg Se L−1” resulted in higher economic benefits under “H0” and “H1,” whereas 50 mg L−1was more economical to apply under “H2.” Moreover, strong associations of physiochemical attributes with agronomic traits were observed. Decisively, applying “75 mg Se L−1” on terminally heat-stressed wheat produced more benefits compared to other doses.

High temperature stress during reproductive stages of wheat is a leading constraint in achieving food security. The objectives of study were to investigate heat sensitivity of terminal stages of wheat, to optimize foliar selenium dose, to boost nonenzymatic antioxidants and to determine correlation of these nonenzymatic antioxidants with yield and quality attributes of wheat crop. The field experiment was conducted for two consecutive years at agronomic research area, University of Agriculture Faisalabad, Pakistan. It was laid out in a randomized complete block design under split arrangement, and treatments were replicated thrice. Main plot factor comprised of heat imposition treatments; H0= Control; H1= Heat from spike to grain filling; H2= Heat from flowering to grain filling while in subplots doses of foliar selenium were maintained; Se0= Control (water spray); Se25= 25 mg L−1; Se50= 50 mg L−1; Se75= 75 mg L−1and Se100= 100 mg L−1. Impact of H1was more damaging compared to H2and H0for all response variables. Higher levels of proline, phenolics and leaf selenium were recorded with foliar spray of selenium either at 75 or at 100 mg L−1under H0, whereas under H1and H2, significantly higher responses were observed with 100 mg L−1selenium for these traits. Increases in leaf chlorophyll and grain protein contents were statistically alike with 75 and 100 mg L−1selenium; while in case of 1000-grain weight, harvest index and grain yield three levels of foliar selenium (50, 75 and 100 mg L−1) performed equally well under all the three heat stress treatments. Moreover, strong positive and significant associations of proline, phenolics, leaf selenium and chlorophyll were measured with yield of wheat. Conclusively, more harmful impacts were recorded under H1compared to H2and H0; while 75 mg L−1Se proved more beneficial under H0and 100 mg L−1Se under H1and H2. Strong associations of biochemical and agronomic traits were observed.

High temperature during reproductive stages of cotton is a major constraint to achieve potential yield of cotton. The aim of the present study was to determine comparative thermo-sensitivity of squaring and flowering, to optimize exogenous selenium for heat-stressed cotton, and to explore correlation among physiochemical and morphological attributes. The experiment was conducted during 2013 and repeated during 2014. The experiment was laid out in randomized complete block design under split plot arrangement and replicated thrice. Treatments were comprised of heat stress (H0= no heat imposition; H1= heat imposition at squaring; and H2= heat imposition at flowering) in main plot and varying foliar selenium concentrations (Se0= water spray/control; Se50= 50; Se100= 100; and Se150= 150 mg L-1selenium) in split plot. Significantly, more antioxidants, chlorophyll contents, water relation attributes, seed cotton yield, and lesser hydrogen peroxide were recorded with 150 mg L-1foliar selenium compared with other concentrations under H0. While under H1and H2, statistically similar and significantly more antioxidants, chlorophyll contents, water relation attributes, seed cotton yield, and lesser hydrogen peroxide were observed for 100 and 150 mg L-1selenium compared with other selenium concentrations. Conclusively, H2proved more thermolabile compared with H1, and application of 150 mg L-1foliar selenium effectively alleviated adverse effects of heat. Moreover, we observed strong and significant associations of all physiochemical attributes with seed cotton yield.

Agricultural production systems are immensely exposed to different environmental stresses in which heavy metal stress receives serious concerns. This study was conducted to explore the deleterious effects of different chromium (Cr) stress levels, i.e., 0, 30, 60, 90, 120, and 150 μmol L−1, on two maize genotypes, Wandan 13 and Runnong 35. Both genotypes were evaluated by measuring their growth and yield characteristics, Cr accumulation in different plant tissues, alterations in osmolyte accumulation, generation of reactive oxygen species (ROS), and anti-oxidative enzyme activity to scavenge ROS. The results showed that Cr stress decreased the leaf area, cob formation, 100-grain weight, shoot fresh biomass, and yield formation, while Cr accumulation in different maize tissues was found in the order of roots > leaves > stem > seeds in both genotypes. The increased Cr toxicity resulted in higher free proline, soluble sugars and total phenolic contents, and lower soluble protein contents. However, enhanced lipid peroxidation was noticed in the forms of malondialdehyde, hydrogen peroxide (H2O2) and thiobarbituric acid reactive substance accumulation, and electrolyte leakage. The hyperactivity of superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, especially glutathione peroxidase and glutathione reductase indicated that these anti-oxidative enzymes had a central role in protecting maize from Cr toxicity, especially for Wandan 13. Moreover, higher uptake and less translocation of Cr contents into the grains of Wandan 13 implied its importance as a potential candidate against soil Cr pollution.

Water deficit is an environmental constraint restricting plant growth and productivity, and is further worsened by reduced soil fertility. Plant growth-regulating substances ameliorate damaging effects of abiotic stresses, and their efficacy is improved by application of adequate nutrients. An experiment was undertaken to investigate the influence of foliar-applied nutrients (nitrogen, phosphorus, potassium: NPK) and 5-aminolevulinic acid (ALA) alone and in combination on morpho-physiological indices of the perennial grass Leymus chinensis (Trin.) Tzvel under drought and well-watered conditions. Drought stress caused a reduction in growth and photosynthetic pigments while increasing the accumulation of malondialdehyde (MDA) and osmolytes compared with well-watered conditions. However, application of NPK and ALA improved plant height, fresh and dry weights, and chlorophyll content. Production of soluble proteins and sugars, proline content, and antioxidant enzyme activities (superoxide dismutase, peroxidase, catalase, ascorbate peroxidase and glutathione reductase) were increased and MDA accumulation was lowered by application of NPK and ALA relative to the control (no application). Combined application of NPK and ALA proved more advantageous than NPK or ALA alone in exerting ameliorative effect on L. chinensis under drought-stressed conditions. The results suggest that combined application of NPK and ALA improves the growth and development of L. chinensis by modulating physiological processes and aids in sustaining drought.