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1.
Stable flies (Stomoxys calcitrans [Diptera: Muscidae] L.) are blood‐feeding synanthropic pests, which cause significant economic losses in livestock. Stable fly antennae contain olfactory sensilla responsive to host and host environment‐associated odours. Field observation indicated that the abundance of stable flies increased significantly in grasslands or crop fields when cattle manure slurry was applied. Major volatile compounds emanating from manure slurry were collected and identified. Behavioural responses of stable flies to those compounds were investigated in laboratory bioassays and field‐trapping studies. Results from olfactometer assays revealed that phenol, p‐cresol and m‐cresol were attractive to adult stable flies. When tested individually, attraction was higher with lower dosages. Stable flies were most attracted to blends of phenol and m‐cresol or p‐cresol. Traps with binary blend lures caught more stable flies in field trials as well.  相似文献   

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3.
Crop residues returned to the soil are important for the preservation of soil quality, health, and biodiversity, and they increase agriculture sustainability by recycling nutrients. Sugarcane is a bioenergy crop that produces huge amounts of straw (also known as trash) every year. In addition to straw, the ethanol industry also generates large volumes of vinasse, a liquid residue of ethanol production, which is recycled in sugarcane fields as fertilizer. However, both straw and vinasse have an impact on N2O fluxes from the soil. Nitrous oxide is a greenhouse gas that is a primary concern in biofuel sustainability. Because bacteria and archaea are the main drivers of N redox processes in soil, in this study we propose the identification of taxa related with N2O fluxes by combining functional responses (N2O release) and the abundance of these microorganisms in soil. Using a large‐scale in situ experiment with ten treatments, an intensive gas monitoring approach, high‐throughput sequencing of soil microbial 16S rRNA gene and powerful statistical methods, we identified microbes related to N2O fluxes in soil with sugarcane crops. In addition to the classical denitrifiers, we identified taxa within the phylum Firmicutes and mostly uncharacterized taxa recently described as important drivers of N2O consumption. Treatments with straw and vinasse also allowed the identification of taxa with potential biotechnological properties that might improve the sustainability of bioethanol by increasing C yields and improving N efficiency in sugarcane fields.  相似文献   

4.
Aggregation of necrophagous larvae has several benefits: the sharing of salivary enzymes (exodigestion), temperature regulation, protection from predators and parasites, etc., and is well developed in blow flies (Diptera: Calliphoridae). The present study focuses on the aggregation mechanism used by the necrophagous larvae of Lucilia sericata Meigen, the common green bottle fly. The ability of single larva to detect and follow a signal (trail) created by conspecifics is investigated initially. A circular ring is drawn in a Petri dish where 20 starved larvae have crawled for a period of 30 min. A naïve (test) larva is then placed in the dish and video‐tracked. Naïve larvae are able to detect the boundaries of the larvae‐crawled area and stay preferentially within this conspecific‐marked zone. In a second step, the orientation of larvae by scanning, a dedicated, ground‐signal detection behaviour of dipteran larvae, is analyzed. Four experimental conditions are tested: control, presence of food, conspecifics, and food + conspecifics. When conspecifics have been previously present in a given area, the scanning behaviour by naïve larvae in this area decreases (both in number and frequency of scans). Accordingly, scanning by necrophagous larvae of L. sericata should be considered not only as locomotion behaviour, but also as a potential way to detect signals from conspecifics for the purpose of aggregation. The chemical composition of the attractant(s), the behavioural effects (attraction or retention) and the implication of larval signalling in the aggregation process are new fields to explore.  相似文献   

5.
The production and use of biofuels have increased rapidly in recent decades. Bioethanol derived from sugarcane has become a promising alternative to fossil fuel for use in automotive vehicles. The ‘savings’ calculated from the carbon footprint of this energy source still generates many questions related to nitrous oxide (N2O) emissions from sugarcane cultivation. We quantified N2O emissions from soil covered with different amounts of sugarcane straw and determined the direct N2O emission factors of nitrogen fertilizers (applied at the planting furrows and in the topdressing) and the by‐products of sugarcane processing (filter cake and vinasse) applied to sugarcane fields. The results showed that the presence of different amounts of sugarcane straw did not change N2O emissions relative to bare soil (control). N‐fertilizer increased N2O emissions from the soil, especially when urea was used, both at the planting furrow (plant cane) and during the regrowth process (ratoon cane) in relation to ammonium nitrate. The emission factor for N‐fertilizer was 0.46 ± 0.33%. The field application of filter cake and vinasse favored N2O emissions from the soil, the emission factor for vinasse was 0.65 ± 0.29%, while filter cake had a lower emission factor of 0.13 ± 0.04%. The experimentally obtained N2O emission factors associated with sugarcane cultivation, specific to the major sugarcane production region of the Brazil, were lower than those considered by the IPCC. Thus, the results of this study should contribute to bioethanol carbon footprint calculations.  相似文献   

6.
This review aims to present an innovative concept of high value added lipids produced by heterotrophic microorganisms, bacteria and fungi, using carbon sources, such as sugars, acids and alcohols that could come from sugarcane vinasse, which is the main byproduct from ethanol production that is released in the distillation step. Vinasse is a rich carbon source and low-cost feedstock produced in large amounts from ethanol production. In 2019, the Brazilian Ministry of Agriculture, Livestock and Food Supply estimates that growth of ethanol domestic consumption will be 58.8 billion liters, more than double the amount in 2008. This represents the annual production of more than 588 billion liters of vinasse, which is currently used as a fertilizer in the sugarcane crop, due to its high concentration of minerals, mainly potassium. However, studies indicate some disadvantages such as the generation of Greenhouse Gas emission during vinasse distribution in the crop, as well as the possibility of contaminating the groundwater and soil. Therefore, the development of programs for sustainable use of vinasse is a priority. One profitable alternative is the fermentation of vinasse, followed by an anaerobic digester, in order to obtain biomaterials such as lipids, other byproducts, and methane. Promising high value added lipids, for instance carotenoids and polyunsaturated fatty acids (PUFAS), with a predicted market of millions of US$, could be produced using vinasse as carbon source, to guide an innovative concept for sustainable production. Example of lipids obtained from the fermentation of compounds present in vinasse are vitamin D, which comes from yeast sucrose fermentation and Omega 3, which can be obtained by bacteria and fungi fermentation. Additionally, several other compounds present in vinasse can be used for this purpose, including sucrose, ethanol, lactate, pyruvate, acetate and other carbon sources. Finally, this paper illustrates the potential market and microbial processes, using microorganisms, for lipid production.  相似文献   

7.
The stable fly, Stomoxys calcitrans (L.), historically has been a pest of livestock in confined operations but seldom of animals on pastures or rangelands. In the past two decades, however, S. calcitrans has become a major pest of cattle and horses on pastures in the midwestern United States. Although there usually is an overabundance of diverse stable fly and house fly, Musca domestica L., larval habitats in confined livestock operations, no larval habitat for stable flies has been clearly identified in the pasture-range environment. Because the winter feeding of hay in round bales results in significant amounts of hay wastage that when mixed with manure, might develop into suitable larval habitats, this study evaluated these areas as developmental sites for the abundant stable flies in pastures. There was a trend for fly traps placed in the vicinity of hay feeding sites to catch more stable flies than those placed distant from these sites. Estimates of stable flies emerging from these sites ranged from 102 to 1225 flies per core sample (25 by 25 cm). The mean number of adult stable flies during May and June 2001 through 2004 correlated negatively with the average minimum temperatures during the preceding winter (November-February) but not with rainfall or temperatures during the spring. These results support the hypothesis that winter feeding sites of hay in round bales are the main source of stable flies in pastures.  相似文献   

8.
Queensland fruit fly, Bactrocera tryoni (“Q‐fly”), is Australia’s most economically important insect pest of horticultural and commercial crops especially in the eastern regions. The sterile insect technique (SIT) has been adopted as an environmentally benign and sustainable approach for management of Q‐fly outbreaks. High‐performance larval diets are required to produce the millions of flies needed each week for SIT. Yeast products contribute amino acids (protein) to fruit fly larval diets, as well as carbohydrate, fat and micronutrients, but there can be substantial variation in the nutritional composition and suitability of yeast products for use in larval diets. Gel larval diets have recently been developed for large‐scale rearing of Q‐fly for SIT, and composition of these diets requires optimization for both performance and cost, including choice of yeast products. We assessed performance of Q‐flies reared on gel larval diets that contained debittered brewer’s yeast (Lallemand LBI2240), hydrolysed yeast (Lallemand FNILS65), inactivated brewer’s yeast (Lallemand LBI2250) and inactivated torula yeast (Lallemand 2160‐50), including blends. Q‐flies performed poorly when reared on diets containing only or mostly hydrolysed yeast in terms of pupal number, pupal weight and percentage of fliers. Performance was also poor on diets containing high proportions of torula yeast. Overall, debittered brewer’s yeast is recommended as the best option for Q‐fly gel larval diet, as it is cheap, readily available, and produces flies with good performance in quality control assays. Inactivated brewer’s yeast produced flies of comparable quality with only a modest increase in cost and would also serve as an effective alternative.  相似文献   

9.
House flies (Musca domestica L.) and stable flies (Stomoxys calcitrans (L.)) (Diptera: Muscidae) are nuisance pests on livestock farms. In the present study we tested the effect of biweekly mass release of Spalangia cameroni Perkins (Hymenoptera: Pteromalidae), the most common parasitoid of house flies and stable flies in southern Norway, on pig premises with scattered fly breeding sites. The study spanned two successive summer periods, with two control and two release units each year. Spalangia cameroni suppressed both house flies and stable flies in one release unit during the first year, and stable flies in one release unit the second year. The apparent lack of success in fly control in the other release units was likely due to immigration of flies in two of the trials and high temperatures in one trial. Recommendations concerning release of S. cameroni in similar pig production premises are given. Handling editor: Torsten Meiners.  相似文献   

10.
Organic compounds and mineral nitrogen (N) usually increase nitrous oxide (N2O) emissions. Vinasse, a by‐product of bio‐ethanol production that is rich in carbon, nitrogen, and potassium, is recycled in sugarcane fields as a bio‐fertilizer. Vinasse can contribute significantly to N2O emissions when applied with N in sugarcane plantations, a common practice. However, the biological processes involved in N2O emissions under this management practice are unknown. This study investigated the roles of nitrification and denitrification in N2O emissions from straw‐covered soils amended with different vinasses (CV: concentrated and V: nonconcentrated) before or at the same time as mineral fertilizers at different time points of the sugarcane cycle in two seasons. N2O emissions were evaluated for 90 days, the period that occurs most of the N2O emission from fertilizers; the microbial genes encoding enzymes involved in N2O production (archaeal and bacterial amoA, fungal and bacterial nirK, and bacterial nirS and nosZ), total bacteria, and total fungi were quantified by real‐time PCR. The application of CV and V in conjunction with mineral N resulted in higher N2O emissions than the application of N fertilizer alone. The strategy of vinasse application 30 days before mineral N reduced N2O emissions by 65% for CV, but not for V. Independent of rainy or dry season, the microbial processes were nitrification by ammonia‐oxidizing bacteria (AOB) and archaea and denitrification by bacteria and fungi. The contributions of each process differed and depended on soil moisture, soil pH, and N sources. We concluded that amoA‐AOB was the most important gene related to N2O emissions, which indicates that nitrification by AOB is the main microbial‐driven process linked to N2O emissions in tropical soil. Interestingly, fungal nirK was also significantly correlated with N2O emissions, suggesting that denitrification by fungi contributes to N2O emission in soils receiving straw and vinasse application.  相似文献   

11.
To identify flystrike‐related volatile compounds in wool from Merino sheep, the attractiveness of wool to Lucilia cuprina Wiedmann (Diptera: Calliphoridae) was examined. First, a selection of wool samples guided by previous knowledge of sheep lines, predicted to be more susceptible or more resistant to flystrike, was tested. The attractiveness of the 10 samples selected was not associated with field susceptibility: two samples from the more resistant line were identified as most attractive and two samples from the more susceptible line were identified as least attractive, based on the behavioural assays with gravid flies. Comparison of the headspace volatiles of these samples, using solid phase microextraction and gas chromatography‐mass spectrometry‐electroantennographic detection, revealed octanal and nonanal to be present in the attractive wool samples that elicited responses from the fly antenna. Furthermore, the two compounds were not present in wool that was least attractive to L. cuprina. In laboratory bioassays, octanal and nonanal evoked antennal and behavioural responses in gravid L. cuprina, thus confirming their potential role as semiochemicals responsible for attracting L. cuprina to Merino sheep.  相似文献   

12.
The Annona fruit borer, Cerconota anonella Sepp., is a serious agricultural pest in many tropical areas of the world. The identification of an attractant for male C. anonella could offer new methods for pest detection and control. A mixture of compounds extracted from female C. anonella elicited antennal depolarization in the male borer. These compounds were identified as octadecanal, 1‐octadecanol, octadecyl acetate, (Z)‐octadec‐9‐enal (Z9‐18:Ald), (Z)‐octadec‐9‐en‐1‐ol (Z9‐18:OH) and [(Z)‐octadec‐9‐enyl] acetate (Z9‐18:Ac) by one‐ and two‐dimensional gas chromatography–mass spectrometry. In laboratory bioassays, synthetic individual compounds as well as synthetic mixtures were found to be attractive to males. In addition, field tests using Delta traps with 1 mg of the ternary mixture composed of Z9‐18:Ac, Z9‐18:Ald and Z9‐18:OH in the ratio of 1 : 3 : 5 caught as many males as traps containing virgin females. The ternary mixture of Z9‐18:Ac, Z9‐18:Ald and Z9‐18:OH was identified as attractant to C. anonella males and can be used to detect and control populations of this insect in Annonaceae plantations.  相似文献   

13.
When female blow flies Lucilia sericata and Phormia regina (Diptera: Calliphoridae) oviposit in aggregations on carrion, even‐aged larval offspring reportedly develop faster, and fewer are parasitized or preyed upon. The benefits of aggregated oviposition equally affect con‐ and heterospecific larvae sharing a resource. The benefits imply that female blow flies engage in coordinated, pheromone‐mediated oviposition behavior. Yet, repeated attempts to identify oviposition pheromones have failed invoking doubt that they exist. Simply by regurgitating and feeding on carrion, flies may produce attractive semiochemicals. If flies were to aggregate in response to feeding flies rather than ovipositing flies, then the semiochemical cue(s) may be associated with the salivary gland. Working with L. sericata and P. regina and using liver as a surrogate oviposition medium, we test the hypotheses, and present data in their support, that (i) gravid or nongravid females ovipositing and/or feeding on liver enhance its attractiveness to gravid and nongravid females; (ii) females respond to semiochemicals from feeding heterospecific females; (iii) females respond equally well to semiochemicals from feeding con‐ and heterospecific females; (iv) macerated head tissues of females applied to liver enhance its attractiveness; and (v) females in direct contact with and feeding on liver, but not when next to yet physically separated from liver, enhance attraction of flies. We conclude that oviposition site‐seeking females do not respond to an oviposition pheromone. Instead, they appear to coopt semiochemicals associated with feeding flies as resource indicators, taking chances that resources are suitable for oviposition, and that ovipositing flies are present.  相似文献   

14.
The stable fly, Stomoxys calcitrans (L.) (Diptera: Muscidae), is one of the most serious pests to livestock. It feeds mainly on cattle and causes significant economic losses in the cattle industry. Standard stable fly control involving insecticides and sanitation is usually costly and often has limited effectiveness. As we continue to evaluate and develop safer fly control strategies, the present study reports on the effectiveness of catnip (Nepeta cataria L.) oil and its constituent compounds, nepetalactones, as stable fly repellents. The essential oil of catnip reduced the feeding of stable flies by >96% in an in vitro bioassay system, compared with other sesquiterpene-rich plant oils (e.g. amyris and sandalwood). Catnip oil demonstrated strong repellency against stable flies relative to other chemicals for repelling biting insects, including isolongifolenone, 2-methylpiperidinyl-3-cyclohexen-1-carboxamide and (1S,2'S)-2-methylpiperidinyl-3-cyclohexen-1-carboxamide. The repellency against stable flies of the most commonly used mosquito repellent, DEET, was relatively low. In field trials, two formulations of catnip oil provided >95% protection and were effective for up to 6 h when tested on cattle. Catnip oil also acted as a strong oviposition repellent and reduced gravid stable fly oviposition by 98%.  相似文献   

15.
Larvae of the greater wax moth (GWM), Galleria mellonella, a destructive pest of the honeybee (Apis mellifera), have been observed to display aggregation behaviours. However, the underlying mechanism by which these larvae come together remains unknown. We hypothesized that the GWM larvae detect, orient towards and utilize conspecific larval chemical cues to aggregate in groups. We used dual‐choice olfactometer assays to investigate the involvement of conspecific larval odours in their aggregation amongst 3–5th instar and 8th instar larvae. The assays revealed that only 8th instar larvae were significantly attracted to their odours and those emanating from newly spun cocoons. Coupled gas chromatography–mass spectrometry (GC‐MS) of larval head space odours analysis revealed the presence of four compounds: nonanal, decanal, tridecane and tetradecane in pupal and mature larval odour extracts. However, using synthetic compounds, behavioural assays showed that only decanal induced significant attraction, therefore, suggesting its role as a major component of the larval aggregation pheromone of GWM. Our findings reveal the involvement of volatile organic compounds in the aggregation behaviour of mature wax moth larvae and thereby offer prospects for the development of an odour‐baited in‐hive trapping management tool for wax moth larva.  相似文献   

16.
The behavioral responses of virgin and mated female Anastrepha striata Schiner (Diptera: Tephritidae) to guava (Psidium guajava L.) or sweet orange (Citrus sinensis L.) were evaluated separately using multilure traps in two‐choice tests in field cages. The results showed that flies were more attracted to guava and sweet orange volatiles than to control (unbaited trap). The physiological state (virgin or mated) of females did not affect their attraction to the fruit volatiles. Combined analysis of gas chromatography coupled with electroantennography (GC‐EAD) of volatile extracts of both fruits showed that 1 and 6 compounds from orange and guava, respectively elicited repeatable antennal responses from mated females. The EAD active compounds in guava volatile extracts were identified by gas chromatography‐mass spectrometry (GC‐MS) as ethyl butyrate, (Z)‐3‐hexenol, hexanol, ethyl hexanoate, hexyl acetate, and ethyl octanoate. Linalool was identified as the only antennal active compound in sweet orange extracts. In field cage tests, there were no significant differences between the number of mated flies captured by the traps baited with guava extracts and the number caught by traps baited with the 6‐component blend that was formulated according to the relative proportions in the guava extracts. Similar results occurred when synthetic linalool was evaluated against orange extracts. From a practical point of view, the compounds identified in this study could be used for monitoring A. striata populations.  相似文献   

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18.
The melon fly, Bactrocera cucurbitae Coquillett, invaded the Hawaiian Island chain in 1895. In 1999, a program sponsored by the USDA-ARS to control melon fly and other tephritid pests in Hawaii over a wide area was initiated on the islands of Hawaii, Maui, and Oahu. To control these flies in an areawide setting, understanding how flies move within the landscape is important. To explore the movement of this fly, we examined the movement of marked, male, sterile, laboratory-reared B. cucurbitae on the island of Hawaii in an agricultural setting. Two releases of dyed, sterile flies consisting of approximately 15,000 flies, were released 6 wk apart. Released flies were trapped back by using Moroccan traps baited with a male attractant. These two releases suggest that in the Hawaiian agricultural areas where the areawide control is being sought, melon flies do not move extensively when there are abundant larval host and adult roosting sites. Over the course of this study, only one fly made it the maximum distance that we could detect fly movement (approximately 2,000 m in 2 wk). From these data, it seems that the flies dispersed throughout the study area but then moved very little thereafter. This is very apparent in the second release where the recovery rate after the second week was still fairly high, suggesting that if there are plenty of host fields and roosting sites the flies are unlikely to move.  相似文献   

19.
Field studies were conducted in Mexico to investigate the possibility of replacing sentinel animals as baits for female New World screwworm Cochliomyia hominivorax (Coquerel) (Diptera: Calliphoridae) with a synthetic odour-bait composed of compounds identified from wounds infested with the larvae of C. hominivorax. Studies using sheep held in stanchions surrounded by an incomplete ring of electrified nets showed that both male and female C. hominivorax were attracted to an unwounded animal (ratio of male : female flies caught 1.11 : 1.00), although they were not observed to land. By contrast, catches associated with unwounded sheep with larval wound fluid applied to shaven shoulders suggested that female C. hominivorax were attracted to (male : female ratio of electrified nets catch 0.14 : 1.00) and landed on the wound fluid but male flies did not respond (male : female ratio alighting on fluid 0.05 : 1.00). In related studies the attractiveness of synthetic blends of 25 electrophysiologically active compounds identified in fluids associated with wounds infested with the larvae of C. hominivorax were tested. The acidic components of the wound fluids were found to attract and elicit a landing response from both male and female flies, whereas the non-acidic components alone caught only low numbers of flies. However, the numbers of male and female flies that were attracted to and landed on a synthetic bait could be increased significantly by increasing the proportion of non-acid to acid components in the lure. In some replicates the most effective blend caught a number of C. hominivorax comparable to that caught by a standard synthetic attractant, Swormlure-4, although, unlike with Swormlure-4, the catch was predominately composed of female flies. It is uncertain whether Swormlure-4 contains compounds that elicit a landing response from male C. hominivorax or whether the synthetic and natural wound odours contain compounds that inhibit a landing response from male C. hominivorax. Further work is required to simplify the blend of compounds needed to attract female flies and to better understand the role of the compounds that elicit behavioural responses from both male and female C. hominivorax before a synthetic substitute can be fully developed to replace sentinel animals.  相似文献   

20.
Flesh flies of the genus Sarcophaga (Diptera: Sarcophagidae) are carrion‐breeding, necrophagous insects important in medical and veterinary entomology as potential transmitters of pathogens to humans and animals. Our aim was to analyse the diversity of gut‐associated bacteria in wild‐caught larvae and adult flesh flies using culture‐dependent and culture‐independent methods. Analysis of 16S rRNA gene sequences from cultured isolates and clone libraries revealed bacteria affiliated to Proteobacteria, Actinobacteria, Firmicutes and Bacteroidetes in the guts of larval and adult flesh flies. Bacteria cultured from larval and adult flesh fly guts belonged to the genera Acinetobacter, Bacillus, Budvicia, Citrobacter, Dermacoccus, Enterococcus, Ignatzschineria, Lysinibacillus, Myroides, Pasteurella, Proteus, Providencia and Staphylococcus. Phylogenetic analysis showed clone sequences of the genera Aeromonas, Bacillus, Bradyrhizobium, Citrobacter, Clostridium, Corynebacterium, Ignatzschineria, Klebsiella, Pantoea, Propionibacterium, Proteus, Providencia, Serratia, Sporosarcina, Weissella and Wohlfahrtiimonas. Species of clinically significant genera such as Ignatzschineria and Wohlfahrtiimonas spp. were detected in both larvae and adult flesh flies. Sequence analysis of 16S rRNA gene libraries supported culture‐based results and revealed the presence of additional bacterial taxa. This study determined the diversity of gut microbiota in flesh flies, which will bolster the ability to assess microbiological risk associated with the presence of these flies. The present data thereby establish a platform for a much larger study.  相似文献   

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