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The ability to transfer information about the performance, safety, and environmental impacts of a genetically modified (GM) crop from confined field trials (CFTs) conducted in one location to another is increasingly gaining importance in biosafety regulatory assessment and decision-making. The CFT process can be expensive, time-consuming, and logistically challenging. Data transportability can help overcome these challenges by allowing the use of data obtained from CFTs conducted in one country to inform regulatory decision-making in another country. Applicability of transported CFT data would be particularly beneficial to the public sector product developers and small enterprises that develop innovative GM events but cannot afford to replicate redundant CFTs, as well as regulatory authorities seeking to improve the deployment of limited resources. This review investigates case studies where transported CFT data have successfully been applied in biosafety assessment and decision-making, with an outlook of how African countries could benefit from a similar approach.
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Produtos Agrícolas , Plantas Geneticamente Modificadas , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/genética , África , Humanos , Tomada de Decisões , Agricultura/métodos , Agricultura/legislação & jurisprudênciaRESUMO
This study aimed to evaluate the effects of physical measures and the applications of phosphorus fertilizer and soil conditioner on the growth of lettuce (Lactuca sativa) and its uptake of cadmium (Cd). In a solar greenhouse that contained soil enriched with cadmium (Cd) (1.75 ± 0.41 mg/kg) with lettuce used as a test plant, field experimental methods were utilized to explore the influence of physical measures, such as deep plowing and soil covering, and the applications of phosphorus fertilizer, including diammonium phosphate (DAP), calcium magnesium phosphate (CMP), and calcium superphosphate (SSP), and soil conditioners, such as biochar, attapulgite clay, and nano-hydroxyapatite, on the uptake of Cd in lettuce. The results indicated that the concentrations of Cd in the aboveground parts of lettuce were 1.49 ± 0.45, 1.26 ± 0.02, 1.00 ± 0.21, and 0.24 ± 0.13 mg/kg when the soil was plowed 30, 40, and 50 cm deep, respectively, and when the soil was covered with 15 cm, this resulted in reductions of 27.5%, 38.3%, 51.4%, and 88.4%, respectively, compared with the control treatment that entailed plowing to 15 cm. When 75, 150, and 225 kg/ha of phosphorus pentoxide (P2O5) were applied compared with the lack of application, the contents of Cd in the aboveground parts of lettuce increased by 2.0%, 54.5%, and 73.7%, respectively, when DAP was applied; by 52.5%, 48.5%, and 8.1%, respectively, when CMP was applied; and by 13.1%, 61.6%, and 90.9%, respectively, when SSP was applied. When the amounts of biochar applied were 0, 2, 4, 6, 8, 10, and 12 t/ha, the contents of Cd in the aboveground parts of lettuce were 1.36 ± 0.27, 1.47 ± 0.56, 1.80 ± 0.73, 1.96 ± 0.12, 1.89 ± 0.52, 1.44 ± 0.30, and 1.10 ± 0.27 mg/kg, respectively. Under concentrations of 0, 40, 80, 120, 160, and 200 kg/ha, the application of nano-hydroxyapatite resulted in Cd contents of 1.34 ± 0.56, 1.47 ± 0.10, 1.60 ± 0.44, 1.70 ± 0.21, 1.31 ± 0.09, and 1.51 ± 0.34 mg/kg, respectively. The concentrations of Cd in the aboveground parts of lettuce treated with attapulgite clay were 1.44 ± 0.48, 1.88 ± 0.67, 2.10 ± 0.80, 2.24 ± 0.75, 1.78 ± 0.41, and 1.88 ± 0.48 mg/kg, respectively. In summary, under the conditions in this study, deep plowing and soil covering measures can reduce the concentration of Cd in the aboveground parts of lettuce. The application of phosphorus fertilizer increased the concentration of Cd in the aboveground parts of lettuce. The application of higher amounts of DAP and SSP led to greater concentrations of Cd in the aboveground parts of lettuce. The application of higher amounts of CMP caused a lower concentration of Cd in the aboveground parts of lettuce. When biochar, attapulgite clay, and nano-hydroxyapatite were applied, the concentration of Cd in the aboveground parts of lettuce increased in parallel with the increase in the concentration of application when low amounts were applied. In contrast, when high amounts were applied, the concentration of Cd in the aboveground parts of lettuce began to decrease.
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Fusarium wilt, caused by (Fusarium udum Butler), is a significant threat to pigeonpea crops worldwide, leading to substantial yield losses. Traditional approaches like fungicides and resistant cultivars are not practical due to the persistent and evolving nature of the pathogen. Therefore, native biocontrol agents are considered to be more sustainable solution, as they adapt well to local soil and climatic conditions. In this study, five isolates of F. udum infecting pigeonpea were isolated from various cultivars and characterized morphologically and molecularly. The isolate from the ICP 8858 cultivar displayed the highest virulence of 90%. Besides, 100 endophytic bacteria, 100 rhizosphere bacteria and three Trichoderma spp. were isolated and tested against F. udum isolated from ICP 8858 under in vitro conditions. Out of the 200 bacteria tested, nine showed highest inhibition, including Rb-4 (Bacillus sp.), Rb-11 (B. subtilis), Rb-14 (B. megaterium), Rb-18 (B. subtilis), Rb-19 (B. velezensis), Eb-8 (Bacillus sp.), Eb-11 (B. subtilis), Eb-13 (P. aeruginosa), and Eb-21 (P. aeruginosa). Similarly, Trichoderma spp. were identified as T. harzianum, T. asperellum and Trichoderma sp. Notably, Rb-18 (B. subtilis) and Eb-21 (P. aeruginosa) exhibited promising characteristics such as the production of hydrogen cyanide (HCN), cellulase, siderophores, ammonia and nutrient solubilization. Furthermore, treating pigeonpea seedlings with these beneficial microorganisms led to increased levels of key enzymes (POD, PPO, and PAL) associated with resistance to Fusarium wilt, compared to untreated controls. In field trials conducted for four seasons, the application of these potential biocontrol agents as seed treatments on the susceptible ICP2376 cultivar led to the lowest disease incidence. Specifically, treatments T2 (33.33) (P. aeruginosa) and T3 (35.41) (T. harzianium) exhibited the lowest disease incidence, followed by T6 (36.5) (Carbendizim), T1 (36.66) (B. subtilis), T4 (52.91) (T. asperellum) and T5 (53.33) (Trichoderma sp.). Results of this study revealed that, P. aeruginosa (Eb-21), B. subtilis (Rb-18) and T. harzianum can be used for plant growth promotion and management of Fusarium wilt of pigeonpea.
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Cajanus , Fusarium , Doenças das Plantas , Fusarium/patogenicidade , Cajanus/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Agentes de Controle Biológico , Trichoderma/fisiologia , Rizosfera , Microbiologia do Solo , Controle Biológico de Vetores/métodosRESUMO
Forests make immense contributions to societies in the form of ecological services and sustainable industrial products. However, they face major challenges to their viability and economic use due to climate change and growing biotic and economic threats, for which recombinant DNA (rDNA) technology can sometimes provide solutions. But the application of rDNA technologies to forest trees faces major social and biological obstacles that make its societal acceptance a 'wicked' problem without straightforward solutions. We discuss the nature of these problems, and the social and biological innovations that we consider essential for progress. As case studies of biological challenges, we focus on studies of modifications in wood chemistry and transformation efficiency. We call for major innovations in regulations, and the dissolution of method-based market barriers, that together could lead to greater research investments, enable wide use of field studies, and facilitate the integration of rDNA-modified trees into conventional breeding programs. Without near-term adoption of such innovations, rDNA-based solutions will be largely unavailable to help forests adapt to the growing stresses from climate change and the proliferation of forest pests, nor will they be available to provide economic and environmental benefits from expanded use of wood and related bioproducts as part of an expanding bioeconomy.
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Biotecnologia , Florestas , Biotecnologia/métodos , Madeira , Árvores , Mudança ClimáticaRESUMO
This paper presents a general framework for simulating plot data in multi-environment field trials with one or more traits. The framework is embedded within the R package FieldSimR, whose core function generates plot errors that capture global field trend, local plot variation, and extraneous variation at a user-defined ratio. FieldSimR's capacity to simulate realistic plot data makes it a flexible and powerful tool for a wide range of improvement processes in plant breeding, such as the optimisation of experimental designs and statistical analyses of multi-environment field trials. FieldSimR provides crucial functionality that is currently missing in other software for simulating plant breeding programmes and is available on CRAN. The paper includes an example simulation of field trials that evaluate 100 maize hybrids for two traits in three environments. To demonstrate FieldSimR's value as an optimisation tool, the simulated data set is then used to compare several popular spatial models for their ability to accurately predict the hybrids' genetic values and reliably estimate the variance parameters of interest. FieldSimR has broader applications to simulating data in other agricultural trials, such as glasshouse experiments.
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BACKGROUND: Pentastiridius leporinus (Hemiptera: Cixiidae) is the most important vector of syndrome 'basses richesses' (SBR), a new disease that leads to severe economic losses in sugar beet. In this study, different soil tillage methods (ploughing and cultivator) and crops (winter wheat, spring wheat, maize and bare soil) following SBR-infested sugar beet were tested as potential management options in field trials. In the laboratory, the survival and development of first and third instar nymphs on wheat and maize was studied to further assess their suitability as host plants. RESULTS: In five out of seven field sites, reduced soil tillage had no effect on adult planthopper emergence compared to ploughing. In two sites, reduced tillage resulted in higher emergence rates. In nearly all field sites, up to 98.9% fewer emerging adults were detected in bare soil and maize, when compared to winter wheat. Under laboratory conditions, the lowest survival rate was found in first instar nymphs feeding on maize seedlings (4.2%), while 66.7% survived on wheat, over a period of 300 days. In contrast, 73.3% and 70% of third instar nymphs survived on wheat and maize over a period of 150 days. CONCLUSION: Soil tillage had little effect against Pentastiridius leporinus. Maize is a poor host for first instars but a suitable resource for third instar nymphs, the stage which encounters maize under field conditions. Hence, reductions in planthopper emergence in the field were likely caused by starvation due to the long host-free period between sugar beet harvest and the sowing of maize. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Beta vulgaris , Hemípteros , Ninfa , Solo , Zea mays , Animais , Beta vulgaris/crescimento & desenvolvimento , Hemípteros/crescimento & desenvolvimento , Hemípteros/fisiologia , Zea mays/crescimento & desenvolvimento , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Produtos Agrícolas/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimento , Doenças das Plantas/prevenção & controle , Insetos Vetores/crescimento & desenvolvimento , Insetos Vetores/fisiologia , Controle de Insetos/métodosRESUMO
Breeding for resistant crops is a sustainable way to control disease and relies on the introduction of novel resistance genes. Here, we tested three strategies on how to use transgenes from wheat to achieve durable resistance against fungal pathogens in the field. First, we tested the highly effective, overexpressed single transgene Pm3e in the background of spring wheat cultivar Bobwhite in a long-term field trial over many years. Together with previous results, this revealed that transgenic wheat line Pm3e#2 conferred complete powdery mildew resistance during a total of nine field seasons without a negative impact on yield. Furthermore, overexpressed Pm3e provided resistance to powdery mildew isolates from our worldwide collection when crossed into the elite wheat cultivar Fiorina. Second, we pyramided the four overexpressed transgenes Pm3a, Pm3b, Pm3d, and Pm3f in the background of cultivar Bobwhite and showed that the pyramided line Pm3a,b,d,f was completely resistant to powdery mildew in five field seasons. Third, we performed field trials with three barley lines expressing adult plant resistance gene Lr34 from wheat during three field seasons. Line GLP8 expressed Lr34 under control of the pathogen-inducible Hv-Ger4c promoter and provided partial barley powdery mildew and leaf rust resistance in the field with small, negative effects on yield components which might need compensatory breeding. Overall, our study demonstrates and discusses three successful strategies for achieving fungal disease resistance of wheat and barley in the field using transgenes from wheat. These strategies might confer long-term resistance if applied in a sustainable way. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01451-2.
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After conventional oil recovery operations, more than half of the crude oil still remains in a form, which is difficult to extract. Therefore, exploring and developing new enhanced oil recovery (EOR) technologies have always been priority research in oilfield development. Microbial enhanced oil recovery (MEOR) is a promising tertiary oil recovery technology that has received widespread attention from the global oil industry in recent years due to its environmental friendliness, simplicity of operation, and cost-effectiveness. This review presents the: principle, characteristics, classification, recent development, and applications of MEOR technology. Based on hundreds of field trials conducted worldwide, the microbial strains, nutrient systems, and actual effects used in these technologies are summarized, with an emphasis on the achievements made in the development and application of MEOR in China in recent years. These technical classifications involve: microbial huff and puff recovery (MHPR), microbial flooding recovery (MFR), microbial selective plugging recovery (MSPR), and microbial wax removal and control (MWRC). Most of them have achieved good results, with a success rate of approximately 80%. These successful cases have accumulated into rich experiential indications for the popularization and application of MEOR technology, but there are still important yet uncertain factors that hinder the industrialization of this technology. Finally, based on the extensive research and development of MEOR by the authors, especially in both laboratory and industrial large scales, the main challenges and future perspectives of the industrial application for MEOR are presented.
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Background: The aging population in Korea has driven a surge in demand for elderly care services, leading to significant growth in elderly welfare facilities, particularly Adult Daycare Centers (ADCs). However, despite advancements in care facilities, caregivers continue to face challenges in providing suitable elderly care due to difficulties arising from gaps in the latest information on the elderly and their coping abilities. Objective: The objective of this study is to develop and evaluate the effectiveness of the elderly care assistant system, which facilitates the sharing of information and knowledge necessary for elderly care among caregivers. Methods: The ECA system was designed to support knowledge sharing through a knowledge management system based on an ontological knowledge model, with a web-based user interface for improved accessibility. A field trial was conducted at ADC in Seoul from August 17 to September 21, with eight caregivers participating. A mixed-methods approach, involving both surveys and interviews, was employed to gauge the ECA system's effectiveness. Results: The study found that the use of the ECA was beneficial in promoting knowledge sharing among caregivers. Additionally, caregivers noted the potential benefits of using the ECA in conjunction with family caregivers, who can offer additional information and perspectives on elderly care. Conclusions: This study presents preliminary evidence of the potential benefits of a care knowledge sharing system among various caregivers in elderly care. Although the elderly care assistant effectively promotes knowledge sharing, more research is needed to fully understand its impact on elderly care outcomes.
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Hydrocarbonoclastic bacterial strains were isolated from rhizosphere of plants growing in crude oil-contaminated sites of Assam, India. These bacteria showed plant growth-promoting attributes, even when exposed to crude oil. Two independent pot trials were conducted to test the rhizodegradation ability of the bacterial consortium in combination of plants Azadirchta indica or Delonix regia in crude oil-contaminated soil. Field experiments were conducted at two crude oil-contaminated agricultural field at Assam (India), where plants (A. indica or D. regia) were grown with the selected bacterial consortium consisting of five hydrocarbonoclastic bacterial isolates (Gordonia amicalis BB-DAC, Pseudomonas aeruginosa BB-BE3, P. citronellolis BB-NA1, Rhodococcus ruber BB-VND, and Ochrobactrum anthropi BB-NM2), and NPK was added to the soil for biostimulation. The bacterial consortium-NPK biostimulation led to change in rhizosphere microbiome with enhanced degradation of petroleum hydrocarbons (PHs) in soils contaminated with crude oil. After 120 days of planting A. indica + consortium + NPK treatment, degradation of PHs was found to be up to 67%, which was 55% with D. regia with the same treatment. Significant changes in the activities of plant and soil enzymes were also noted. The shift is bacterial community was also apparent as with A. indica, the relative abundance of Proteobacteria, Actinobacteria, and Acidobacteria increased by 35.35%, 26.59%, and 20.98%, respectively. In the case of D. regia, the relative abundance of Proteobacteria, Actinobacteria, and Acidobacteria were increased by 39.28%, 35.79%, and 9.60%, respectively. The predicted gene functions shifted in favor of the breakdown of xenobiotic compounds. This study suggests that a combination of plant-bacterial consortium and NPK biostimulation could be a productive approach to bioengineering the rhizosphere microbiome for the purpose of commercial bioremediation of crude oil-contaminated sites, which is a major environmental issue faced globally.
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Microbiota , Petróleo , Poluentes do Solo , Solo , Poluentes do Solo/análise , Petróleo/metabolismo , Hidrocarbonetos/metabolismo , Biodegradação Ambiental , Bactérias/metabolismo , Microbiologia do SoloRESUMO
AIMS: This study aimed to isolate and characterize endophytic plant growth-promoting (PGP) actinomycetes from the wild medicinal plant Zygophyllum album. METHODS AND RESULTS: Eight actinomycetes were isolated, identified, and screened for their PGP activities to improve the growth and production of wheat plants under low N-inputs. Based on 16S rRNA analysis, the isolated actinobacteria showed high diversity and had multiple in vitro PGP attributes. In pot experiments, Streptomyces sp. NGB-Act4 and NGB-Act6 demonstrated the highest significant PGP activities to enhance the growth of wheat plants under reduced N-inputs. Under various field conditions (high-fertility clay soils and low-fertility sandy soils), in combination with 50% N-dose, the two streptomycetes showed significant increases in grain N% and grain yield of the wheat crop compared with the 50% N-fertilized treatment. Irrespective of soil type, wheat plants inoculated with strain NGB-Act4 produced grain yield and grain N% significantly greater than or comparable to the full N-dose treatment. CONCLUSIONS: This is the first field report on the successful use of endophytic streptomycetes as an effective strategy to improve wheat yield and reduce the use of synthetic N fertilizers.
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Actinobacteria , Actinomycetales , Streptomyces , Triticum/microbiologia , Solo , RNA Ribossômico 16S/genética , Desenvolvimento Vegetal , Grão Comestível , Actinobacteria/genética , Actinomycetales/genéticaRESUMO
The persistence of beneficial microorganisms in the rhizosphere or surrounding soil following their application is a prerequisite for the effective interaction with the plant or indigenous microbial communities in the respective habitats. The goal of the study was to analyze the establishment and persistence of the applied beneficial Trichoderma harzianum (OMG16) strain in the maize root-associated soil depending on agricultural practice (soil management practice, N-fertilizer intensity) in a field experiment. A rapid identification of the inoculated strain OMG16 is essential for its monitoring. We used a culture-based approach coupled to matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis for the rapid identification of the inoculated Trichoderma strain as part of the beneficial microbe consortium (BMc). We isolated 428 fungal isolates from eight treatments of the field experiment. Forty eight percent of the isolated fungi equivalent to 205 fungal isolates were identified as Trichoderma, of which 87% (=179 isolates) were obtained from the fields inoculated with BMc. Gene sequence analysis showed a high similarity of the MALDI-TOF MS-identified Trichoderma, with that of the inoculated Trichoderma harzianum OMG16 confirming the re-isolation of the added beneficial fungus. This study highlighted the use of MALDI-TOF MS analysis as a quick, cost-effective detection and efficient monitoring tool for microbial-based bioinoculants in the field.
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Switchgrass (Panicum virgatum L.) is a promising perennial bioenergy crop that achieves high yields with relatively low nutrient and energy inputs. Modification of cell wall composition for reduced recalcitrance can lower the costs of deconstructing biomass to fermentable sugars and other intermediates. We have engineered overexpression of OsAT10, encoding a rice BAHD acyltransferase and QsuB, encoding dehydroshikimate dehydratase from Corynebacterium glutamicum, to enhance saccharification efficiency in switchgrass. These engineering strategies demonstrated low lignin content, low ferulic acid esters, and increased saccharification yield during greenhouse studies in switchgrass and other plant species. In this work, transgenic switchgrass plants overexpressing either OsAT10 or QsuB were tested in the field in Davis, California, USA for three growing seasons. No significant differences in the content of lignin and cell wall-bound p-coumaric acid or ferulic acid were detected in transgenic OsAT10 lines compared with the untransformed Alamo control variety. However, the transgenic overexpressing QsuB lines had increased biomass yield and slightly increased biomass saccharification properties compared to the control plants. This work demonstrates good performance of engineered plants in the field, and also shows that the cell wall changes in the greenhouse were not replicated in the field, emphasizing the need to validate engineered plants under relevant field conditions.
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Bacillus thuringiensis is a worldwide known bacterium for its capacity to control insect pests thanks to the action of its parasporal crystal. The objective of this paper deals with the history, in some cases unknown, of the study of Bacillus thuringiensis that led it to be a crucial biological alternative in controlling pest insects. How the mode of action for killing insects was understood, as well as the field tests that were carried out to evaluate its effectiveness and to develop the first commercial products, are reflected in this review that presents and discusses the scientific successes and failures that marked the course of B. thuringiensis.
Bacillus thuringiensis es una bacteria conocida mundialmente por su capacidad para controlar insectos plaga, gracias a la acción de su cristal parasporal. El objetivo de esta revisión trata de la historia, en algunos casos desconocida, del estudio de Bacillus thuringiensis que la llevó a ser una importante alternativa biológica en el control de insectos plaga. Cómo se llegó a comprender el modo de acción para matar insectos, así como las pruebas de campo que se realizaron para evaluar su efectividad y lograr desarrollar los primeros productos comerciales están plasmados en esta revisión que presenta y discute los aciertos y desaciertos científicos que marcaron el rumbo de B. thuringiensis.
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The initial compositional analysis of plants plays an important role within the internationally harmonized comparative safety assessment approach for genetically modified plants. Current EFSA guidance prescribes two types of comparison, namely difference tests with regard to a conventional comparator or control, and equivalence tests with regard to a collection of commercial reference varieties. The experience gained so far shows that most of the statistically significant differences between the test and control can be discounted based on the fact that they are still within equivalence limits of reference varieties with a presumed history of safe use. Inclusion of a test variety and reference varieties into field trial design, and of the statistical equivalence test would already suffice for the purpose of finding relevant parameters that warrant further assessment, hence both the inclusion of a conventional counterpart and the performance of difference testing can be omitted. This would also allow for the inclusion of safety testing regimes into plant variety testing VCU (value for cultivation and use) or other, independent variety trials.
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Produtos Agrícolas , Alimentos Geneticamente Modificados , Produtos Agrícolas/genética , Plantas Geneticamente Modificadas/genéticaRESUMO
BACKGROUND: Incompatible insect technique (IIT) is a population suppression approach based on the release of males with manipulated Wolbachia infection inducing egg inviability in wild females. We here present results of multiple field releases of incompatible ARwP males carried out in 2019 in a 2.7-ha green area within urban Rome (Italy) to assess the effect on Aedes albopictus egg viability. Data are compared with results obtained in 2018, when the approach was tested for the first time in Europe. RESULTS: An average of 4674 ARwP males were released weekly for 7 weeks, resulting in a mean ARwP:wild male ratio of 1.1:1 (versus 0.7:1 in 2018). Egg-viability dynamics in ovitraps significantly varied between treated and control sites, with an estimated overall reduction of 35% (versus 15% in 2018). The estimated proportion of females classified as mated with ARwP males was 41.8% and the viability rate of eggs laid by these females (9.5%) was on average significantly lower than that of females only mated with wild males (87.8%); however, high variability in fertility was observed. Values of ARwP male competitiveness were 0.36 and 0.73 based on the overall viability rate of eggs in ovitraps and on female fertility, respectively; thus, well above the conventional 0.2 threshold for an effective suppressive impact in the field. CONCLUSIONS: Results further support the potential of IIT as a tool to contribute to Ae. albopictus control in the urban context, stressing the need for larger field trials to evaluate the cost-efficacy of the approach in temperate regions. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Aedes , Wolbachia , Animais , Masculino , Feminino , Controle de Mosquitos/métodos , Fertilidade , ItáliaRESUMO
Firefly flashes are well-known visual signals used by these insects to find, identify, and choose mates. However, many firefly species have lost the ability to produce light as adults. These "unlighted" species generally lack developed adult light organs, are diurnal rather than nocturnal, and are believed to use volatile pheromones acting over a distance to locate mates. While cuticular hydrocarbons, which may function in mate recognition at close range, have been examined for a handful of the over 2000 extant firefly species, no volatile pheromone has ever been identified. In this study, using coupled gas chromatography - electroantennographic detection, we detected a single female-emitted compound that elicited antennal responses from wild-caught male winter fireflies, Photinus corruscus. The compound was identified as (1S)-exo-3-hydroxycamphor (hydroxycamphor). In field trials at two sites across the species' eastern North American range, large numbers of male P. corruscus were attracted to synthesized hydroxycamphor, verifying its function as a volatile sex attractant pheromone. Males spent more time in contact with lures treated with synthesized hydroxycamphor than those treated with solvent only in laboratory two-choice assays. Further, using single sensillum recordings, we characterized a pheromone-sensitive odorant receptor neuron in a specific olfactory sensillum on male P. corruscus antennae and demonstrated its sensitivity to hydroxycamphor. Thus, this study has identified the first volatile pheromone and its corresponding sensory neuron for any firefly species, and provides a tool for monitoring P. corruscus populations for conservation and further inquiry into the chemical and cellular bases for sexual communication among fireflies.
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Besouros , Atrativos Sexuais , Animais , Feminino , Masculino , Vaga-Lumes/fisiologia , Besouros/fisiologia , Feromônios , Atrativos Sexuais/farmacologia , Atrativos Sexuais/análise , Cromatografia GasosaRESUMO
A new biopreparation is developed to clean soils from oil pollution in the arid climate of the Republic of Kazakhstan. The biopreparation includes bacterial strains R. qingshengii F2-1, R. qingshengii F2-2, and P. alloputida BS3701. When using the biopreparation in a liquid mineral medium with 15% crude oil, laboratory studies have revealed degradation of 48% n-alkanes and 39% of PAHs after 50 days. The effectiveness of the biopreparation has been demonstrated in field experiments in the soil contaminated with 10% crude oil at the K-Kurylys landfill, Republic of Kazakhstan. During the six-month field experiment, the number of oil degraders reached 107 CFU/g soil, which degraded 70% of crude oil by the end of the experiment.
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Winter oilseed rape (Brassica napus) is one of the largest crops in Europe and the cabbage stem flea beetle Psylliodes chrysocephala is one of its major pests. Since the ban of neonicotinoids for seed treatment, farmers apply pyrethroids in autumn to control the cabbage stem flea beetle. Current studies show that the insect develops resistance to this group of chemicals. Biological control with entomopathogenic nematodes (EPNs) represents a possible, environmentally friendly alternative control measure. In the present work, we considered three strategies to control the cabbage stem flea beetle: applying the nematodes against the first larval stage in the soil, against the second and third larval stages inside the plant or against the adult beetles. In laboratory experiments, we found the third larval instar to be the most susceptible stage and the adult beetle the less susceptible one. Steinernema feltiae and the cold active SDT1-IL1 Heterorhabditis bacteriophora strain, with a reduction potential of 89 and 76 %, respectively, proved to be the most virulent EPNs against P. chrysocephala in pot experiments at 15 °C. Moreover, we performed four field trials to test the efficacy of H. bacteriophora and S. feltiae against the larvae. The highest reduction in the field trials was 45% and 39%, obtained with SDT1-IL1 and a mixture of H. bacteriophora and S.feltiae, respectively. The present study provides preliminary information about the potential of EPNs to control P. chrysocephala and represents a start point for the development of a competitive and sustainable alternative to pyrethroids.
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Brassica napus , Besouros , Piretrinas , Rabditídios , Animais , Controle Biológico de Vetores , LarvaRESUMO
BACKGROUND: Velvetleaf (Abutilon theophrasti Medik.), primarily a cropland weed, exerts adverse impacts on the productivity of various crops, including soybean (Glycine max L.), wheat (Triticum aestivum L.), and maize (Zea mays L.), by hindering their vegetative growth. However, the interference mechanism of velvetleaf on the three crops remains unclear. RESULTS: The inhibitory effect of velvetleaf water extract on the germination and growth of soybean, wheat, and maize was determined in pot experiments and field trials. Four phenolic acids were identified as allelochemicals: protocatechuic acid (PA), gallic acid (GA), chlorogenic acid (CHA), and vanillic acid (VA). These allelochemicals were detected in different parts (leaves, roots, and stems) of velvetleaf, and in the rhizosphere soil of tested crops over the range of 1.19-556.23 µm kg-1 . These allelochemicals were administered in approximate concentrations as in velvetleaf roots and rhizosphere soil, and their effects varied with crop species and velvetleaf parts. The allelochemicals generally had low-dose stimulation and high-dose inhibition effects on the growth of soybean, wheat, and maize. Furthermore, the biomass distribution of these crops was affected by allelochemicals in the soil. In field trials, the allelochemicals significantly (P < 0.05) inhibited the growth of all tested crops over the whole growth period, and PA showed a significant (P < 0.05) inhibitory effect on the yield of soybean, wheat, and maize. CONCLUSION: GA, PA, CHA, and VA in velvetleaf aqueous extracts were identified as allelochemicals that play an inhibitory role on three crops. © 2022 Society of Chemical Industry.