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Hsin Chi - One of the best experts on this subject based on the ideXlab platform.
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demography and population projection of aphis fabae hemiptera aphididae with additional comments on Life Table research criteria
Journal of Economic Entomology, 2015Co-Authors: Izzet Akca, Tamer Ayvaz, Eda Yazici, Cecil L Smith, Hsin ChiAbstract:We collected developmental, survival, and reproduction data for Aphis fabae Scopoli (Hemiptera: Aphididae) reared on faba bean, Vicia faba L. 'Sevilla' at four constant temperatures (15, 20, 25, and 30°C), 70% relative humidity, and a photoperiod of 16:8 (L:D) h. The highest intrinsic rate of increase (r = 0.4347 d(-1)) and finite rate (λ = 1.5445 d(-1)) were observed at 25°C. The population projection based on the age-stage, two-sex Life Table quantitatively revealed the growth potential and stage structure of the aphid. We have included the following suggestions to aid researchers in Life Table studies: 1) The bootstrap method should be used to estimate the variance and SEs of developmental time, survival rate, fecundity, and population parameters. 2) The required number of bootstraps is dependent on the Life Table data--the higher the variation among individuals, the higher the number of bootstraps should be. In most cases, we suggest that 100,000 bootstraps should be used to obtain a sTable estimate of variance and SEs. 3) Computer projection based on the age-stage, two-sex Life Table should be used to reveal the stage structure during population growth. 4) We used a simple equation based on the total fecundity, survival rate to adult stage, and first reproductive age to detect possible errors in Life Table parameters. 5) To assist readers in comprehending results, Life Table studies should include the cohort size, preadult survival rate, number of emerged female adults, mean fecundity, survival and fecundity curves, and population parameters.
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a comparison of artificial diet and hybrid sweet corn for the rearing of helicoverpa armigera hubner lepidoptera noctuidae based on Life Table characteristics
Environmental Entomology, 2012Co-Authors: Ratna K Jha, Hsin Chi, Li Cheng TangAbstract:The demographic characteristics of Helicoverpa armigera (Hubner) reared on hybrid sweet corn (Zea mays L. variety saccharata) (hybrid super sweet corn KY bright jean) and on an artificial diet were compared by using the age-stage, two-sex Life Table. Because the hatch rate of eggs varies with maternal age, age-specific fecundity was calculated based on the numbers of hatched eggs to reveal the biological characteristics of H. armigera accurately. The intrinsic rate of increase (r), finite rate (λ) and mean generation time (T) of H. armigera were 0.0853 d(-1), 1.0890 d(-1), and 46.6 d, respectively, on Z. mays and 0.1015 d(-1), 1.1068 d(-1), and 46.3 d, respectively, on the artificial diet. There were significant differences in the intrinsic rate of increase and finite rate between two treatments. The age-stage Life expectancy and reproductive value also were calculated. The relationships among the net reproductive rate, the mean female fecundity, the number of emerged females, and the total number of individuals used in the Life Table study are consistent with theoretical expectations. We recommend the age-stage, two-sex Life Table for use in insect demographic studies to incorporate both sexes and the variation in developmental rate among individuals and to obtain accurate population parameters. The artificial diet is more suiTable for the mass rearing of H. armigera.
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Life Table of chrysomya megacephala fabricius diptera calliphoridae
Acta Oecologica-international Journal of Ecology, 2005Co-Authors: Refaat M Gabre, Fatma K Adham, Hsin ChiAbstract:The Life history of the oriental latrine fly, Chrysomya megacephala (Fabricius), was studied at 26 °C in the laboratory. The raw data were analyzed based on the age‐stage, two-sex Life Table, in order to take both sexes and the variable developmental rate among individuals and between sexes into consideration. The intrinsic rate of increase (r), the finite rate of increase (k), the net reproduction rate (R0) and the mean generation time (T )o fC. megacephala were 0.2182, 1.2438 d ‐1 , 91.7 offspring/individual and 20.7 days, respectively. The Life expectancy of a newborn egg is 32 days. The maximum reproductive value of females is on the 19th day, which coincides with the total pre-oviposition period counted from birth. The two-sex Life Table analysis gives a comprehensive description of the stage differentiation of C. megacephala. © 2005 Elsevier SAS. All rights reserved.
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two sex Life Table and predation rate of propylaea japonica thunberg coleoptera coccinellidae fed on myzus persicae sulzer homoptera aphididae
Environmental Entomology, 2003Co-Authors: Hsin Chi, Tachi YangAbstract:The Life history data of the predator Propylaea japonica Thunberg at 25°C fed on Myzus persicae (Sulzer) were collected in the laboratory. To take both sexes and the variable developmental rate among individuals into consideration, the raw data were analyzed based on the age-stage, two-sex Life Table. The intrinsic rate of increase for P. japonica is 0.1133 d−1. The net reproductive rate is 67.6 offspring and the mean generation time is 37.7 days. To incorporate the age-stage variability of the predation rate with the two-sex Life Table, the daily predation rate of individual P. japonica of both sexes was collected for each predatory stage. The net predation rate for P. japonica is 1199.5 aphids.
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Periodic Mass Rearing and Harvesting Based on the Theories of Both the Age-Specific Life Table and the Age-Stage, Two-Sex Life Table
Environmental Entomology, 1994Co-Authors: Hsin ChiAbstract:Periodic mass rearing and harvesting of specific Life stages are analyzed based on the theories of both the age-specific Life Table and the age-stage, two-sex Life Table. Formulae for the calculations of the optimal discard age and harvest rate are derived. For practical applications, the use of thermal summation to manipulate the developmental time of specific Life stage is suggested. The model is demonstrated using Life Table data of Ostrinia furnacalis (Guenee).
Mateus Chediak - One of the best experts on this subject based on the ideXlab platform.
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Life Table determination of thermal requirements of the tomato borer tuta absoluta
Journal of Pest Science, 2016Co-Authors: Julio Claudio Martins, Marcelo Coutinho Picanco, R N C Guedes, Leandro Bacci, P A Santana, Dalton De Oliveira Ferreira, Mateus ChediakAbstract:Temperature is one of the main factors affecting insect populations. The models used for studying the effect of temperature on insects are usually based on insect developmental rates. However, Life Table parameters such as the (intrinsic) population rate of increase (rm), which reflect the overall effect of temperature on the development, reproduction, and survival of the insect, should also be considered. The leaf miner Tuta absoluta (Lepidoptera: Gelechiidae) is an invasive tomato pest across several regions of the world with its range currently expanding because of its spread into the Middle East and Asia. Thus, this study aimed to assess the impact of temperature on T. absoluta and to determine the thermal requirements for this pest based on Life Table parameters. For this purpose, bioassays of the development and reproduction of T. absoluta under constant temperatures (17, 22, 26, 28, 30, and 33 °C) were performed. The thermal requirements of T. absoluta were assessed from rm. We found that the immature mortality of T. absoluta was lowest at 28 and 30 °C and highest at 17 °C. The optimum temperature for T. absoluta was 30 °C with upper and lower developmental thresholds of 34.6 and 14 °C, respectively. These thermal requirements were different from those that can be estimated from the rate of insect development. The results of this study would be helpful toward developing phenological, spatial, and temporal distribution models for T. absoluta and toward determining optimal management strategies for this pest species.
R N C Guedes - One of the best experts on this subject based on the ideXlab platform.
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Life Table determination of thermal requirements of the tomato borer tuta absoluta
Journal of Pest Science, 2016Co-Authors: Julio Claudio Martins, Marcelo Coutinho Picanco, R N C Guedes, Leandro Bacci, P A Santana, Dalton De Oliveira Ferreira, Mateus ChediakAbstract:Temperature is one of the main factors affecting insect populations. The models used for studying the effect of temperature on insects are usually based on insect developmental rates. However, Life Table parameters such as the (intrinsic) population rate of increase (rm), which reflect the overall effect of temperature on the development, reproduction, and survival of the insect, should also be considered. The leaf miner Tuta absoluta (Lepidoptera: Gelechiidae) is an invasive tomato pest across several regions of the world with its range currently expanding because of its spread into the Middle East and Asia. Thus, this study aimed to assess the impact of temperature on T. absoluta and to determine the thermal requirements for this pest based on Life Table parameters. For this purpose, bioassays of the development and reproduction of T. absoluta under constant temperatures (17, 22, 26, 28, 30, and 33 °C) were performed. The thermal requirements of T. absoluta were assessed from rm. We found that the immature mortality of T. absoluta was lowest at 28 and 30 °C and highest at 17 °C. The optimum temperature for T. absoluta was 30 °C with upper and lower developmental thresholds of 34.6 and 14 °C, respectively. These thermal requirements were different from those that can be estimated from the rate of insect development. The results of this study would be helpful toward developing phenological, spatial, and temporal distribution models for T. absoluta and toward determining optimal management strategies for this pest species.
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ecological Life Table of tuta absoluta meyrick lepidoptera gelechiidae
Biocontrol Science and Technology, 1998Co-Authors: Moacyr Mascarenhas Motta Miranda, José Cola Zanuncio, Marcelo Coutinho Picanco, R N C GuedesAbstract:An ecological Life Table was constructed, aiming to determine the critical stages and key mortality factors of Tuta absoluta (Lepidoptera: Gelechiidae). The total population mortality of this tomato leafminer was 92.3%. During the egg stage the mortality was 58.7%, mainly due to egg inviability. A total of 8.6% egg parasitism by Trichogramma pretiosum (Riley) (Hymenoptera: Trichogrammatidae) and 5.0% egg predation by Xylocoris sp. (Heteroptera: Anthocoridae), Cycloneda sanguinea (L.) (Coleoptera: Coccinellidae) and members of the family Phlaeothripidae (Thysanoptera) was observed. The mortality of the larval stage was 33.0%. This was considered to be the critical stage as it showed the highest apparent mortality (79.8%). Larval parasitism was low (0.1%), and was only found with Goniozus nigrifemur Ashmead (Hymenoptera: Bethylidae). Predators were responsible for 79.4% of larval mortality. Therefore, their attraction to and maintenance in the target area are important management tactics to be considered fo...
Marcelo Coutinho Picanco - One of the best experts on this subject based on the ideXlab platform.
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Life Table determination of thermal requirements of the tomato borer tuta absoluta
Journal of Pest Science, 2016Co-Authors: Julio Claudio Martins, Marcelo Coutinho Picanco, R N C Guedes, Leandro Bacci, P A Santana, Dalton De Oliveira Ferreira, Mateus ChediakAbstract:Temperature is one of the main factors affecting insect populations. The models used for studying the effect of temperature on insects are usually based on insect developmental rates. However, Life Table parameters such as the (intrinsic) population rate of increase (rm), which reflect the overall effect of temperature on the development, reproduction, and survival of the insect, should also be considered. The leaf miner Tuta absoluta (Lepidoptera: Gelechiidae) is an invasive tomato pest across several regions of the world with its range currently expanding because of its spread into the Middle East and Asia. Thus, this study aimed to assess the impact of temperature on T. absoluta and to determine the thermal requirements for this pest based on Life Table parameters. For this purpose, bioassays of the development and reproduction of T. absoluta under constant temperatures (17, 22, 26, 28, 30, and 33 °C) were performed. The thermal requirements of T. absoluta were assessed from rm. We found that the immature mortality of T. absoluta was lowest at 28 and 30 °C and highest at 17 °C. The optimum temperature for T. absoluta was 30 °C with upper and lower developmental thresholds of 34.6 and 14 °C, respectively. These thermal requirements were different from those that can be estimated from the rate of insect development. The results of this study would be helpful toward developing phenological, spatial, and temporal distribution models for T. absoluta and toward determining optimal management strategies for this pest species.
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ecological Life Table of tuta absoluta meyrick lepidoptera gelechiidae
Biocontrol Science and Technology, 1998Co-Authors: Moacyr Mascarenhas Motta Miranda, José Cola Zanuncio, Marcelo Coutinho Picanco, R N C GuedesAbstract:An ecological Life Table was constructed, aiming to determine the critical stages and key mortality factors of Tuta absoluta (Lepidoptera: Gelechiidae). The total population mortality of this tomato leafminer was 92.3%. During the egg stage the mortality was 58.7%, mainly due to egg inviability. A total of 8.6% egg parasitism by Trichogramma pretiosum (Riley) (Hymenoptera: Trichogrammatidae) and 5.0% egg predation by Xylocoris sp. (Heteroptera: Anthocoridae), Cycloneda sanguinea (L.) (Coleoptera: Coccinellidae) and members of the family Phlaeothripidae (Thysanoptera) was observed. The mortality of the larval stage was 33.0%. This was considered to be the critical stage as it showed the highest apparent mortality (79.8%). Larval parasitism was low (0.1%), and was only found with Goniozus nigrifemur Ashmead (Hymenoptera: Bethylidae). Predators were responsible for 79.4% of larval mortality. Therefore, their attraction to and maintenance in the target area are important management tactics to be considered fo...
Donald J Baird - One of the best experts on this subject based on the ideXlab platform.
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determining demographic effects of cypermethrin in the marine copepod acartia tonsa stage specific short tests versus Life Table tests
Archives of Environmental Contamination and Toxicology, 2002Co-Authors: Carlos Barata, Matias H Medina, Trevor C Telfer, Donald J BairdAbstract:Short-term lethal and sublethal responses of the calanoid copepod Acartia tonsa to cypermethrin were compared with Life-Table responses to assess whether or not it is necessary to use exposure periods longer than 5 days to estimate demographic responses to stress. More specifically, by limiting exposure periods to sensitive age classes (eggs, nauplii, copepodids, and adults) and including measurements on survival, egg production, and feeding rates, it was possible to derive a short test design of similar sensitivity and ecological relevance as full Life-Table tests. Short-term exposures to cypermethrin reduced copepodid's feeding rates at concentrations well below those affecting egg production rates and survival of eggs and adult stages. Lethal effects on naupliar stages occurred at lower concentrations than any other effect observed on eggs and adults. Life-Table sensitivities of the intrinsic rate of increase (r m) to cypermethrin were similar to those observed in short-term exposures. More specifically, exposure to cypermethrin impaired r m responses at concentrations (7.4 ng L−1) that also affected feeding and naupliar responses. Our results show that by quantifying and separating combined toxic effects on ecologically relevant individual Life-history traits, it is possible to develop toxicity test designs of similar ecological relevance yet that are less labor-intensive and costly than existing demographic tests.