729 research outputs found
Impact of traditional pesticides and new controlled release formulations on Drosophila suzukii
No full textThe spotted wing drosophila, Drosophila suzukii, has become a great threat to European and American producton of soft and stone fruits. Laboratory and field experiments were performed to identify and optimize effective strategies to protect fruit crops from D. suzukii. The first experiment aimed at identification of the efficacy of most commonly insecticides used in Italy to control D. suzukii on cherries. As well as different chemical control strategies applied at commercial cherry orchards in Verona province, North-Eastern Italy, during the growing seasons of 2013, 2014 and 2015 were carried out to determine whether insecticide-based management programs and their timing can provide sufficient crop protection. Moreover, the adherence of those applied pesticides to their maximum residue levels’ (MRLs) requirements set in legal EU regulation for the marketed products was measured. Pre-treating cherries bioassay results revealed that pyrethroids (lambda-cyhalothrin, deltamethrin), spinosyns (spinosad, spinetoram), organophosphates (phosmet, dimethoate) and diamide (cyantraniliprole) were highly efficious, resulting in excellent (>90%) adult D. suzukii mortalities. Moreover, they were able to significantly suppress female fecundity, eggs laying and hatching, immature stages development, and adult emerging as well. Conversely, neonicotinoids (acetamiprid, thiamethoxam, thiacloprid, imidacloprid), Beauveria bassiana, and emamectin-benzoate caused unsatisfactory results. However, dipping infested-cherries bioassays suggested that cyantraniliprole, dimethoate and phosmet (Spada® WDG) can providemore than 10 days residual control for cherries. They caused complete activity, suppressing eggs hatching into larvae. Spinetoram and phosmet (Spada® 200 EC) provided good residual control. While, neonicotinoids (acetamiprid, thiamethoxam, thiacloprid), emamectin-benzoate and pyrethroids (lambda-cyhalothrin, deltamethrin) caused moderate impacts. Moreover, field results proved that two or three insecticide applications were insignificantly able to protect major cherry crops during three consecutive seasons of 2013, 2014 and 2015. Thus, effective D. suzukii control program can be achieved by timely of four applications of insecticides belonging different mode-of-action chemical groups. Except for dimethoate, all residue levels detected in cherries were lower than and completely adherence to their MRLs in force the European Union. It can be concluded that, spinosyns, diamides, organophosphates and pyrethroids may have an important role to protect cherry crop. Neonicotinoids and Beauveria bassiana suggested insignificant activities.
The second experiment identified the efficacy of most commonly insecticides registered in Italy against D. suzukii on strawberries. An open field trial at a commercial strawberry orchard in Verona province, North-Eastern Italy in 2014, and two laboratory bioassay trials in March and September 2015 were performed to determine whether chemical control strategy can provide significant crop protection from D. suzukii. All strategies applied in the field trial significantly succeeded to decrease the damage of strawberries compared to the untreated plants either at 14 or 21 DAFA. The field findings suggested that two treatments of spinosad may provide a suffiecient strawberry-crop protection. Results of pretreating strawberries bioassays confirmed that pyrethroids, spinosyns, avermectin (emamectin-benzoate) and diamide (cyantraniliprole) caused excellent activities, providing adult mortality higher than 90 and 97% at 1 and 2 DAT, respectively. They also provided significant residual activities against D. suzukii life stages emerging after treatment. Incontrast, neonicotinoids, and Beauveria bassiana showed insignificantly results. The same trend of pretreating strawberries bioassay was repeated within the dipping infested-strawberries bioassay, except that acetamiprid showed good residual control against the D. suzukii individuals emerging.
The third experiment investigated potential of the entomopathogenic bacterium, Photorhabdus luminescens as biological agent on D. suzukii. Efficacy of P. luminescens was assessed at different bacterial cell concentrations against third-instar larvae and pupae of D. suzukii under laboratory conditions. Larvae at 4 DAT were significantly affected by bacterial treatments when fed toxins; dipping bioassay was less effective. Following oral and dipping bioassays at concentration of 3.5×108 cells mL-1, total mortalities of 97 and 87% were recorded, respectively. For pupae, the concentration of 3.5×108 cells mL-1 caused a pupae mortality of 64 and 47%, and a total mortality of 100 and 73.33%, respectively in the direct-spray and dipping bioassays. It could be concluded that P. luminescens may play a vital role for managing D. suzukii.
The last work principally focused on preparing and characterizing new controlled release formulations of lambda-cyhalothrin to improve its biological performance against D. suzukii. Chitosan (CS) loaded lambda-cyhalothrin (LC) nanoparticles were prepared using the ionotropic gelation. Tripolyphosphate (TPP) and alginate (ALG) were used as crosslinking agents with CS. The optimum encapsulation efficiency (73.6%) and loading capacity (51.4%) were obtained by a 0.4% CS high molecular weight, 0.3% ALG cross-liking agent, and LC concentration of 1% and at stirring rate of 500 rpm. The nanoparticle size of this formulation was about 416 nm (polydispersity index: 0.447) and a zeta potential of -19.8. Transmission electron microscope (TEM) imaging showed a spherical, smooth and almost homogenous structure for nanoparticles. Fourier transform infrared (FTIR) spectroscopy confirmed linking between tripolyphosphoric groups of TPP with ammonium groups of chitosan, and between ALG and CS in the nanoparticles. The release profile of LC loaded CS nanoparticles cross-linked with TPP exhibited an initial burst release of about 30-40% in the first hour followed by controlled release of 50-60% for the subsequent 5 hours. However, the release profile of LC loaded CS nanoparticles cross-linked with ALG showed a constant sustained release of the pesticide among the time of the release study. All prepared formulations significantly caused adult mortality at 2 and 16 HAT, with a best activity in the formulation of lowest nanoparticle size (278 nm). Most prepared controlled release formulations based on LC suggested activity greater than the efficacy of the commercialize insecticide, Karate-zeon® (lambda cyhalothrin 10% CS)
Insecticidal activity of Photorhabdus luminescens against Drosophila suzukii
No full textDrosophila suzukii causes considerable economic damage to small and thin-skinned fruits including cherry, blueberry, raspberry, grape and strawberry. Since it attacks fruits at the ripening stage, the use of chemical pesticides is limited due to the high risk of residues on fruit. Biological control is thus expected to play an essential role in managing this pest. The Gram-negative bacterium, Photorhabdus luminescens and its symbiotic Heterorhabditis spp. nematode have been shown to be highly pathogenic to insects, with a potential for replacing pesticides to suppress several pests. Insecticidal activity of P. luminescens at different bacterial cell concentrations and its cell-free supernatant were assessed against third-instar larvae and pupae of D. suzukii under laboratory conditions. P. luminescens suspensions had a significant oral and contact toxicity on D. suzukii larvae and pupae, with mortalities up to of 70⁻100% 10 days after treatment. Cell-free supernatant in the diet also doubled mortality rates of feeding larvae. Our results suggest that P. luminescens may be a promising candidate for biological control of D. suzukii, and its use in integrated pest management (IPM) programs is discussed
Laboratory and field trials to identify effective chemical control strategies for integrated management of Drosophila suzukii in European cherry orchards
No full textThe recent spread of the Spotted Wing Drosophila (SWD), Drosophila suzukii, in Europe has created
considerable concern because of the damage recorded on various crops, in particular on sweet cherry,
despite the use of conventional pesticides. Effective chemical control strategies are urgently required to
improve integrated SWD management. Insecticide use should be incorporated in an IPM strategy that
adopts cultural and biological control methods and tools to ensure high protection of cherry production
while fulfilling export market requirements. Laboratory and field trials were conducted in North-Eastern
Italy to identify the most effective and sustainable insecticides to be used against SWD in cherry orchards.
In the laboratory, cherries previously infested by SWD were dipped in insecticide solutions to
assess their effectiveness in controlling eggs and larvae. In other laboratory trials cherries were first
treated with insecticides and then exposed to adults to assess residual activity. A number of chemical
control strategies (including one designed for organic orchards) were then compared in cherry orchards.
These strategies were planned also considering the need to control the European cherry fruit fly Rhagoletis
cerasi L., a key pest of cherry in Europe and elsewhere. A number of formulations based on
cyantraniliprole, spinosad, spinetoram, phosmet, lambda-cyhalothrin and deltamethrin were effective
against different life stages of SWD in the laboratory. SWD control in the field was influenced by the use
of above-mentioned insecticides and the number of applications during the cherry ripening period.
Insecticides selected for the protection of organic cherry orchards were almost ineffective. Some strategies
defined for conventional orchards were also effective against R. cerasi. In most cases (dimethoate
was the exception) insecticide residues were lower than maximum residue limits required by the European
Union to export cherries to major markets. In conditions of high pest pressure, three to four
applications with active ingredients having different modes of action were needed to keep D. suzukii and
R. cerasi damage beneath economic thresholds. Sanitation and harvest management could be helpful in
lowering pesticide use. A number of tactics such as insect-proof nets, biological and cultural methods
should be incorporated for an effective IPM strategy with benefits not only for human and environmental
health but also in terms of the lifetime of currently effective insecticides
Extraction, Chemical Composition and Insecticidal Activities of Lantana camara Linn. Leaf Essential Oils against Tribolium castaneum, Lasioderma serricorne and Callosobruchus chinensis
No full textStorage pests and the food spoilage they cause are problems of great concern. Using essential oil obtained from different plants as an insecticide against these storage pests can be considered an environmentally friendly pest management option. Lantana camara Linn. (family Verbenaceae) is a flowering species, and is also a noxious weed that can proliferate well in nearly all geographical habitats. A biopesticide derived from the essential oil extracted from this plant can offer an effective solution for controlling storage pests. The goal of this study is to extract and analyse the chemical composition of essential oil obtained from L. camara leaves, and assess its effectiveness as a bioactive substance against three storage pests: Tribolium castaneum, Lasioderma serricorne, and Callosobruchus chinensis. The yield of essential oil extracted from L. camara leaves was about 0.24 ± 0.014%. By employing the GC-MS technique, the major phytochemicals contained in L. camara leaf essential oil were identified as caryophyllene (69.96%), isoledene (12%), and α-copaene (4.11%). The essential oil exhibited excellent fumigant toxicity (LC50 of 16.70 mg/L air for T. castaneum, 4.141 mg/L air for L. serricorne and 6.245 mg/L air for C. chinensis at 24 h), contact toxicity (LC50 of 8.93 mg/cm2 for T. castaneum, 4.82 mg/cm2 for L. serricorne and 6.24 mg/cm2 for C. chinensis after 24 h) along with effective repellent activity towards the test insects. In addition, the oil showed no significant phytotoxicity on the germination of paddy seeds. This presents the potential to utilize a weed in developing a biopesticide for effectively managing stored product insects because of its strong bioactivity
Exploring the chemical characterization and insecticidal activities of Curcuma angustifolia roxb. leaf essential oils against three major stored product insects
No full textBotanical pesticides are safe and widely used in pest management. Curcuma angustifolia belongs to the family Zingiberaceae and is a rhizomatous medicinal herb. Following rhizome harvesting, leaves are discarded as waste. However, they can be effectively utilized by extracting essential oils, which are potential biopesticides. The aim of the study is to evaluate the efficacy of the leaf essential oil of Curcuma angustifolia as a potential biopesticide against three stored grain pests, Lasioderma serricorne, Tribolium castaneum, and Callasobruchus chinensis, by their contact, fumigant, and repellent activities. The leaves yield 0.39 ± 0.02 % of oil by hydrodistillation. GC–MS/MS characterization identified curzerenone (18.37 %), geranyl-p-cymene (17.32 %), α-elemenone (13.59 %), eucalyptol (7.58 %) as the main constituents. When exposed to different concentrations of C. angustifolia oil, the test insect displayed noticeably high repellency rates. It also showed better contact toxicity at 24 h, LC50 = 0.22 mg/cm2 for cigarette beetle, LC50 = 0.64 mg/cm2 for red flour beetle, LC50 = 0.07 mg/cm2 for pulse beetle) and fumigation toxicities (LC50 = 10.8 mg/L air at 24 h, for cigarette, LC50 = 29.5 mg/L air for red flour beetle, LC50 = 7.9 mg/L air for pulse beetle). Additionally, a phytotoxicity study was done on paddy seeds, and the results showed no effect on seed germination or seedling growth. It was evident from this study that C. angustifolia oil from waste leaves can be utilized as a botanical pesticide to manage the adults of these storage pests
Phytochemical Characterization of Callistemon lanceolatus Leaf Essential Oils and Their Application as Sustainable Stored Grain Protectants against Major Storage Insect Pests
No full textFood storage has been important since the dawn of agriculture and human settlement. Insect pests cause major losses to food grains during storage and production. Essential oils are good alternatives for chemical insecticides for the management of storage pests. Red bottlebrush, Callistemon lanceolatus, is a flowering plant of the Myrtaceae family. This research work aimed to extract the oil from bottlebrush leaves, and chemically characterize and assess their repellent and insecticidal properties against the cowpea seed beetle, Callasobruchus maculatus (F.) (Coleoptera: Chrysomelidae), cigarette beetle, Lasioderma serricorne (F.) (Coleoptera: Ptinidae), and red flour beetle, Tribolium castaneum (Herbst.) (Coleoptera: Tenebrionidae), for the first time. The essential oil yielded by hydro-distillation of bottlebrush leaves was 1.02 ± 0.01%. GC-MS analysis determined the chemical composition of the volatile oil comprised 1,8-cineole (19.17%), α-terpineol (11.51%), α-pinene (10.28%), and α-Phellandrene (9.55%). The C. lanceolatus leaf oil showed potent repellence, contact toxicity, and fumigation toxic effects. In the contact toxicity assay, at 24 h, the LC50 values were 1.35, 0.52, and 0.58 mg/cm2 for the red flour beetle, cigarette beetle, and cowpea seed beetle, respectively. Likewise, in the fumigation assay observed after 24 h, LC50 values of 22.60, 5.48, and 1.43 μL/L air were demonstrated for the red flour beetle, cigarette beetle, and cowpea seed beetle, respectively. Additionally, there was no significance found by a phytotoxicity assay when the paddy seeds were exposed to C. lanceolatus oil. The results show that the volatile oils from red bottlebrush leaves have the potential to be applied as a biopesticide. Therefore, C. lanceolatus leaf oil can be utilized as a bio-insecticide to control stored product insects
Preparation of Lambda-Cyhalothrin-Loaded Chitosan Nanoparticles and Their Bioactivity against Drosophila suzukii
No full textThe encapsulation of pesticides within nanoparticles is a promising approach of advanced technology in sustainable agriculture. Lambda-cyhalothrin (LC) was encapsulated by the ionotropic gelation technique into chitosan (CS)/tripolyphosphate (TPP) and CS/alginate (ALG) matrixes. CS-LC nanoparticles were characterized, and their efficacy was then evaluated against the key pest of soft fruits in Europe and the United States, Drosophila suzukii. The encapsulation efficiency (74%), nanoparticle yield (80%), polydispersity index (0.341), zeta potential (-23.1 mV) and particle size (278 nm) were determined at the optimum conditions. FTIR confirmed the cross-linkage between CS and TPP/ALG in the nanoparticles. The optimum formula recommended by the fractional factorial design was associated with the formulation variables of CS of high or low molecular weight, cross-linking agent (TPP), LC concentration (1.5% w/v) and stirring rate (1500 rpm), showing the highest desirability value (0.5511). CS-LC nanoparticles of the lowest particle size (278 nm) exhibited the highest percent mortality of D. suzukii males (86%) and females (84%), exceeding that caused by the commercial product (Karate-zeon® 10% CS) at 2 HAT. This is the first work to use the ionic gelation technique to make LC nanoparticles, to the best of our knowledge. The encapsulation of chemical pesticides within biodegradable polymeric nanoparticles could be helpful for establishing a sustainable IPM strategy with benefits for human and environmental health and the lifetime of pesticides
VII kadencja Rady Naukowej CNBOP 2005-2008
No full textAutor przedstawia pracę Rady Naukowej CNBOP na tle ogólnej sytuacji Centrum Naukowo-Badawczego Ochrony Przeciwpożarowej w latach 2005-2008.Author presents work of Scientific Board of CNBOP on background of general situation in Scientific and Research Centre for Fire Protection
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