Hormonal changes, growth and yield of tomato plants in response to chemical and bio-fertilization application in sandy soils

The response of tomato plants to chemical and bio-fertilization under sandy soil conditions was investigated. The experiments were conducted in Nubaria region, Egypt. Tomato plants were treated with Microbein or a mixture of Phosphorine and Biogein as bio-fertilizers under different rates of the recommended nitrogen and phosphorus fertilization (100% of N and P, 75% of N and P and 50% of N and P). In addition, plants of three treatments received only the rates of chemical fertilizers and were not treated with the bio-fertilizers. Vegetative growth measurements, yield, hormonal changes in leaves, and N, P and K contents of leaves were recorded to study the effects of these treatments. The results showed that bio-fertilization significantly increased the vegetative growth of tomato plants (including plant height, number of branches, number of leaves and the fresh weight of plants) and yield compared to non-treated plants. Growth and yield of tomato plants was negatively affected by the low chemical fertilization treatments especially at 50% of N and P while biofertilization enhanced growth and productivity under such conditions. Tomato plants which were treated with a mixture of Phosphorine and Biogein had higher growth and yield than plants treated with Microbein. Bio-fertilization resulted in higher N, P and K contents of leaves and higher indole acetic acid (IAA), Gibberellins (GA3) and Cytokinins. The possible effects of the treatments are discussed

Drought tolerance and water status of bean plants (Phaseolus vulgaris L.) as affected by citric acid application

   Enhancement of drought tolerance of plants is a crucial concern in arid and semi-arid regions. Using safe and environmentally-friendly tools and treatments for this purpose is needed to overcome the problems of water shortage with particular emphasis on sustainable resource management and environmental protection. This study investigated the water status and drought tolerance of beans. Bean plants (Phaseoulus vulgaris L.) were treated with citric acid (0.5, 1, 1.5 and 2 g/L) as a foliar application prior the exposition to drought stress conditions. Physiological changes, such as leaf temperature, relative water content (RWC) and chlorophyll content of leaves, were recorded in response to citric acid application. The results revealed that the water status of bean plants under drought stress conditions was improved by citric acid application, indicated by higher RWC of leaves compared to control plants. The most effective level in this respect was 1.5 g/L. A similar trend was observed with total chlorophyll content of leaves. In addition, plant growth, productivity and quality parameters were significantly improved by application of citric acid compared to control plants. The possible roles of citric acid on water status and drought tolerance of bean plants are discussed

Highly Efficient One-pot Synthesis, Antimicrobial and Docking Studies of Newer β-amino Carbonyl Derivatives Catalyzed by Silica Sulfuric Acid

Mannich reaction was applied between 4-fluorobezaldehyde, selected acetophenone and several anilines, catalyzed by silica sulfuric acid for the synthesis of β-amino carbonyl derivatives. Reaction time and yield of the products depended on the nature of acetophenone and aniline subsituents. Using aliphatic amines instead of aromatic amines under same reaction conditions, afforded aldol condensation products without yielding the expected β-amino ketones. Replacing the acetophenone derivatives with rhodanine yielded 5-(4-fluorobenzylidene)-thioxothiazolidin-4-one. Using 2-aminothiophenol instead of the aniline derivatives, 2-(4-fluorophenyl)benzothiazole was obtained without isolation of the expected (mercapto-phenylamino)-1-(4-substitutedphenyl)propan-1-ones. A proposed reaction mechanism was suggested. Docking studies were designed to gain clear picture of the high active compound(s). A model of high active molecules was mapped for the antimicrobial screening and compared with least active compound(s). (doi: 10.5562/cca1983

Tomato yield, physiological response, water and nitrogen use efficiency under deficit and partial root zone drying irrigation in an arid region

Water scarcity in arid regions is a serious problem, which calls for innovative irrigation water management. Partial root zone drying (PRD) technique can considerably reduce irrigation amount for crops. To investigate this further, tomato plants were imposed to either surface drip (SUR) with full irrigation (FI) at 100% of evaporative demands and regulate deficit irrigation (RDI) at 50% water of FI or subsurface drip irrigation (SDI) with fixed PRD at 75 (PRD75) and 50% (PRD50) of the FI. Surface evaporation under SUR with FI constitutes a large fraction of water losses from cropped fields while SDI with PRD75 preserved more water for plant uptake. Plants grown under water saving treatments showed lower stomatal conductance and transpiration rates compared to FI plants. Tomato yield under SDI with PRD75 was comparable to yield under SUR with FI for both tested seasons along with 25% water saving and 30% increase in water use efficiency (WUE). Otherwise, PRD50 reduced yield by 18-20%, but a substantial amount of irrigation water was saved along a 60 and 65% higher WUE compared to FI treatment. Fruit dry weight and harvest index (HI) were significantly higher with PRD75 compared to the other treatments. Seasonal N uptake and in turn N recovery was higher in PRD75 than any other treatment associated with improving N use efficiency

Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020

Deficit Irrigation and Arbuscular Mycorrhiza as a Water-Saving Strategy for Eggplant Production

Crop production in arid regions requires continuous irrigation to fulfill water demand throughout the growing season. Agronomic measures, such as roots-soil microorganisms, including arbuscular mycorrhizal (AM) fungi, have emerged in recent years to overcome soil constraints and improve water use efficiency (WUE). Eggplant plants were exposed to varying water stress under inoculated (AM+) and non-inoculated (AM−) to evaluate yield performance along with plant physiological status. Plants grown under full irrigation resulted in the highest fruit yield, and there were significant reductions in total yield and yield components when applying less water. The decline in fruit yield was due to the reduction in the number of fruits rather than the weight of the fruit per plant. AM+ plants showed more favorable growth conditions, which translated into better crop yield, total dry biomass, and number of fruits under all irrigation treatments. The fruit yield did not differ between full irrigation and 80% evapotranspiration (ET) restoration with AM+, but a 20% reduction in irrigation water was achieved. Water use efficiency (WUE) was negatively affected by deficit irrigation, particularly at 40% ET, when the water deficit severely depressed fruit yield. Yield response factor (Ky) showed a lower tolerance with a value higher than 1, with a persistent drop in WUE suggesting a lower tolerance to water deficits. The (Ky) factor was relatively lower with AM+ than with AM− for the total fruit yield and dry biomass (Kss), indicating that AM may enhance the drought tolerance of the crop. Plants with AM+ had a higher uptake of N and P in shoots and fruits, higher stomatal conductance (gs), and higher photosynthetic rates (Pn), regardless of drought severity. Soil with AM+ had higher extractable N, P, and organic carbon (OC), indicating an improvement of the fertility status in coping with a limited water supply

The Influence of Foliar Application of Potassium on Yield and Quality of Carrot (Daucus carota L.) Plants Grown under Sandy Soil Conditions

Abstract: The experiments were conducted under sandy soil conditions in Nubaria (west delta region) to study the response of carrot plants to foliar application of potassium. Different levels of foliar potassium fertilizer (0.5, 1, 1.5 and 2ml/L) were applied. Plant growth, productivity, root quality and chemical analysis of leaves (N, P and K) were recorded in response to the application of these treatments. The results showed that carrot plants responded positively to all K levels. Vegetative growth parameters (including plant height, number of leaves and fresh and dry weight of leaves) were significantly enhanced by the levels of K especially at the higher levels while control plants obtained the lowest values. The level 1.5 ml/L seems to be optimal for carrot plants as increasing the K level more than this level did not give significant increment. Similar results were observed concerning root length, diameter, fresh and dry weight of roots and total soluble solids (T.S.S.) in roots. Results concerning the chemical analysis of carrot leaves are discussed. The results indicated that foliar application of K under sandy soil conditions improved root quality as well

The Influence of Foliar Application of Potassium on Yield and Quality of Carrot (Daucus carota L.) Plants Grown under Sandy Soil Conditions

Abstract: The experiments were conducted under sandy soil conditions in Nubaria (west delta region) to study the response of carrot plants to foliar application of potassium. Different levels of foliar potassium fertilizer (0.5, 1, 1.5 and 2ml/L) were applied. Plant growth, productivity, root quality and chemical analysis of leaves (N, P and K) were recorded in response to the application of these treatments. The results showed that carrot plants responded positively to all K levels. Vegetative growth parameters (including plant height, number of leaves and fresh and dry weight of leaves) were significantly enhanced by the levels of K especially at the higher levels while control plants obtained the lowest values. The level 1.5 ml/L seems to be optimal for carrot plants as increasing the K level more than this level did not give significant increment. Similar results were observed concerning root length, diameter, fresh and dry weight of roots and total soluble solids (T.S.S.) in roots. Results concerning the chemical analysis of carrot leaves are discussed. The results indicated that foliar application of K under sandy soil conditions improved root quality as well

Ionophore-Based Polymeric Sensors for Potentiometric Assay of the Anticancer Drug Gemcitabine in Pharmaceutical Formulation: A Comparative Study

Gemcitabine is a chemotherapeutic agent used to treat various malignancies, including breast and bladder cancer. In the current study, three innovative selective gemcitabine hydrochloride sensors are developed using 4-tert-butylcalix-[8]-arene (sensor 1), β-cyclodextrin (sensor 2), and γ-cyclodextrin (sensor 3) as ionophores. The three sensors were prepared by incorporating the ionophores with o-nitrophenyl octyl ether as plasticizer and potassium tetrakis(4-chlorophenyl) borate as ionic additive into a polyvinyl chloride polymer matrix. These sensors are considered environmentally friendly systems in the analytical research. The linear responses of gemcitabine hydrochloride were in the concentration range of 6.0 × 10−6 to 1.0 × 10−2 mol L−1 and 9.0 × 10−6 to 1.0 × 10−2 mol L−1 and 8.0 × 10−6 to 1.0 × 10−2 mol L−1 for sensors 1, 2, and 3, respectively. Over the pH range of 6–9, fast-Nernst slopes of 52 ± 0.6, 56 ± 0.3, and 55 ± 0.8 mV/decade were found in the same order with correlation regressions of 0.998, 0.999, and 0.998, respectively. The lower limits of detection for the prepared sensors were 2.5 × 10−6, 2.2 × 10−6, and 2.7 × 10−6 mol L−1. The sensors showed high selectivity and sensitivity for gemcitabine. Validation of the sensors was carried out in accordance with the requirements established by the IUPAC, while being inexpensive and easy to use in drug formulation. A statistical analysis of the methods in comparison with the official method showed that there was no significant difference in accuracy or precision between them. It was shown that the new sensors could selectively and accurately find gemcitabine hydrochloride in bulk powder, pharmaceutical formulations, and quality control tests. The ionophore-based sensor shows several advantages over conventional PVC membrane sensor sensors regrading the lower limit of detection, and higher selectivity towards the target ion