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Made available in DSpace on 2020-12-11T15:32:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-06-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Telenomus remus Nixon (Hymenoptera Scelionidae) and Trichogramma pretiosum Riley (Hymenoptera Trichogrammatidae) are widely used for the control of lepidopteran pests in several countries, but applied programs using these parasitoids in peanuts are still rare. Therefore, the comparative parasitism capacity of T. remus and T. pretiosum in Stegasta bosqueella (Chambers) (Lepidoptera Gelechiidae), Spodoptera cosmioides (Walker) and Spodoptera frugiperda (J.E. Smith) (Lepidoptera Noctuidae) eggs were studied under controlled conditions (12L:12D photoperiod, 25 +/- 1 degrees C, and 70 +/- 10% RH). Eggs of S. bosqueella, S. cosmioides and S. frugiperda were offered daily throughout the adult lifespan of the parasitoids. Both parasitoids did not parasitize eggs of S. bosqueella. Eggs of Spodoptera spp. were significantly more parasitized by T. remus than by T. pretiosum. These two parasitoids presented the highest parasitism rate in the first 24 hours in Spodoptera eggs. However, to obtain 80% of parasitism in Spodoptera spp. took up to seven days for T. remus and up to three days for T. pretiosum. Telenomus remus demonstrated a longer lifespan, greater number of emerged parasitoids, and a female-biased sexual ratio, which might result in a greater potential control of Spodoptera spp. in the field. For S. bosqueella, other biological control agents should be considered. Sao Paulo State Univ, UNESP, Sch Agr & Vet Sci, Jaboticabal, SP, Brazil UNESP, Fac Ciencias Agr & Vet, Rod Prof Paulo Donato Castellane,Km 5, BR-14884900 Jaboticabal, SP, Brazil Sao Paulo State Univ, UNESP, Sch Agr & Vet Sci, Jaboticabal, SP, Brazil UNESP, Fac Ciencias Agr & Vet, Rod Prof Paulo Donato Castellane,Km 5, BR-14884900 Jaboticabal, SP, Brazil CAPES: 001

Made available in DSpace on 2020-12-12T02:42:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Telenomus remus Nixon (Hymenoptera Scelionidae) and Trichogramma pretiosum Riley (Hymenoptera Trichogrammatidae) are widely used for the control of lepidopteran pests in several countries, but applied programs using these parasitoids in peanuts are still rare. Therefore, the comparative parasitism capacity of T. remus and T. pretiosum in Stegasta bosqueella (Chambers) (Lepi-doptera Gelechiidae), Spodoptera cosmioides (Walker) and Spodoptera frugiperda (J.E. Smith) (Lepidoptera Noctuidae) eggs were studied under controlled conditions (12L:12D photoperiod, 25 ± 1 °C, and 70 ± 10% RH). Eggs of S. bosqueella, S. cosmi-oides and S. frugiperda were offered daily throughout the adult lifespan of the parasitoids. Both parasitoids did not parasitize eggs of S. bosqueella. Eggs of Spodoptera spp. were significantly more parasitized by T. remus than by T. pretiosum. These two parasi-toids presented the highest parasitism rate in the first 24 hours in Spodoptera eggs. However, to obtain 80% of parasitism in Spodoptera spp. took up to seven days for T. remus and up to three days for T. pretiosum. Telenomus remus demonstrated a long-er lifespan, greater number of emerged parasitoids, and a female-biased sexual ratio, which might result in a greater potential control of Spodoptera spp. in the field. For S. bosqueella, other biological control agents should be considered. School of Agricultural and Veterinarian Sciences São Paulo State University (UNESP) School of Agricultural and Veterinarian Sciences São Paulo State University (UNESP) CAPES: 001

The rosy apple aphid, Dysaphis plantaginea, and the codling moth, Cydia pomonella, are major insect pests in apple orchards causing high economic losses. A conservation biological control approach using plant species that provide resources for natural enemies may improve natural regulation and reduce insecticide use. In this study, we compared the influence of wildflower strips, grass strips and spontaneous vegetation on the biological control of aphids and moths by their natural enemies (parasitoids, hoverflies, and ladybirds) in three untreated apple orchards in 2014 and 2015. The sown wildflower strip mixture was successful in increasing floral resource provisioning in both years. Among the major natural enemy groups observed in the margin strips only hoverflies responded positively to the increase of floral resources. Within the orchards, the number of aphid colonies per tree was higher close to the margins, but the number of codling moth larvae smaller. The number of natural enemies observed in aphid colonies was largely driven by aphid number. None of the natural enemy groups observed in D. plantaginae colonies responded to the adjacent strip treatments. This dynamic response may explain the reduction in aphid numbers close to wildflower strips without finding higher overall natural enemy numbers. Similarly, codling moth parasitism was higher close to the margins. These results suggest a positive influence of floral resource provisioning by wildflower strips on aphid predation and codling moth parasitism but they also demonstrate that effect size may be small if species-rich spontaneous vegetation does already occur in margins or inside orchards

Onion (Allium cepa) is one of the most cultivated and consumed vegetables in Brazil and its importance is due to the large laborforce involved. One of the main pests that affect this crop is the Onion Thrips (Thrips tabaci), but the spatial distribution of this insect, although important, has not been considered in crop management recommendations, experimental planning or sampling procedures. Our purpose here is to consider statistical tools to detect and model spatial patterns of the occurrence of the onion thrips. In order to characterize the spatial distribution pattern of the Onion Thrips a survey was carried out to record the number of insects in each development phase on onion plant leaves, on different dates and sample locations, in four rural properties with neighboring farms under different infestation levels and planting methods. The Mantel randomization test proved to be a useful tool to test for spatial correlation which, when detected, was described by a mixed spatial Poisson model with a geostatistical random component and parameters allowing for a characterization of the spatial pattern, as well as the production of prediction maps of susceptibility to levels of infestation throughout the area. A cebola é uma das hortaliças mais cultivadas e consumidas no Brasil e sua importância social se deve à grande demanda por mão-de-obra. Uma das principais pragas que afeta essa cultura é o tripes do prateamento (Thrips tabaci) e sua distribuição espacial, embora importante, não tem sido considerada nas recomendações de manejo da cultura, planejamento de experimentos ou estudos amostrais. O objetivo desse artigo foi considerar métodos estatísticos para detectar e modelar padrões espaciais na ocorrência do tripes do prateamento da cebola. Para caracterizar o padrão espacial da dispersão do tripes do prateamento da cebola foi feito um levantamento anotando-se o número de insetos por fase de desenvolvimento em folhas de plantas de cebola, em diferentes datas e pontos amostrais dentro de quatro propriedades com fazendas vizinhas apresentando diferentes níveis de infestação e métodos de plantio. O teste de aleatorização de Mantel mostrou-se útil para testar a presença de padrão espacial, que quando detectado foi descrito por um modelo de Poisson misto espacial com componente aleatório geoestatístico com parâmetros que possibilititam a caracterização do padrão espacial, bem como a obtenção de mapas de predição dos níveis de susceptibilidade à infestação na área.

Sci. Agric. (Piracicaba, Braz.), v.66, n.1, p.90-99, January/February 2009. Submitted by Rodrigo Meirelles (rodrigomei@ufba.br) on 2011-08-09T15:24:11Z No. of bitstreams: 1 a13v66n1.pdf: 494501 bytes, checksum: 505eeaf0fd49ffb1a3acf99b3060ab62 (MD5) Made available in DSpace on 2011-08-09T15:24:11Z (GMT). No. of bitstreams: 1 a13v66n1.pdf: 494501 bytes, checksum: 505eeaf0fd49ffb1a3acf99b3060ab62 (MD5) Previous issue date: 2009 Onion (Allium cepa) is one of the most cultivated and consumed vegetables in Brazil and its importance is due to the large laborforce involved. One of the main pests that affect this crop is the Onion Thrips (Thrips tabaci), but the spatial distribution of this insect, although important, has not been considered in crop management recommendations, experimental planning or sampling procedures. Our purpose here is to consider statistical tools to detect and model spatial patterns of the occurrence of the onion thrips. In order to characterize the spatial distribution pattern of the Onion Thrips a survey was carried out to record the number of insects in each development phase on onion plant leaves, on different dates and sample locations, in four rural properties with neighboring farms under different infestation levels and planting methods. The Mantel randomization test proved to be a useful tool to test for spatial correlation which, when detected, was described by a mixed spatial Poisson model with a geostatistical random component and parameters allowing for a characterization of the spatial pattern, as well as the production of prediction maps of susceptibility to levels of infestation throughout the area. São Paulo

This research aimed at studing Telenomus remus Nixon biology reared on Spodoptera frugiperda (J.E. Smith) eggs at different temperatures. Based on the development of the cycle (egg-adult), the thermal requirements and the number of parasitoid generations at constant temperatures were determined. Initially, 24-hour-old S. frugiperda eggs were submitted to parasitism by T. remus during 5 h, being then transferred to acclimatized chambers regulated at 15, 20, 25, 28, 31, and 35°C. The cycle (egg to adult) was influenced by temperature varying from 8.3±0.01 to 47.2±0.01 for females and 8.1±0.01 to 46.8±0.01 days for males at 31 and 15°C, respectively. The emergency (%) was also influenced by temperature. A reduction in emergency was observed at 15°C and no emergency at 35°C. T. remus sex ratio was not influenced by temperature. Sexual rate was not changed by temperature. Regarding to thermal requirements, thermal constant (K) and inferior thermal threshold (Tb) were higher for T. remus females (158.88 degree-days and 12.5°C) when compared to males (154.12 degree-days and 12.6°C). The estimated number of T. remus generation per year for males and females at laboratory conditions was 5.6 and 5.6, 16.9 and 17.3, 28.3 and 29.0, 35.1 and 36.0, 39.6 and 40.7 at 15, 20, 25, 28, and 31oC, respectively. Este trabalho teve como objetivo estudar a biologia de Telenomus remus Nixon criado em ovos de Spodoptera frugiperda (J.E. Smith) em diferentes temperaturas. Com base no desenvolvimento do ciclo (ovo-adulto), foram determinados as exigências térmicas e o número de gerações dos parasitóides em temperaturas constantes. Inicialmente, ovos de S. frugiperda, com 24 horas de idade, foram submetidos ao parasitismo por T. remus, durante cinco horas, sendo então transferidos para câmaras climatizadas reguladas para as temperaturas de 15, 20, 25, 28, 31 e 35°C. A duração do ciclo (ovo-adulto) foi influenciada pela temperatura variando de 8,3±0,01 a 47,2±0,01 dias para fêmeas e 8,1±0,01 a 46,8±0,01 dias para machos de T. remus nas temperaturas de 31 e 15°C, respectivamente. A porcentagem de emergência (viabilidade) de T. remus em ovos de S. frugiperda também foi influenciada pela variação da temperatura, apresentando redução significativa apenas nas temperaturas extremas. Foi observada redução na viabilidade a 15°C e não houve desenvolvimento biológico do parasitóide a 35°C. A razão sexual de T. remus não sofreu influência da temperatura. Em relação às exigências térmicas, a constante térmica (K) e temperatura base (Tb) foram maiores para as fêmeas de T. remus (158,88 graus dias e 12,52°C) quando comparadas aos machos (154,12 graus dias e 12,59°C). A estimativa do número de gerações anuais para T. remus para machos e fêmeas em condições de laboratório foi respectivamente 5,6 e 5,6; 16,9 e 17,3; 28,3 e 29,0; 35,1 e 36,0; 39,6 e 40,7 nas temperaturas de 15, 20, 25, 28 e 31°C.