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The spotted spider mite, Tetranychus urticae (Koch, 1836), is one of the most important pests of strawberry production systems worldwide. Because plant resistance is an important integrated management strategy, the present study investigated the effects of 12 strawberry genotypes on the biological characteristics of this pest under laboratory conditions (25 ± 2 °C and RH 60 ± 10%; 12:12-hour photophase). The experiment was carried using 12 treatments (genotypes), divided into 20 replications each, in a completely randomized design. The response variables were the biological parameters of the spider mite and its survival rate. The development and survival of T. urticae were influenced by different strawberry genotypes. The Camarosa cultivar together with genotypes Selection 05 and 2017-04-03 negatively affected the development and survival of T. urticae. The Selection 02 genotype had greatest susceptibility to the spider mite, which allowed fast development and high survival rate. The reproductive parameters of T. urticae were affected differently as a function of the strawberry genotype, with the Camarosa cultivar and the genotypes Selection 05 and 2017-04-03 being unfavorable to development, suggesting a possible resistance based on antibiosis. [ABSTRACT FROM AUTHOR]

ABSTRACT: The aim of this study was to evaluate the bioactivity of microencapsulated extract from the soursop seeds, Annona muricata L. ( Annonaceae ), on diamondback moth, Plutella xylostela L. (Lepidoptera: Plutellidae ). Microencapsulation was performed in a Mini Spray Dryer model B-290 using 50mL of ethanolic and hexanic extracts plus 150mL of ethanol and 150mL of ultrapure water, mixed with aerosil (first polymer) or arabic gum (second polymer). It was possible to microencapsulate the ethanolic extract of soursop seeds only by using the polymer arabic gum at 20%. The microencapsulated extract caused significant acute toxicity (LC50=258mg L-1) and chronic effects, especially reduction of larval viability and increased larval stage. We concluded that the microencapsulation of the ethanolic extract of soursop seeds can be a viable alternative for controlling diamondback moth with possible gains for the environment.

ABSTRACT: Given the increasing importance of Elaphria agrotina (Guenée) (Lepidoptera: Noctuidae) in corn crops, especially in the Brazilian Savannah biome, the present research aimed to study its development and survival on Greene’s and Poitout & Bues’s artificial diets (25±1°C, 70±10% relative humidity [RH] and 12h photophase). Poitout & Bues’s diet was more suitable than Greene’s diet, providing higher survival percent (77.51% vs. 5.57%), lower development time (49.81 days vs. 55.24 days) and higher fecundity (167.65 vs. 84.9 eggs), respectively. All the caterpillars reared on Poitout & Bues’s diet passed through six instars, while almost half of the larvae reared on Greene’s diet went through one less instar stage. Regarding the main reproductive parameters, higher average time of generation (T) and lower values of net rates of reproduction (Ro), and increased (rm) intrinsic and finite reason of increase (λ), were observed for larvae reared on Greene’s diet. Results presented in this study indicated that Poitout & Bues’s diet is more suitable for maintenance of colonies of E. agrotina as compared to Greene’s diet.

Given the increasing importance of Elaphria agrotina (Guenée) (Lepidoptera: Noctuidae) in corn crops, especially in the Brazilian Savannah biome, the present research aimed to study its development and survival on Greene S and Poitout & Bues S artificial diets (25±1°C, 70±10% relative humidity [RH] and 12h photophase). Poitout & Bues's diet was more suitable than Greene's diet, providing higher survival percent (77.51% vs. 5.57%), lower development time (49.81 days vs. 55.24 days) and higher fecundity (167.65 vs. 84.9 eggs), respectively. All the caterpillars reared on Poitout & Bues 's diet passed through six instars, while almost half of the larvae reared on Greene 's diet went through one less instar stage. Regarding the main reproductive parameters, higher average time of generation (T) and lower values of net rates of reproduction (Ro), and increased (rm) intrinsic andfinite reason of increase (X), were observed for larvae reared on Greene 's diet. Results presented in this study indicated that Poitout & Bues 's diet is more suitable for maintenance of colonies of E. agrotina as compared to Greene 's diet. [ABSTRACT FROM AUTHOR]

The leafminer Liriomyza sativae Blanchard is an important insect pest on melon crops in Brazil. However, the information about its biology on melon (Cucumis melo L.) is scarce. Therefore, the aim of this research was to know some biological aspects of this pest, reared on melon plants, under laboratory conditions at 25°C. Our results showed that the biological cycle of L. sativae lasts 15.9±0.04 days (egg-adult), namely: egg (2.7±0.01 days), larva (4.1±0.03 days) and pupa (9.1±0.03 days). The sex ratio is 0.51 and the females live (19.3±1.09 days) longer than males (16.2±0.96 days). These results can help in the integrated management of L. sativae on melon crops and improve the systems for rearing this leafminer in laboratory.A mosca-minadora Liriomyza sativae Blanchard é uma praga importante em cultivos de meloeiro (Cucumis melo L.) no Brasil. No entanto, as suas informações sobre biologia, em meloeiro, são escassas. Portanto, o objetivo deste trabalho foi conhecer alguns aspectos biológicos dessa praga, criada em plantas de meloeiro, em condições de laboratório a 25°C. As informações obtidas mostram que o ciclo biológico de L. sativae é de 15,9±0,04 dias (ovo-adulto), sendo: ovo (2,7±0,01 dias), larva (4,1±0,03 dias) e pupa (9,1±0,03 dias). A razão sexual é de 0,51 e as fêmeas vivem mais tempo (19,3±1,09 dias) que os machos (16,2±0,96 dias). Essas informações podem auxiliar na adoção de medidas de manejo integrado de L. sativae em cultivos de meloeiro e melhorar os sistemas de criação da mosca minadora em laboratório.

The objective of this study was to evaluate extent of larval period, larval survival (%), food consumption, and pupal biomass of Spodoptera eridania and Spodoptera frugiperda (Lepidoptera: Noctuidae) fed on fresh ears of field corn expressing Bt proteins (Cry1F and Cry1F+Cry1A.105+Cry2Ab2). Larvae of Spodoptera spp. survived less than two days when they consumed Bt corncobs and showed 100% mortality. Spodoptera eridania reared on non-Bt corn cobs showed higher larval development (21.6 days) than S. frugiperda (18.4 days) and lower viability (56.4% and 80.2% for S. eridania and S. frugiperda, respectively). A higher amount of corn grains was consumed by S. eridania (5.4g) than by S. frugiperda (3.9g). In summary, this study demonstrated that the toxins Cry1F and Cry1F + Cry1A.105 + Cry2Ab2 expressed in fresh corn cobs contributed to protect ears of corn against S. frugiperda and the non-target pest S. eridania. However, itis important to monitor non-Bt cornfields because of the potential of both species to cause damage to ear sof corn. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the bioactivity of microencapsulated extract from the soursop seeds, Annona muricata L. (Annonaceae), on diamondback moth, Plutella xylostela L. (Lepidoptera: Plutellidae). Microencapsulation was performed in a Mini Spray Dryer model B-290 using 50mL of ethanolic and hexanic extracts plus 150mL of ethanol and 150mL of ultrapure water, mixed with aerosil (first polymer) or arabic gum (second polymer). It was possible to microencapsulate the ethanolic extract of soursop seeds only by using the polymer arabic gum at 20%. The microencapsulated extract caused significant acute toxicity (LC50=258mg L-1) and chronic effects, especially reduction of larval viability and increased larval stage. We concluded that the microencapsulation of the ethanolic extract of soursop seeds can be a viable alternative for controlling diamondback moth with possible gains for the environment. [ABSTRACT FROM AUTHOR]

O presente trabalho teve por objetivo estudar os aspectos biológicos, morfológicos e comportamentais de uma linhagem unipariental de Aspidiotus nerii Bouché, 1833 (Hemiptera: Diaspididae), sob condições controladas (25±1oC, 70±10% de UR e 12 horas de fotofase), tendo abóboras híbridas "cabotiá" como hospedeiro. Ninfas recém-eclodidas foram transferidas da criação massal para abóboras "cabotiá", devidamente higienizadas, dispostas em câmaras climatizadas. O período médio para fixação das ninfas móveis foi de 2,4±0,33 horas. A duração média do 1° e 2° estádios, após a fixação das ninfas, foi de 8,3±0,06 e 19,4±0,11 dias, respectivamente, totalizando fase ninfal média de 27,9±0,11 dias. Das ninfas que atingiram a fase adulta, 36 fêmeas foram acompanhadas diariamente até o final do ciclo. A duração média dos períodos pré-reprodutivo e reprodutivo foi de 17,3±0,18 e 68,2±4,33 dias, respectivamente. O número total médio de ninfas/fêmea foi 175,5±10,29 e o número médio de ninfas/fêmea/dia foi 2,7±0,11. A longevidade média das fêmeas foi 100,5±4,51 dias.The objective of this work was to study the biology, morphology and behavior of Aspidiotus nerii Bouché, 1833 (Hemiptera: Diaspididae) under controlled conditions (25±1°C, 70±10% R.H. and 12 hours of photophase), using "cabotiá" cucumber pumpkins as hosts. Nymphs of the 1st stage obtained of mass rearing (mother culture) were transfered to "cabotiá" pumpkins, properly cleaned and disposed in acclimatized cameras. The medium period for fixation of the nymphs was of 2.4±0.33 hours. The 1st and 2nd stages, after the fixation of the nymphs, lasted 8.3±0.06 and 19.4±0.11 days, respectively, totalizing a nymphal phase of 27.9±0.11 days. 36 females were observed daily until the end of the cycle. The pre-reproductive and reproductive periods lasted 17.3±0.18 and 68.2±4.33 days, respectively. The medium total number of nymphs/female was 175.5±10.29 and the medium number of nymphs/female/day was 2.7±0.11. The female's longevity was 100.5±4.51 days.

O afídeo Myzus persicae (Sulzer, 1776) (Hemiptera: Aphididae) é uma das principais pragas de diversas culturas em condições de campo ou em cultivo protegido. Este trabalho teve por objetivo avaliar o efeito de diferentes temperaturas na longevidade e nos aspectos reprodutivos de M. persicae sobre berinjela (Solanum melongena L.). O experimento foi conduzido sob condições controladas de temperatura (15, 20, 25 e 30°C), umidade relativa do ar (70 ± 10%) e fotofase (12 horas). As unidades experimentais consistiram de placas de Petri contendo ágar-água solidificado (1%). Nestas placas, os afídeos foram mantidos individualmente sobre os discos foliares de berinjela (3 cm de diâmetro) em uma das temperaturas (tratamentos), com 25 repetições. Foram determinadas as curvas mais ajustadas aos parâmetros biológicos de M. persicae, suas equações de regressão e os respectivos coeficientes de determinação (R²). A temperatura influenciou todos os parâmetros avaliados. As durações dos períodos pré-reprodutivo e reprodutivo de M. persicae variaram de 0,46 dia (25°C) a 1,12 dia (15°C) e de 3,89 dias (25°C) a 19,11 dias (15°C), respectivamente. A fecundidade total e diária foi de 17,63 ninfas/fêmea e 4,38 ninfas/fêmea/dia a 25°C; 43,63 ninfas/fêmea e 4,34 ninfas/fêmea/dia a 20°C; 60,65 ninfas/fêmea e 3,15 ninfas/fêmea/dia a 15°C. A 30°C, não houve reprodução. A duração do período pós-reprodutivo variou de 0,89 dia (25°C) a 3,72 dias (15°C). A longevidade do afídeo diminuiu com o aumento da temperatura, de 23,95 dias (15°C) para 5,06 dias (25°C). Temperaturas entre 15 e 20°C são mais favoráveis a M. persicae.

Algumas características biológicas de Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) criadas em tubérculos de batata, foram estudadas em laboratório a 25 ± 1ºC, 70 ± 10% de umidade relativa e fotofase de 14 horas. A longevidade dos machos foi de 33,4 dias e das fêmeas foi de 31,7 dias, a sobrevivência foi de 100% até o sexto dia para ambos os sexos, e o número médio total de ovos por fêmea de P. operculella foi 195, com viabilidade de 46,3%, quando esses foram alimentados com solução de mel a 10%.

O presente trabalho objetivou o estudo de parte do ciclo da Babesia bovis no seu hospedeiro invertebrado, o carrapato Boophilus microplus. Analisou-se a capacidade de infeccção e transmissão transovariana de B. bovis em partenóginas de B. microplus, alimentadas em bovinos portadores e enfermos por esse protozoário. No 18º dia após a infestação, coletaram-se partenóginas diretamente do corpo dos bovinos e teleóginas após o desprendimento natural, a partir do 21º dia. Todos os grupos foram incubados a 27ºC e umidade relativa superior a 70%. No 5º dia após o início da postura, realizou-se o exame de hemolinfa a fim de diagnosticar a infecção dos ínstares por B. bovis. A ausência de infecção detectada no exame de hemolinfa foi confirmada posteriormente com o teste biológico, revelando que partenóginas não transmitem B. bovis transovarianamente. Esses resultados oferecem uma técnica simplificada para a obtenção de cepas de carrapatos livres de B. bovis.In this experiment part of the life cycle of Babesia bovis in its invertebrate host, the tick Boophilus microplus was studied. In order to evaluate the capacity of infection and transmission of B. bovis were collected semi-engorged females of B. microplus fed on carrier and ill bovines. In the 18th day after infestation, semi-engorged females were collected directly from bovine bodies and after 21st day engorged females dropped on the ground. All the collected groups were incubated at 27°C and relative humidity greater than 70%. At the 5th day of oviposition the diagnosis was made by direct examination of haemolymph smears. The biological test reveled that B. bovis transovarial transmission doesn't happer in semi-engorged females. The results offer a simple techique to obtain strains of ticks free of B. bovis.

RESUMO Com a finalidade de obter informações básicas sobre biologia floral das espécies: C. brasilianum (L.) Benth., C. Virginianum (L) Benth., C. shottii (Mill.) K. Sch. e C. pascuorum (Mart.) Benth., foram estudados comparativamente três parâmetros biológicos: número de óvulos por ovário, sementes por vagem que chegaram à maturidade e grãos de pólen viáveis. Os dados foram coletados no Campo Experimental do Instituto de Genética da ESALQ/USP - Piracicaba, SP e no Jardim Botânico do Departamento de Biologia da Universidade Federal de Santa Maria (UFSM) - Santa Maria, RS. As diferenças ocorridas nos parâmetros analisados mostram, de uma certa forma, a individualidade comportamental de cada espécie, decorrente de uma sensibilidade e variabilidade específicas. Todas as espécies estudadas tiveram uma produção de óvulos férteis acima de 78% e pólen viável acima de 95%. que refletiu uma elevada porcentagem de sementes viáveis (com exceção de C. shottii e C. pascuorum - Santa Maria, RS), garantindo desta forma a perpetuação da espécie.

The leafminer Liriomyza sativae Blanchard is an important insect pest on melon crops in Brazil. However, the information about its biology on melon (Cucumis melo L.) is scarce. Therefore, the aim of this research was to know some biological aspects of this pest, reared on melon plants, under laboratory conditions at 25°C. Our results showed that the biological cycle of L. sativae lasts 15.9±0.04 days (eggadult), namely: egg (2.7±0.01 days), larva (4.1±0.03 days) and pupa (9.1±0.03 days). The sex ratio is 0.51 and the females live (19.3±1.09 days) longer than males (16.2±0.96 days). These results can help in the integrated management of L. sativae on melon crops and improve the systems for rearing this leafminer in laboratory. [ABSTRACT FROM AUTHOR]

As sementes do butiazeiro, Butia capitata (Martius) Beccari, são atacadas por um caruncho, Butiobruchus sp. Menos de 80% das larvas originam adultos. A maioria das larvas destrói apenas uma amêndoa. O bruquídeo não é fator limitante para a sobrevivência desta palmeira.Nuts of butia palm are attacked by a weevil, Butiobruchus sp. About 80% of the larvae gave origin to adults. Most of the larvae damages only one seed. This bruchid is not a limiting factor of the survival of this palm tree.