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Sustainable agricultural production is mainly attributed to healthy soils. Calcareous soils, especially in arid and semiarid areas, suffer from low organic matter and nutrient availability. Low organic matter could degrade soil with reducing the crop productivity. Thus, the present study aimed to assess the integrated effect of soil mulch and irrigation on soil activity, nutrient availability, and potentiality of corn yield under calcareous soil conditions. In a calcareous soil, two mulching soil treatments (mulch and non-mulch) as well as three irrigation regimes, applied as ratio of crop evapotranspiration (60, 80, and 100%, denoted I60, I80, and I100, respectively), were arranged in a strip plot design based on completely randomized block arrangement using 3 replicates. Mulching soil plus irrigation by I80 achieved the maximum increases in organic carbon, organic matter, and soil activity. Higher values of NH 4 + -N form were detected with non-mulch and irrigation by I100 or I60. Lower Zn content was obtained in soil due to mulch or non-mulch plus irrigation I100. With lowering irrigation level by 20% (I80) and by application of mulch, the increases in weight of ear, weight of 100 kernels, and kernel yield of corn amounted to 5.4, 4.6, and 16.1%, respectively. Results from the present study conclude that adoption of soil mulching in corn production system plus moderate irrigation (80% of crop evapotranspiration) is considered a promising management practice for amending calcareous soils, saving irrigation water, and sustaining/boosting soil productivity in arid zones.

Egypt Crop plants treated with silicon (Si) can overcome the injury impacts of several stress conditions. However, scarce information is available about the significance of Si for helping the plants to overcome the injuries of low nitrogen (N) supply and herbicide pressure. A 2-year field experiment was carried out for evaluating four combinations of fenoxaprop-p-ethyl and Si: fenoxaprop-p-ethyl + Si 250ppm and fenoxaprop-p-ethyl + Si 500ppm (each either in sequence or in a tank mixture), in addition to fenoxaprop-p-ethyl alone, hand weeding, and weed check under two N levels (N 100% and N 50% ). Silicon can mitigate the reduction in wheat yield but has no effect on weeds when applied with fenoxaprop-p-ethyl. When adding N 50% , sequential application of fenoxaprop-p-ethyl + Si 250ppm along with hand weeding and other fenoxaprop-p-ethyl + Si treatments, except fenoxaprop-p-ethyl alone, were the most promising for improving grain yield.

Wheat productivity is severely hampered by drought, owing to its negative impacts on crop growth and development. For obtaining better yield, the impacts of drought should be ameliorated. Therefore, the current study scrutinizes the potential of different silicon (Si) forms to minify the drought-associated reduction in yield and the changes in nutrients accumulation. In a strip plots design based on randomized complete block arrangement using 3 replicates, two field experiments were carried out in 2019/20 and 2020/21 seasons. Three silicon (Si) forms (potassium silicate, calcium silicate, and aluminum silicate), in addition to the control (tap water) were sprayed. Also, three irrigation regimes were applied as ratio of crop evapotranspiration (60, 80 and 100%, denoted Irr60, Irr80 and Irr100, respectively). Findings clarified that application of aluminum silicate in both seasons, in addition to calcium silicate in the second season recorded the maximum accumulation of Si in wheat plants. Supplying wheat plants with different forms of Si reduced zinc (Zn) and manganese (Mn) and increased Si compared to the control (no Si application). Irr100 possessed increase in accumulation of Si in plant tissues greater than Irr80 or Irr60. Significant increases in all agronomic traits of wheat were obtained owing to spraying any Si form compared to the control. The differences between potassium silicate, calcium silicate, and aluminum silicate were not significant in flag leaf greenness (SPAD value), grains weight spike−1, weight of 1000 grains, and grain yield ha−1 in 2020/21 season. Irr100 was the effective treatment for enhancing SPAD value, spike length, grains weight spike−1, weight of 1000 grains, and grain yield ha−1. When irrigation water was reduced by 20% (Irr80), the lowest reduction in grain yield was obtained with potassium silicate compared to other forms of Si. It could be concluded that since lower accumulation of Si in plant tissues under water deficit than well-watered was recorded, the spraying of Si is great of importance to be applied under drought stress.

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Many studies have identified various risk factors associated with Covid-19, for example, individuals with comorbidities are at an increased risk of contracting the disease and developing severe symptoms than those without comorbidities, however, these findings are inconsistent. This study identifies various risk predictors of Covid-19 patients with and without comorbidities. Data of Covid-19 patients was retrieved from Patient Digital Library of Shalamar Hospital, Lahore and encompassed patients’ gender, age, symptoms and severity besides other vitals. Data of total 1,639 patients who were admitted at Pulmonology Unit of Shalamar Hospital was examined. Out of this, 180 Covid-19 patients were recruited for final analyses as they were fully in accordance with the eligibility criteria framed for this study. Of these, 137 were suffering from comorbidities and the analysis revealed that these comorbidities had significant effect on the end result of the Covid-19 illness (P=0.002) i.e. the mortality rate among the patients with comorbidities was found to be 33.6% (n=46) and that of patients with no comorbidities was 9.3% (n=4). Likewise, the recovery rate of patients without comorbidities was significantly high (90.7%, n=39). However, interestingly, presence or absence of comorbidities had no significant impact on severity of the disease. Moreover, O2 saturation < 90% is predicted as a risk factor of severity whereas age > 59, presence of comorbidities and severe symptoms are found to be the risk predictors for the outcome of the disease being recovered or expired.

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