Biology of telenomus pachycoris (Hymenoptera: Scelionidae), a parasitoid of eggs of pachycoris torridus (Hemiptera: Scutelleridae): the effects of egg age, exposure time, and temperature

Telenomus pachycoris (Johnson) (Hymenoptera: Scelionidae) is a parasitoid of eggs of Pachycoris torridus (Scopoli) (Hemiptera: Scutelleridae), a main pest of physic nut (Jatropha curcas L.; Euphorbiaceae). The objective of this work was to know the biology of T. pachycoris in P. torridus eggs under various conditions in order to develop a rearing technique for this parasitoid in the laboratory. We offered eggs of P. torridus to T. pachycoris during 4 exposition periods (6, 12, 18, and 24 h), as well as eggs of different ages (1 to 11 d), to evaluate, in both experiments, the number of parasitized eggs, duration of the egg-to-adult period, percentage of emergence, and sex ratio. We also evaluated the effect of constant temperatures (18, 20, 22, 25, 28, and 30 °C) and determined the duration of the egg-to-adult period, percentage of emergence, and sex ratio and estimated the thermal requirements and the number of generations per yr of T. pachycoris at each temperature. Parasitism of eggs was the highest at 12 h of exposure. Eggs up to 3 d old were the most parasitized, and the parasitism was zero on day 11. The duration of the egg-to-adult period was inversely proportional to temperature, ranging from 33.6 d at 18 °C to 9.8 d at 30 °C. The threshold temperature estimated for T. pachycoris was 12.9 °C, and the estimated thermal constant was 163.9 degree-days. The number of generations of T. pachycoris ranged from 11.3 to 38.1 per yr at 18 and 30 °C, respectively. The results may contribute to developing techniques for rearing T. pachycoris in the laboratory.Facultad de Ciencias Naturales y Muse

Biology of telenomus pachycoris (Hymenoptera: Scelionidae), a parasitoid of eggs of pachycoris torridus (Hemiptera: Scutelleridae): the effects of egg age, exposure time, and temperature

Telenomus pachycoris (Johnson) (Hymenoptera: Scelionidae) is a parasitoid of eggs of Pachycoris torridus (Scopoli) (Hemiptera: Scutelleridae), a main pest of physic nut (Jatropha curcas L.; Euphorbiaceae). The objective of this work was to know the biology of T. pachycoris in P. torridus eggs under various conditions in order to develop a rearing technique for this parasitoid in the laboratory. We offered eggs of P. torridus to T. pachycoris during 4 exposition periods (6, 12, 18, and 24 h), as well as eggs of different ages (1 to 11 d), to evaluate, in both experiments, the number of parasitized eggs, duration of the egg-to-adult period, percentage of emergence, and sex ratio. We also evaluated the effect of constant temperatures (18, 20, 22, 25, 28, and 30 °C) and determined the duration of the egg-to-adult period, percentage of emergence, and sex ratio and estimated the thermal requirements and the number of generations per yr of T. pachycoris at each temperature. Parasitism of eggs was the highest at 12 h of exposure. Eggs up to 3 d old were the most parasitized, and the parasitism was zero on day 11. The duration of the egg-to-adult period was inversely proportional to temperature, ranging from 33.6 d at 18 °C to 9.8 d at 30 °C. The threshold temperature estimated for T. pachycoris was 12.9 °C, and the estimated thermal constant was 163.9 degree-days. The number of generations of T. pachycoris ranged from 11.3 to 38.1 per yr at 18 and 30 °C, respectively. The results may contribute to developing techniques for rearing T. pachycoris in the laboratory.Facultad de Ciencias Naturales y Muse

Desenvolvimento e reprodução da mariposa-oriental em macieira e pessegueiro

The objective of this work was to evaluate the immature stages development and the reproductive parameters of Grapholita molesta adults reared on shoots and fruit of 'Vanguarda' peach, on fruit of 'Gala' and 'Fuji' apples, and on a diet formulated with corn meal. The experimental design was completely randomized. Each insect was considered one replicate; and for the biological parameters of adults study, each couple was considered a replicate. The fertility life table was calculated. The time for larvae development was shorter in peach shoots and fruits, in comparison with apple fruit and corn meal diets. There were no differences for larvae survival, in the comparison between diets. Based on fertility life table, 'Fuji' apple fruit are more appropriated to the G. molesta development than Gala ones. Peach shoots were more suited for insect development than fruit. The corn meal-based diet is suitable to rear G. molesta in laboratory. The evaluated diets affect survival rate, development and growth potential of G. molesta population.O objetivo deste trabalho foi avaliar o desenvolvimento de estágios imaturos e parâmetros reprodutivos de adultos de Grapholita molesta em dietas naturais, constituídas de ramos e frutos de pessegueiro 'Vanguarda', frutos de macieira 'Gala' e 'Fuji', e em dieta artificial à base de milho. O delineamento experimental foi inteiramente casualizado. Considerou-se cada inseto uma repetição e, no estudo dos parâmetros biológicos dos adultos, cada casal foi considerado uma repetição. Foi calculada a tabela de vida de fertilidade. O tempo para o desenvolvimento das lagartas foi menor em ramos e frutos do pessegueiro, em comparação a frutos de macieira e dieta à base de farinha de milho. Quanto à sobrevivência das larvas, não houve diferença entre as dietas. Com base na tabela de vida de fertilidade, os frutos da cultivar Fuji foram mais adequados ao desenvolvimento de G. molesta do que os da Gala. Os ramos de pessegueiro foram mais adequados ao desenvolvimento do inseto do que os frutos. A dieta à base de farinha de milho foi adequada para a criação dos insetos em laboratório. As dietas avaliadas afetam a taxa de sobrevivência, o desenvolvimento e o potencial de crescimento populacional de G. molesta

Biology of telenomus pachycoris (Hymenoptera: Scelionidae), a parasitoid of eggs of pachycoris torridus (Hemiptera: Scutelleridae): the effects of egg age, exposure time, and temperature

Telenomus pachycoris (Johnson) (Hymenoptera: Scelionidae) is a parasitoid of eggs of Pachycoris torridus (Scopoli) (Hemiptera: Scutelleridae), a main pest of physic nut (Jatropha curcas L.; Euphorbiaceae). The objective of this work was to know the biology of T. pachycoris in P. torridus eggs under various conditions in order to develop a rearing technique for this parasitoid in the laboratory. We offered eggs of P. torridus to T. pachycoris during 4 exposition periods (6, 12, 18, and 24 h), as well as eggs of different ages (1 to 11 d), to evaluate, in both experiments, the number of parasitized eggs, duration of the egg-to-adult period, percentage of emergence, and sex ratio. We also evaluated the effect of constant temperatures (18, 20, 22, 25, 28, and 30 °C) and determined the duration of the egg-to-adult period, percentage of emergence, and sex ratio and estimated the thermal requirements and the number of generations per yr of T. pachycoris at each temperature. Parasitism of eggs was the highest at 12 h of exposure. Eggs up to 3 d old were the most parasitized, and the parasitism was zero on day 11. The duration of the egg-to-adult period was inversely proportional to temperature, ranging from 33.6 d at 18 °C to 9.8 d at 30 °C. The threshold temperature estimated for T. pachycoris was 12.9 °C, and the estimated thermal constant was 163.9 degree-days. The number of generations of T. pachycoris ranged from 11.3 to 38.1 per yr at 18 and 30 °C, respectively. The results may contribute to developing techniques for rearing T. pachycoris in the laboratory.Facultad de Ciencias Naturales y Muse

Development and reproduction of the oriental fruit moth in apple and peaches

O objetivo deste trabalho foi avaliar o desenvolvimento de estágios imaturos e parâmetros reprodutivos de adultos de Grapholita molesta em dietas naturais, constituídas de ramos e frutos de pessegueiro 'Vanguarda', frutos de macieira 'Gala' e 'Fuji', e em dieta artificial à base de milho. O delineamento experimental foi inteiramente casualizado. Considerou-se cada inseto uma repetição e, no estudo dos parâmetros biológicos dos adultos, cada casal foi considerado uma repetição. Foi calculada a tabela de vida de fertilidade. O tempo para o desenvolvimento das lagartas foi menor em ramos e frutos do pessegueiro, em comparação a frutos de macieira e dieta à base de farinha de milho. Quanto à sobrevivência das larvas, não houve diferença entre as dietas. Com base na tabela de vida de fertilidade, os frutos da cultivar Fuji foram mais adequados ao desenvolvimento de G. molesta do que os da Gala. Os ramos de pessegueiro foram mais adequados ao desenvolvimento do inseto do que os frutos. A dieta à base de farinha de milho foi adequada para a criação dos insetos em laboratório. As dietas avaliadas afetam a taxa de sobrevivência, o desenvolvimento e o potencial de crescimento populacional de G. molesta.The objective of this work was to evaluate the immature stages development and the reproductive parameters of Grapholita molesta adults reared on shoots and fruit of 'Vanguarda' peach, on fruit of 'Gala' and 'Fuji' apples, and on a diet formulated with corn meal. The experimental design was completely randomized. Each insect was considered one replicate; and for the biological parameters of adults study, each couple was considered a replicate. The fertility life table was calculated. The time for larvae development was shorter in peach shoots and fruits, in comparison with apple fruit and corn meal diets. There were no differences for larvae survival, in the comparison between diets. Based on fertility life table, 'Fuji' apple fruit are more appropriated to the G. molesta development than Gala ones. Peach shoots were more suited for insect development than fruit. The corn meal-based diet is suitable to rear G. molesta in laboratory. The evaluated diets affect survival rate, development and growth potential of G. molesta population

Biology and Management of Pest Diabrotica Species in South America

The genus Diabrotica has over 400 described species, the majority of them neotropical. However, only three species of neotropical Diabrotica are considered agricultural pests: D. speciosa, D. balteata, and D. viridula. D. speciosa and D. balteata are polyphagous both as adults and during the larval stage. D. viridula are stenophagous during the larval stage, feeding essentially on maize roots, and polyphagous as adults. The larvae of the three species are pests on maize, but D. speciosa larvae also feed on potatoes and peanuts, while D. balteata larvae feed on beans and peanuts. None of these species express a winter/dry season egg diapause, displaying instead several continuous, latitude-mediated generations per year. This hinders the use of crop rotation as a management tool, although early planting can help in the temperate regions of the distribution of D. speciosa. The parasitoids of adults, Celatoria bosqi and Centistes gasseni, do not exert much control on Diabrotica populations, or show potential for inundative biocontrol plans. Management options are limited to insecticide applications and Bt genetically modified (GM) maize. Other techniques that show promise are products using Beauveria bassiana and Heterorhabditis bacteriophora, semiochemical attractants for monitoring purposes or as toxic baits, and plant resistance.Facultad de Ciencias Naturales y Muse

Population genomics of Drosophila suzukii reveal longitudinal population structure and signals of migrations in and out of the continental United States

Drosophila suzukii, or spotted-wing drosophila, is now an established pest in many parts of the world, causing significant damage to numerous fruit crop industries. Native to East Asia, D. suzukii infestations started in the United States (U.S.) a decade ago, occupying a wide range of climates. To better understand invasion ecology of this pest, knowledge of past migration events, population structure, and genetic diversity is needed. In this study, we sequenced whole genomes of 237 individual flies collected across the continental U.S., as well as several sites in Europe, Brazil, and Asia, to identify and analyze hundreds of thousands of genetic markers. We observed strong population structure between Western and Eastern U.S. populations, but no evidence of any population structure between different latitudes within the continental U.S., suggesting there is no broad-scale adaptations occurring in response to differences in winter climates. We detect admixture from Hawaii to the Western U.S. and from the Eastern U.S. to Europe, in agreement with previously identified introduction routes inferred from microsatellite analysis. We also detect potential signals of admixture from the Western U.S. back to Asia, which could have important implications for shipping and quarantine policies for exported agriculture. We anticipate this large genomic dataset will spur future research into the genomic adaptations underlying D. suzukii pest activity and development of novel control methods for this agricultural pes