Mortalidade e efeitos subletais de Bacillus thuringiensis Berliner em Spodoptera albula (Walker, 1857)

Pós-graduação em Agronomia (Entomologia Agrícola) - FCAV

Disappearance of fat body proteins during soldier differentiation in the neotropical termite Heterotermes tenuis (Isoptera: Rhinotermitidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Não preferência para alimentação e antibiose em cultivares de amendoim a Stegasta bosquella (Chambers) (Lepidoptera: Gelechiidae)

This work aimed to evaluate the attractiveness, non-preference for feeding and antibiosis in straight and runner growth habit peanut cultivars to Stegasta bosquella (Chambers). Eight cultivars were evaluated, four of straight growth habit (IAC Tatu, IAC 22, IAC 8112 and IAC 5) and four of runner growth habit (IAC Runner 886, IAC 147, IAC 125 and IAC 503). Free-choice and no-choice feeding tests were performed, using pairs of overlapped leaf discs with 1.0 cm diameter, which were placed in Petri dishes where third instar larvae of S. bosquella were released. The attractiveness to the larvae was assessed in predetermined times, in addition to the dry mass consumed. In the antibiosis assay, the biological parameters were evaluated: period and viability of larvae, pre-pupae, pupae, and total, weight of larvae and pupae, sex ratio and longevity. None of the runner growth habit cultivars exhibited non-preference for feeding-type resistance. Among the straight growth habit cultivars, IAC 5 and IAC 22 were the least attractive and consumed in the free-choice feeding test, and IAC 5 and IAC 8112 were the least attractive in the no-choice test. The runner growth habit cultivars IAC 147 and IAC Runner 886 affected the larval survival of S. bosquella, exhibiting antibiosis-type resistance. For the straight growth habit cultivars, IAC 22 and IAC 8112 affected the larval viability, presenting antibiosis-type resistance. The straight and runner growth habit cultivars did not influence the biological parameters of weight of pupae, sex ratio and longevity of S. bosquella.

Determinação dos tipos de resistência a Spodoptera cosmioides (Walker) (Lepidoptera: Noctuidae) em genótipos de soja

The aim of this work was to evaluate the resistance types in soybean genotypes to Spodoptera cosmioides (Walker) in laboratory. Soybean genotypes assessed were as follows: 'IAC 100'(resistance standard), 'BR16'(susceptible standard), 'Dowling', PI 227687, PI 274454, 'IGRA RA 626 RR', PI 227682, 'BRSGO 8360', 'IGRA RA 516 RR'and 'P 98Y11 RR'. Free-choice and no-choice feeding non-preference tests were done using two newly-hatched larvae per genotype or one third-instar larva per genotype in both tests. Larvae attractiveness was evaluated in different times, and at the end of the experiments the leaf area consumed was quantified. In the antibiosis test, newly-hatched larvae were individualized into Petri dishes, where leaflets of the genotypes were offered over the larval stage, and the following biological parameters were assessed: period and viability of larvae, pupae and overall (larvae + pupae), weight of larvae and pupae, sex ratio and adults longevity. Overall, in the feeding preference tests, significant differences were not found in leaf consumption among the genotypes. In the antibiosis assay, genotypes PI 227687, PI 227682 and 'IAC 100'caused 100% larval mortality and the lowest weight of larvae, ranging between 37.65 and 85.56 mg. All soybean genotypes evaluated do not exhibit feeding non-preference type resistance to S. cosmioides, and PI 227687, PI 227682 and 'IAC 100'highlighted for possessing antibiosis.

Resistance of collard greens to Ascia monuste orseis (Lepidoptera: Pieridae)

Ascia monuste orseis (Godart) (Lepidoptera: Pieridae) is a production limiting pest in collard greens, Brassica oleracea (L.) var. acephala, cultivation. Because of the overuse and harmful effects of synthetic insecticides on nontarget species, the use of insect-resistant cultivars can be a valuable strategy in pest control. In this study, newly hatched A. monuste orseis larvae were confined to the leaves of 29 collard greens cultivars under a controlled environment to investigate plant resistance. We evaluated the incubation period, duration of instars, total duration of the immature and pupal phases, the egg to adult life cycle duration, mortality per instar, total weight of fifth instar larvae and pupae (age = 24 h) and larval and pupal survival and eclosion. Antibiosis and/or antixenosis were observed in selected cultivars. The results show that Gigante I-915 (E) exhibited high larval mortality and that the Pires 1 de Campinas cultivar (P) prevented all pupae from proceeding to the adult stage. The Introdu double dagger es do municipio de Arthur Nogueira Z (Y), Cabocla (AA), Japonesa (R) and Manteiga de Mococa (M) cultivars prolonged the larval stage. Japonesa (R) and Introdu double dagger es do municipio de Arthur Nogueira Z (Y) increased the egg to adult developmental period, and the Japonesa (R) cultivar also prolonged the pupal stage. The Verde-escura (O), Crespa de Capo Bonito (I), Couve de folhas Manteiga 900 Legitima P, Alto (AB), Gigante I-915 (E) and Manteiga Ribeiro Pires I-2446 (H) cultivars reduced the larval weight of A. monuste orseis.

Estimating the development of the fennel aphid, Hyadaphis foeniculi (Passerini) (Hemiptera: Aphiididae), using non-linear models

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Resposta funcional da joaninha Cryptolaemus predando Cochonilha branca em diferentes temperaturas e substratos vegetais

This work was carried out to evaluate the functional response of Cryptolaemus montrouzieri Mulsant, 1850 (Coleoptera: Coccinellidae) fed with Planococcus citri Risso, 1813 (Hemiptera: Pseudococcidae) reared on a pumpkin hybrid (Cucurbita maxima x Cucurbita moscata) (Cucurbitaceae), seedlings of Rangpur lime (Citrus limonia) Rutaceae) and potato (Solanum tuberosum) (Solanaceae) at two temperatures. The predation rate of C. montrouzieri was measured using Petri dishes of 15 cm diameter with 1, 2, 4, 8, 16 and 24 adults of P. Citri. One third instar larva, one fourfh instar and one newly emerged adult (without differentiation of sex) of C. montrouzieri were added to each plate. The study was conducted in climatic chambers at temperatures of 25 and 30 degrees C and photophase of 12 hours. The predation rate was evaluated after 24 hours of prey exposition to the predator, by counting the number of preys trapped in the different treatments and control. The statistical design was completely randomized with four treatments x 6 subplots with 7 repetitions, the two temperatures. The values obtained were subjected to analysis of variance, to relate the number of scales preyed by larvae and adults of C. montrouzieri set up in different substrates. The amount of prey consumed by larvae and adults of the predator increased with increasing the prey density until it reaches a plateau, characterizing functional response type II. In general, the number of scales preyed by larvae and adults of C. montrouzieri was higher on potato and under temperature of 30 degrees C.

On-plant larval movement and feeding behavior of fall armyworm (Lepidoptera: Noctuidae) on reproductive corn stages

Spodoptera frugiperda J.E. Smith (fall armyworm) is considered one of the most destructive pests of corn throughout the Americas. Although this pest has been extensively studied, little is known about its larval movement and feeding behavior on reproductive compared to vegetative corn stages. Thus, we conducted studies with two corn stages (R1 and R3) and four corn plant zones (tassel, above ear, ear zone, and below ear) in the field at Concord, NE (USA), and in the field and greenhouse at Botucatu, SP (Brazil), to investigate on-plant larval movement. The effects of different corn tissues (opened tassel, closed tassel, silk, kernel, and leaf), two feeding sequence scenarios (closed tassel-leaf-silk-kernel and leaf-silk-kernel), and artificial diet (positive control) on larval survival and development were also evaluated in the laboratory. Ear zone has a strong effect on feeding choice and survival of fall armyworm larvae regardless of reproductive corn stage. Feeding site choice is made by first-instar. Corn leaves of reproductive plants were not suitable for early instar development, but silk and kernel tissues had a positive effect on survival and development of fall armyworm larvae on reproductive stage corn.

Behavior of Orius insidiosus preying on Aphis gossypii reared on transgenic and conventional cotton varieties

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Morfologia e desenvolvimento do sistema reprodutor em três espécies de Isoptera

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Virulência de micro-organismos à Plutella xylostella (L.) (Lepidoptera: Plutellidae) e compatibilidade com inseticidas

Pós-graduação em Agronomia (Entomologia Agrícola) - FCAV

Resistência de genótipos de palma de óleo (Elaeis guineensis Jacq.) ao ataque de Opsiphanes invirae Hübner, 1808 (lepidoptera: nymphalidae) no Estado do Pará

Pós-graduação em Agronomia (Entomologia Agrícola) - FCAV

Contributions of demography and dispersal parameters to the spatial spread of a stage-structured insect invasion

Stage-structured models that integrate demography and dispersal can be used to identify points in the life cycle with large effects on rates of population spatial spread, information that is vital in the development of containment strategies for invasive species. Current challenges in the application of these tools include: (1) accounting for large uncertainty in model parameters, which may violate assumptions of ‘‘local’’ perturbation metrics such as sensitivities and elasticities, and (2) forecasting not only asymptotic rates of spatial spread, as is usually done, but also transient spatial dynamics in the early stages of invasion. We developed an invasion model for the Diaprepes root weevil (DRW; Diaprepes abbreviatus [Coleoptera: Curculionidae]), a generalist herbivore that has invaded citrus-growing regions of the United States. We synthesized data on DRW demography and dispersal and generated predictions for asymptotic and transient peak invasion speeds, accounting for parameter uncertainty. We quantified the contributions of each parameter toward invasion speed using a ‘‘global’’ perturbation analysis, and we contrasted parameter contributions during the transient and asymptotic phases. We found that the asymptotic invasion speed was 0.02–0.028 km/week, although the transient peak invasion speed (0.03– 0.045 km/week) was significantly greater. Both asymptotic and transient invasions speeds were most responsive to weevil dispersal distances. However, demographic parameters that had large effects on asymptotic speed (e.g., survival of early-instar larvae) had little effect on transient speed. Comparison of the global analysis with lower-level elasticities indicated that local perturbation analysis would have generated unreliable predictions for the responsiveness of invasion speed to underlying parameters. Observed range expansion in southern Florida (1992–2006) was significantly lower than the invasion speed predicted by the model. Possible causes of this mismatch include overestimation of dispersal distances, demographic rates, and spatiotemporal variation in parameter values. This study demonstrates that, when parameter uncertainty is large, as is often the case, global perturbation analyses are needed to identify which points in the life cycle should be targets of management. Our results also suggest that effective strategies for reducing spread during the asymptotic phase may have little effect during the transient phase. Includes Appendix.

Resistência de genótipos de palma de óleo (Elaeis guineensis Jacq.) ao ataque de Opsiphanes invirae Hübner, 1808 (lepidoptera: nymphalidae) no Estado do Pará

Pós-graduação em Agronomia (Entomologia Agrícola) - FCAV

A new Brazilian species of Loxandrus LeConte, 1852, with description of immatures and notes on natural history (Coleoptera: Carabidae: Loxandrini)

Loxandrus oophagus sp. nov. is described (type-locality: Uberlandia, State of Minas Gerais, Brazil). Larvae, pupae and adults of the new species of the carabid beetle were collected on foam nests of the anuran Leptodactylus fuscus (Schneider, 1799) in the surroundings of Uberlandia, 18 degrees 55S, 48 degrees 17W (Brazil, Minas Gerais), at 750 m altitude. The new species is compared with the similar Loxandrus quinarius Will & Liebherr, 1997, only known from Santa Cruz, Bolivia, differing by the morphology of tarsomeres. Larvae prey on anuran eggs. Description of the immatures and the natural history of the species are provided. The larva differs from the known larvae of Loxandrus species mainly by being eruciform, glabrous and depigmented, its small head and legs, and the lack of stemmata and urogomphi, representing an unusual last instar type among the Carabidae.