Silver Leaf Research Articles

Barrier films or dressings for the prevention of acute radiation dermatitis in breast cancer: a systematic review and network meta-analysis.

Barrier films or dressings were reported to be effective in preventing radiation dermatitis (RD) in breast cancer patients, but their comparative efficacy is unknown. A systematic literature search was performed on Embase, MEDLINE and Cochrane CENTRAL Registry of Clinical Trials from inception to October 20, 2023. Randomised controlled trials (RCTs) comparing barrier films or dressings to the standard of care (SOC) or other interventions were included. We estimated summary odds ratios and mean differences using network meta-analysis with random effects. This study was registered with PROSPERO (ID: CRD42023475021). Fourteen RCTs met inclusion criteria. Six interventions were analysed: 3M™ Moisturizing Double Barrier Cream (MDBC), 3M™ No Sting Barrier Film (BF), Hydrofilm® (HF), Mepitel® Film (MF), Silver Leaf Nylon Dressing and StrataXRT®. HF, MF and StrataXRT® reduced the incidence of moist desquamation compared to SOC (HF: OR = 0.08; p = 0.02; MF: OR = 0.31 p < 0.01; StrataXRT®: OR = 0.22, p = 0.04). The ranking of agents from most to least effective in preventing moist desquamation according to P-scores was HF (92.5%), MF (78.5%), StrataXRT® (70.1%), BF (46.4%), Silver Leaf Nylon Dressing (24.9%), MDBC (22.9%) and SOC (14.7%). Only four RCTs on HF and MF included patient-reported outcome (PRO) assessments that allowed pooling for analysis. HF and MF were more effective in reducing pain, itchiness and burning sensation compared to SOC (p < 0.01 for all symptoms). HF and MF were effective in preventing RD in breast cancer. Future RCTs should compare these interventions to effective cream preparations, such as topical corticosteroids.

Anatomy of the Painting: The Study of the Serbian Orthodox Icon from the Turn of the Seventeenth to the Eighteenth Century

The paper presents the results of the multi-analytical study of the painting on a panel from the icon collection of the Gallery of Matica srpska museum in Novi Sad, Serbia. It is part of the research aiming to set the methodology for the museum’s database on artistic materials and techniques present in the collection. Computer tomography (CT) scanning was used to understand the structure of the wooden panel support. Ultraviolet (UV) and infrared (IC) imaging, as well as visible (VIS) macro photography, were used to study the paint layer, both the original part and restoration treatments, as well as the coat of varnish. Energy dispersive X-ray fluorescence (EDXRF) and Fourier-transform infrared (FTIR) spectroscopy revealed the pigments, binders, and metal leaf, defining the artistic technique. Optical microscopy (OM) and scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS) were used to disclose the stratigraphy and composition of layers in the artwork. The multi-analytical approach confirmed that protein-based binder, gilding, silver leaf, and traditional pigments were used. The data gathered from this research are important for studying the artistic materials and techniques in icon production and defining the methodology setting for the museum collection’s databases as the reference material.

Ornamented stirrup from the elite early Medieval burial at Balyk-Sook (Central Altai)

The article presents an ornamented iron stirrup from a rich and noble early Medieval burial in the Balyk-Sook area in the central part of the Russian Altai. This burial is unique not only for South Siberia, but also for neighbor-ring regions, as within it, with the warrior, four horses and protective armour were found. During the course of restoration work, it was established that the arcs and the plate loop of the stirrup were originally gilded and en-graved with complex floral ornamentation, the stirrup foot was decorated with gold wire inlay in the form of floral curls. This is the first find of such type in Altai. The burial containing the stirrup was radiocarbon dated to the sec-ond half of the 7th — third quarter of the 8th c. The author provides a wide range of similarities among the “status” or “ceremonial” stirrups from funerary and memorial sites of nomadic nobility, including the Kagans from South Siberia, Central Asia, and Eastern and Central Europe, including the such sites of Kagan status as Shoroon Bumbagar in Central Mongolia and Yeleke sazy in Eastern Kazakhstan, Uibat and Tashebinsk Chaatases in the Minusinsk Basin, the Pereshchepinsk hoard and the Voznesenka memorial complex in Eastern Europe, rich Avar burials in Central Europe, and others. Massive and high stirrups with a plate loop were specifically considered during the Medieval period as “status” stirrups, and in some cases they were additionally decorated with orna-mentation. They could be cast in gold or silver, covered with gold or silver leaf, decorated with complex ornamen-tation in various techniques, or decorated with shaped cuts in the stirrup foot. While Avar stirrups, based on Byzan-tine coins in burials, are dated to the late 6th — early 7th c., radiocarbon dating and analogies show that Central Asian stirrups belong to a later period — second half of the 7th — 8th c., and in some cases to the 9th c. Highly ornamented stirrups from the monuments of South Siberia and Central Asia were probably made on order by Chinese masters for the Turkic-speaking nobility, or may have been received as diplomatic gifts from Tang China.

“Hearts of gold” (Cuori d'oro): The case study of the leather corami of Palazzo Chigi in Ariccia

In this work we present the results obtained by different technical analysis in order to perform the characterization of the chromatic richness, the employed materials and the iconographic elements of different fragments of decorated and gilded leather corami coming from the archive of Palazzo Chigi of Ariccia (Rome) and employed, during the 17th century, as wallcoverings. Different microscopic and spectroscopic analyses have been performed by means of Ion Beam Analysis (IBA) and Macro Area X-Ray Fluorescence (MA-XRF) techniques available at the INFN LABEC ion beam laboratory in Florence and the Scanning Electron Microscopy-Energy Dispersive X-ray Analysis (SEM-EDX) of the Superconductivity Laboratory of the ENEA Frascati Research Center. The results aim to provide the scholar information about the manufacturing process and the materials employed for the production of these peculiar artefacts, also in order to plan the best and most appropriate conservation protocol. In particular, thanks to the SEM-EDX analysis it has been possible to characterize the layered structure of the samples and, specifically, the interface between the leather of the substrate, the metal foil of the so called meccatura and between these and the overlying pictorial layer. The IBA and MA-XRF techniques has helped in characterizing the painting palette employed while IBA has allowed to determine the conservation condition of the silver layer with the hypothesis of the incorporation of the silver leaf into the organic compound of the mecca as its main deterioration phenomena. These complementary techniques provide, therefore, a comprehensive understanding of the materials and iconographic elements of these leather-based artefacts, which is essential for their preservation and restoration as well as they contribute to a better understanding of the deterioration processes they incur.

A Recently Identified Barniz Brillante Casket at Bateman’s, the Home of Rudyard Kipling

A casket held at Bateman’s, Rudyard and Caroline Kipling’s home in Sussex—now a National Trust property—was recently recognised as a barniz brillante work. Objects made of barniz brillante, a technique featuring the Indigenous American material called mopa mopa, are relatively rare and have only sparingly been studied using scientific analysis techniques. A collaboration between the National Trust and the Victoria and Albert Museum has produced scientific evidence which will be invaluable in the study and the understanding of this type of object. The scientific analysis of the casket was conducted exclusively in a non-destructive and non-invasive manner, to preserve the integrity of the object which is in very good condition. The Bateman’s casket is characterised by a dark underdrawing, made with a material which is transparent in the infrared region of the electromagnetic spectrum. Most of the areas decorated with silver leaf have tarnished due to the formation of what is likely to be silver chloride. This study represents a significant step towards the comparative scientific study of barniz brillante objects in other collections, which in turn will make it possible to suggest a timeline for their manufacture, and even identify workshops.

Determination of Optimum Level of Seeding Rate of Silver Leaf Desmodim Intercropping with Desho Grass for Dry Matter Yield and Yield-Related Components in Western Ethiopia

Compatible production of forage grasses and legumes through intercropping is one of the best options to achieve higher biomass yield and forage quality for animal production in areas where land and other resources are scarce. This study was conducted in 2017 and 2018 with the aim of evaluating the best-match level of seeding rate of silverleaf desmodium (SLD) intercropped with desho grass (Pennisetum pedicellatum) in a randomized complete block design with three replications. The treatment consists of three levels of seeding rate of SLD (2, 4, and 6 kg ha−1) and one pure plot of each species. The result of this study showed that the intercropping of 6 kg ha−1 SLD with 100% of desho’s recommended plant population (50,000 plants ha−1) produced the highest forage dry matter yield and maximum plant height. The total dry matter yield (TDMY) of the intercrops was also significantly varied for the tested treatments. Accordingly, 6 kg ha−1 of SLD intercropped with 100% recommended seed rate of desho ha−1 gave the highest forage TDMY, which surpasses both the grass and legume yields in monoculture. The total land equivalent ratio (LER), which shows system productivity, was also different among the treatments. About 6 kg ha−1 of SLD intercropped with 100% recommended seed rate of desho also produced the highest LER (1.51). Thus, in Bako and similar agro-climatic conditions, where arable land is heavily covered with food crops, desho grass intercropping with SLD can be used as one of the best strategic options for producing feeds of energy and protein sources simultaneously on the same area of land.

Biological control potentials of Chrysoperla zastrowi sillemi (Neuroptera: Chrysopidae) against Bemisia tabaci (Hemiptera: Aleyrodidae) on polyhouse grown parthenocarpic cucumber in North-Western India

The silver leaf whitefly, Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae), stands out as a highly destructive insect in temperate, tropical, and subtropical regions, inflicting extensive damage to agricultural crops worldwide. Its impact resonates in India, where it has emerged as a formidable pest. Moreover, the excessive use of chemically-derived pesticides has led to the emergence of insect-resistant strains, resulting in environmental pollution and endangering human health. The use of natural enemies is a sustainable and environmentally safe alternative management tactic. The predation potential of green lacewing, Chrysoperla zastrowi sillemi Esben-Peterson (Neuroptera: Chrysopidae) on eggs, nymphs and adults of B. tabaci infesting parthenocarpic cucumber grown under polyhouse has been examined here. On cucumber plants, three releases of 2nd instar C. zastrowi sillemi larvae (at one, two and three larvae/plant) were made at 7 days intervals. The release of three larvae/plant resulted in significantly higher predation rate on whitefly population (58.6% on egg, 61.0% on nymph and 32.3% on adult stage of the whitefly) than two or one green lacewing larvae/plant (56.3% on egg, 58.3% on nymph and 30.4% on adult stage of the whitefly & 49.9% on egg, 51.0% on nymph and 24.6% on adult stage of the whitefly, respectively). Significantly higher yields of cucumber were recorded from plots with the release rate of three larvae per plant (2047.9 g/plant). Augmentative biological control of B. tabaci under polyhouse conditions with three weekly releases of 2nd instar C. zastrowi sillemi larvae at three larvae per plant can effectively manage whitefly infestation on parthenocarpic cucumber under polyhouse condition.

The Splendour of Glitter: Silver Leaf in barniz de Pasto Objects

This paper presents current findings about the historical use of silver and metallic elements as part of the decorative technique from Colombia known as barniz de Pasto. The results are part of broader ongoing research. The aim is to interpret and assess the introduction of metal as a significant component in the consolidation of the technique. Our research uses well-established imaging techniques (visible light macrophotography; infrared and ultraviolet photography), cross-sections, and elemental mapping from SEM-EDS. The results are compared and interpreted within a holistic framework suggesting the introduction of silver as part of an innovation of the barniz de Pasto technique, either as whole silver leaf sandwiched between layers of mopa-mopa or as “venturine”, obtained by kneading, and therefore fragmenting, silver leaf within mopa-mopa layers.

Sustainable Solutions for Oral Health Monitoring: Biowaste-Derived Triboelectric Nanogenerator.

Oral healthcare monitoring is a vital aspect of identifying and addressing oral dental problems including tooth decay, gum pain, and oral cancer. Day by day, healthcare facilities and regular checkups are becoming more costly and time-consuming. In this context, consumers are moving toward advanced technology, such as bite sensors, to obtain regular data about their occlusal chewing patterns and strength. The triboelectric nanogenerator (TENG) can potentially eliminate the need for a battery by simply converting abundant vibrations from nature or human motion into electrical energy. In this work, biomaterials are obtained from biowastes such as cellulose from wood waste, chitosan from crab shells, and gelatin from fish scales. All wastes are biodegradable, and our work aims at sustainability and waste hierarchy. The single electrode mode-based TENG was designed and fabricated using biodegradable poly(vinyl alcohol) (PVA)-biomaterial composites, rice paper as a substrate, and edible silver leaf as an electrode. The highest electrical output was obtained for PVA/chitosan 10 wt % composite-based TENG (PC10) of about 20 V, 200 nA, and 12 nC. The biomechanical energy harvesting was measured, and powering of LED was demonstrated using a PC10 TENG device. A biocompatible bite sensor based on the TENG was used to measure the biting force of a dummy teeth model to demonstrate its potential use in dental health applications. It indicates the promising future value of disposable oral medication devices without any invasive surgery or injection.

Reflections on the Forms and Arrangements of Surface Images in the Art of Barniz de Pasto, from the 16th to the 19th Century

Flowers, branches, birds, animals, a diversity of geometric combinations and varied scenes create, with great care, an exquisite and delightfully ornamented world. Among symmetries, proportions, chromatic sense, and repeated figures, themes between the sacred and the profane are set and arranged in the artistic surfaces of barniz de Pasto. My reflection is aimed at knowing in greater depth the marvelous creations that the barniz de Pasto painters elaborated in the cultural environment of San Juan de Pasto and San Francisco de Quito, by exploring that visual world, which is part of a group of objects made by overlapping layers of membrane to define figures with the presence of silver leaf, in which a significant relief is generally evident. Understanding how the figures were arranged on the surface of the objects, how they were organized, and what system of composition and other possible artistic resources to control the surfaces existed, leads me to consider that the craftsmen had a similar training to that given in the field of the Spanish painter in several of its modalities. Some of the most noted examples of this neogranadino art will be used as examples. I reflect on three examples from different periods and very different in their configuration: a casket, a cabinet, and a tray, all decorated with barniz de Pasto and with different compositional challenges for the artist. Rather than the physical–mechanical use of materials and supports, I focus on the syntax of the image and the techniques used in the organizational structure and its processes, finding that there were ways of organizing the elements in a specific space and that these came from professional practices associated mainly with painting.

New Insight on Medieval Painting in Sicily: The Virgin Hodegetria Panel in Monreale Cathedral (Palermo, Italy)

The Virgin Hodegetria, located in the Cathedral of Santa Maria Nuova in Monreale, near Palermo (Italy), probably dating the first half of the 13th century, is one of the earliest examples of medieval panel painting in Sicily. A diagnostic campaign was carried out on the panel aiming to identify the constituting materials and the executive technique, as well as to assess the state of conservation for supporting the methodological choice of the restoration intervention. Both non-invasive (X-ray radiography, digital microscope, multispectral imaging, ED-X-ray fluorescence) and micro-invasive (polarised light microscopy, ESEM-EDX, ATR-FTIR spectroscopy and micro-Raman spectroscopy) analyses were performed. According to the results, the executive technique followed the 13th–14th-century Italian painting tradition. A complex structure was applied on the wooden support, consisting of a double layer of canvas and several ground layers of gypsum and glue-based binder. The underdrawing was made by a brush using carbonaceous black pigment. The original palette includes red ochre, red lead, azurite, carbon black and bone black. During the several restorations, mercury-based red, indigo, smalt blue, orpiment and synthetic mars were used. The original silver leaf of the frame was covered with red tin-based lake and subsequently regilded with gold leaf. Proteinaceous and oil binders were also detected.

Impact assessment of natural variations in different weather factors on the incidence of whitefly, Bemisia tabaci Genn. and yellow vein mosaic disease in Abelmoschus esculentus (L.) Moench

Bemisia tabaci Gennadius, also renowned as the silver leaf whitefly, is among the most damaging polyphagous insect pests in many commercially important crops and commodities. A set of field experiments were conducted for three consecutive years i.e., 2018–2020, to investigate the role of variations in rainfall, temperature, and relative humidity on the abundance of B. tabaci in okra (Abelmoschus esculentus L. Moench). In the first experiment, the variety Arka Anamika was cultivated twice a year to analyse the incidence of B. tabaci concerning the prevailing weather factors and the overall pooled incidence recorded during the dry and wet season was 1.34 ± 0.51 to 20.03 ± 1.42 and 2.26 ± 1.08 to 18.3 ± 1.96, respectively. Similarly, it was observed that the highest number of B. tabaci catch (19.51 ± 1.64 whiteflies/3 leaves) was recorded in morning hours between 08:31 to 09:30 a.m. The Yellow Vein Mosaic Disease (YVMD) is a devastating disease of okra caused by begomovirus, for which B. tabaci acts as a vector. In another experiment, screening was conducted to check the relative susceptibility of three different varieties viz., ArkaAnamika, PusaSawani, and ParbhaniKranti against B. tabaci (incidence) and YVMD ((Percent Disease Incidence (PDI), Disease Severity Index (DSI), and Area Under the Disease Progress Curve (AUDPC)). The recorded data was normalized by standard transformation and subjected to ANOVA for population dynamics and PDI. Pearson's rank correlation matrix and Principal Component Analysis (PCA) have been used to relate the influences of various weather conditions on distribution and abundance. SPSS and R software were used to create the regression model for predicting the population of B. tabaci. Late sown PusaSawani evolved as a highly susceptible variety in terms of B. tabaci (24.83 ± 6.79 adults/3leaves; mean ± SE; N = 10) as well as YVMD i.e., PDI (38.00 ± 4.95 infected plants/50plants), DSI (71.6–96.4% at 30 DAS) and AUDPC (mean β-value = 0.76; R2 = 0.96) while early sown Parbhani Kranti least susceptible to both. However, the variety ArkaAnamika was observed as moderately susceptible to B. tabaci and its resultant disease. Moreover, environmental factors were predominantly responsible for regulating the population of insect pests in the field and hence its productivity like rainfall and relative humidity were negative while the temperature was positively correlated with B. tabaci (incidence) and YVMD (AUDPC). The findings are helpful for the farmers to choose need-based IPM strategies than timing-based, which would fit perfectly with the present agro-ecosystems in all ways.

Plant Fungus Chondrostereum purpureum: Also infects humans

Chondrostereum purpureum, is a plant fungus causing silver leaf disorder of plant life, especially of the rose family. It attacks in the main species of the rose family. Hosts with compromised immune system are maximum liable to fungal infection but healthy and immune competent individuals also are frequently pronounced to have fungal infections. In this situation the infections can be related to exposure to a huge inoculum.

Barrier Films and Dressings for the Prevention of Acute Radiation Dermatitis: A Systematic Review and Meta-Analysis.

This systematic review and meta-analysis aimed to evaluate the efficacy of barrier films and dressings in preventing acute radiation dermatitis (RD). OVID Medline, Embase, and Cochrane databases were searched from 1946 to September 2020 to identify randomized controlled trials on the use of barrier films or dressings to prevent RD. For comparable outcomes between studies, pooled effect sizes and 95% confidence intervals (CI) were calculated using the random effects analysis in RevMan 5.4. Fourteen and 11 studies were included in the qualitative and quantitative analyses, respectively. Five types of barrier films used for RD were identified: Hydrofilm, StrataXRT®, Mepitel® Film, 3M™ Cavilon™ No-Sting Barrier Film, and silver leaf nylon dressing. Hydrofilm and Mepitel Film significantly reduced the development of RD grade ≥ 2 in breast and head and neck cancer patients (RR 0.32, 95%CI 0.19, 0.56, p < 0.0001; RR 0.21, 95%CI 0.05, 0.89, p = 0.03, resp.). Moreover, Hydrofilm had a beneficial effect on patient-reported outcomes (PROs) (SMD -0.75, 95%CI -1.2, -0.29, p = 0.001). The meta-analyses on the other barrier films did not show any significant effect. This review and meta-analysis demonstrated that Hydrofilm and Mepitel Film could effectively reduce RD severity and improve PROs. The evidence is generally weak for all the studies on barrier films and dressings due to a limited study number, high risk of bias, small sample sizes, and minimal comparable outcome measures. It's potential has been proven, but future research in this field is recommended to confirm the efficacy of these products and assess real-world feasibility.

Thermally Degradable Inductors with Water-Resistant Metal Leaf/Oleogel Wires and Gelatin/Chitosan Hydrogel Films.

Ingestible electronics monitor biometric information from outside the body. Making them with harmless or digestible materials will contribute to further reducing the burden on the patient's oral intake. Here, considering that the inductive part plays an important role in communications, we demonstrate a degradable inductor fabricated with harmless substances. Such a transient component must meet conflicting requirements for both operation and disassembly. Therefore, we integrated a substrate made of gelatin, a thermally degradable material, and a precision coil pattern made of edible gold or silver leaf. However, gelatin itself lost its initial shape easily due to quick sol-gel changes in physiological conditions. Thus, we managed the gelatin's thermal responsiveness by using a tangle of gelatin/chitosan gel networks and genipin, an organic cross-linking agent, and gained insights into the criteria for developing transient devices with thermo-degradability. In addition, to compensate for the lack of water resistance and low conductivity of thin metal foils, we propose a laminated structure with oleogel (beeswax/olive oil). LCR resonance circuits, by connecting a commercial capacitor to the coil, worked wirelessly in the megahertz band and gradually degraded in a warm-water environment. The presented organic electronics will contribute to the future development of transient wireless communications for implantable and ingestible medical devices or environmental sensors with natural and harmless ingredients.

A Scientific Analysis of Decorative Metal Foil Used in Pouch for the Sutra Embroidered with a Sun and Moon Design Designated as National Folklore Cultural Heritage

Through scientific analysis, this study identified the material characteristics of metal foil decorating the border line and knotting of the National Folklore Cultural Heritage ‘Pouch for the Sutra Embroidered with a Sun and Moon Design’. Through Scanning Electron Microscope-Energy Dispersive Spectroscopy results, it was estimated that silver (Ag) and sulfur (S) were present in the metal foil, and silver leaf was also attached to the medium. S may discolor Ag from yellow to black depending on its concsentration and contact time. Yellow color could not be identified in metal foil at present. But there existed an example of the preparation of a gold-colored flat silver thread; therefore, further research is needed to estimate the original color. The lamella was reddish brown on the back. Aluminum, silicon, and iron were also detected and were the main components found in red soil. This is believed to be the red adhesive in traditional flat gold thread and is considered to be an adhesive-related component of the metal foil. From the gas chromatography mass spectrometry results, the adhesive component was confirmed to be animal glue.

Combining Cultural Tactics and Insecticides for the Management of the Sweetpotato Whitefly, Bemisia tabaci MEAM1, and Viruses in Yellow Squash

The sweetpotato whitefly, Bemisia tabaci MEAM1 Gennadius (Hemiptera: Aleyrodidae), and the complex of viruses it transmits are major limiting factors to squash production in the southeastern United States. At this time, insecticides are extensively relied upon for the management of whiteflies and, indirectly, whitefly-transmitted viruses. The development of a multi-faceted, integrated pest management (IPM) program is needed to increase the sustainability and profitability of squash production. Experiments in 2018 and 2019 evaluated the effects of insect exclusion netting (IEN) in combination with selected pesticides on whitefly population dynamics and virus incidence in greenhouse-grown squash seedlings. Field experiments from 2018 to 2021 evaluated the effects of mulch type (UV-reflective mulch, live mulch, and white plastic mulch), row covers, and insecticides on whitefly population dynamics, silver leaf disorder (SSL) intensity, virus symptom severity, and marketable yield. IEN significantly reduced whiteflies and virus incidence on squash seedlings in the greenhouse study. In the field mulch study, lower whitefly abundance and SSL intensity, as well as reduced virus symptom severity, were observed in plots with reflective mulch compared with white plastic or live mulch. In the insecticide/row cover study, whitefly abundance, SSL intensity, and virus symptom severity were lowest in the row cover and cyantraniliprole- and flupyradifurone-treated plots. Field plots with row covers and those with UV-reflective mulch consistently produced the greatest marketable yields. These findings demonstrate that growers can reduce whitefly and virus pressure and preserve yields in squash production in the southeastern United States by combining cultural and chemical tactics, including row covers, UV-reflective mulch, and select insecticides.

English

Silver leaf whitefly (Bemisia tabaci Gennadius) (Hemiptera: Aleyrodidae) is a polyphagous winged insect pest that causes high yield losses in tomatoes and other vegetable crops globally. To combat the infestation by the silver leaf whitefly and other insects, tomato growers use cultural and synthetic chemical-based methods. However, the silver leaf whitefly continues to dominate the tomato production systems. Some of the reasons for such continued dominion by the silver leaf whitefly in tomato include among other reasons; little understanding of the mechanisms for survival of the insect pest by tomato production stakeholders which consequently results in difficulties in making appropriate pest management decisions, presence of diverse hosts, the ability of the silver leaf whitefly to develop resistance to synthetic pesticides and ineffective techniques used by tomato grower in combating the insect. Of these challenges, this review discusses the mechanisms for survival of the insect, current pest management options and recommendations for a way forward concerning the silver leaf whitefly management in Africa. © 2022 Friends Science Publishers

Synthesis of silver leaves and their potential application for analysis and degradation of phenolic pollutants.

A one‐pot bottom‐up synthesis method was used to synthesise multi‐level leaf‐like nano‐silver (silver leaf) by simply mixing AgNO3, L‐ascorbic acid, Sodium sodium citrate, and polyvinylpyrrolidone (PVP) in the ethanol‐water mixed solvents. Scanning electron microscopy (SEM) characterisations show that the silver leaves have tertiary structures and their sizes are controllable. In addition, silver leaves exhibit excellent Raman enhancement effect (SERS) and chemical catalytic activities for phenolic molecules. Interestingly, the SERS and catalytic activities increase as the size of the silver leaves decrease within a certain range, but when the size is too small, both of these performances weaken. The nanometre size and interstitial structure have a common amplification effect and influence on these activities. The present work not only showed a new method for the synthesis of silver leaves but also could be generalised to find other metallic leaves that could be used as promising heterogeneous catalysts for various reactions. The production of such small‐sized silver leaves will facilitate the analysis of phenolic pollutants through Raman enhancement and treat these pollutants through catalytic degradation.

Resistance to Bemisia tabaci in tomato species and hybrids and its association with leaf trichomes

Chemical insecticides comprise the most widely used method of tomato pest control. Genotypes resistant to pests such as the silver leaf whitefly Bemisia tabaci may contribute towards the decreased use of insecticides to protect the environment. Leaf trichomes play a role in imparting resistance to pests, and exploiting intraspecific and interspecific variability for leaf trichomes in the tomato gene pool is an alternative to speed up introgression of resistance into improved lines or cultivars. We assessed the levels of whitefly resistance and trichome morphology/density in an array of accessions of the tomato gene pool and their hybrids with a tomato cultivar. A commercial cultivar (S. lycopersicum cv. Redencao), six wild species accessions, two S. lycopersicum var. cerasiforme genotypes, and eight intra and interspecific F1 hybrids were tested. The accessions LA 1401 (S. galapagense), AF 19684 (S. peruvianum), PI 127826 (S. habrochaites var. hirsutum), PI 134417 (S. habrochaites var. glabratum), LA 716 (S. pennellii), and RVTC 03 (S. lycopersicum var. cerasiforme) genotypes showed a higher density of glandular trichomes and carried the highest levels of whitefly resistance than the commercial cultivar. Segregating generations from their crosses with the cultivar may be promising sources to select plants with both higher density of glandular trichomes and resistance to whiteflies. Populations derived from S. lycopersicum var. cerasiforme’ RVTC 03’, which is part of intraspecific S. lycopersicum variability, maybe a more convenient source of pest resistance than those derived from interspecific crosses to obtain pest-resistant tomato cultivars.