Beauveria bassiana (Ascomycota: Hypocreales)-treated Diamondback Moth (Lepidoptera: Plutellidae) Larvae Mediate the Preference and Functional Response of Euborellia annulipes (Dermaptera: Anisolabididae) Nymphs.

Biological control is one of the strategies to reduce populations of diamondback moth, Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae), the major pest of brassica. Entomopathogen-based biopesticides are recommended and used for its control, reducing the constant use of chemical pesticides. Predators and/or fungal entomopathogens have an increasing interest to be used against diamondback moth, and the compatibility of these control agents in the field is important for pest management. Here we experimentally investigate the effects of diamondback moth larvae treated with a biopesticidal formulation of Beauveria bassiana (Balsamo) Vuillemin in the feeding preference and functional response of the ring-legged earwig. We used untreated and B. bassiana-treated diamondback moth fourth instars (over a 24-h period of exposure) and Euborellia annulipes (Lucas) fifth instars. The nymphs were included in choice condition tests and different larval densities to the analysis of feeding preference and functional responses, respectively. Euborellia annulipes nymphs exhibited no feeding preference under choice conditions but presented different types of functional response: Type II on untreated and type III on fungus-treated diamondback moth larvae. The interaction between E. annulipes and B. bassiana observed in our study contributes to the understanding of the predator-prey-pathogen relationships with implications for P. xylostella integrated management strategies.

Carvacrol and linalool co-loaded in ß-cyclodextrin-grafted chitosan nanoparticles as sustainable biopesticide aiming pest control.

Pesticides are the main tactics for pest control because they reduce the pest population very fast and their efficiency does not depend on abiotic factors. However, the indiscriminate use of these substances can speed up the development of resistant populations and causing environmental contamination. Therefore, alternative methods of pest control are sought, such as the use of botanical compounds. Nanoencapsulation of volatile compounds has been shown to be an important tool that can be used to overcome the lack of stability of these compounds. In this work, we describe the preparation and characterization of chitosan nanoparticles functionalized with ß-cyclodextrin containing carvacrol and linalool. The toxicity and biological activity were evaluated. Decreases of toxicity were observed when the compounds were nanoencapsulated. The nanoparticles presented insecticidal activity against the species Helicoverpa armigera (corn earworm) and Tetranychus urticae (spider mite). In addition, repellent activity and reduction in oviposition were observed for the mites.

Molecular characterization of the gene profile of Bacillus thuringiensis Berliner isolated from Brazilian ecosystems and showing pathogenic activity against mosquito larvae of medical importance.

The occurrence of Aedes aegypti, Culex quinquefasciatus, and mosquitoes of the genus Anopheles potentiate the spread of several diseases, such as dengue, Zika, chikungunya, urban yellow fever, filariasis, and malaria, a situation currently existing in Brazil and in Latin America. Control of the disease vectors is the most effective tool for containing the transmission of the pathogens causing these diseases, and the bacterium Bacillus thuringiensis var. israelensis has been widely used and has shown efficacy over many years. However, new B. thuringiensis (Bt) strains with different gene combinations should be sought for use as an alternative to Bti and to prevent the resistant insects selected. Aiming to identify diversity in the Bt in different Brazilian ecosystems and to assess the pathogenicity of this bacterium to larvae of Ae. aegypti, C. quinquefasciatus, and Anopheles darlingi, Bt strains were obtained from the Amazon, Caatinga (semi-arid region), and Cerrado (Brazilian savanna) biomes and tested in pathogenicity bioassays in third-instar larvae of Ae. aegypti under controlled conditions in the laboratory. The isolates with larvicidal activity to larvae of Ae. aegypti were used in bioassays with the larvae of C. quinquefasciatus and An. darlingi and characterized according to the presence of 14 cry genes (cry1, cry2, cry4, cry10, cry11, cry24, cry32, cry44Aa, cry1Ab, cry4Aa, cry4Ba, cry10Aa, cry11Aa, and cry11Ba), six cyt genes (cyt1, cyt2, cyt1Aa, cyt1Ab, cyt2Aa and cyt2Ba), and the chi gene. Four hundred strains of Bt were isolated: 244 from insects, 85 from Amazon soil, and 71 from the Caatinga biome. These strains, in addition to the 153 strains isolated from Cerrado soil and obtained from the Entomopathogenic Bacillus Bank of Maranhão, were tested in bioassays with Ae. aegypti larvae. A total of 37 (6.7%) strains showed larvicidal activity, with positive amplification of the cry, cyt, and chi genes. The most frequently amplified genes were cry4Aa and cry4Ba, both occurring in 59.4% in these strains, followed by cyt1Aa and cyt2Aa, with 56.7% and 48% occurrence, respectively. Twelve (2.2%) strains that presented 100% mortality within 24h were used in bioassays to estimate the median lethal concentration (LC50) for Ae. aegypti larvae. Two strains (BtMA-690 and BtMA-1114) showed toxicity equal to that of the Bti standard strain, and the same LC50 value (0.003mg/L) was recorded for the three bacteria after 48h of exposure. Detection of the presence of the Bt strains that showed pathogenicity for mosquito larvae in the three biomes studied was possible. Therefore, these strains are promising for the control of insect vectors, particularly the BtMA-1114 strain, which presents a gene profile different from that of Bti but with the same toxic effect.

Effect of the insect growth regulator diflubenzuron on the predator Podisus nigrispinus (Heteroptera: Pentatomidae).

Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) is a common natural predator of defoliating caterpillars in agricultural and forest systems. Insecticides acting as growth regulators of insect pests can indirectly affect their predators through consumption of contaminated prey. We examined the reproductive performance of P. nigrispinus fed on caterpillars of Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae) reared on soybean leaves exposed to the chitin synthesis inhibitor, diflubenzuron. Caterpillars of A. gemmatalis were fed for 12 h with treated soybean leaves and offered to adults of the predator P. nigrispinus over five consecutive days. The fertility of P. nigrispinus was reduced when feeding on diflubenzuron treated caterpillars, especially at the beginning of the reproductive period, but recovered 3 weeks later. The effects of diflubenzuron ingestion on the life table parameters of P. nigrispinus included an increase in the period taken to double the population size, and reductions in the intrinsic rate of population increase, generation duration, and net reproductive rate. Diflubenzuron therefore had an indirect negative effect on the reproduction and the population dynamics of the non-target predator P. nigrispinus. Clearly, its use in integrated pest management requires further evaluation.

[Influence of nutritional substrates on the development of Diaphania hyalinata L. (Lepidoptera: Crambidae)]. / Influência do substrato alimentar sobre o desenvolvimento de Diaphania hyalinata L. (Lepidoptera: Crambidae).

The aim of this research was to evaluate the biological behaviour of melonworm at different natural and artificial diets. Squash cultivar jacaré, cucumber, summer squash and an artificial diets developed by Hensley & Hammond for the sugarcane borer were tried. The research was carried out in the Laboratório de Entomologia do Centro de Ciências Agrárias of the Universidade Federal do Espírito Santo, in climatized room at 25 +/- 1 masculineC, relative humidity of 70 +/- 10% and 14h photofase. The caterpillars fed on each substrate during the whole life cycle. Differences in duration of the larval period, larvae and pupae survival, adult longevity and number of eggs were registered between the substrates. The results show that the best diet for rearing is the artificial one. Between the natural diets the cucumber showed the best results.

Influência do substrato alimentar sobre o desenvolvimento de Diaphania hyalinata L. (Lepidoptera: Crambidae) / Influence of nutritional substrates on the development of Diaphania hyalinata L. (Lepidoptera: Crambidae)

Aspectos biológicos de Diaphania hyalinata L. foram estudados quando as lagartas foram criadas em dietas natural e artificial em condições de laboratório, a 25 ± 1ºC, umidade relativa de 70 ± 10 por cento e fotofase de 14h. Como dieta natural foi utilizada abóbora jacaré, pepino e abobrinha caserda e uma dieta artificial utilizada em criações de Diatraea saccharalis (Fabr.), desenvolvida por Hensley & Hammond. As lagartas de D. hyalinata foram colocadas nos diferentes substratos e criadas por todo o ciclo. Observaram-se diferenças na duração do período larval, sobrevivência das larvas e pupas, longevidade do adulto e número de ovos entre os substratos. A dieta artificial a que mostrou de modo geral, mais adequada para a criação de D. hyalinata. Entre as dietas naturais, o pepino foi o que se apresentou mais adequado para criação desta praga.

The aim of this research was to evaluate the biological behaviour of melonworm at different natural and artificial diets. Squash cultivar jacaré, cucumber, summer squash and an artificial diets developed by Hensley & Hammond for the sugarcane borer were tried. The research was carried out in the Laboratório de Entomologia do Centro de Ciências Agrárias of the Universidade Federal do Espírito Santo, in climatized room at 25 ± 1ºC, relative humidity of 70 ± 10 percent and 14h photofase. The caterpillars fed on each substrate during the whole life cycle. Differences in duration of the larval period, larvae and pupae survival, adult longevity and number of eggs were registered between the substrates. The results show that the best diet for rearing is the artificial one. Between the natural diets the cucumber showed the best results.

[Biology and thermal requirements of Trichogramma atopovirilia Oatman & Platner (Hymenoptera: Trichogrammatidae) parasitizing eggs of Diaphania hyalinata L. (Lepidoptera: Pyralidae)]. / Biologia e exigências térmicas de Trichogramma atopovirilia Oatman & Platner (Hymenoptera: Trichogrammatidae) em ovos de Diaphania hyalinata L. (Lepidoptera: Pyralidae).

The development and parasitism of Diaphania hyalinata L. eggs by Trichogramma atopovirilia Oatman & Platner and its thermal requirements were studied at the temperatures of 18, 21, 24, 27, 30 and 33 degrees C. Thirty eggs of D. hyalinata were exposed to three females of T. atopovirilia for 5h at 25 degrees C and incubated at the different temperatures. The developmental time from egg exposure to adult, parasitism viability, number of adults per parasitized host egg and progeny sex ratio were monitored. The developmental time from egg to adult emergence of the parasitoid exhibited inverse relationship to the temperature, lasting 24.12 days at 18 degrees C and 7.36 days at 33 degrees C. Parasitism viability at 24, 27 and 30 degrees C was higher than 90%. The ratio of T. atapovirilia adult produced per egg and its sex ratio were not affected when using D. hialynata as host. The lowest threshold temperature (Tb) and estimated degree-days over Tb required by T. atopovirilia to develop on eggs of D. hyalinata was 11.99 degrees C and 130.42 masculine C, respectively. Considering the temperature regimes of two areas where cucurbitaces are cultivated in Bahia State (Rio Real and Inhambupe County) it was estimated that T. atopovirilia can achieve more than 32 generation per year. The results suggest that T. atopovirilia has potential to control D. hyalinata eggs with better chance of success under temperature regimes ranging from 24 to 27 degrees C that meets the suitable field conditions for cropping cucurbitaces.

[First report of parasitism of the Trichogramma bruni Nagaraja (Hymenoptera: Trichogrammatidae) in eggs of urbanus proteus (L.) (Lepidoptera: Hesperiidae) in snap beans (Phaseolus vulgaris) ( L.)]. / Primeiro relato de Trichogramma bruni Nagaraja (Hymenoptera: Trichogrammatidae) parasitando ovos de Urbanus proteus (L.) (Lepidoptera: Hesperiidae) em feijão-vagem.

Aiming to verify the presence of eggs parasitoids of the genus Trichogramma, for using in the biological control of insects pests, were collected eggs from long tailed skipper butterfly, a lepidopteran defoliator of snap beans, which presented eggs with parasitism characteristics (dark eggs). The eggs were taken to the laboratory were 44.9% of parasitism was verified. Viability was 96.3%, with an average of 6.6 individuals per egg and a sexual ratio of 0.93. Male specimens were identified as Trichogramma bruni Nagaraja. It is the first report of parasitism in this host and culture.

Biologia e exigências térmicas de Trichogramma atopovirilia Oatman & Platner (Hymenoptera: Trichogrammatidae) em ovos de Diaphania hyalinata L. (Lepidoptera: Pyralidae) / Biology and thermal requirements of Trichogramma atopovirilia Oatman & Platner (Hymenoptera: Trichogrammatidae) parasitizing eggs of Diaphania hyalinata L. (Lepidoptera: Pyralidae)

A biologia de Trichogramma atopovirilia Oatman & Platner parasitando ovos de Diaphania hyalinata L. foi estudada nas temperaturas de 18, 21, 24, 27, 30 e 33°C e suas exigências térmicas foram determinadas. Trinta ovos do hospedeiro foram submetidos ao parasitismo na proporção de uma fêmea do parasitóide para 10 ovos, durante 5h, a 25°C e incubados nas diferentes temperaturas. Os parâmetros avaliados foram duração do ciclo ovo-adulto, viabilidade, número de indivíduos emergidos por ovo e razão sexual. A duração do período de desenvolvimento ovo-adulto apresentou relação inversa à temperatura e foi de 24,12 dias a 18°C e 7,36 dias a 33°C. A viabilidade do parasitismo a 24, 27 e 30°C foi superior a 90 por cento. O número de indivíduos emergidos por ovo hospedeiro e a razão sexual não sofreram influência da temperatura. A temperatura base (Tb) e a constante térmica (K) requerida por T. atopovirilia criados em ovos de D. hyalinata foi de 11,99°C e 130,42°C, respectivamente. Baseado nas médias térmicas de duas localidades de cultivo de cucurbitáceas da Bahia (Rio Real e Inhambupe) estimou-se que T. atopovirilia pode completar mais do que 32 gerações ao longo do ano. Estes resultados indicam que T. atopovirilia possui potencial de utilização para o controle de D. hyalinata com maiores chances de sucesso entre as temperaturas de 24°C e 27°C as quais também são apropriadas para o cultivo de cucurbitáceas.

The development and parasitism of Diaphania hyalinata L. eggs by Trichogramma atopovirilia Oatman & Platner and its thermal requirements were studied at the temperatures of 18, 21, 24, 27, 30 and 33°C. Thirty eggs of D. hyalinata were exposed to three females of T. atopovirilia for 5h at 25°C and incubated at the different temperatures. The developmental time from egg exposure to adult, parasitism viability, number of adults per parasitized host egg and progeny sex ratio were monitored. The developmental time from egg to adult emergence of the parasitoid exhibited inverse relationship to the temperature, lasting 24.12 days at 18°C and 7.36 days at 33°C. Parasitism viability at 24, 27 and 30°C was higher than 90 percent. The ratio of T. atapovirilia adult produced per egg and its sex ratio were not affected when using D. hialynata as host. The lowest threshold temperature (Tb) and estimated degree-days over Tb required by T. atopovirilia to develop on eggs of D. hyalinata was 11.99°C and 130.42°C, respectively. Considering the temperature regimes of two areas where cucurbitaces are cultivated in Bahia State (Rio Real and Inhambupe County) it was estimated that T. atopovirilia can achieve more than 32 generation per year. The results suggest that T. atopovirilia has potential to control D. hyalinata eggs with better chance of success under temperature regimes ranging from 24 to 27°C that meets the suitable field conditions for cropping cucurbitaces.

Primeiro relato de Trichogramma bruni Nagaraja (Hymenoptera: Trichogrammatidae) parasitando ovos de Urbanus proteus (L.) (Lepidoptera: Hesperiidae) em feijão-vagem / First report of parasitism of the Trichogramma bruni Nagaraja (Hymenoptera: Trichogrammatidae) in eggs of urbanus proteus (L) (Lepidoptera: Hesperiidae) in snap beans (Phaseolus vulgaris) (L.)

Visando averiguar a presença de parasitóides do gênero Trichogramma, para utilização no controle biológico de pragas na cultura do feijão-vagem, foram coletadas posturas de Urbanus proteus (L.) que apresentavam ovos com características de parasitismo (ovos escuros). Os ovos foram encaminhados ao laboratório, onde se observou 44,9 por cento de parasitismo. Constatou-se a viabilidade de 96.3 por cento, com a média de 6,6 indivíduos por ovo e razão sexual de 0,93. Espécimes machos foram identificados, mostrando tratar-se de Trichogramma bruni Nagaraja, espécie que até então não havia sido descrita nesse hospedeiro e cultura.

Aiming to verify the presence of eggs parasitoids of the genus Trichogramma, for using in the biological control of insects pests, were collected eggs from long tailed skipper butterfly, a lepidopteran defoliator of snap beans, which presented eggs with parasitism characteristics (dark eggs). The eggs were taken to the laboratory were 44.9 percent of parasitism was verified. Viability was 96.3 percent, with an average of 6.6 individuals per egg and a sexual ratio of 0.93. Male specimens were identified as Trichogramma bruni Nagaraja. It is the first report of parasitism in this host and culture.