scholarly journals Interactive Effects of Drought and Saline Aerosol Stress on Morphological and Physiological Characteristics of Two Ornamental Shrub Species

Horticulturae ◽  
2021 ◽  
Vol 7 (12) ◽  
pp. 517
Author(s):  
Stefania Toscano ◽  
Antonio Ferrante ◽  
Daniela Romano ◽  
Alessandro Tribulato
Keyword(s):  
Sea Water ◽  
Net Photosynthesis ◽  
Interactive Effects ◽  
Total Biomass ◽  
Experimental Conditions ◽  
Relative Water ◽  
Effects Of Drought ◽  
Four Levels ◽  
Almost All ◽  
Ornamental Shrubs

Effects of drought and aerosol stresses were studied in a factorial experiment based on a Randomized Complete Design with triplicates on two ornamental shrubs. Treatments consisted of four levels of water container (40%, 30%, 20%, and 10% of water volumetric content of the substrate) and, after 30 days from experiment onset, three aerosol treatments (distilled water and 50% and 100% salt sea water concentrations). The trial was contextually replicated on two species: Callistemon citrinus (Curtis) Skeels and Viburnum tinus L. ‘Lucidum’. In both species, increasing drought stress negatively affected dry biomass, leaf area, net photosynthesis, chlorophyll a fluorescence, and relative water content. The added saline aerosol stress induced a further physiological water deficit in plants of both species, with more emphasis on Callistemon. The interaction between the two stress conditions was found to be additive for almost all the physiological parameters, resulting in enhanced damage on plants under stress combination. Total biomass, for effect of combined stresses, ranged from 120.1 to 86.4 g plant−1 in Callistemon and from 122.3 to 94.6 g plant−1 in Viburnum. The net photosynthesis in Callistemon declined by the 70% after 30 days in WC 10% and by the 45% and 53% in WC 20% and WC 10% respectively after 60 days. In Viburnum plants, since the first measurement (7 days), a decrease of net photosynthesis was observed for the more stressed treatments (WC 20% and WC 10%), by 57%. The overall data suggested that Viburnum was more tolerant compared the Callistemon under the experimental conditions studied.

Modeling COVID-19 Growing Trends to Reveal the Differences in the Effectiveness of Non-Pharmaceutical Interventions among Countries in the World (Preprint)

2020 ◽  
Author(s):  
You Chen ◽  
Yubo Feng ◽  
Chao Yan ◽  
Xinmeng Zhang ◽  
Cheng Gao
Keyword(s):  
Secondary Analysis ◽  
Reproduction Rate ◽  
Cumulative Number ◽  
Linear Regression Models ◽  
Growth Data ◽  
Dynamic Changes ◽  
The World ◽  
Four Levels ◽  
Almost All ◽  
Pharmaceutical Interventions

BACKGROUND Adopting non-pharmaceutical interventions (NPIs) can affect COVID-19 growing trends, decrease the number of infected cases, and thus reduce mortality and healthcare demand. Almost all countries in the world have adopted non-pharmaceutical interventions (NPIs) to control the spread rate of COVID-19; however, it is unclear what are differences in the effectiveness of NPIs among these countries. OBJECTIVE We hypothesize that COVID-19 case growth data reveals the efficacy of NPIs. In this study, we conduct a secondary analysis of COVID-19 case growth data to compare the differences in the effectiveness of NPIs among 16 representative countries in the world. METHODS This study leverages publicly available data to learn patterns of dynamic changes in the reproduction rate for sixteen countries covering Asia, Europe, North America, South America, Australia, and Africa. Furthermore, we model the relationships between the cumulative number of cases and the dynamic reproduction rate to characterize the effectiveness of the NPIs. We learn four levels of NPIs according to their effects in the control of COVID-19 growth and categorize the 16 countries into the corresponding groups. RESULTS The dynamic changes of the reproduction rate are learned via linear regression models for all of the studied countries, with the average adjusted R-squared at 0.96 and the 95% confidence interval as [0.94 0.98]. China, South Korea, Argentina, and Australia are at the first level of NPIs, which are the most effective. Japan and Egypt are at the second level of NPIs, and Italy, Germany, France, Netherlands, and Spain, are at the third level. The US and UK have the most inefficient NPIs, and they are at the fourth level of NPIs. CONCLUSIONS COVID-19 case growth data provides evidence to demonstrate the effectiveness of the NPIs. Understanding the differences in the efficacy of the NPIs among countries in the world can give guidance for emergent public health events. CLINICALTRIAL NA

scholarly journals Licorice (Glycyrrhiza glabra)—Growth and Phytochemical Compound Secretion in Degraded Lands under Drought Stress

2021 ◽  
Vol 13 (5) ◽  
pp. 2923
Author(s):  
Botir Khaitov ◽  
Munisa Urmonova ◽  
Aziz Karimov ◽  
Botirjon Sulaymonov ◽  
Kholik Allanov ◽  
...  
Keyword(s):  
Drought Stress ◽  
Water Deficit ◽  
Background Field ◽  
Field Trials ◽  
Glycyrrhiza Glabra ◽  
Agricultural System ◽  
Positive Effects ◽  
Relative Water ◽  
Moderate Drought ◽  
Four Levels

Water deficiency restricts plant productivity, while excessive soil moisture may also have an adverse impact. In light of this background, field trials were conducted in secondary saline soil (EC 6.5 dS m−1) at the experimental station of Tashkent State Agrarian University (TSAU), Uzbekistan to determine drought tolerance of licorice (Glycyrrhiza glabra) by exposure to four levels of water deficit, namely control (70–80%), moderate (50–60%), strong (30–40%) and intense (10–20%) relative water content (WC) in the soil. The moderate drought stress exhibited positive effects on the morphological and physiological parameters of licorice, and was considered to be the most suitable water regime for licorice cultivation. Plant growth under the 50–60% WC treatment was slightly higher as compared to 70–80% WC treatment, exhibiting weak water deficit promotes licorice growth, root yield and secondary metabolite production. In particular, secondary metabolites i.e., ash, glycyrrhizic acid, extractive compounds and flavonoids, tended to increase under moderate water deficit, however further drought intensification brought a sharp decline of these values. These results contribute to the development of licorice cultivation technologies in arid regions and the most important consideration is the restoration of ecological and economical functions of the dryland agricultural system.

scholarly journals Interactive Effects of Nitrogen and Sulfur Nutrition on Growth, Development, and Physiology of Brassica carinata A. Braun and Brassica napus L.

2021 ◽  
Vol 13 (13) ◽  
pp. 7355
Author(s):  
Shivendra Kumar ◽  
Ramdeo Seepaul ◽  
Ian M. Small ◽  
Sheeja George ◽  
George Kelly O’Brien ◽  
...  
Keyword(s):  
Electron Transport ◽  
Leaf Area ◽  
Photosynthetic Pigments ◽  
Net Photosynthesis ◽  
Brassica Carinata ◽  
Internode Length ◽  
Erucic Acid Content ◽  
Total Biomass ◽  
Node Number ◽  
S 100

Brassica carinata (carinata) has emerged as a potential biofuel source due to its high erucic acid content, making it desirable for various industrial applications. Nitrogen (N) and sulfur (S) are required as primary sources of nutrition for growth and development in different oilseed crops and their utilization is interdependent. The purpose of the study was to analyze the interactive effect of N and S nutrition on the growth and other physiological activities of carinata and B. napus (napus). Four treatments, i.e., optimum NS (+N+S, 100% N and 100% S); N limited (−N+S, 0% N, 100% S); S limited (+N−S, 100% N, 0% S), and NS limited (−N−S, 0% N and 0% S) of N and S in full-strength Hoagland solution were imposed in the current study. Effect of different NS treatments was observed on vegetative traits such as number of primary and secondary branches, total leaf area, total biomass production and allocation, and physiological traits such as production of photosynthetic pigments, net photosynthesis, electron transport, and other aspects for both carinata and napus. The traits of stem elongation, number of nodes, node addition rate, internode length, number of primary and secondary branches were 60%, 36%, 50%, 35%, 56%, and 83% lower, respectively, in napus in comparison to carinata. Different NS treatments also positively influenced the production of photosynthetic pigments such as chlorophyll (Chl) a and b and carotenoids in carinata and napus. The concentration of Chla was 11% higher in napus in comparison to carinata. The rate of net photosynthesis, electron transport, and fluorescence was 12%, 8%, and 5% higher based on overall value, respectively, in napus compared to carinata. On the other hand, the overall value for stomatal conductance decreased by 5% in napus when compared to carinata. Different growth-related traits such as vegetative (plant height, node number, internode length, leaf area, number of primary and secondary branches), reproductive (pod number, pod length, seeds per pod), and photosynthetic capacity in oilseed brassicas are correlated with the final seed and oil yield and chemical composition which are of economic importance for the adoption of the crop. Thus, the analysis of these traits will help to determine the effect of NS interaction on crop productivity of carinata and napus.

Mercury in the Marine Environment: Concentration in Sea Water and in a Pelagic Food Chain

1973 ◽  
Vol 30 (2) ◽  
pp. 293-295 ◽  
Author(s):  
P. M. Williams ◽  
H. V. Weiss
Keyword(s):  
Biological Activity ◽  
Bottom Sediment ◽  
Food Chain ◽  
Mercury Concentration ◽  
Vertical Profile ◽  
Sea Water ◽  
Mercury Content ◽  
Trophic Levels ◽  
Single Station ◽  
Almost All

Mercury in seawater, in a pelagic food chain, and in bottom sediment was determined at a single station 430 km southeast of San Diego, California. The concentration of mercury in zooplankton slightly increased with depth of collection. The mercury content in almost all of the higher trophic levels of organisms collected at greater depths was indistinguishable from the concentration of mercury in zooplankton at these depths. Mercury concentration in the seawater column was essentially constant below 100 m and significantly higher at the surface. This vertical profile of mercury content is not ascribable to biological activity.

Effects of CO2 enrichment and nutrition on growth, photosynthesis, and nutrient concentration of Alaskan tundra plant species

1986 ◽  
Vol 64 (12) ◽  
pp. 2993-2998 ◽  
Author(s):  
Steven F. Oberbauer ◽  
Nasser Sionit ◽  
Steven J. Hastings ◽  
Walter C. Oechel
Keyword(s):  
Plant Biomass ◽  
Co2 Enrichment ◽  
Nutrient Content ◽  
Interactive Effects ◽  
Photon Flux ◽  
Nutrient Concentrations ◽  
Total Biomass ◽  
Ledum Palustre ◽  
Carbon Dioxide Concentrations ◽  
Alaskan Tundra

Three Alaskan tundra species, Carex bigelowii Torr., Betula nana L., and Ledum palustre L., were grown in controlled-environment chambers at two nutrition levels with two concentrations of atmospheric CO2 to assess the interactive effects of these factors on growth, photosynthesis, and tissue nutrient content. Carbon dioxide concentrations were maintained at 350 and 675 μL L−1 under photosynthetic photon flux densities of 450 μmol m−2 s−1 and temperatures of 20:15 °C (light:dark). Nutrient treatments were obtained by watering daily with 1/60- or 1/8- strength Hoagland's solution. Leaf, root, and total biomass were strongly enhanced by nutrient enrichment regardless of the CO2 concentration. In contrast, enriched atmospheric CO2 did not significantly affect plant biomass and there was no interaction between nutrition and CO2 concentration during growth. Leaf photosynthesis was increased by better nutrition in two species but was unchanged by CO2 enrichment during growth in all three species. The effects of nutrient addition and CO2 enrichment on tissue nutrient concentrations were complex and differed among the three species. The data suggest that CO2 enrichment with or without nutrient limitation has little effect on the biomass production of these three tundra species.

scholarly journals Dissociation, unfolding and refolding trials of pig kidney 3,4-dihydroxyphenylalanine (dopa) decarboxylase

1993 ◽  
Vol 295 (2) ◽  
pp. 493-500 ◽  
Author(s):  
P Dominici ◽  
P S Moore ◽  
C Borri Voltattorni
Keyword(s):  
Conformational Changes ◽  
Dopa Decarboxylase ◽  
Experimental Conditions ◽  
High Tendency ◽  
Denatured Protein ◽  
Pig Kidney ◽  
Plausible Model ◽  
Spectroscopic Characteristics ◽  
Equilibrium Transition ◽  
Almost All

The effect of guanidinium chloride (GuCl) on enzyme activity, hydrodynamic volume, circular dichroism, and fluorescence of 3,4-dihydroxyphenylalanine (Dopa) decarboxylase from pig kidney (pkDDC) was studied under equilibrium conditions. Unfolding proceeds in at least three stages. The first transition, occurring between 0 and 1 M GuCl, gives rise to a dimeric inactive species which has lost pyridoxal 5′-phosphate (PLP), and has a high tendency to aggregate, but retains almost all of the native spectroscopic characteristics. The second equilibrium transition, between 1 and 2.2 M GuCl, involves dimer dissociation, with some loss of tertiary and secondary structure. Additionally, gross conformational changes at or near the PLP microenvironment were detected by fluorescence of NaBH4-reduced enzyme. The third step, presumably representing complete unfolding of pkDDC, appears to be complete at 4.5 M GuCl, as indicated by the lack of further substantial changes in any of the signals being studied. Attempts at refolding resulted in the findings that: (1) partial reactivation is observed only starting from enzyme denatured at concentrations below 1.5 M GuCl, and (2) starting from completely denatured protein, the refolding process is apparently reversible down to concentrations of approx. 2 M GuCl. Taken together, this would seem to indicate that the monomer-dimer transition is impaired under the experimental conditions tested. A plausible model is presented for the unfolding/refolding of pkDDC.

Degradation of Amaranth azo dye in water by heterogeneous photo-Fenton process using FeWO4 catalyst prepared by microwave irradiation

2015 ◽  
Vol 73 (1) ◽  
pp. 88-94 ◽  
Author(s):  
Eric da Cruz Severo ◽  
Chayene Gonçalves Anchieta ◽  
Vitória Segabinazzi Foletto ◽  
Raquel Cristine Kuhn ◽  
Gabriela Carvalho Collazzo ◽  
...  
Keyword(s):  
Azo Dye ◽  
Fenton Reaction ◽  
Catalytic Properties ◽  
Interactive Effects ◽  
Fenton Process ◽  
Operational Parameters ◽  
Treatment Efficiency ◽  
Experimental Conditions ◽  
Decolorization Efficiency ◽  
Central Composite

FeWO4 particles were synthesized by a simple, rapid and facile microwave technique and their catalytic properties in heterogeneous photo-Fenton reaction were evaluated. This material was employed in the degradation of Amaranth azo dye. Individual and interactive effects of operational parameters such as pH, dye concentration and H2O2 dosage on the decolorization efficiency of Amaranth dye were evaluated by 23 central composite design. According to characterization techniques, a porous material and a well-crystallized phase of FeWO4 oxide were obtained. Regarding the photo-Fenton reaction assays, up to 97% color and 58% organic carbon removal were achieved in the best experimental conditions. In addition, the photo-Fenton process maintained treatment efficiency over five catalyst reuse cycles to indicate the durability of the FeWO4 catalyst. In summary, the results reveal that the synthesized FeWO4 material is a promising catalyst for wastewater treatment by heterogeneous photo-Fenton process.

scholarly journals Effect of Sulphur and GA3 on the Growth and Yield of Onion

2013 ◽  
Vol 21 (1-2) ◽  
pp. 57-63 ◽  
Author(s):  
MHA Rashid
Keyword(s):  
Dry Matter ◽  
Matter Content ◽  
Growth And Yield ◽  
Control Treatment ◽  
Dry Matter Content ◽  
Number Of Leaves ◽  
Four Levels ◽  
Experimental Findings ◽  
Almost All ◽  
Bulb Yield

An experiment was conducted at the Horticulture Farm of the Bangladesh Agricultural University, Mymensingh to evaluate the effects of sulphur and GA3 on the growth and yield performance of onion cv. BARI Peaj-1. The experiment included four levels of sulphur viz., 0 (control), 15, 30 and 45 kg/ha and four concentrations of GA3 viz., 0 (control), 50, 75, 100 ppm. The experimental findings revealed that sulphur and GA3 had significant influence on plant height, number of leaves per plant, bulb diameter and length, individual bulb weight, splitted and rotten bulb, bulb dry matter content and bulb yield. The highest bulb yield (13.85 t/ha) was recorded from 30 kg S/ha, while the lowest bulb yield (11.20 t/ha) was obtained from control. Most of the parameters showed increasing trend with the higher concentration of GA3. Application of GA3 @ 100 ppm gave the maximum bulb yield (15.23 t/ha), while the minimum value (10.10 t/ha) was observed from control. Almost all the parameters were significantly influenced by combined treatments of sulphur and GA3 except bulb length of onion. The maximum bulb dry matter content (13.50%) and bulb yield (17.10 t/ha) were produced from the application of sulphur @ 30 kg/ha with 100ppm GA3, while the minimum bulb dry matter content (9.23%) and bulb yield (9.33 t/ha) were recorded from control treatment of sulphur with GA3.DOI: http://dx.doi.org/10.3329/pa.v21i1-2.16749 Progress. Agric. 21(1 & 2): 57 - 63, 2010

scholarly journals Benthic microalgae community response to flooding in a tropical salt flat

2016 ◽  
Vol 76 (3) ◽  
pp. 577-582 ◽  
Author(s):  
L. S. M. Masuda ◽  
A. Enrich-Prast
Keyword(s):  
Sea Water ◽  
Shannon Index ◽  
Community Response ◽  
Microbial Mat ◽  
Total Density ◽  
Experimental Conditions ◽  
Effect Of Water ◽  
Salt Flat ◽  
Field Samples ◽  
Order Of Magnitude

Abstract This research evaluated the effect of flooding on the microphytobenthos community structure in a microbial mat from a tropical salt flat. Field samples were collected during four consecutive days: on the first three days the salt flat was dry, on the fourth day it was flooded by rain. In order to evaluate the community maintained in flood conditions, samples from this area were collected and kept in the laboratory for 10 days with sea water. The results of total abundance of microphytobenthos varied from 4.2 × 108 to 2.9 × 109 organisms L–1, total density increased one order of magnitude under the effect of water for both situations of precipitation in the salt flat and in experimental conditions, an increase due to the high abundance of Microcoleus spp. Shannon index (H’) was higher during the desiccation period. Our data suggest that changes in the abundance of organisms were due to the effect of water. The dominance of the most abundant taxa remained the same under conditions of desiccation and influence of water, and there is probably a consortium of microorganisms in the microbial mat that helps to maintain these dominances.

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