The use of Trichogramma Westwood (Hymenoptera: Trichogrammatidae) in biological control requires ... more The use of Trichogramma Westwood (Hymenoptera: Trichogrammatidae) in biological control requires a very large number of insects to be released within an area. The storage of host eggs in liquid nitrogen may represent an alternative method in the mass production of Trichogramma. In order to evaluate the efficacy of egg storage in liquid nitrogen, we examined the parasitism, development and reproduction of Trichogrammapretiosum Riley and Trichogrammaatopovirilia Oatman and Platner on eggs of Mythimnasequax Franclemont (Lepidoptera: Noctuidae) stored in liquid nitrogen for 0 (control), 30, 60, or 90 days. Females of each species reared on eggs stored were used to assess their reproductive capacity. The parasitism did not differ between control and cryopreserved treatments. Eggs stored for 60 days had the highest parasitism. The storage of M. sequax eggs in liquid nitrogen was an effective method for the mass production of Trichogramma species.
The small tomato borer Neoleucinodes elegantalis (Guenée) (Lepidoptera: Crambidae) is one of the ... more The small tomato borer Neoleucinodes elegantalis (Guenée) (Lepidoptera: Crambidae) is one of the major pests of solanaceous in Central and South America. Little is known about the role of temperature on the biological traits of this species. Development time of the immature stages and longevity and reproduction of adults of N. elegantalis at constant temperatures (15, 20, 25, 27, and 30 ± 1°C) were determined when larvae were fed on fruits of the tomato hybrid "Paronset." Neoleucinodes elegantalis completed its life cycle at temperatures between 15°C and 27°C, indicating that it can remain active throughout the year in the subtropical region of Brazil. The temperature threshold (T t) was 8.8°C for the egg stage and 7.7°C for the larval and pupal stages. The small tomato borer required 588.2 degrees-day for its full development. At 30°C, the eggs were infertile, indicating that temperatures above 27°C are deleterious to the fertilization/embryonic development of the studied...
Aphid colonies were established on one second-node leaflet of young broad bean plants and subleth... more Aphid colonies were established on one second-node leaflet of young broad bean plants and sublethal treatments of 14C-labelled phorate were applied to the adjacent leaflets. After 3 days, the amounts of toxic and non-toxic 14C-labelled compounds in the aphids, their honeydew and the untreated foliage were determined. There were no significant differences between the amounts in leaves at the same level on the plant when infested and aphid-free plants were compared, but the aphids and their honey-dew contained two and 23 times as much of the toxic and non-toxic 14C-compounds, respectively, found in the host leaflets. Following translocation to aphids on leaves above or below treated leaflets, the aphid colonies again contained more labelled compounds than the host-plant leaves. The movement of non-toxic compounds into the roots was reduced when the aphid colonies were situated on foliage between the site of treatment and the roots. More of the toxic and the non-toxic fractions were translocated downwards from the third to the second leaf than in the reverse direction.
O consumo e a utilização do alimento em lagartas de Pseudaletia sequax Franclemont sadias e paras... more O consumo e a utilização do alimento em lagartas de Pseudaletia sequax Franclemont sadias e parasitadas por Glyptapanteles muesebecki (Blanchard) (Hymenoptera: Braconidae) foram avaliados em laboratório, utilizando-se folhas de capim quicuio (Pennisetumclandestinum). Lagartas parasitadas consumiram significativamente menos alimento que lagartas não parasitadas, embora o parasitismo tenha provocado um aumento na duração total do período de alimentação. Lagartas parasitadas que passaram por sete ínstares, pelo fato de terem dado origem a um número maior de parasitóides, consumiram significativamente mais alimento que lagartas com seis ínstares. Os valores encontrados para a taxa de consumo relativo (RCR), taxa metabólica relativa (RMR) e digestibilidade aproximada (AD) foram superiores em lagartas parasitadas. Por outro lado, a taxa de crescimento relativo (RGR) e os valores de eficiência de conversão do alimento ingerido (ECI) e digerido (ECD) em biomassa foram mais altos em lagartas...
A capacidade reprodutiva de Glyptapanteles muesebecki (Blanchard) (Hymenoptera: Braconidae) foi e... more A capacidade reprodutiva de Glyptapanteles muesebecki (Blanchard) (Hymenoptera: Braconidae) foi estudada em laboratório (20 ± 1ºC; 12 horas de fotofase) utilizando-se como hospedeiros lagartas de segundo ínstar de Pseudaletia sequax Franclemont (Lepidoptera: Noctuidae). Fêmeas expostas a cinco lagartas por dia viveram em média 8,4 dias, enquanto que fêmeas criadas na ausência de hospedeiro viveram em média 20,6 dias. Fêmeas de G. muesebecki parasitaram em média 20,8 lagartas durante a vida, produzindo um total de 666,8 descendentes. O parasitismo diário foi de 3,6 hospedeiros por fêmea no primeiro dia após a emergência e manteve-se acima de dois hospedeiros por fêmea até o oitavo dia. Até cinco lagartas foram parasitadas por fêmea em um período de 24 horas.
The developmental time of Glyptapanteles muesebecki (Blanchard) parasitizing the armyworm Pseudal... more The developmental time of Glyptapanteles muesebecki (Blanchard) parasitizing the armyworm Pseudaletia sequax Franclemont, and the number of pupae/host were determined at six constant temperatures ranging from 14° to 30°C. The egg + larval stages lasted from 17.8 days at 26° and 29°C to 56.4 days at 14°C, while the pupal stage ranged from 6.4 days at 29°C to 34.5 days at 14°C. G. muesebecki required 291.9 degree-days (DD) above the lower threshold of 8.9°C to complete the egg + larval development, while the pupae required 107.0 DD above 11.1°C. Development from egg to adult was completed after 397.4 DD above the lower threshold of 9.6°C. The number of pupae/host was not significantly different between 18°° and 26°C, and ranged from 86.9 at 22°C to 92.1 at 18°C. At the lower (14°°C) and upper (29°C) threshold temperatures, this number was significantly lower, averaging 27.6 and 19.8 pupae/host, respectively. Moreover, at 14° and 29°C the proportion of parasitized caterpillars was sign...
Telenomus cyamophylax Polaszek, n. sp. is described from the eggs of the soybean pest velvetbean ... more Telenomus cyamophylax Polaszek, n. sp. is described from the eggs of the soybean pest velvetbean Anticarsia gemmatalis (Hübner) (Lepidoptera: Noctuidae) caterpillar. This new species belongs to the californicus-group sensu Johnson, 1984. Biological data, including one alternative host, are given.
Temperature is considered to be an important abiotic factor influencing insect reproduction. Desp... more Temperature is considered to be an important abiotic factor influencing insect reproduction. Despite the importance of Plutella xylostella L. (Lepidoptera: Plutellidae) as a pest of brassicaceous crops worldwide, the effects of temperature on its reproduction are not well understood. We evaluated the effect of constant temperatures ranging from 10 to 32.5°C on the reproduction of P. xylostella and developed an oviposition model for the species. The model combined temperature-dependent parameters of total fecundity, age-specific oviposition rate and age-specific survival. Additionally, we modelled population growth as a function of temperature. The estimated parameters allowed us to discuss the possible consequences of global warming on P. xylostella distribution. Temperature affected the length of pre-oviposition after adult emergence, oviposition period, longevity, total fecundity and egg viability. The model predicted that both daily egg production and length of oviposition period...
Adults of Trissolcus basalis and Telenomus podisi were stored either at 15 or 18°C after their im... more Adults of Trissolcus basalis and Telenomus podisi were stored either at 15 or 18°C after their immature development had been completed at 18 or 25°C. Longevity of the parasitoids in the storage temperatures was evaluated, as well as fecundity and longevity following their return to 25°C after different periods in reproductive diapause. Temperature during immature development influenced female longevity and highest mean longevity was obtained for females that developed to the adult stage at 25°C and then were stored at 15°C (ca. 13 months for T. basalis and 10 months for Te. podisi). For adults of T. basalis that developed at 25°C, storage periods of 120 or 180 days at 15 or 18°C did not affect fecundity. The fecundity of T. basalis females that developed at 18°C and were stored for 120 days at 15 or 18°C was not affected; however, after remaining for 180 days, fecundity was reduced in ca. 30 and 50%, respectively. Storage of Te. podisi adults at 15 or 18°C significantly reduced fecundity. It is concluded that adults of T. basalis can be stored in the adult stage at 15 or 18°C between two soybean crop seasons for mass production purposes, aiming the biological control of stink bugs.
... The estimated survival curves by KaplanMeier's method showed that the survival of males... more ... The estimated survival curves by KaplanMeier's method showed that the survival of males (χ2 = 78.56, df = 5,90, P < 0.01) and females (χ2 ... Chalcoff, VR, Aizen, MA & Galetto, L. (2006) Nectar concentration and composition of 26 species from the temperate forest of South Africa ...
The use of Trichogramma Westwood (Hymenoptera: Trichogrammatidae) in biological control requires ... more The use of Trichogramma Westwood (Hymenoptera: Trichogrammatidae) in biological control requires a very large number of insects to be released within an area. The storage of host eggs in liquid nitrogen may represent an alternative method in the mass production of Trichogramma. In order to evaluate the efficacy of egg storage in liquid nitrogen, we examined the parasitism, development and reproduction of Trichogrammapretiosum Riley and Trichogrammaatopovirilia Oatman and Platner on eggs of Mythimnasequax Franclemont (Lepidoptera: Noctuidae) stored in liquid nitrogen for 0 (control), 30, 60, or 90 days. Females of each species reared on eggs stored were used to assess their reproductive capacity. The parasitism did not differ between control and cryopreserved treatments. Eggs stored for 60 days had the highest parasitism. The storage of M. sequax eggs in liquid nitrogen was an effective method for the mass production of Trichogramma species.
The small tomato borer Neoleucinodes elegantalis (Guenée) (Lepidoptera: Crambidae) is one of the ... more The small tomato borer Neoleucinodes elegantalis (Guenée) (Lepidoptera: Crambidae) is one of the major pests of solanaceous in Central and South America. Little is known about the role of temperature on the biological traits of this species. Development time of the immature stages and longevity and reproduction of adults of N. elegantalis at constant temperatures (15, 20, 25, 27, and 30 ± 1°C) were determined when larvae were fed on fruits of the tomato hybrid "Paronset." Neoleucinodes elegantalis completed its life cycle at temperatures between 15°C and 27°C, indicating that it can remain active throughout the year in the subtropical region of Brazil. The temperature threshold (T t) was 8.8°C for the egg stage and 7.7°C for the larval and pupal stages. The small tomato borer required 588.2 degrees-day for its full development. At 30°C, the eggs were infertile, indicating that temperatures above 27°C are deleterious to the fertilization/embryonic development of the studied...
Aphid colonies were established on one second-node leaflet of young broad bean plants and subleth... more Aphid colonies were established on one second-node leaflet of young broad bean plants and sublethal treatments of 14C-labelled phorate were applied to the adjacent leaflets. After 3 days, the amounts of toxic and non-toxic 14C-labelled compounds in the aphids, their honeydew and the untreated foliage were determined. There were no significant differences between the amounts in leaves at the same level on the plant when infested and aphid-free plants were compared, but the aphids and their honey-dew contained two and 23 times as much of the toxic and non-toxic 14C-compounds, respectively, found in the host leaflets. Following translocation to aphids on leaves above or below treated leaflets, the aphid colonies again contained more labelled compounds than the host-plant leaves. The movement of non-toxic compounds into the roots was reduced when the aphid colonies were situated on foliage between the site of treatment and the roots. More of the toxic and the non-toxic fractions were translocated downwards from the third to the second leaf than in the reverse direction.
O consumo e a utilização do alimento em lagartas de Pseudaletia sequax Franclemont sadias e paras... more O consumo e a utilização do alimento em lagartas de Pseudaletia sequax Franclemont sadias e parasitadas por Glyptapanteles muesebecki (Blanchard) (Hymenoptera: Braconidae) foram avaliados em laboratório, utilizando-se folhas de capim quicuio (Pennisetumclandestinum). Lagartas parasitadas consumiram significativamente menos alimento que lagartas não parasitadas, embora o parasitismo tenha provocado um aumento na duração total do período de alimentação. Lagartas parasitadas que passaram por sete ínstares, pelo fato de terem dado origem a um número maior de parasitóides, consumiram significativamente mais alimento que lagartas com seis ínstares. Os valores encontrados para a taxa de consumo relativo (RCR), taxa metabólica relativa (RMR) e digestibilidade aproximada (AD) foram superiores em lagartas parasitadas. Por outro lado, a taxa de crescimento relativo (RGR) e os valores de eficiência de conversão do alimento ingerido (ECI) e digerido (ECD) em biomassa foram mais altos em lagartas...
A capacidade reprodutiva de Glyptapanteles muesebecki (Blanchard) (Hymenoptera: Braconidae) foi e... more A capacidade reprodutiva de Glyptapanteles muesebecki (Blanchard) (Hymenoptera: Braconidae) foi estudada em laboratório (20 ± 1ºC; 12 horas de fotofase) utilizando-se como hospedeiros lagartas de segundo ínstar de Pseudaletia sequax Franclemont (Lepidoptera: Noctuidae). Fêmeas expostas a cinco lagartas por dia viveram em média 8,4 dias, enquanto que fêmeas criadas na ausência de hospedeiro viveram em média 20,6 dias. Fêmeas de G. muesebecki parasitaram em média 20,8 lagartas durante a vida, produzindo um total de 666,8 descendentes. O parasitismo diário foi de 3,6 hospedeiros por fêmea no primeiro dia após a emergência e manteve-se acima de dois hospedeiros por fêmea até o oitavo dia. Até cinco lagartas foram parasitadas por fêmea em um período de 24 horas.
The developmental time of Glyptapanteles muesebecki (Blanchard) parasitizing the armyworm Pseudal... more The developmental time of Glyptapanteles muesebecki (Blanchard) parasitizing the armyworm Pseudaletia sequax Franclemont, and the number of pupae/host were determined at six constant temperatures ranging from 14° to 30°C. The egg + larval stages lasted from 17.8 days at 26° and 29°C to 56.4 days at 14°C, while the pupal stage ranged from 6.4 days at 29°C to 34.5 days at 14°C. G. muesebecki required 291.9 degree-days (DD) above the lower threshold of 8.9°C to complete the egg + larval development, while the pupae required 107.0 DD above 11.1°C. Development from egg to adult was completed after 397.4 DD above the lower threshold of 9.6°C. The number of pupae/host was not significantly different between 18°° and 26°C, and ranged from 86.9 at 22°C to 92.1 at 18°C. At the lower (14°°C) and upper (29°C) threshold temperatures, this number was significantly lower, averaging 27.6 and 19.8 pupae/host, respectively. Moreover, at 14° and 29°C the proportion of parasitized caterpillars was sign...
Telenomus cyamophylax Polaszek, n. sp. is described from the eggs of the soybean pest velvetbean ... more Telenomus cyamophylax Polaszek, n. sp. is described from the eggs of the soybean pest velvetbean Anticarsia gemmatalis (Hübner) (Lepidoptera: Noctuidae) caterpillar. This new species belongs to the californicus-group sensu Johnson, 1984. Biological data, including one alternative host, are given.
Temperature is considered to be an important abiotic factor influencing insect reproduction. Desp... more Temperature is considered to be an important abiotic factor influencing insect reproduction. Despite the importance of Plutella xylostella L. (Lepidoptera: Plutellidae) as a pest of brassicaceous crops worldwide, the effects of temperature on its reproduction are not well understood. We evaluated the effect of constant temperatures ranging from 10 to 32.5°C on the reproduction of P. xylostella and developed an oviposition model for the species. The model combined temperature-dependent parameters of total fecundity, age-specific oviposition rate and age-specific survival. Additionally, we modelled population growth as a function of temperature. The estimated parameters allowed us to discuss the possible consequences of global warming on P. xylostella distribution. Temperature affected the length of pre-oviposition after adult emergence, oviposition period, longevity, total fecundity and egg viability. The model predicted that both daily egg production and length of oviposition period...
Adults of Trissolcus basalis and Telenomus podisi were stored either at 15 or 18°C after their im... more Adults of Trissolcus basalis and Telenomus podisi were stored either at 15 or 18°C after their immature development had been completed at 18 or 25°C. Longevity of the parasitoids in the storage temperatures was evaluated, as well as fecundity and longevity following their return to 25°C after different periods in reproductive diapause. Temperature during immature development influenced female longevity and highest mean longevity was obtained for females that developed to the adult stage at 25°C and then were stored at 15°C (ca. 13 months for T. basalis and 10 months for Te. podisi). For adults of T. basalis that developed at 25°C, storage periods of 120 or 180 days at 15 or 18°C did not affect fecundity. The fecundity of T. basalis females that developed at 18°C and were stored for 120 days at 15 or 18°C was not affected; however, after remaining for 180 days, fecundity was reduced in ca. 30 and 50%, respectively. Storage of Te. podisi adults at 15 or 18°C significantly reduced fecundity. It is concluded that adults of T. basalis can be stored in the adult stage at 15 or 18°C between two soybean crop seasons for mass production purposes, aiming the biological control of stink bugs.
... The estimated survival curves by KaplanMeier's method showed that the survival of males... more ... The estimated survival curves by KaplanMeier's method showed that the survival of males (χ2 = 78.56, df = 5,90, P < 0.01) and females (χ2 ... Chalcoff, VR, Aizen, MA & Galetto, L. (2006) Nectar concentration and composition of 26 species from the temperate forest of South Africa ...
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