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1.
Sci Prog ; 106(4): 368504231219171, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38113117

RESUMO

The tobacco cutworm (Spodoptera litura) is a widespread pest that inflicts severe damage on various crops, including cotton, tobacco, and vegetables, with a particular preference for solanaceous plants. Traditional control methods often rely heavily on synthetic insecticides, leading to adverse effects on the environment, human health, and the development of insecticide resistance. In light of these challenges, this study explores the potential of nanotechnology as an innovative and sustainable approach to combat this notorious pest. Bioassays were conducted using laboratory-reared 3rd instar S. litura larvae. Eight different plant extracts coated with zinc oxide and silver nitrate nanoparticles were tested, with concentrations in both distilled water and ethanol at 3, 5, and 7 ml. Data were collected at 24, 48, and 72-h intervals. The results revealed that the highest larval mortality, reaching 98%, was observed in the group treated with silver nitrate nanoparticles derived from Cymbopogon citratus. In comparison, the group treated with zinc oxide nanoparticles dissolved in ethanol exhibited a larval mortality rate of 90%. Ethanol is a polar solvent that is widely used in the synthesis of nanocomposites. It is capable of forming strong hydrogen bonds with oxygen atoms, making it a good dispersant for zinc oxide nanoparticles. Additionally, ethanol has a low boiling point and a non-toxic nature, which makes it a safe and effective option for the dispersion of nanoparticles. Notably, the study concluded that silver nanoparticles combined with ethanol exhibited prolonged and more potent toxic effects against S. litura when compared to zinc oxide nanoparticles. Overall, this research underscores the potential of nanotechnology as a valuable component of Integrated Pest Management (IPM) strategies. By integrating nanotechnology into pest management practices, we can promote sustainable and environmentally friendly approaches that benefit both farmers and the ecosystem.


Assuntos
Nanopartículas Metálicas , Controle de Pragas , Óxido de Zinco , Animais , Ecossistema , Etanol , Larva , Nanopartículas Metálicas/toxicidade , Nitratos/farmacologia , Extratos Vegetais/farmacologia , Prata/farmacologia , Nitrato de Prata/farmacologia , Spodoptera , Óxido de Zinco/farmacologia
2.
Neotrop Entomol ; 52(4): 772-780, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37195556

RESUMO

Two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is a phytophagous haplodiploid mite and its control is largely based on the use of pesticides. But, the short life cycle and high reproductive rate allow them to develop resistance to many pesticides. To design a strategy for resistance management, a fitness cost study was conducted on different populations of T. urticae, i.e., spiromesifen selected (SPIRO-SEL), unselected (Unsel), and reciprocal crosses. After twelve rounds of selections, T. urticae developed high spiromesifen resistance (71.7-fold) compared to the Unsel strain. Results showed a fitness cost for SPIRO-SEL, Cross1 (Unsel ♀ × SPIRO-SEL ♂), and Cross2 (SPIRO-SEL ♀ × Unsel ♂) with a relative fitness values of 0.63, 0.86, and 0.70, respectively. There was a significant increase in the incubation period, quiescent larvae, and egg to adult male and female developmental period of the SPIRO-SEL compared with Unsel strain. Moreover, resistance to spiromesifen was unstable with a decline in resistance value of - 0.05. The presence of unstable spiromesifen resistance associated with fitness costs suggests that intermittent withdrawal of its usage could potentially preserve its effectiveness for management of T. urticae.


Assuntos
Acaricidas , Praguicidas , Compostos de Espiro , Tetranychidae , Feminino , Masculino , Animais
3.
Nanomaterials (Basel) ; 13(7)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-37049240

RESUMO

Nanoscale surface roughness has conventionally been induced by using complicated approaches; however, the homogeneity of superhydrophobic surface and hazardous pollutants continue to have existing challenges that require a solution. As a prospective solution, a novel bubbled-structured silica nanoparticle (SiO2) decorated electrospun polyurethane (PU) nanofibrous membrane (SiO2@PU-NFs) was prepared through a synchronized electrospinning and electrospraying process. The SiO2@PU-NFs nanofibrous membrane exhibited a nanoscale hierarchical surface roughness, attributed to excellent superhydrophobicity. The SiO2@PU-NFs membrane had an optimized fiber diameter of 394 ± 105 nm and was fabricated with a 25 kV applied voltage, 18% PU concentration, 20 cm spinning distance, and 6% SiO2 nanoparticles. The resulting membrane exhibited a water contact angle of 155.23°. Moreover, the developed membrane attributed excellent mechanical properties (14.22 MPa tensile modulus, 134.5% elongation, and 57.12 kPa hydrostatic pressure). The composite nanofibrous membrane also offered good breathability characteristics (with an air permeability of 70.63 mm/s and a water vapor permeability of 4167 g/m2/day). In addition, the proposed composite nanofibrous membrane showed a significant water/oil separation efficiency of 99.98, 99.97, and 99.98% against the water/xylene, water/n-hexane, and water/toluene mixers. When exposed to severe mechanical stresses and chemicals, the composite nanofibrous membrane sustained its superhydrophobic quality (WCA greater than 155.23°) up to 50 abrasion, bending, and stretching cycles. Consequently, this composite structure could be a good alternative for various functional applications.

4.
Heliyon ; 9(1): e12883, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36691543

RESUMO

Given the carcinogenic properties of formaldehyde-based chemicals, an alternative method for resin-finishing cotton textiles is urgently needed. Therefore, the primary objective of this study is to introduce a sustainable resin-finishing process for cotton fabric via an industrial procedure. For this purpose, Bluesign® approved a formaldehyde-free Knittex RCT® resin was used, and the process parameters were designed and optimized according to the Taguchi L27 method. XRD analysis confirmed the crosslinking formation between resin and neighboring molecules of cotton fabric, as no change in the cellulose crystallization phase. Several machine learning models were built in a sequence to predict the crease recovery angle (CRA), tearing strength (TE) and whiteness index (WI). Assessment of modelling was evaluated through the use of various metrics such as root mean square error (RMSE), mean absolute error (MAE), and the coefficient of determination (R2). Results were compared to those from other regression models, such as principal component regression (PCR), partial least squares regression (PLSR), and fuzzy modelling. Based on the results of our research, the LSSVR model predicted the CRA, TE, and WI with substantially more accuracy than other models, as shown by the fact that its RMSE and MAE values were significantly lower. In addition, it offered the greatest possible R2 values, reaching up to 0.9627.

5.
Environ Sci Pollut Res Int ; 30(4): 9207-9242, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36459315

RESUMO

The rapid growth of population and industrialization have intensified the problem of water pollution globally. To meet the challenge of industrialization, the use of synthetic dyes in the textile industry, dyeing and printing industry, tannery and paint industry, paper and pulp industry, cosmetic and food industry, dye manufacturing industry, and pharmaceutical industry has increased exponentially. Among these industries, the textile industry is prominent for the water pollution due to the hefty consumption of water and discharge of coloring materials in the effluent. The discharge of this effluent into the aquatic reservoir affects its biochemical oxygen demand (BOD), chemical oxygen demand (COD), total dissolved solids (TDS), total suspended solids (TSS), and pH. The release of the effluents without any remedial treatment will generate a gigantic peril to the aquatic ecosystem and human health. The ecological-friendly treatment of the dye-containing wastewater to minimize the detrimental effect on human health and the environment is the need of the hour. The purpose of this review is to evaluate the catastrophic effects of textile dyes on human health and the environment. This review provides a comprehensive insight into the dyes and chemicals used in the textile industry, focusing on the typical treatment processes for their removal from industrial wastewaters, including chemical, biological, physical, and hybrid techniques.


Assuntos
Poluentes Químicos da Água , Humanos , Poluentes Químicos da Água/análise , Ecossistema , Águas Residuárias , Corantes/química , Têxteis , Indústria Têxtil , Resíduos Industriais/análise
6.
Inf Technol Manag ; : 1-22, 2022 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-36267115

RESUMO

Despite researchers having averred that big data analytics (BDA) transforms firms' ways of doing business, knowledge about operationalizing these technologies in organizations to achieve strategic objectives is lacking. Moreover, organizations' great appetite for big data and limited empirical proof of whether BDA impacts organizations' transformational capacity poses a need for further empirical investigation. Therefore, this study explores the association between big data analytics management capabilities (BDAMC) and innovation performance via dynamic capabilities (DC), by applying the PLS-SEM technique to analyzing the feedback of 149 firms. Consequently, we ground our arguments on dynamic capability and social capital theory rather than a resource-based view that does not provide suitable explanations for the deployment of resources to adapt to change. Accordingly, we advance this research stream by finding that BDAMC significantly enhances innovation performance through DC. We also extend the literature by disclosing how BDAMC strengthens DC via strategic alignment and social capital.

7.
Saudi J Biol Sci ; 28(10): 5720-5727, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34588883

RESUMO

Taxonomic identification and classifications of insect pest genera Chrysodeixis and Ctenoplusia of the subfamily Plusiinae is very compulsory due to their phytophagous nature and potential to damage the cash as well as cereal crops. Taxonomy plays a key role in proper not only in identification and classification of the pest but also in designing a successful managing strategy. In current study, specimens of Chrysodeixis and Ctenoplusia genera were collected from different geographical areas of south Punjab, Pakistan and their diagnostic features were examined following taxanomic keys. The data of temperature, relative humidity and rainfall were also recorded during the study period. Genitalia was extracted by dissecting of the abdomen and inspected under Stereo microscope. The results revealed two new species, Chryodeixis maxus and Ctenoplusia oleraceaus, from south Punjab region in addition to previously reported species: Chrysodeixis furihatai. Suitable management of the voracious insect pest at appropriate time may help in sustaining the agriculture in Pakistan.

8.
J Environ Manage ; 298: 113466, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34371223

RESUMO

Novel highly porous nanoparticle materials are increasingly being applied in adsorption processes, but they need to be supported by robust matrixes to maintain their functionality. We present a study of hosting graphene oxide (GO) particles on polyether block amide (PEBA) melt electrospun fibers and applying such composite matrix to the adsorption of the cationic dye (crystal violet) from water. Various amounts of GO (from 0.5 to 2.0%) were mixed into pure PEBA and electrospun by melt electrospinning obtaining micro fibrous matrixes. These were characterized for morphology (SEM), chemical composition (FTIR), crystallinity (XRD), and wetting behavior (WCA). The increasing amount of GO adversely affected fiber diameter (reduced from 13.18 to 4.38 µm), while the hydrophilic properties (Water contact angle decrease from 109 to 76°) and overall dye adsorption was increased. Efficient adsorption has been demonstrated, reaching approximately 100 % removal efficiency using a 2% GO composite matrix at a dose of 40 mg/l and pH of 10. Further increase of GO concentration in polymer is not feasible due to instability in the electrospinning process.


Assuntos
Grafite , Poluentes Químicos da Água , Adsorção , Amidas , Elastômeros , Águas Residuárias
9.
Saudi J Biol Sci ; 27(7): 1818-1823, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32565701

RESUMO

Drought stress constricts crop production in the world. Increasing human population and predicted temperature increase owing to global warming will lead ruthless problems for agricultural production in near future. Hence, use of high yielding genotypes having drought tolerance and scrutinize of drought sensitive local cultivars for making them tolerant may be the proficient approaches to cope its detrimental outcomes. The current study was executed during 20015-2016 and 2016-2017 in field using randomized complete block design under factorial arrangements on 50 wheat genotypes for exploring their sensitivity and tolerance against drought. Some of the attributes of grain yield and drought tolerance indices were recorded. Grain yield showed negative correlations with tolerance index (TOL), drought index (DI) and stress susceptibility index (SSI) while positive correlation with mean productivity (MP) and geometric mean productivity (GMP) under drought condition. These findings depicted that tolerant genotypes could be chosen by high MP and GMP values and low SSI and TOL values. Based on the results, genotypes GA-02, Faisalabad-83, 9444, Sehar-06, Pirsabak-04 and Kohistan-97 were more tolerant and recognized as suitable for both normal and drought conditions. Genotypes of Chenab-00, Kohsar-95, Parwaz-94 and Kohenoor-83 confirmed more sensitive due to high grain yield loss under drought stress.

10.
Saudi J Biol Sci ; 27(5): 1375-1379, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32346348

RESUMO

Species belonging to genus, Thysanoplusia Fabricius of the subfamily Plusiinae which are polyphagous in nature and pest of vegetables, foods, legumes, fodder, fruits, ornamental plants and cotton crops. Samples were collected from different localities of district Bahawalpur. For collection, comprehensive and comparative surveys were carried out during 2017-18 on taxonomic account of species of the genus Thysanoplusia Fabricius and resulted identified one species Thysanoplusia orichalcea (Fabricius) first time from Pakistan. Morphological characters viz., vertex, frons, labial palpi, antennae, compound eyes, ocelli, proboscis, wing venation, male and female genital characteristics were used for the identification and classification. Dichotomous keys and photographs are also provided. There is hardly any substantial research work on taxonomic studies of subfamily Plusiinae Pakistan. So to fill this gap the present proposal was designed to study the diversity of Noctuid moths from Pakistan and very fruitful results have been obtained.

11.
Polymers (Basel) ; 12(4)2020 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-32260569

RESUMO

Polyether block amide (PEBA) nanocomposite membranes, including Graphene (GA)/PEBA membranes are considered to be a promising emerging technology for removing CO2 from natural gas and biogas. However, poor dispersion of GA in the produced membranes at industrial scale still forms the main barrier to commercialize. Within this frame, this research aims to develop a new industrial approach to produce GA/PEBA granules that could be used as a feedstock material for mass production of GA/PEBA membranes. The developed approach consists of three sequential phases. The first stage was concentrated on production of GA/PEBA granules using extrusion process (at 170-210 °C, depending on GA concentration) in the presence of Paraffin Liquid (PL) as an adhesive layer (between GA and PEBA) and assisted melting of PEBA. The second phase was devoted to production of GA/PEBA membranes using a solution casting method. The last phase was focused on evaluation of CO2/CH4 selectivity of the fabricated membranes at low and high temperatures (25 and 55 °C) at a constant feeding pressure (2 bar) using a test rig built especially for that purpose. The granules and membranes were prepared with different concentrations of GA in the range 0.05 to 0.5 wt.% and constant amount of PL (2 wt.%). Also, the morphology, physical, chemical, thermal, and mechanical behaviors of the synthesized membranes were analyzed with the help of SEM, TEM, XRD, FTIR, TGA-DTG, and universal testing machine. The results showed that incorporation of GA with PEBA using the developed approach resulted in significant improvements in dispersion, thermal, and mechanical properties (higher elasticity increased by ~10%). Also, ideal CO2/CH4 selectivity was improved by 29% at 25 °C and 32% at 55 °C.

12.
Saudi J Biol Sci ; 27(1): 1-5, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31889809

RESUMO

Plutella xylostella L. (Lepidoptera: Plutellidae) is an important pest causing significant losses to vegetables worldwide. Insecticides resistance in P. xylostella is a serious issue for scientists since last 30 years. However, deltamethrin and Bt Cry1Ac are commonly used insecticides against P. xylostella but studies involving development of resistance in P. xylostella against these two insecticides at different temperatures are lacking. The current study was aimed to find out the toxicity of deltamethrin and Bt Cry1Ac, and resistance development in P. xylostella. Results showed that the positive correlation between the temperature and toxicities of deltamethrin and Bt Cry1Ac. The results indicated -0.051, -0.049, -0.047, and -0.046 folds of deltamethrin resistance at 15 °C, 20 °C, 25 °C, and 30 °C temperatures, respectively from 1st to 12th generations. The toxicity of Bt Cry1Ac after 24 h was 2.2 and 4.8 folds on 1st generation at 20 °C and 25 °C temperatures, respectively compared to the toxicity recorded at 15 °C (non-overlapping of 95% confidence limits). Based on the results of this study, it is concluded that the temperature has a positive correlation with the toxicity of deltamethrin and Bt Cry1Ac against the larvae of P. xylostella. This study suggests that deltamethrin and Bt Cry1Ac can be included in the management program of P. xylostella on many vegetable crops. The baseline susceptibility data might be helpful to understand the resistance mechanisms in P. xylostella.

13.
Saudi J Biol Sci ; 26(7): 1548-1552, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31762624

RESUMO

Indian siris, Albizia lebbeck (L.) Benth. (Fabaceae: Mimosoideae) has significant importance to human beings for its multipurpose use. Insects play a crucial role in the pollination biology of flowering plants. In the current study, we studied the pollination biology of A. lebbeck with special reference to insect floral visitors. The effectiveness of floral visitors was investigated in term of visitation frequency, visitation rate and pollen load during 2012 and 2013. In the second experiment, effect of pollinators on yield of A. lebbeck was studied in open and cage pollination experiments. Floral visitor fauna of A. lebbeck included eight-bees, two wasps, two flies, and two butterflies species. Among them, Apis dorsata, Apis florea, Amegilla cingulata, and Nomia oxybeloides had maximum abundance ranging from 349-492, 339-428, 291-342 and 235-255 numbers of individuals, respectively during two flowering seasons. A. dorsata had the highest visitation frequency (6.44 ±â€¯0.49-8.78 ±â€¯0.48 visits/flower/5min) followed by Amegilla cingulata (6.03 ±â€¯0.43-7.99 ±â€¯0.33 visits/flower/5min) and A. florea (3.61 ±â€¯0.31-4.44 ±â€¯0.18 visits/flower/5min). A. dorsata, N. oxybeloides, and Amegilla cingulata had the highest visitation rates (18.904 ±â€¯1.53-11.43 ±â€¯1.17 flower visited/min) and pollen load (15333 ±â€¯336.22-19243 ±â€¯648.45 pollen grains). The open pollinated flowers had significantly higher capsule weight (4.97 ±â€¯0.21 g), seed weight (1.04 ±â€¯0.05 g), seed numbers per pod (9.80 ±â€¯0.34) and seed germination percentage (84.0 ±â€¯1.78%) as compared to caged flowers. The results suggested bees especially A. dorsata, N. oxybeloides and Amegilla cingulata could be effective pollinators of A. lebbeck.

14.
Saudi J Biol Sci ; 26(7): 1661-1667, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31762641

RESUMO

Different temperature zones have significant impact on the population dynamics of Plutella xylostella. Effective management of P. xylostella requires the knowledge of temperature tolerance by different life stages. In the current study, fitness parameters of diamondback moth were reported by using age-stage, two-sex life table traits at four constant temperatures (15, 20, 25 and 30 °C). The life cycle of P. xylostella was significantly longer at 15 °C. The 20 °C level of temperature was found optimal for fecundity, gross reproductive rate (51.74 offspring) and net reproductive rate (44.35 offspring per individual). The adult pre-oviposition period was statistically at par at all four level of temperatures. However, the survival was maximum at 20 °C as compared to other three temperature ranges. Based on the current study, it was concluded that temperature has a great role in population build-up of P. xylostella and effective management tactics should be applied to prevent significant damage to cabbage and other cruciferous crops when the temperature in the field is near 20 °C.

15.
Environ Sci Pollut Res Int ; 25(17): 17033-17037, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29633191

RESUMO

Red cotton bug, Dysdercus koenigii (Hemiptera: Pyrrhocoridae), has become the major insect pest of various crops, including cotton, and thereby reducing the yield qualitatively and quantitatively and synthetic insecticides belonging to different groups are the major control agents for such insect pests. A laboratory experiment was carried out to evaluate the effect of different conventional insecticides, i.e., imidacloprid, deltamethrin, lambda cyhalothrin, gamma cyhalothrin and cyfluthirn on haemocytes of D. koenigii. The individuals were exposed to insecticides separately and data was recorded after 30 and 60 min of the exposure. The findings of current study depicted chlorpyrifos to be more effective and significant alterations in total haemocyte counts and differential haemocyte counts were observed in the cyfluthirn treated D. koenigii. In addition to this, cell structure was also disrupted as an immune response. Similar studies would also be helpful to understand the defence mechanisms of insects against the xenobiotics which will help to device efficient management tools for D. koenigii.


Assuntos
Clorpirifos/farmacologia , Hemípteros/efeitos dos fármacos , Heterópteros/efeitos dos fármacos , Inseticidas/farmacologia , Neonicotinoides/química , Nitrilas/química , Nitrocompostos/química , Piretrinas/química , Animais
16.
Materials (Basel) ; 11(3)2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29543724

RESUMO

In this study, the influence and optimization of the factors of a non-formaldehyde resin finishing process on cotton fabric using a Taguchi-based grey relational analysis were experimentally investigated. An L27 orthogonal array was selected for five parameters and three levels by applying Taguchi's design of experiments. The Taguchi technique was coupled with a grey relational analysis to obtain a grey relational grade for evaluating multiple responses, i.e., crease recovery angle (CRA), tearing strength (TE), and whiteness index (WI). The optimum parameters (values) for resin finishing were the resin concentration (80 g·L-1), the polyethylene softener (40 g·L-1), the catalyst (25 g·L-1), the curing temperature (140 °C), and the curing time (2 min). The goodness-of-fit of the data was validated by an analysis of variance (ANOVA). The optimized sample was characterized by Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and scanning electron microscope (SEM) to better understand the structural details of the resin finishing process. The results showed an improved thermal stability and confirmed the presence of well deposited of resin on the optimized fabric surface.

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