7850 research outputs found
Sort by
Population growth and development of Liposcelis obscurus Broadhead (Psocodea: Liposcelididae) at constant temperatures and relative humidities: Presentation
No full textThe effects of nine temperatures (22.5, 25, 27.5, 30, 32.5, 35, 37.5, 40, and 42.5°C) and four RHs (43, 55, 63, and 75%) on the population growth and development of the parthenogenetic Liposcelis obscurus Broadhead (Psocodea: Liposcelididae) were investigated in laboratory studies. Results showed that L. obscurus did not survive at 43% RH at all temperatures tested. At 55% RH, L. obscurus survived at 22.5, 25, and 27.5°C; none survived at 42.5°C and =63% RH. Liposcelis obscurus survived and the population increased 56–fold from an initial population of five adult females at 42.5°C and =75% RH. Population growth was highest at 40°C and 75% RH, where population increase was 215-fold. Liposcelis obscurus has three-to-five nymphal instars, and the percentages of third, fourth, and fifth instars were 52, 41, and 7%, respectively. Temperature-dependent developmental equations were developed for L. obscurus eggs, individual nymphal, combined nymphal, and combined immature stages. Liposcelis obscurus populations grew much faster at 30–42.5oC and 75% RH. These data provide a better understanding of L. obscurus population dynamics, and can be used to develop effective management strategies for this psocid.The effects of nine temperatures (22.5, 25, 27.5, 30, 32.5, 35, 37.5, 40, and 42.5°C) and four RHs (43, 55, 63, and 75%) on the population growth and development of the parthenogenetic Liposcelis obscurus Broadhead (Psocodea: Liposcelididae) were investigated in laboratory studies. Results showed that L. obscurus did not survive at 43% RH at all temperatures tested. At 55% RH, L. obscurus survived at 22.5, 25, and 27.5°C; none survived at 42.5°C and =63% RH. Liposcelis obscurus survived and the population increased 56–fold from an initial population of five adult females at 42.5°C and =75% RH. Population growth was highest at 40°C and 75% RH, where population increase was 215-fold. Liposcelis obscurus has three-to-five nymphal instars, and the percentages of third, fourth, and fifth instars were 52, 41, and 7%, respectively. Temperature-dependent developmental equations were developed for L. obscurus eggs, individual nymphal, combined nymphal, and combined immature stages. Liposcelis obscurus populations grew much faster at 30–42.5oC and 75% RH. These data provide a better understanding of L. obscurus population dynamics, and can be used to develop effective management strategies for this psocid
Evaluation of the attractiveness of an organic litter compared to breeding substrate: Poster
Get PDFIn a pet shop warehouse, stored food pest insects can develop in various preserved animal feeds (dog’s pasta, puffed rice, kibble). However, there is another commodity that is rarely considered, such as the organic litter which is composed of bran, flours and other residues of the screening of corn that may result attractive to the same pest insects. The purpose of this laboratory test was to evaluate the attractiveness of organic litters on Plodia interpunctella, Tribolium confusum, Oryzaephilus surinamensis in comparison with breeding substrate. The results confirmed that the test insects were attracted by the breeding substrate rather than by the organic litter.In a pet shop warehouse, stored food pest insects can develop in various preserved animal feeds (dog’s pasta, puffed rice, kibble). However, there is another commodity that is rarely considered, such as the organic litter which is composed of bran, flours and other residues of the screening of corn that may result attractive to the same pest insects. The purpose of this laboratory test was to evaluate the attractiveness of organic litters on Plodia interpunctella, Tribolium confusum, Oryzaephilus surinamensis in comparison with breeding substrate. The results confirmed that the test insects were attracted by the breeding substrate rather than by the organic litter
The developmental parameters of the minute brown scavenger beetle Dienerella argus (Coleoptera: Latridiidae): Poster
Get PDFAdults and larvae of Dienerella argus (Reitter) (Coleoptera: Latridiidae) feed on fungi and are frequently found in indoor, moldy areas. The basic biology of this species, other than its feeding habits, has not been determined. In this study, the developmental parameters of the beetle were investigated using dried hyphae and conidia from three fungi that are common in living areas. The developmental periods of the beetle on Cladosporium cladosporioides, Penicillium citrinum, and P. decumbens were examined at 16, 20, 24, 28, 32 °C / 70–75 % RH under dark conditions. The low developmental threshold temperatures and thermal constants calculated from egg to adult emergence were 10.5 °C and 526 DD (degree day), 9.0 °C and 500 DD, and 10.9 °C and 370 DD on C. cladosporioides, P. citrinum, and P. decumbens, respectively. These developmental parameters indicate that these beetles can breed year-round in indoor areas that are in air-conditioned facilities.Adults and larvae of Dienerella argus (Reitter) (Coleoptera: Latridiidae) feed on fungi and are frequently found in indoor, moldy areas. The basic biology of this species, other than its feeding habits, has not been determined. In this study, the developmental parameters of the beetle were investigated using dried hyphae and conidia from three fungi that are common in living areas. The developmental periods of the beetle on Cladosporium cladosporioides, Penicillium citrinum, and P. decumbens were examined at 16, 20, 24, 28, 32 °C / 70–75 % RH under dark conditions. The low developmental threshold temperatures and thermal constants calculated from egg to adult emergence were 10.5 °C and 526 DD (degree day), 9.0 °C and 500 DD, and 10.9 °C and 370 DD on C. cladosporioides, P. citrinum, and P. decumbens, respectively. These developmental parameters indicate that these beetles can breed year-round in indoor areas that are in air-conditioned facilities
Stored product insects at a rice mill: Temporal and spatial patterns and implications for pest management: Presentation
No full textMonitoring is fundamental to integrated pest management programs since it provides feedback on effectiveness of prevention programs and helps with targeting interventions as needed and evaluating their effectiveness. Rice mills are spatially complex facilities that have a combination of rough rice storage bins, buildings where rice is milled and processed, and warehouses and bulk storage bins where finished product is held before shipment. Each of these structures can have its own suite of insect species, different levels of risk, as well as different suites of management tools available. At a large rice mill in Brazil, stored product insect activity was monitored using food bait traps placed around rough rice receiving areas and storage bins; inside building containing white rice mill, rice flour mill, and packaging; and inside building for processing parboiled rice. The facility was monitored from 2010 to 2018 with 100 traps. Major pest species recovered at the facility included Sitophilus oryzae, Sitophilus zeamais, Rhyzopertha dominica, Tribolium castaneum, Cryptolestes ferrugineus, Ahasverus advena, Oryzaephilus surinamensis, Typhaea stercorea, Anthicus floralis, and Nitidulidae species. Temporal and spatial patterns in abundance were evaluated for each of the major species and for major functional groups (primary feeders, secondary feeders, and fungal feeders). Monitoring data generated was used to guide pest management programs and also provided the information needed to develop management thresholds.Monitoring is fundamental to integrated pest management programs since it provides feedback on effectiveness of prevention programs and helps with targeting interventions as needed and evaluating their effectiveness. Rice mills are spatially complex facilities that have a combination of rough rice storage bins, buildings where rice is milled and processed, and warehouses and bulk storage bins where finished product is held before shipment. Each of these structures can have its own suite of insect species, different levels of risk, as well as different suites of management tools available. At a large rice mill in Brazil, stored product insect activity was monitored using food bait traps placed around rough rice receiving areas and storage bins; inside building containing white rice mill, rice flour mill, and packaging; and inside building for processing parboiled rice. The facility was monitored from 2010 to 2018 with 100 traps. Major pest species recovered at the facility included Sitophilus oryzae, Sitophilus zeamais, Rhyzopertha dominica, Tribolium castaneum, Cryptolestes ferrugineus, Ahasverus advena, Oryzaephilus surinamensis, Typhaea stercorea, Anthicus floralis, and Nitidulidae species. Temporal and spatial patterns in abundance were evaluated for each of the major species and for major functional groups (primary feeders, secondary feeders, and fungal feeders). Monitoring data generated was used to guide pest management programs and also provided the information needed to develop management thresholds
Use of a 3D finite element model for post fumigation phosphine movement analysis: Presentation
No full textPhosphine is a dangerous gas commonly used in fumigations throughout the world. Grain that has not fully released the phosphine it absorbed during fumigation may continue to desorb phosphine into the headspace of a storage structure. U.S. OSHA standards for handling phosphine state the acceptable limit at 0.3 ppm. If this limit is exceeded grain handling may become dangerous. It is important to understand the process of phosphine venting and desorption in order to ensure safe handling of fumigated grain in silos and during shipments. In order to achieve this, the venting and release of phosphine was studied on location in a well-sealed grain silo in Lake Grace, Western Australia, to serve as a set of data for verification of a computational model. This situation was then modeled using a 3D finite element model and compared to the real world results. Results were calculated using two fumigant desorption models based on previous literature, a reversed sorption model and an air-grain equilibrium model. Simulations reproduced accurate trends of desorption but did not accurately reproduce the quantity of fumigant, with a 55.5% error for the model based on reversed sorption equations and 86.3% error for the air-grain equilibrium based model. For both models, simulations were conducted to compare the effectiveness of existing grain venting regulations at producing grain that is within safe handling limits. These results highlight the necessity for continued desorption research and the importance of following venting guidelines.Phosphine is a dangerous gas commonly used in fumigations throughout the world. Grain that has not fully released the phosphine it absorbed during fumigation may continue to desorb phosphine into the headspace of a storage structure. U.S. OSHA standards for handling phosphine state the acceptable limit at 0.3 ppm. If this limit is exceeded grain handling may become dangerous. It is important to understand the process of phosphine venting and desorption in order to ensure safe handling of fumigated grain in silos and during shipments. In order to achieve this, the venting and release of phosphine was studied on location in a well-sealed grain silo in Lake Grace, Western Australia, to serve as a set of data for verification of a computational model. This situation was then modeled using a 3D finite element model and compared to the real world results. Results were calculated using two fumigant desorption models based on previous literature, a reversed sorption model and an air-grain equilibrium model. Simulations reproduced accurate trends of desorption but did not accurately reproduce the quantity of fumigant, with a 55.5% error for the model based on reversed sorption equations and 86.3% error for the air-grain equilibrium based model. For both models, simulations were conducted to compare the effectiveness of existing grain venting regulations at producing grain that is within safe handling limits. These results highlight the necessity for continued desorption research and the importance of following venting guidelines
Anti-termitic properties of Jatropha (Jatropha curcas L.) on wood termites (Macrotermes bellicosus (Smeathman): Presentation
Get PDFThe efficacy of Jatropha curcas in the management of wood termites, (Macrotermes bellicosus) was carried out in the Teaching and Research Farm of the Department of Forestry and Wildlife Resources Management. University of Calabar. The experiment consisted of 5 levels of J. curcas oil (0, 0.5, 1.0, 1.5 and 2.0) and a corresponding quantity in powder, replicated 4 times and arranged in Randomized Completely Block Design (RCBD). Each concentration was tested on 20 unsexed adult wood termite placed in grave yard of 8cm x 8cm. Data on mortality rate was taken at 12 hourly up to 72 hours. The result from the experiment showed that J. curcas oil was significantly efficacious compared with J. curcas powder both in the field and in the laboratory. It was observed that there was progressive increase in mortality rate due to increased concentration and time duration. The management of termite using J. curcas should be encouraged due to its environmental friendliness and should also be incorporated into integrated pest management (IPM).The efficacy of Jatropha curcas in the management of wood termites, (Macrotermes bellicosus) was carried out in the Teaching and Research Farm of the Department of Forestry and Wildlife Resources Management. University of Calabar. The experiment consisted of 5 levels of J. curcas oil (0, 0.5, 1.0, 1.5 and 2.0) and a corresponding quantity in powder, replicated 4 times and arranged in Randomized Completely Block Design (RCBD). Each concentration was tested on 20 unsexed adult wood termite placed in grave yard of 8cm x 8cm. Data on mortality rate was taken at 12 hourly up to 72 hours. The result from the experiment showed that J. curcas oil was significantly efficacious compared with J. curcas powder both in the field and in the laboratory. It was observed that there was progressive increase in mortality rate due to increased concentration and time duration. The management of termite using J. curcas should be encouraged due to its environmental friendliness and should also be incorporated into integrated pest management (IPM)
Antioxidant activity, phenolic compounds and colour of red wines treated with new fining agents
Get PDFNowadays the clarification and stabilization of red wines is generally done with conventional fining agents, like bentonite and activated coal, which pose a major challenge to environmental security and wastes management. This stimulated the use of many new techniques in order to discover alternative fining agents that don’t have negative influence on color, phenolic compounds and quality parameters. The aim of this research is to determine, how alternative fining agents, in different doses, affect antioxidant activity and colour parameters of \u27Cabernet Sauvignon\u27 red wines. Experimental material is from North-East Romania and was fined with mesoporous materials, bentonite and activated coal. Discriminant analysis classified \u27Cabernet Sauvignon\u27 wines according to the different fining agents based on total polyphenolic compounds and total antioxidant activity. Alternative fining agents, as mesoporous materials, have less impact on the colour and phenolic content of red wines in contrast to activated coal and bentonite treatments that can conduct to unsatisfying characteristics. Mesoporous materials are preferable and could be an exceptional adsorbent for polyphenolic compounds
