Aphicidal activity of farnesol against the green peach aphid – Myzus persicae

BACKGROUND: Myzus persicae (Hemiptera: Aphididae) is considered one of most important agricultural pests in the world. It is one of the main pests in protected pepper crops under glasshouse conditions in Southeastern Spain, but its control is limited as a consequence of the few available authorized insecticides and their incompatibility with the natural enemies. Some essential oils and pure compounds such as anise (Pimpinella anisum) or farnesol are repellent and/or toxic to aphids. Their use as a botanical insecticides can be an alternative for aphid control in pepper. RESULTS: The effect of farnesol was evaluated against M. persicae in a new bioassay developed to test the contact effect (aqueous formulation of the products) on aphids in laboratory conditions. Aniseed essential oil, geraniol and (Z)-jasmone at 0.6% causes an aphid mortality of >50%; and farnesol was the most effective (93.67% mortality). Farnesol nanoemulsions between 0.2% and 0.6% were formulated with an IKA-Labor Pilot dispersing machine (7940 rpm for 10 min) using Tween 80 as a surfactant. These formulations were tested on field experiments (glasshouse conditions) on pepper crops for 2 years. Foliar applications of farnesol at a concentration of 0.4% in field conditions causes a high reduction in aphid populations, with efficacies of ≈70–80% with respect to the control, similar to or even higher than the efficacy of the reference pyrethrin insecticide. CONCLUSION: Farnesol showed a great aphicidal effect against M. persicae. The use of this molecule in integrated pest management programs combined with natural enemies is a good option for future control of M. persicae

Aniseed essential oil botanical insecticides for the management of the currant-lettuce aphid

Nasonovia ribisnigri Mosley (Hemiptera: Aphididae) is the most damaging aphid species of lettuce grown in open fields. Populations of N. ribisnigri are developing resistance to insecticides, making their control difficult. Botanicals are an alternative for pest control. Aniseed (Pimpinella anisum L.) is a relevant crop in the production of essential oils. The effect of aqueous nano-formulations of this oil and its main compound (E)-anethole were tested against N. ribisnigri in a growth chamber, a greenhouse (in spring for two years, 2019 and 2020) and in the open field in a plot in the Southeast of Spain (Torrepacheco, Murcia) in May 2019. Aniseed essential oil nanoemulsions were prepared using a laboratory dispersing machine at a high-speed regime (10 min, 7940 revs/min, 15 ◦C) using Tween80 as a surfactant at a 1:2 ratio. Foliar applications of aniseed essential oil at concentrations of 0.2% and 0.4% (0.1 and 0.2 mL respectively) to lettuce plants infested with homogeneous populations of N. ribisnigri reduced the number of insects compared with the control in the laboratory (efficacies > 50%) and greenhouse (efficacies > 25%, 48 h after treatment) experiments. During the field trial, a reduction in the aphid populations was also produced after the application of the products, without any phytotoxic effects observed on the crop. Likewise, (E)-anethole gave similar results as aniseed essential oil (with efficiencies of up to 47% with respect to the control) without damaging the plant

Fumigant Toxicity in Myzus persicae Sulzer (Hemiptera: Aphididae): Controlled Release of (E)-anethole from Microspheres

(E)-anethole is a phenylpropanoid that is the main compound found in the essential oils (EOs) of anise and fennel seeds, and either fumigant or direct contact activity of this compound has been demonstrated against aphids and stored product pests. In this work, solid microspheres were prepared by three methods—oil emulsion entrapment, spray-drying, and complexed with β-cyclodextrin. Fumigation activity of each microsphere preparation was tested against the green peach aphid, Myzus persicae Sulzer (Hemiptera: Aphididae), on pepper leaves. The best insecticidal activity was with (E)-anethole encapsulated in oil emulsion beads and introduced to aphids as a vapour over 24 h, with an LC50 of 0.415 μL/L compared to 0.336 μL/L of vapors from free (E)-anethole. Scanning electron microscopy of the beads revealed a compact surface with low porosity that produced a controlled release of the bioactive for more than 21 d, whilst most of the volatile was evaporated within two days if applied unformulated. Spray drying gave spherical particles with the greatest encapsulated yield (73%) of 6.15 g of (E)-anethole incorporated per 100 g of powder. Further work will be done on improving the formulation methods and testing the solid microspheres in all aphid stages scaling up the experimental assay. It is foreseen that nanotechnology will play a role in future developments of low risk plant protection product

Use of nanoemulsions of plant essential oils as aphid repellents

It is believed that climate change will greatly impact the relative importance of pests. The bird cherry-oat aphid, Rhopalosiphum padi L. is probably the major pest of temperate cereal crops on a world scale, it attacks all the major cereals and pasture grasses. The organic sector is in need of alternative aphicides or products that can repel this pest. In spite of the properties of plant volatiles that allow them to act as insect repellents, there is a lack of such products on the market for the agricultural sector. In this work, we tested a group of essential oils and pure compounds in a laboratory choice bioassay with R. padi (20 replications per product) and the repellency index (R.I.) was computed after 24 h. At 0.15 μl/cm2, aniseed, peppermint and lemongrass essential oils were repellent for apterous females. trans-Anethole and caryophyllene exhibited volatile toxicity to the insects (LD50 =0.11 μl/cm2). R.I. values ranging from 68.8 to 100 were obtained using farnesol, geraniol, cisjasmone, citral, linalool, estragole, pulegone and caryophyllene. Water emulsions of the active products were obtained (nanoemulsions with oil droplets less than 100 nm via ultrasounds for 10 min) and applied at increasing volumes using a computer-controlled spraying apparatus for the bioassay, and a dose response was obtained. Some products were active: carvone increased mobility, whilst cis-jasmone repelled R. padi at a very low dose (0.02 μl/cm2 of the treated leaf). Zetasizer measurements indicated that the smaller the particle size within the nanoemulsion, the higher the activity. Using lecithin (1:2) or lecithin plus glycerol (1:2:1) in addition to a bioactive produced larger negative Z-potential values and therefore more stable formulations without any evident effect on activity

Plant bioactive volatile products and their efficiency in aphid control

The “farm-to-fork strategy” of the European Union aims to reduce dependency on pesticides and towards increased use of low-risk products, such as those based on botanical extracts. A product based on the mixture of the five natural compounds selected for their repellent or insecticidal properties, namely citral, (E)-anethole, farnesol, cis-jasmone and lemon essential oil, was evaluated against Myzus persicae Sulzer (Hemiptera: Aphididae). Three formulations were prepared using various surfactants at different ratios: the first one with Tween80, the second one with soy (Glycine max (l.) Merr.) lecithin and the third one with soy lecithin and sunflower oil (Helianthus annuus L.). The oil-in-water nanoemulsions at 1% were tested in a laboratory study with Petri dishes using a computer-controlled spraying apparatus (equivalent application of 200 l/ha). The mean efficacy was 45%, 71% and 63%, respectively, with a least statistically significant difference (LSD) at 5% comparing the first two formulations. A field experiment (in two pepper, Capsicum anuum L., greenhouses) at Torreblanca Exp. Stat. in Murcia (Spain) followed in April 2020 in which a reduction in aphid populations only occurred by spraying the product formulated with soy lecithin. Phytotoxicity was also observed but was lower in the formulation that contained sunflower oil. Nanoemulsions were characterised using a Zetasizer, and a polydispersion of 2–3 populations of particles, ranging from 15 to 341 nm in size, was found with the Tween80 formulation and bigger sizes (250–438 nm) with the soy lecithin and sunflower oil formulation, which were more stable (Z potential = −28.15 mV). The application of ultrasounds reduces the Z-average to 100 nm in the mixture product with stability for at least 14 days. Another field experiment was repeated in February and April 2021. The plants were sprayed sequentially with the following: a) mixture product at 0.5% formulated with soy lecithin and sunflower oil, b) 3% cottonseed (Gopsyppium hirsutum L.) oil in 3% soap water (Feb.) or 1.5% cottonseed oil in 1.5% soap water (Apr.) and c) cis-jasmone at 0.25% formulated with Tween80. The treatment with the mixture of bioactive volatiles (a) was not more effective than that of the fixed seed oil (b). In February, the instantaneous population growth rate (ri) of aphid populations showed a significant reduction when the plants were sprayed with cottonseed oil. Further research is recommended for the formulation and application methods of the products being develope

Challenges for future food systems: from the Green Revolution to food supply chains with a special focus on sustainability

Finding a food system to feed the growing worldwide population remains a challenge, especially in the current era, where natural resources are being dramatically depleted. From a historical point of view, the Green Revolution, together with biofortification and sustainable intensification, was established as a possible solution to counter hunger and malnutrition during the second half of the 20th century. As a solution, to overcome the limitations attributed to the Green Revolution, food supply chains were developed. The current food system, based on the long food supply chain (LFSC), is characterized by globalization, promoting several advantages for both producers and consumers. However, LFSC has been demonstrated to be unable to feed the global population and, furthermore, it generates negative ecological, environmental, logistical, and nutritional pressures. Thus, novel efficient food systems are required to respond to current environmental and consumers' demands, as is the case of short food supply chain (SFSC). As a recently emerging food system, the evaluation of SFSC sustainability in terms of environmental, economic, and social assessment is yet to be determined. This review is focused on the evolution of food supply systems, starting from the Green Revolution to food supply chains, providing a significant perspective on sustainability.The research leading to these results was supported by MICINN supporting the Ramón y Cajal grant for M. A. Prieto (RYC-2017-22891), the Juan de la Cierva Incorporación for Hui Cao (IJC2020-04605- 5-I) and the FPU grant for A. Soria-Lopez (FPU2020/06140); by Xunta de Galicia for supporting the program (EXCELENCIA-ED431F 2020/12) and by supporting the postdoctoral grant of M. Fraga- Corral (ED481B-2019-096) and the predoctoral grants of M. Carpena (ED481A 2021/313) and of P. Garcia-Oliveira (ED481A-2019/295); and by the European Union through the “NextGenerationEU” program supporting the “Margarita Salas” grant awarded to P. Garcia-Perez. The authors are grateful to Ibero-American Program on Science and Technology (CYTED—AQUA-CIBUS, P317RT0003), to the Bio Based Industries Joint Undertaking (JU) under grant agreement No. 888003 UP4HEALTH Project (H2020-BBI-JTI-2019) that supports the work of P. Otero and P. Garcia-Perez. The JU receives support from the European Union’s Horizon 2020 research and innovation program and the Bio Based Industries Consortium. The project SYSTEMIC Knowledge hub on Nutrition and Food Security, has received funding from national research funding parties in Belgium (FWO), France (INRA), Germany (BLE), Italy (MIPAAF), Latvia (IZM), Norway (RCN), Portugal (FCT), and Spain (AEI) in a joint action of JPI HDHL, JPI-OCEANS and FACCE-JPI launched in 2019 under the ERA-NET ERA-HDHL (No. 696295)

Pigment composition of nine brown algae from the iberian northwestern coastline: influence of the extraction solvente

Brown algae are ubiquitously distributed in the NW coastline of the Iberian Peninsula, where they stand as an underexploited resource. In this study, five solvents were applied to the extraction of pigments from nine brown algae, followed by their determination and quantification by HPLC-DAD. A total of 13 compounds were detected: Six were identified as chlorophylls, six were classified as xanthophylls, and one compound was reported as a carotene. Fucoxanthin was reported in all extracts, which is the most prominent pigment of these algae. Among them, L. saccharina and U. pinnatifida present the highest concentration of fucoxanthin (4.5–4.7 mg g-1 dry weight). Ethanol and acetone were revealed as the most efficient solvents for the extraction of pigments, showing a maximal value of 11.9 mg of total pigments per gram of dry alga obtained from the ethanolic extracts of H. elongata, followed by the acetonic extracts of L. ochroleuca. Indeed, ethanol was also revealed as the most efficient solvent according to its high extraction yield along all species evaluated. Our results supply insights into the pigment composition of brown algae, opening new perspectives on their commercial exploitation by food, pharmaceutical, and cosmeceutical industries.The research leading to these results was supported by MICINN supporting the Ramón y Cajal grant for M.A. Prieto (RYC-2017-22891) and Jianbo Xiao (RYC-2020-030365-I), by Xunta de Galicia for supporting the program EXCELENCIA-ED431F 2020/12, the post-doctoral grant of M. Fraga-Corral (ED481B-2019/096) and the pre-doctoral grant of A.G. Pereira (ED481A-2019/0228). The authors are grateful to the Ibero-American Program on Science and Technology (CYTED—AQUACIBUS, P317RT0003), to the Bio Based Industries Joint Undertaking (JU) under grant agreement No 888003 UP4HEALTH Project (H2020-BBI-JTI-2019) that supports the work of P. Garcia-Perez and C. Lourenço-Lopes and to AlgaMar enterprise (www.algamar.com) for collaboration and algae material provision. JU receives support from the European Union’s Horizon 2020 research and innovation program and the Bio Based Industries Consortium. The authors would also like to thank the EU and FCT for funding through programs UIDB/50006/2020; UIDP/50006/2020 and project PTDC/OCE-ETA/30240/2017—SilverBrain—From sea to brain: Green neuroprotective extracts for nanoencapsulation and functional food production (POCI-01-0145-FEDER-030240).info:eu-repo/semantics/publishedVersio

Seaweed polysaccharides: emerging extraction technologies, chemical modifications and bioactive properties

Nowadays, consumers are increasingly aware of the relationship between diet and health, showing a greater preference of products from natural origin. In the last decade, seaweeds have outlined as one of the natural sources with more potential to obtain bioactive carbohydrates. Numerous seaweed polysaccharides have aroused the interest of the scientific community, due to their biological activities and their high potential on biomedical, functional food and technological applications. To obtain polysaccharides from seaweeds, it is necessary to find methodologies that improve both yield and quality and that they are profitable. Nowadays, environmentally friendly extraction technologies are a viable alternative to conventional methods for obtaining these products, providing several advantages like reduced number of solvents, energy and time. On the other hand, chemical modification of their structure is a useful approach to improve their solubility and biological properties, and thus enhance the extent of their potential applications since some uses of polysaccharides are still limited. The present review aimed to compile current information about the most relevant seaweed polysaccharides, available extraction and modification methods, as well as a summary of their biological activities, to evaluate knowledge gaps and future trends for the industrial applications of these compounds. Key teaching points: Structure and biological functions of main seaweed polysaccharides. Emerging extraction methods for sulfate polysaccharides. Chemical modification of seaweeds polysaccharides. Potential industrial applications of seaweed polysaccharides. Biological activities, knowledge gaps and future trends of seaweed polysaccharides.The research leading to these results was supported by MICINN supporting the Ramón y Cajal grant for M.A. Prieto (RYC-2017-22891); by Xunta de Galicia for supporting the program EXCELENCIA-ED431F 2020/12, the post-doctoral grant of M. Fraga-Corral (ED481B-2019/096), the pre-doctoral grant of P. Garcia-Oliveira (ED481A-2019/295) the program Grupos de Referencia Competitiva (GRUPO AA1-GRC 2018) that supports the work of J. Echave; by University of Vigo for supporting the predoctoral grant of M. Carpena (Uvigo-00VI 131H 6410211) and Becas de Fundación ONCE Programme “Oportunidad al Talento” to support the work of A. Soria-Lopez. Authors are grateful to Ibero-American Program on Science and Technology (CYTED— AQUA-CIBUS, P317RT0003), to the Bio Based Industries Joint Undertaking (JU) under grant agreement No 888003 UP4HEALTH Project (H2020-BBI-JTI-2019) that supports the work of P. Otero. The JU receives support from the European Union’s Horizon 2020 research and innovation program and the Bio Based Industries Consortium. The project SYSTEMIC Knowledge hub on Nutrition and Food Security, has received funding from national research funding parties in Belgium (FWO), France (INRA), Germany (BLE), Italy (MIPAAF), Latvia (IZM), Norway (RCN), Portugal (FCT), and Spain (AEI) in a joint action of JPI HDHL, JPI-OCEANS and FACCE-JPI launched in 2019 under the ERA-NET ERA-HDHL (n° 696295).info:eu-repo/semantics/publishedVersio

Las marismas del sudoeste atlántico como sistemas modelo en ecología de comunidades y ecosistemas

Las marismas del sudoeste atlántico como sistemas modelo en ecología de comunidades y ecosistemas. El uso de ciertas especies como sistemas modelo es común en algunas ramas de la biología (e.g., fisiología, biología molecular, genética). De manera similar, existen ecosistemas muy usados como modelo en ecología. Las marismas, por ejemplo, son sistemas relativamente simples, lo que los hace ideales para realizar experimentos manipulativos de campo. Por ello, son muy utilizadas para entender los determinantes de la estructura y el funcionamiento de comunidades y ecosistemas. Históricamente, la influencia de trabajos realizados en marismas tuvo gran impacto sobre el desarrollo de la ecología de comunidades como disciplina. Sin embargo, la mayor parte de los trabajos que dieron lugar a teorías y modelos generales provienen de unos pocos lugares, por lo que muchas veces, al querer ponerlos a prueba en otros sitios geográficos, los resultados obtenidos parecen no ajustarse a las predicciones. En este artículo hacemos una revisión de algunos trabajos, realizados en las marismas del sudoeste Atlántico durante más de 25 años, que ayudaron no sólo a que entendamos mejor el funcionamiento de las marismas en sí, sino también a extender el conocimiento más allá de estos sistemas en particular. En esta revisión mostramos cómo los resultados obtenidos en las marismas del SO Atlántico contribuyeron al entendimiento de 1) los efectos aislados e interactivos de factores bióticos y abióticos sobre la distribución de especies y hasta la estabilidad de los ecosistemas, 2) el rol integral de especies que pueden actuar simultáneamente como ingenieras y como consumidoras, 3) el balance entre procesos neutrales y determinísticos como reguladores de la estructura comunitaria, y 4) la regulación de los flujos entre ecosistemas. Sin embargo, estas marismas tienen mucho más para ofrecer, no sólo como modelos conceptuales que ayudan a calmar nuestra curiosidad intelectual, sino como ecosistemas clave en la provisión de servicios ecosistémicos.Just as some species are used as model systems in organismal biology (e.g., physiology, genetics), many ecosystems are commonly used as model systems in ecology. Salt marshes, for instance, are great models to perform manipulative field experiments, and thus, were historically used to understand the drivers of community and ecosystem function. Decades of experimental work, indeed, made a strong contribution to community ecology as a discipline, but most of the emerged hypotheses and models were grounded in a few sites. When studies from new sites came onboard, looking to enlarge generalities, their results challenged the prevailing ideas. Here, we review more than 25 years of intense experimentation in South West Atlantic salt marshes, which helped not only to increase the knowledge about salt marsh functioning, but also to expand this knowledge beyond salt marshes helping to refine community and ecosystem function theory. We show that results coming from SW Atlantic marshes significantly contribute to understand 1) the separate and interactive effect of biotic and abiotic stress for species distribution and even for ecosystem stability, 2) the integrated role of species that can function as ecosystem engineers and as consumers, 3) the balance between stochastic and deterministic forces as drivers of community structure, and 4) the regulation of cross-ecosystem fluxes. Nevertheless, we believe SW Atlantic salt marshes still have a lot more to offer, not only as conceptual models that help satisfy our intellectual curiosity, but also as key ecosystems that provide valuable benefits to our societies.Fil: Daleo, Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Alberti, Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Montemayor Borsinger, Diana Ireri. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Giorgini, Micaela. Instituto Nacional de Investigaciones y Desarrollo Pesquero; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Botto, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Pascual, Jesus Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Rocca, Camila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Iribarne, Oscar Osvaldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentin