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Chemical properties and efficacy of Sweet orange essential oil nanoemulsion applied as cold aerosol against two stored product beetles: Presentation
No full textCommon control strategies to manage stored product pests are mainly based on the use of synthetic insecticides and fumigants. Consumer’s demand for pesticide-free food, and the increasing resistance of pests to traditional insecticides, dictate the need to evaluate alternative control methods. For this purpose, many sustainable techniques have been tested for the control of stored product pests. Among them, Citrus essential oils can represent a valid alternative to synthetic insecticides. The effects of Sweet Orange essential oil (EO) nanoemulsion applied as cold aerosol were evaluated against adults of Tribolium confusum du Val (Coleoptera: Tenebrionidae) and Cryptolestes ferrugineus Stephens (Coleoptera: Cucujidae). Both chemical and physical characterization of the EO-based formulation was carried out. The developed formulation had an average size belonging to the nanometer scale and a low polydispersity index. The relatively high zeta potential value confirms the stability over time of the developed formulation. The efficacy of the tested formulation showed a dose-dependent response and the cumulated mortality of the exposed insects increaseduntil 24h of exposure for C. ferrugineus and until 120h for T. confusum. The tested formulation was more effective against T. confusum adults (LD50= 86.30 ppm) than C. ferrugineus ones (LD50= 36.79 ppm). The results of this study coupled with the large availability at reasonable costs of Sweet orange EO, are promising for the potential development of new tools against stored product pests.Common control strategies to manage stored product pests are mainly based on the use of synthetic insecticides and fumigants. Consumer’s demand for pesticide-free food, and the increasing resistance of pests to traditional insecticides, dictate the need to evaluate alternative control methods. For this purpose, many sustainable techniques have been tested for the control of stored product pests. Among them, Citrus essential oils can represent a valid alternative to synthetic insecticides. The effects of Sweet Orange essential oil (EO) nanoemulsion applied as cold aerosol were evaluated against adults of Tribolium confusum du Val (Coleoptera: Tenebrionidae) and Cryptolestes ferrugineus Stephens (Coleoptera: Cucujidae). Both chemical and physical characterization of the EO-based formulation was carried out. The developed formulation had an average size belonging to the nanometer scale and a low polydispersity index. The relatively high zeta potential value confirms the stability over time of the developed formulation. The efficacy of the tested formulation showed a dose-dependent response and the cumulated mortality of the exposed insects increaseduntil 24h of exposure for C. ferrugineus and until 120h for T. confusum. The tested formulation was more effective against T. confusum adults (LD50= 86.30 ppm) than C. ferrugineus ones (LD50= 36.79 ppm). The results of this study coupled with the large availability at reasonable costs of Sweet orange EO, are promising for the potential development of new tools against stored product pests
Protecting stored maize grain against the Sitophilus zeamais with rice husk ash: Poster
No full textMaize weevil (Sitophilus zeamais) is an important insect that affect the maize grain on the field and in storage. There are several ways of controlling this insect but the most commonly used is the use of chemicals. Although these chemicals are very effective, they are often expensive and not available to poor rural farmers resulting in high post-harvest losses of their harvested grains. In this study, the potential of using rice husk ash (RHA) as a protectant against maize weevil during storage was investigated. Cultured maize weevils were introduced into 400g of maize admixed with RHA at concentrations of 5g, 10g and 20g. A control set-up of both Actellic 50EC and no RHA was set-up to compare the effect of the ash treatments on weevil mortality, re-emergence and grain damage. The treatments were replicated and set-up in the lab at room temperature condition. Results showed that, 100% mortality was observed for the Actellic 50EC treatment 5days after application. However, there was no significant difference (p>0.01) after 60 days of storage between the 20g RHA application and the Actellic 50EC relative to weevil mortality, emergence and grain damage. With the 20g RHA admixture recording the highest mortality and suppression effect on adult weevil emergence as well as the lowest grain damage, the use of RHA can provide a significant economic advantage to farmers for storage of maize in tropical developing countries if reliable recommendations on application rate can be made for the protection of stored maize.Maize weevil (Sitophilus zeamais) is an important insect that affect the maize grain on the field and in storage. There are several ways of controlling this insect but the most commonly used is the use of chemicals. Although these chemicals are very effective, they are often expensive and not available to poor rural farmers resulting in high post-harvest losses of their harvested grains. In this study, the potential of using rice husk ash (RHA) as a protectant against maize weevil during storage was investigated. Cultured maize weevils were introduced into 400g of maize admixed with RHA at concentrations of 5g, 10g and 20g. A control set-up of both Actellic 50EC and no RHA was set-up to compare the effect of the ash treatments on weevil mortality, re-emergence and grain damage. The treatments were replicated and set-up in the lab at room temperature condition. Results showed that, 100% mortality was observed for the Actellic 50EC treatment 5days after application. However, there was no significant difference (p>0.01) after 60 days of storage between the 20g RHA application and the Actellic 50EC relative to weevil mortality, emergence and grain damage. With the 20g RHA admixture recording the highest mortality and suppression effect on adult weevil emergence as well as the lowest grain damage, the use of RHA can provide a significant economic advantage to farmers for storage of maize in tropical developing countries if reliable recommendations on application rate can be made for the protection of stored maize
Effectiveness of essential oils from Ngaoundere, against post-harvest insect and fungal pests of maize: Poster
Get PDFSuccessful storage of harvest is a matter of utmost importance in the Sudano-Guinean agro-ecological zone where intense cultivation takes place only once a year. Poor and rudimentary drying/storage methods, high relative humidity as well as inaccessibility to the chemical pesticides leave stored maize at the mercy of insect and fungal attack. Insect attack favours secondary attack by fungi; both leading to a fall in the nutritional, sanitary and organoleptic qualities of the stored maize. Thus, poor peasant farmers are left with the choice of locally available botanicals as alternatives to chemical pesticides. It is against this backdrop that this study seeks to determine the insecticidal efficacy of essential oils from the leaves of Chenopodium ambrosioides and Cupressus sempervirens together with their 50/50 binary combination against the maize weevil, Sitophilus zeamais, and the fungi: Rhizopus stolonifer and Aspergillus flavus on stored maize. Insect mortality and progeny inhibition and the inhibition of fungal invasion were evaluated. Pesticidal activities of both essential oils increased with ascending dose of application. 200 µL/kg of the binary combination caused 100% mortality within 14 days and it completely inhibited progeny production in the weevil. The mixture of the two oils showed additive effects against the weevils and fungi. The two essential oils in isolation significantly inhibited fungal spore invasion in 21 days of storage although A. flavus was less susceptible than R. stolonifer. Therefore both plants could provide active botanical pesticides against S. zeamais and fungal pests in stored maize.Successful storage of harvest is a matter of utmost importance in the Sudano-Guinean agro-ecological zone where intense cultivation takes place only once a year. Poor and rudimentary drying/storage methods, high relative humidity as well as inaccessibility to the chemical pesticides leave stored maize at the mercy of insect and fungal attack. Insect attack favours secondary attack by fungi; both leading to a fall in the nutritional, sanitary and organoleptic qualities of the stored maize. Thus, poor peasant farmers are left with the choice of locally available botanicals as alternatives to chemical pesticides. It is against this backdrop that this study seeks to determine the insecticidal efficacy of essential oils from the leaves of Chenopodium ambrosioides and Cupressus sempervirens together with their 50/50 binary combination against the maize weevil, Sitophilus zeamais, and the fungi: Rhizopus stolonifer and Aspergillus flavus on stored maize. Insect mortality and progeny inhibition and the inhibition of fungal invasion were evaluated. Pesticidal activities of both essential oils increased with ascending dose of application. 200 µL/kg of the binary combination caused 100% mortality within 14 days and it completely inhibited progeny production in the weevil. The mixture of the two oils showed additive effects against the weevils and fungi. The two essential oils in isolation significantly inhibited fungal spore invasion in 21 days of storage although A. flavus was less susceptible than R. stolonifer. Therefore both plants could provide active botanical pesticides against S. zeamais and fungal pests in stored maize
Evaluation of plastic and steel bins for protection of stored maize against Insect Infestation in Ghana: Poster
Get PDFMaize is a staple food in Ghana where there is ever increasing demand for its use to also support poultry and livestock production. However, post-harvest loss of maize is high in Ghana. This study evaluated the effectiveness of plastic and steel bins as bulk storage structures to reduce maize post-harvest loss in Ejura, Ghana during the period from February 2016 to January 2017. Maize pre-disinfested with a solar biomass hybrid dryer was stored in the following treatments: i. a white 7-ton plastic bin filled with untreated maize, ii. agreen 7-ton plastic bin filled with untreated maize, iii.a 6-ton Kikapu steel bin filled with untreated maize, iv. six 50-kg polypropylene (PP) bags filled with maize treated with Betallic Super (80 g pirimiphos-methyl and 15 g permethrin per liter as an emulsifiable concentrate (EC)), and v. six 50-kg PP bags filled with untreated maize ascontrol. Moisture content, insect pests, insect damaged kernels (IDK), grain weight loss, aflatoxin and fumonisin levels data were collected monthly. Sitophilus zeamais, Tribolium castaneum, Cathartus quadricollis, and Cryptolestes ferrugineus were the dominant insect species collected from maize samples. At the end of 12 months of storage, % IDK in the control was >17% while IDK values in the other treatments were <3%. Mean grain weight losses of <1% were recorded in the bin treatments. Mycotoxin levels in the control were above the allowable threshold of 15 ppb. Our data suggest that use of plastic and steel bins has potential to reduce post-harvest loss of maize during storage.Maize is a staple food in Ghana where there is ever increasing demand for its use to also support poultry and livestock production. However, post-harvest loss of maize is high in Ghana. This study evaluated the effectiveness of plastic and steel bins as bulk storage structures to reduce maize post-harvest loss in Ejura, Ghana during the period from February 2016 to January 2017. Maize pre-disinfested with a solar biomass hybrid dryer was stored in the following treatments: i. a white 7-ton plastic bin filled with untreated maize, ii. agreen 7-ton plastic bin filled with untreated maize, iii.a 6-ton Kikapu steel bin filled with untreated maize, iv. six 50-kg polypropylene (PP) bags filled with maize treated with Betallic Super (80 g pirimiphos-methyl and 15 g permethrin per liter as an emulsifiable concentrate (EC)), and v. six 50-kg PP bags filled with untreated maize ascontrol. Moisture content, insect pests, insect damaged kernels (IDK), grain weight loss, aflatoxin and fumonisin levels data were collected monthly. Sitophilus zeamais, Tribolium castaneum, Cathartus quadricollis, and Cryptolestes ferrugineus were the dominant insect species collected from maize samples. At the end of 12 months of storage, % IDK in the control was >17% while IDK values in the other treatments were <3%. Mean grain weight losses of <1% were recorded in the bin treatments. Mycotoxin levels in the control were above the allowable threshold of 15 ppb. Our data suggest that use of plastic and steel bins has potential to reduce post-harvest loss of maize during storage
Determınatıon of toxıcıty of gaseous ozone agaınst adult stages of German Cockroach (Blatella germanıca L.): Poster
Get PDFIn this study, the effects of two different concentrations of ozone gas (16.7 and 33.3 mg / L) against Blatella germanica adults at different exposure times (10, 20, 30, 40 and 50 minutes) were investigated under laboratory conditions. It was determined that the ozone gas had a noticeable effect on mortality of B. germanica adults. In general, ozone gas caused higher paralyisis-mortality rates of B. germanica adults than mortality rates of B.germanica adults at both concentrations and all exposure times. A concentration of 33.3 mg / L of ozone gas with 40 and 50 minute exposure times killed all cockroach adults after 24 hours. On the other hand, 16.7 mg / L concentration of ozone gas with 50 minute exposure time killed 90% of the B. germanica adults after 24 hours. When ozone gas is evaluated in terms of exposure time to B. germanica adults, the concentration of 33.3 mg / L of ozone gas with 10-20 minute exposure times caused 65 % adult mortality, with 30 minute exposure time caused 90% adult mortality and with 50 minute exposure times caused 100 % adult mortality after 24 hours. At a concentration of 16.7 mg / L of ozone gas, as the exposure times increased, the adult mortalities gradually increased after 24 hours and the adult mortality reached 90% with 50 minute exposure times. All these results show that ozone gas (33.3 mg / L) with 40-50 minute exposure times can successfully control B.germanica adults.In this study, the effects of two different concentrations of ozone gas (16.7 and 33.3 mg / L) against Blatella germanica adults at different exposure times (10, 20, 30, 40 and 50 minutes) were investigated under laboratory conditions. It was determined that the ozone gas had a noticeable effect on mortality of B. germanica adults. In general, ozone gas caused higher paralyisis-mortality rates of B. germanica adults than mortality rates of B.germanica adults at both concentrations and all exposure times. A concentration of 33.3 mg / L of ozone gas with 40 and 50 minute exposure times killed all cockroach adults after 24 hours. On the other hand, 16.7 mg / L concentration of ozone gas with 50 minute exposure time killed 90% of the B. germanica adults after 24 hours. When ozone gas is evaluated in terms of exposure time to B. germanica adults, the concentration of 33.3 mg / L of ozone gas with 10-20 minute exposure times caused 65 % adult mortality, with 30 minute exposure time caused 90% adult mortality and with 50 minute exposure times caused 100 % adult mortality after 24 hours. At a concentration of 16.7 mg / L of ozone gas, as the exposure times increased, the adult mortalities gradually increased after 24 hours and the adult mortality reached 90% with 50 minute exposure times. All these results show that ozone gas (33.3 mg / L) with 40-50 minute exposure times can successfully control B.germanica adults
TaReCa – Cascade utilization of horticultural biomass for a resource efficient production of valuable bioactive substances
Get PDFViele pflanzliche Sekundärmetabolite haben antioxidative oder andere bioaktive Eigenschaften, weshalb sie einerseits wichtige Bestandteile der menschlichen Ernährung sind, andererseits aber auch als pharmazeutische Verbindungen oder als Substrat für die chemische Synthese von bioaktiven Substanzen verwendet werden. Pflanzen induzieren die Produktion solcher nutzbaren Sekundärmetabolite wie z.B. Flavonoiden als Reaktion auf abiotischen Stress. Die Produktion von Gemüse und Früchten in Gewächshäusern hinterlässt große Mengen an ungenutzter pflanzlicher Biomasse, welche eine potentielle Ressource für die Gewinnung wertvoller Metabolite darstellt. Durch eine kaskadenartige Verwendung von Gartenbaukulturen zur Produktion von Früchten und Gemüse mit einer anschließenden Gewinnung hochwertiger Substanzen aus der verbleibenden Restbiomasse würde ein erheblicher Mehrwert generiert. Das Projekt TaReCa bearbeitet die Entwicklung einer maßgeschneiderten Kaskadenverwertung von Paprikapflanzen-Restbiomasse aus dem Gartenbau. Dabei soll der pflanzliche Sekundärmetabolismus durch spezifische abiotische Stressbedingungen nach der Fruchternte gezielt induziert werden, um die Konzentrationen der Zielmetaboliten zu steigern. Durch umweltfreundliche und wirtschaftliche Extraktionsprozesse und eine anschließende Verwertung des verbleibenden Pflanzenmaterials in einer Bioraffinerie wird die Wertschöpfungskette erweitert. Eine Analyse der Anwendungsgebiete sowie Untersuchungen zur Akzeptanz der induzierten Inhaltsstoffe, Prozesse und Technologien werden helfen, das Marktpotenzial der Restbiomasse für die Nutzung in Kaskaden zu evaluieren. Die maßgeschneiderte Nutzung von Gartenbaubiomasse durch Lebensmittelproduktion, Extraktion bioaktiver Sekundärmetabolite und Bioraffinerien kann wirtschaftlich relevante, biobasierte Produkte für industrielle Anwendungen erzeugen und somit zur Entwicklung einer nachhaltigen, effizienten und integrierten Bioökonomie beitragen, ohne mit der Lebensmittelproduktion zu konkurrieren.Many plant secondary metabolites have antioxidant or pharmaceutically relevant properties, which makes them important components of the human diet, but also as pharmaceutical compounds or for the chemical synthesis of bioactive substances. Plants induce the production of secondary metabolites, e.g. flavonoids in response to environmental stress stimuli. The production of vegetables and fruits in greenhouses leaves huge amounts of so far under-utilized biomass after fruit harvest, which is a potential source for production of valuable metabolites. A cascade utilization of horticultural crops to produce fruits and vegetables with subsequent extraction of high quality compounds would generate significant added value. The project TaReCa is working on the development of a tailored cascade utilization of bell pepper plant residues from horticulture. The secondary metabolism will be induced by specific abiotic stress treatments after the last fruit harvest, in order to increase the concentrations of the target metabolites. Eco-friendly and economical extraction processes and subsequent utilization of the remaining plant material in a biorefinery will expand the value chain. An analysis of the application areas as well as studies on the acceptance of the induced ingredients, processes and technologies will help to evaluate the market potential of the residual biomass for the proposed cascaded use. The tailored utilization of horticultural biomass in food production, extraction of bioactive secondary metabolites and biorefineries can produce economically relevant bio-based products for industrial applications and thus contribute to the development of a sustainable, efficient and integrated bioeconomy without competing with food production
The role of an efficient characterization of plant extracts for breeding and the transition from wild collection to controlled cultivation
Get PDFDie Inkulturnahme noch nicht fest etablierter Heil- und Gewürzpflanzen steht vor folgendem Dilemma: Einerseits ist eine steigende Nachfrage nach Ware aus kontrolliertem, dokumentiertem, überprüfbarem, heimischem Anbau zu verzeichnen und eine Erhöhung der Anbauflächen dieser Arten politisch gewünscht. Andererseits wird die Anbauware im Preis, je nach Versorgungslage, mit dem Preis der Ware aus Wildsammlungen verglichen. Bei vergleichbaren Qualitäten erhält dann in der Regel die preiswertere Wildsammelware den Vorzug im Einkauf. Dies führt dazu, dass eine kontinuierliche Versorgung der Verarbeitungsbetriebe mit Ware aus kontrolliertem Anbau immer wieder zusammenbricht, da die Anbauer sich nicht auf Preise und Abnahme verlassen können. Auswege aus diesem Dilemma bestehen darin, entweder mit dem Anbau zu warten, bis die Wildsammlungen versagen oder das anzubauende Material qualitativ deutlich von der Wildsammelware abzugrenzen. An den Beispielen Echte Arnika (Arnica montana L.) und Russischer Löwenzahn (Taraxacum kok-saghyz L.E.Rodin) wird gezeigt, dass - vom Wildmaterial ausgehend - in den ersten Selektionszyklen enorm große Zuchtfortschritte erzielt werden können; vorausgesetzt die Ziele sind klar definiert und es steht eine ausreichende Analytik-Kapazität zur Verfügung. Eine solche kann beispielweise mittels moderner Kernspinresonanzspektroskopie (NMR) mit entsprechender software-basierter Datenanalyse realisiert werden und wird im Folgenden, im oben genannten Kontext, diskutiert.The cultivation of not yet well-established medicinal and herbal plants faces the following dilemma: On the one hand there is an increasing demand for goods from controlled, documented, verifiable, domestic cultivation and an increase in the acreage of these species is politically desired. On the other hand, the cultivated product is compared in price, depending on the supply situation, with the price of the product from wild collections. Usually, this results in the use of the cheaper wild collected goods. As a result, the continuous supply of raw material from controlled cultivation to the processing plants collapses time and again as growers can not rely on prices and acceptance. The solution to this dilemma is either to wait with the cultivation until the wild collections fail or the quality of the material to be grown is clearly differentiated from the wild collection. Based on two examples, Arnica (Arnica montana L.) and Russian Dandelion (Taraxacum kok-saghyz L.E.Rodin), is demonstated that - starting from the wild material - high breeding progress can be achieved in the first selection cycles. A necessary precondition is, that the goals are clearly defined and that there is sufficient capacity available to analyze output traits and lead ingredients. Such can be realized for example by means of modern nuclear magnetic resonance (NMR) analysis techniques with appropriate software-based data analysis and will be discussed below
Spur pruning leads to distinctly different phenolic profiles of base sparkling wines than cane pruning
Get PDFWinter pruning is the principal method for regulating yield in viticulture. The aim of this work was to investigate the effectiveness of cane and spur pruning on yield, and on grape and wine composition. Cane and spur pruning were investigated in Vitis vinifera L. \u27Pinot noir\u27 and \u27Chardonnay\u27 vertically-shoot-positioned vines over three seasons. Effects on vine carbohydrates, yield components, leaf area, grape and base wine composition were determined. The canopies of spur pruned vines established more rapidly than cane pruned vines in the 2009/10 season, for both \u27Pinot noir\u27 and \u27Chardonnay\u27. The canopies were denser under spur pruning than cane pruning. Pruning treatment had no effect on total yield for either cultivar in any of the three seasons. Total soluble solids (TSS) and titratable acidity were unaffected by pruning treatment, except in 2012 where TSS and pH were higher for spur pruned \u27Chardonnay\u27 vines. Apart from spur pruned \u27Pinot noir\u27 vine wood being higher in starch in the winter of 2011, overwintering starch and soluble sugar concentrations were not different between pruning treatments for \u27Pinot noir\u27 and \u27Chardonnay\u27. Although not different in yield or basic fruit composition, fruit from spur pruned vines resulted in distinctly different phenolic profiles of base wines, with cane pruning appearing to negatively impact on the low molecular weight phenolics in the wine. The results presented here provide confidence that quality is not lessened, in fact could be improved, by shifting from the industry norm of cane to spur pruning for sparkling wine production in cool climates
Evaluation of intron containing potential reference gene-specific primers to validate grapevine nucleic acid samples prepared for conventional PCR and RT-PCR
Get PDFPreviously we proved the usefulness of an intron containing reference gene, phosphoenolpyruvate carboxylase (PEP) to validate cDNA synthesis for detection of grapevine viruses by conventional RT-PCR from crude nucleic acid preparations. Thus amplicons derived from residual genomic DNA (gDNA) and cDNA can be clearly distinguished by their sizes. Here we designed novel sets of primers which encompass one or two intron containing sequences of grapevine housekeeping genes such as actin, tubulin and elongation factor 1-α. Using these primers the expected sequences were amplified from gDNAs of the tested 24 grapevine cultivars. Thereafter they were challenged using cDNAs prepared from total nucleic acid samples isolated from cambial scrapings of dormant canes, leaf laminas, petioles and in vitro leaves of 12 grapevine cultivars. All of these novel, and the previously published PEP gene-specific primers generated the amplification of the expected shorter DNA fragments without introns. Thus they are suitable to check the quality of nucleic acid preparations and to validate subsequent cDNA synthesis prior to pathogen detection assays