Cotesia flavipes é uma vespa endoparasitóide introduzida no Brasil para controlar biologicamente o hospedeiro Diatraea saccharalis, conhecida como a broca da cana-de-açúcar. Estes insetos são criados há mais de trinta anos no Brasil em laboratórios de criação massal. Em épocas de boa produtividade de fêmeas nos laboratórios de criação massal os parasitóides são utilizados logo após a emergência. Porém, em alguns períodos do ano, a produção de insetos apresenta com a razão sexual desviada para machos então, os insetos são utilizados após 24 horas, para tentar garantir a cópula. O objetivo deste trabalho foi comparar a eficiência de C.flavipes de três idades (0, 24 e 48h) no parasitismo de D. saccharalis de 5° instar e com a densidade de 3 hospedeiros. Três hospedeiros foram oferecidos à fêmea parasitóide para que a mesma realizasse as posturas em um curto intervalo de tempo e com densidade fixa. Verificou-se que C. flavipes das três idades foram capazes de parasitar os 3 hospedeiros oferecidos para oviposição e também de gerar prole nos mesmos. Porém, os hospedeiros que receberam a primeira postura das vespas com 0, 24 e 48 de idade tiveram o maior tamanho de prole. Houve diferença no tamanho da prole para as 3ª lagartas parasitadas de 24 e 48 horas de idade enquanto as vespas de 0 h parasitaram, mas não geraram prole no hospedeiro D. saccharalis. Mas, quando comparou-se estatisticamente o a média das três idades o tamanho da prole foi igual. A razão sexual tambémfoi estatisticamente igual em todas idades e nas três posturas. Concluí-se que C. flavipes de 0, 24 e 48 horas de idade são igualmente eficientes no parasitismo de Diatraea saccharalis. / Cotesia flavipes is an endoparasitoid wasp introduced in Brazil to biologically control the host Diatraea saccharalis, commonly known as the sugar cane drill. These insects have been reared for more than thirty years in Brazil, in massal rearing creation laboratories. In times of good female productivity in massal rearing creation laboratories, the parasitoids are used immediately after emergence. Though, in certain periods of the year, insect production presents a sex ratio towards males, so the insects are used after 24 hours in order to guarantee copulation. The objective of this work was to compare the efficiency of C. flavipes of three ages (0, 24 and 48h) in the parasitism of 5th instar D. saccharalis with a density of three hosts. Three hosts were offered to a female parasitoid so that she would deposit eggs in a short time interval with a fixed density. The study verified that C. flavipes of all three ages was capable of parasitizing the three hosts offered for oviposition and also of generating offspring from them. Though, the host which received the wasps first deposit with 0, 24 and 48h of age, had the largest number of offspring. There was a difference in the number of offspring for the third parasitized caterpillar for wasps? aged 24 and 48 h, while newly emerged (0h) wasps parasitized the host D. saccharalis without generating offspring. Although, when the means for the three ages were compared statistically, offspring sizes were equal. Sexual bias was also statistically equal in all three ages and in the three deposits. We conclude that C. flavipes aged 0, 24 and 48 h are equally efficient in the parasitism of D. saccharalis.

lt;p align="justify"gt; O controle biológico utiliza inimigos naturais para reduzir infestação de pragas. A Cotesia flavipes (Hymenoptera: Braconidae) é uma vespa parasitóide que combate Diatraea saccharalis (Lepidoptera: Pyralidae), praga que causa grandes perdas na produção de cana-de-açúcar (Saccharum officinarum L.). Analisou-se o efeito da temperatura sobre razão sexual do parasitóide C. flavipes em lagartas D. saccharalis. Inoculou-se lagartas com 14 dias de eclosão em temperaturas 21, 25, 30 e 40oC e fotoperíodo de 12 horas. Na temperatura de 25oC foi analisado o efeito da quantidade de alimento sobre as massas secas de machos e fêmeas de C. flavipes e a proporção sexual de C. flavipes sendo realizado um ensaio com quantidades crescentes de alimento (1,0; 1,5; 2,0; 2,5 e 3,0g) para lagarta D. saccharalis inoculada com o parasitóide C. flavipes. Para verificar a razão sexual entre machos e fêmeas de C. flavipes do insetário, 50 massas contendo casulos da vespa C. flavipes foram retiradas aleatoriamente de cinco lotes de diferentes inoculadores, contendo cada placa de Petri quatro lagartas parasitadas. Após a emergência e morte dos adultos de C. flavipes foi contada a quantidade de machos e de fêmeas. Os resultados obtidos mostraram que em relação à temperatura foi observado que a 30 e 40oC ocorreu 100% de mortalidade de D. saccharalis parasitadas. Na temperatura de 21 ± 0,9oC a razão sexual observada foi de 3:5 (machos: fêmeas) enquanto a 25 ± 1,2oC a foi de 2:5 (machos: fêmeas). A quantidade de dieta não apresentou relação com a massa seca total de C. flavipes não afetando, portanto, a proporção sexual. A razão sexual nas condições atuais de criação do parasitóide no insetário observada foi de 3:5 (macho: fêmea).lt;/pgt; / lt;p align="justify"gt; The biological control using natural enemies to reduce the pest infestation. The Cotesia flavipes (Hymenoptera: Braconidae) is a wasp that parasitoid fight Diatraea saccharalis (Lepidoptera: Pyralidae), pest that causes major losses in the production of sugar cane (Saccharum officinarum L.). Examined is the effect of temperature on sex ratio of the parasitoid Cotesia flavipes on caterpillars Diatraea saccharalis. Was inoculated with caterpillars hatch in 14 days of temperatures 21, 25, 30 and 40oC and photoperiod for 12 hours. At temperatures of 25°C was examined the effect of the quantity of food on the masses droughts of males and females of C. flavipes and the proportion of sexual C. flavipes being conducted a test with increasing amounts of food (1.0; 1.5; 2.0; 2.5 and 3.0 g) for caterpillar D. saccharalis inoculated with the parasitoid C. flavipes. To check the sex ratio between males and females of C. flavipes of insetário, 50 bodies containing the wasp cocoons C. flavipes were drawn randomly from five lots of different inoculadores, and each card Petri four inoculated caterpillars. After the emergence and death of adults of C. flavipes was counted the number of males and females. The results showed that in relation to temperature was observed that the 30 and 40oC was 100% mortality of D. saccharalis inoculated. The temperature of 21 ± 0.9°C the observed sex ratio was 3:5 (male: female) while 25 ± 1.2°C was the 2:5 (male: female). The amount of diet not submitted relationship with the total dry weight of C. flavipes not changing, so the proportion sexual. The sex ratio in the current conditions for the creation of parasitoid in insetário observed was 3:5 (male: female).lt;/pgt;

Cotesia flavipes é uma vespa endoparasitóide introduzida no Brasil para controlar biologicamente o hospedeiro Diatraea saccharalis, conhecida como a broca da cana-de-açúcar. Estes insetos são criados há mais de trinta anos no Brasil em laboratórios de criação massal. Em épocas de boa produtividade de fêmeas nos laboratórios de criação massal os parasitóides são utilizados logo após a emergência. Porém, em alguns períodos do ano, a produção de insetos apresenta com a razão sexual desviada para machos então, os insetos são utilizados após 24 horas, para tentar garantir a cópula. O objetivo deste trabalho foi comparar a eficiência de C.flavipes de três idades (0, 24 e 48h) no parasitismo de D. saccharalis de 5° instar e com a densidade de 3 hospedeiros. Três hospedeiros foram oferecidos à fêmea parasitóide para que a mesma realizasse as posturas em um curto intervalo de tempo e com densidade fixa. Verificou-se que C. flavipes das três idades foram capazes de parasitar os 3 hospedeiros oferecidos para oviposição e também de gerar prole nos mesmos. Porém, os hospedeiros que receberam a primeira postura das vespas com 0, 24 e 48 de idade tiveram o maior tamanho de prole. Houve diferença no tamanho da prole para as 3ª lagartas parasitadas de 24 e 48 horas de idade enquanto as vespas de 0 h parasitaram, mas não geraram prole no hospedeiro D. saccharalis. Mas, quando comparou-se estatisticamente o a média das três idades o tamanho da prole foi igual. A razão sexual tambémfoi estatisticamente igual em todas idades e nas três posturas. Concluí-se que C. flavipes de 0, 24 e 48 horas de idade são igualmente eficientes no parasitismo de Diatraea saccharalis. / Cotesia flavipes is an endoparasitoid wasp introduced in Brazil to biologically control the host Diatraea saccharalis, commonly known as the sugar cane drill. These insects have been reared for more than thirty years in Brazil, in massal rearing creation laboratories. In times of good female productivity in massal rearing creation laboratories, the parasitoids are used immediately after emergence. Though, in certain periods of the year, insect production presents a sex ratio towards males, so the insects are used after 24 hours in order to guarantee copulation. The objective of this work was to compare the efficiency of C. flavipes of three ages (0, 24 and 48h) in the parasitism of 5th instar D. saccharalis with a density of three hosts. Three hosts were offered to a female parasitoid so that she would deposit eggs in a short time interval with a fixed density. The study verified that C. flavipes of all three ages was capable of parasitizing the three hosts offered for oviposition and also of generating offspring from them. Though, the host which received the wasps first deposit with 0, 24 and 48h of age, had the largest number of offspring. There was a difference in the number of offspring for the third parasitized caterpillar for wasps? aged 24 and 48 h, while newly emerged (0h) wasps parasitized the host D. saccharalis without generating offspring. Although, when the means for the three ages were compared statistically, offspring sizes were equal. Sexual bias was also statistically equal in all three ages and in the three deposits. We conclude that C. flavipes aged 0, 24 and 48 h are equally efficient in the parasitism of D. saccharalis.

Made available in DSpace on 2014-06-11T19:28:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-09-10Bitstream added on 2014-06-13T18:57:45Z : No. of bitstreams: 1 camillo_mf_me_jabo.pdf: 459342 bytes, checksum: 91a470a114ea0b0b91c4435f01edec49 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Usina São Martinho / A broca da cana-de-açúcar Diatraea saccharalis (Fabricius, 1794), destaca-se como a principal praga da cultura da cana-de-açúcar e dependendo do nível de infestação, pode causar sérios prejuízos financeiros a produtores. O sucesso no seu controle depende de estudos comportamentais das variedades e avaliação de seu parasitismo, principalmente por Cotesia flavipes (Cameron, 1891). Assim o objetivo da presente pesquisa foi verificar a infestação e os danos causados por D. saccharalis e seu parasitismo por C. flavipes em duas idades de corte das plantas em variedades de cana-de-açúcar. O experimento foi conduzido na Usina Laguna, localizada no município de Batayporã no Estado do Mato Grosso do Sul. O delineamento experimental utilizado foi em parcelas subdivididas, com 5 variedades, RB86-7515, SP81-3250, RB85-5453, SP80-1842 e RB82-5211 duas idades de corte, cana planta e cana soca de segundo corte e 4 repetições, dispostas em blocos casualizados, aplicando as variedades nas parcelas e as idades de corte nas subparcelas. Foram avaliadas a porcentagem e intensidade de infestação, porcentagem de danos no colmo, população da broca por hectare e a porcentagem de parasitismo. Pelos resultados obtidos conclui-se que as variedades menos atacadas por D. saccharalis foram SP81-3250 e RB92-5211; a variedade mais atacada por D. saccharalis foi SP80-1842; as liberações de C. flavipes incrementaram o parasitismo na área; o aumento da porcentagem de parasitismo proporcionou redução na população da broca; e o parasitismo independe da idade de corte da cana-de-açúcar / In the culture of sugar cane, and all, there are pests that directly affect production. The sugarcane borer Diatraea saccharalis (Fabricius, 1794), stands out as the main and depending on the level of infestation, can cause serious financial losses to producers. The success in controlling this pest depends on behaviour studies of varieties and evaluation of their parasitism, mainly by Cotesia flavipes (Cameron, 1891). Thus the aim of this research was to verify the infestation and the damage caused by D. saccharalis and its parasitism by C. flavipes in two plant ages in varieties of sugar cane. The experiment was conducted at the Laguna Plant, located in Batayporã borough in Mato-Grosso-do-Sul state. The varieties used in the experiment were RB86-7515, SP81-3250, RB85-5453, SP80-1842 and RB82-5211 conducted in plots of 10 080 m2, repeated four times, adopting the split plot design, applying the varieties in the plots and subplots cutting ages. It was evaluated the rate and intensity of infestation, percentage of damage in the stem borer population per hectare and percentage parasitism. By the results it is concluded that varieties less attacked by D. saccharalis were SP81-3250 and RB92-5211, the variety most attacked by D. saccharalis was SP80-1842, an increase of the parasitism decreased the population of the drill, the release of C. flavipes increased the parasitism the area, and the parasitism is independent of the sugar cane cut age

A three-year field experiment was conducted to evaluate the tolerance and compensatory response of rice (Oryza sativa L.) to injury caused by the sugarcane borer, Diatraea saccharalis (F.). Two mechanisms of within-plant tolerance/compensation were observed. Stem injured plants produced ca. 0.69 more tillers than uninjured plants, while tillers with leaf and leaf sheath injury produced larger panicles, up to 39.5% and 21.0% heavier than uninjured tillers, when injury occurred at 3rd tiller stage and at panicle differentiation, respectively. A 2-year field cage experiment was conducted to determine the biological control potential of Cotesia flavipes (Cameron) against the sugarcane borer on rice. The effective search rate was 49 cm2 ground area (2.2 tillers) parasitoid-1 day-1. A cohortbased age-structured model was developed to simulate the population dynamics and economic value of the sugarcane borer and C. flavipes in rice, as affected by overwintering larval density, timing and rate of parasitoid aerial release, and year-to-year climate (temperature and rainfall). The results suggest C. flavipes was most effective when released during the 1st sugarcane borer generation. The maximum simulated economic benefit ($112.05 ha-1) was ca. 7.8% of that provided by insecticide-based control. The inability of C. flavipes to provide economic control in temperate-subtropical areas is due to its high rearing cost, a low effective search rate, a low maximum rate of parasitism per female, and both spatial and temporal asynchrony of parasitoid emergence with the larval hosts. The biocontrol capability of Trichogramma galloi Zucchi was also simulated. The maximum economic benefit provided by T. galloi was $1128.75 ha-1, ca. 79.0% of that provided by insecticide-based control. Theoretical analyses were conducted to estimate the effectiveness of augmentative releases, using data from previous studies of parasitism of lepidopteran pests by hymenopteran parasitoids with host and parasitoid density as factors. The maximum daily parasitism per female was highest for parasitoids that attack exposed larvae, followed by parasitoids that attack eggs, semi-exposed larvae, and concealed larvae. Simulation analyses were conducted to estimate the population dynamics and economic value of D. saccharalis, herein used as a model host, and each of 5 parasitoid categories (solitary parasitoids that attack eggs, exposed larvae, and semi-exposed larvae, gregarious parasitoids that attack eggs and concealed larvae) in rice, as affected by overwintering larval density, timing of parasitoid release, and year-to-year climate. Among the 13,500 simulations that were conducted, 480 (3.6%) provided a greater economic value than insecticide-based control. All 480 simulations were obtained using solitary parasitoids that attack exposed or semi-exposed larvae. Solitary egg parasitoids provided an average of 42.2% of the economic value provided by insecticide-based control when released 30 days after planting. Gregarious parasitoids that attack eggs or concealed larvae provided almost no positive economic benefit. For parasitoid species that do not overwinter successfully in areas where they are released or that exhibit temporal or spatial asynchrony with their host early in the spring, our results suggest augmentative biological control is only effective for solitary parasitoids that attack either exposed or semi-exposed larvae, with current rearing, shipping and release costs.

Made available in DSpace on 2014-06-11T19:31:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-12-21Bitstream added on 2014-06-13T20:02:57Z : No. of bitstreams: 1 viel_sr_dr_jabo.pdf: 828115 bytes, checksum: b974e906f04ebb44b4d4434000bd82f4 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Visando melhorias qualitativas na criação de Cotesia flavipes Cameron, 1891, realizaram-se testes com alimentação de adultos antes do parasitismo em Diatraea saccharalis Fabricius,1794, com 14 dietas: (2,5%; 5% e 10% sacarose; 2,5%; 5% e 10% sacarose + 2,5% lêvedo de cerveja; 2,5%; 5% e 10% mel; 2,5%; 5% e 10% mel + 2,5% lêvedo de cerveja; 2,5% lêvedo de cerveja; água) e testemunha. Avaliaramse: adultos emergidos, razão sexual, porcentagem de emergência, peso das massas de pupas e a longevidade nas gerações F1 e F2. O delineamento foi o inteiramente casualizado com 15 tratamentos e cinco repetições. As dietas a base de 5% de sacarose, 5 e 10% de mel aos adultos de C. flavipes podem proporcionar acréscimo considerável na longevidade dos parasitoides. O consumo de dietas artificiais por C. flavipes antes do parasitismo em D. saccharalis proporcionou melhorias qualitativas. O estudo visou ainda testar um protocolo de qualidade de C. flavipes, quanto à eficiência na busca pelo hospedeiro D. saccharalis. Foi usada uma arena de testes (copo plástico translúcido de 700 mL, com tampa). Lagartas de D. saccharalis foram colocadas em tolete de cana-de-açúcar de 13 cm, perfurado transversalmente e oferecidas ao parasitoide. Os tratamentos foram: (0, 6, 12, 18 e 24 horas de fotofase - L), (6, 12, 18 e 24 horas de disponibilidade do hospedeiro - H), (1, 2, 3, 4 e 5 lagartas por arena - T) e o orifício de entrada da lagarta na cana-de-açúcar (aberto - A ou fechado - F). Foram realizados os testes de Kolmogorov e a homogeneidade da variância foi analisada pelo teste de Bartlett, além das análises de agrupamento e de componentes principais. Foi criado um Índice de performance da qualidade (IPQ), que foi determinante na escolha do melhor tratamento. Foi proposto, o uso do tratamento: 6 horas de disponibilidade... / Aiming at qualitative improvements in the rearing of Cotesia flavipes, tests were carried out with adults feed before parasitism in Diatraea saccharalis, with 14 diets (2.5%, 5% and 10% sucrose, 2.5%, 5% and 10% sucrose + 2.5% brewer's yeast, 2.5%, 5% and 10% honey, 2.5%, 5% and 10% honey + 2.5% yeast, 2.5% yeast, water) and control. Were evaluated: emerging adults, sex ratio, percentage of emergency, mass weight of pupae, and longevity in F1 and F2 generations. The design was completely randomized with 15 treatments and five repetitions. The diets based on 5% sucrose, 5 and 10% honey to adults of C. flavipes, may provide considerable increase in longevity. Consumption of artificial diets by C. flavipes before parasitism in D. saccharalis provides quality improvements. The study also aimed to test a protocol for quality of C. flavipes, for efficiency in the search for host D. saccharalis. We used a testing arena (700 mL plastic cup with lid). Larvae of D. saccharalis were placed in 13 cm cutting canes, drilled across, and offered to the parasitoid. The treatments were: (0, 6, 12, 18 and 24 hours of photophase - L) (6, 12, 18 and 24 hours of availability of the host - H) (1, 2, 3, 4 and 5 larvae per arena - T) and the entrance hole of the larvae in sugar cane (open - A or closed - F). We performed the Kolmogorov´s test and the homogeneity of variance was analyzed by Bartlett's test. Were also carried out cluster analysis and principal components. It created an index of performance quality (IPQ). It is proposed the use of treatment 6 hours of availability, 0 hours of light, one larvae per arena, using the cutting cane with the hole closed, as quality protocol C. flavipes

Orientador: Sérgio Antonio de Bortoli / Coorientador: Nelson Wanderley Perioto / Banca: Enrico de Beni Arrigoni / Banca: Rogéria Inês Rosa Lara / Banca: Luis Garrigos Leite / Banca: Ricardo Antonio Polanczyk / Resumo: Visando melhorias qualitativas na criação de Cotesia flavipes Cameron, 1891, realizaram-se testes com alimentação de adultos antes do parasitismo em Diatraea saccharalis Fabricius,1794, com 14 dietas: (2,5%; 5% e 10% sacarose; 2,5%; 5% e 10% sacarose + 2,5% lêvedo de cerveja; 2,5%; 5% e 10% mel; 2,5%; 5% e 10% mel + 2,5% lêvedo de cerveja; 2,5% lêvedo de cerveja; água) e testemunha. Avaliaramse: adultos emergidos, razão sexual, porcentagem de emergência, peso das massas de pupas e a longevidade nas gerações F1 e F2. O delineamento foi o inteiramente casualizado com 15 tratamentos e cinco repetições. As dietas a base de 5% de sacarose, 5 e 10% de mel aos adultos de C. flavipes podem proporcionar acréscimo considerável na longevidade dos parasitoides. O consumo de dietas artificiais por C. flavipes antes do parasitismo em D. saccharalis proporcionou melhorias qualitativas. O estudo visou ainda testar um protocolo de qualidade de C. flavipes, quanto à eficiência na busca pelo hospedeiro D. saccharalis. Foi usada uma arena de testes (copo plástico translúcido de 700 mL, com tampa). Lagartas de D. saccharalis foram colocadas em tolete de cana-de-açúcar de 13 cm, perfurado transversalmente e oferecidas ao parasitoide. Os tratamentos foram: (0, 6, 12, 18 e 24 horas de fotofase - L), (6, 12, 18 e 24 horas de disponibilidade do hospedeiro - H), (1, 2, 3, 4 e 5 lagartas por arena - T) e o orifício de entrada da lagarta na cana-de-açúcar (aberto - A ou fechado - F). Foram realizados os testes de Kolmogorov e a homogeneidade da variância foi analisada pelo teste de Bartlett, além das análises de agrupamento e de componentes principais. Foi criado um Índice de performance da qualidade (IPQ), que foi determinante na escolha do melhor tratamento. Foi proposto, o uso do tratamento: 6 horas de disponibilidade... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Aiming at qualitative improvements in the rearing of Cotesia flavipes, tests were carried out with adults feed before parasitism in Diatraea saccharalis, with 14 diets (2.5%, 5% and 10% sucrose, 2.5%, 5% and 10% sucrose + 2.5% brewer's yeast, 2.5%, 5% and 10% honey, 2.5%, 5% and 10% honey + 2.5% yeast, 2.5% yeast, water) and control. Were evaluated: emerging adults, sex ratio, percentage of emergency, mass weight of pupae, and longevity in F1 and F2 generations. The design was completely randomized with 15 treatments and five repetitions. The diets based on 5% sucrose, 5 and 10% honey to adults of C. flavipes, may provide considerable increase in longevity. Consumption of artificial diets by C. flavipes before parasitism in D. saccharalis provides quality improvements. The study also aimed to test a protocol for quality of C. flavipes, for efficiency in the search for host D. saccharalis. We used a testing arena (700 mL plastic cup with lid). Larvae of D. saccharalis were placed in 13 cm cutting canes, drilled across, and offered to the parasitoid. The treatments were: (0, 6, 12, 18 and 24 hours of photophase - L) (6, 12, 18 and 24 hours of availability of the host - H) (1, 2, 3, 4 and 5 larvae per arena - T) and the entrance hole of the larvae in sugar cane (open - A or closed - F). We performed the Kolmogorov's test and the homogeneity of variance was analyzed by Bartlett's test. Were also carried out cluster analysis and principal components. It created an index of performance quality (IPQ). It is proposed the use of treatment 6 hours of availability, 0 hours of light, one larvae per arena, using the cutting cane with the hole closed, as quality protocol C. flavipes / Doutor

Submitted by (edna.saturno@ufrpe.br) on 2016-11-23T15:10:01Z No. of bitstreams: 1 Cinthia Conceicao Matias da Silva.pdf: 321146 bytes, checksum: e36e95044fe468bf9019c0b4774eac46 (MD5) / Made available in DSpace on 2016-11-23T15:10:01Z (GMT). No. of bitstreams: 1 Cinthia Conceicao Matias da Silva.pdf: 321146 bytes, checksum: e36e95044fe468bf9019c0b4774eac46 (MD5) Previous issue date: 2009-02-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This complex of sugarcane borers, in Brazil, comprises Diatraea saccharalis (Fabr.) and Diatraea flavipennella (Box) (Lepidoptera.: Crambidae). The control of borers, in Brazil, is the applied biological control using the larval endoparasitoid Cotesia flavipes (Cam.) (Hymenoptera: Braconidae). Recently, however, the biological control of D. flavipennella by the C. flavipes has been in discussion due to increasing occurrence of this borer species in the sugarcane fields across the northeast of Brazil. Thus, this study investigated the parasitism behavior of the parasitoid C. flavipes towards D. flavipennella side by side to D. saccharalis as well as determined its fertility life table parasitizing both hosts to clearify about this question. The parasitism behavior included free choice and host finding tests with and without visual cues, using arena in the laboratory. Larvae of D. saccharalis and D. flavipennella were exposed to 24h-old C. flavipes females, mated and fed. The free choice test consisted of an arena containing larvae of both sugarcane borers andcontrasted parasitoid wasp emerged from each one. The host finding test was conducted in an arena designed to not allow visual cues to the wasps. The parasitoid wasp in both tests showed no parasitism preference toward a sugarcane borer species being able to find and parasitize both borers similarly. The fertility life table parameters for C. flavipes parasitizing D. saccharalis andD. flavipennella were estimated based on the development and the specific daily parasitism obtained in the laboratory. The results show that C. flavipes exhibited similar parasitism and fertility on both borers, but with longer mean generation time and lower cocoon viability parasitizing D. flavipennella. Based on the results of the parasitism behavior and fertility life tablewe conclude that the parasitism of C. flavipes on D. flavipennella was not compromised. / As espécies Diatraea saccharalis (Fabr.) e Diatraea flavipennella (Box) (Lepidoptera: Crambidae) encontram-se distribuídas em todo o Brasil e no Nordeste, respectivamente. O controle dessas brocas, no Brasil, é a liberação do parasitóide Cotesia flavipes (Cam.) (Hymenoptera: Braconidae). No entanto, mais recentemente o controle de D. flavipennella com C. flavipes tem sido questionado em virtude da crescente ocorrência desta espécie nos canaviais do nordeste do Brasil. Assim, este trabalho investigou o desempenho de C. flavipes em D. saccharalis e D. flavipennella, com estudos de comportamento de escolha e parasitismo, bem como de biologia. Foram conduzidos estudos envolvendo testes de livre escolha para preferência e localização do hospedeiro em arenas. Lagartas das duas espécies de Diatraea foram ofertadas a fêmeas de C. flavipes com 24h de idade, acasaladas e alimentadas. Vespas criadas em lagartas de uma das brocas foram testadas individualmente, tendo como hospedeiro D. flavipennella e D.saccharalis, ou ambas as espécies. Os testes de localização do hospedeiro foram conduzindos usando arenas que permitiam as vespas utilizarem apenas pistas olfativas, pistas olfativas e visuais. Os resultados mostraram que as vespas não tiveram preferência de escolha, sendo C.flavipes capaz de localizar ambas as brocas. Em outro experimento, com dados de C. flavipes parasitando as duas brocas, foi confeccionada a tabela de vida de fertilidade do parasitóide nas duas espécies de Diatraea. A partir dos resultados encontrados observou-se que C. flavipes apresentou parasitismo similar nas duas brocas, mas com maior tempo de desenvolvimento e menor viabilidade de casulos em D. flavipennella. Com base nos resultados de comportamento, desenvolvimento e parasitismo de C. flavipes, pode-se concluir que o desempenho de C. flavipesnão foi comprometido em ambas às brocas.

A magnitude do problema de Diatraea saccharalis (Fabricius) tem aumentado nos últimos anos, principalmente nas culturas de cana-de-açúcar e milho no Brasil. Tradicionalmente, D. saccharalis tem sido controlado com agentes de controle biológico, principalmente na cultura da cana-de-açúcar. No entanto, a intervenção química tem sido necessária para o controle de D. saccharalis em ambas as culturas. Visando estabelecer estratégias proativas para o manejo da resistência de D. saccharalis a inseticidas e integrar as táticas de controle químico e biológico, objetivou-se nesse trabalho avaliar a toxicidade de alguns inseticidas (triflumuron, lambdacyhalothrin e fipronil) a D. saccharalis e ao parasitóide Cotesia flavipes (Cameron). A caracterização das linhas-básicas de suscetibilidade de D. saccharalis a esses inseticidas foi realizada com bioensaio de ingestão, mediante contaminação da superfície da dieta artificial com o inseticida, utilizando-se lagartas de 2º instar. Baseado nas curvas de concentração-mortalidade da população suscetível de referência, foram definidas as concentrações diagnósticas de 320 µg de triflumuron /mL de água [I.A.(ppm)], 32 µg de fipronil /mL de água, e 3,2 µg de lambdacyhalothrin/ mL de água, correspondentes à CL99, para o monitoramento da resistência Foram verificadas diferenças significativas na suscetibilidade a inseticidas em populações de D. saccharalis coletadas em diferentes regiões produtoras de milho no Brasil e uma no Paraguai. Para triflumuron, as sobrevivências variaram de 0,85 e 34,2%; para fipronil de 0,21 e 2,71%; e para lambda-cyhalothrin de 0,21 a 7,9%. A toxicidade desses inseticidas sobre C. flavipes foi avaliada mediante determinações de efeitos letal e subletal desses inseticidas sobre adultos do parasitóide. Inicialmente foram avaliadas as concentrações recomendadas de 0,08 mg de triflumuron/L de água e 0,075 mg de lambda-cyhalothrin/L de água, além de 10 e 50% da concentração recomendada, mediante bioensaio de contato residual em discos de folha de canade- açúcar de resíduos com 0, 24 e 48 h de idade. A maior toxicidade foi observada com lambdacyhalothrin (mortalidade de até 100%). Triflumuron causou mortalidade de mortalidade de no máximo 32%. Observou-se também uma redução da longevidade de C. flavipes em todas as concentrações e idade de resíduos para ambos inseticidas. Posteriormente, para avaliar os efeitos indiretos de inseticidas sobre C. flavipes, lagartas sobreviventes de D. saccharalis a CL25 de triflumuron, lambda-cyhalothrin e fipronil foram expostas a C. flavipes para parasitismo. A capacidade de parasitismo foi também avaliada para a geração F1 do parasitóide. Nenhum dos inseticidas afetou a emergência de adultos, a mortalidade de larvas e pupas, e a razão sexual do parasitóide. Por outro lado, lambda-cyhalothrin e fipronil afetaram negativamente a taxa instantânea de crescimento de C. flavipes. Portanto, as estratégias de uso destes inseticidas para o controle de D. saccharalis devem ser implementadas com cautela para preservar a vida útil desses importantes inseticidas em programas de manejo integrado de pragas. / The magnitude of Diatraea saccharalis (Fabricius) problem has increased in the past years, mainly in sugarcane and maize crops in Brazil. Traditionally, D. saccharalis has been controlled with biological control agents. However, chemical intervention has been necessary to control D. saccharalis in both crops. For establishing a proactive insecticide resistance management of D. saccharalis and integrating chemical and biological control tactics, the major objective of this work was to evaluate the toxicity of some insecticides (triflumuron, lambdacyhalothrin e fipronil) to D. saccharalis and to the parasitoid Cotesia flavipes (Cameron). The baseline susceptibility of D. saccharalis to these insecticides was characterized with diet surface treatment bioassay by using 2nd instar larvae. Based on concentration-mortality response of the susceptible reference population, diagnostic concentrations of 320 µg of triflumuron/mL of water [A.I. (ppm)], 32 µg of fipronil/mL of water, and 3.2 µg de lambda-cyhalothrin/mL of water, corresponding to LC99, were defined for monitoring resistance. Significant differences in susceptibilities to insecticides were found in populations of D. saccharalis collected from major maize-production regions and one population from Paraguay. For triflumuron, the survivorship varied from 0.8 to 34.2%; for fipronil, from 0.2 to 2.7%; and for lambda-cyhalothrin, from 0.2 to 7.9%. The toxicity of these insecticides to C. flavipes was evaluated by determining the lethal and sublethal effects of the insecticides to the adults of this parasitoid. Initially, commercial rates of 0.08 mg triflumuron/ L of water and 0.075 mg lambda-cyhalothrin / L of water, and 10% and 50% of commercial rates, were evaluated with residual contact bioassay by using sugarcane leaf disks of 0, 24 and 48 h-old residues. The highest toxicity was detected to lambda-cyhalothrin (mortality up to 100%). Triflumuron caused mortality up to 32%. Reduction in the longevity of C. flavipes was detected in all concentrations and residue ages of both insecticides. Then, to evaluate the indirect effect of the insecticides, D. saccharalis larvae that survived at LC25 of triflumuron, lambda-cyhalothrin and fipronil were exposed to C. flavipes. The parasitism capacity of F1 generation of the parasitoid was also evaluated. None of the insecticide affected the adult emergence, pupal and larval mortality, and sexual ratio of the parasitoid. On the other hand, lambda-cyhalothrin e fipronil negatively affect the instantaneous rate of growth of C. flavipes. Therefore, the strategies of the use of these insecticides for controlling D. saccharalis should be carefully designed to preserve their lifetime in integrated pest management programs.

Host recognition behaviour of two braconid larval parasitoids Cotesia sesamiae and Cotesia flavipes was studied using suitable stemborer hosts [i.e. Busseola fusca for C. sesamiae, and Chilo partellus for C. flavipes] and one non-host [Eldana saccharina]. The wasps displayed similar sequences of behavioural steps when locating their hosts largely depending on their antennae for host recognition and both antennae and tarsi for final host acceptance and oviposition. Tactile and contact chemoreception stimuli from the hosts seem to play a major role in oviposition decision by the parasitoids. In addition, the external morphology and distribution pattern of sensilla present on antennae, tarsi and ovipositor of the parasitoids were examined by scanning electron and optic microscopy after staining with silver nitrate. Three sensillar types were identified on the distal antennomeres: (i) non-porous sensilla trichoidea most probably involved in mechanoreception, (ii) uniporous sensilla chaetica likely to be gustatory and, (iii) multiporous sensilla placodea likely to be olfactory. The tarsi possess a few sensilla chaetica which could be gustatory while the manubrium is likely to be used in detection of vibrations. The distal end of the ovipositor bears numerous multiporous dome-shaped sensilla. Additionally, the ability of the wasps to discriminate between contact cues was studied. When host larvae were washed in distilled water the wasps did not insert their ovipositors. However, ovipositor insertion resumed when washed host or non-host larvae were painted with water extracts of their respective host larvae. The water extracts of the suitable hosts were more attractive to the wasps than those of non-hosts. Similarly, the frass is important in host recognition during short-range examination as those of respective hosts are more intensely antennated than of non-hosts. The parasitoids were able to discriminate the regurgitant of E. saccharina by not antennating the cotton wool ball of this host; while the regurgitant of B. fusca and C. partellus appeared not useful in discriminating between the two species for both parasitoid species. Further analysis suggests the presence of a protein(s) component(s) in the regurgitant possibly responsible for host recognition and oviposition by C. flavipes. / Thesis (Ph.D. (Environmental Science))--North-West University, Potchefstroom Campus, 2009.