Efeito da densidade de ninfas de Aphis gossypii Glover, 1877 (Hemiptera, Aphididae) no consumo alimentar e aspectos biológicos de Orius insidiosus (Say, 1832) (Hemiptera, Anthocoridae)

Orius insidiosus (SAY, 1832) is an important predator for biological pest control programs. The objective of this work was to evaluate the functional response, predation capacity and reproductive aspects of O. insidiosus when predating 1, 5, 10, 15, and 20 third/fourth instar nymphs of Aphis gossypii. The tests were conducted under laboratory conditions. Females of the predator were individually maintained in Petri dishes with a cotton leaf at each one of the aphid densities. The average rate of predation was of 0.93 [plus or minus] 0.13, 3.58 [plus or minus] 0.80, 7.31 [plus or minus] 1.45, 7.40 [plus or minus] 1.16, and 10.54 [plus or minus] 1.84 at the densities of 1, 5, 10, 15, and 20 aphids, respectively. The results showed an attack rate of 0.10 h-1 and 1.82 h of manipulation time. The predator spent 3.10 to 4.08 h feeding on leaf cotton glands; this behavior was not directly influenced by the prey density. The proportion of egg laying per female grew up to the density of 10 nymphs whereas the number of eggs per laying increased with the number of available preys.

Efeito de cultivares de algodoeiro sobre a biologia e capacidade predatória de Orius Insidiosus (say, 1832) (hemiptera: anthocoridae) predando Aphis Gossypii Glover, 1877 (Hemiptera: Aphididae)

The objective of this research was to determine the survival, reproduction and predaceous capacity of Orius insidiosus on cotton aphid Aphis gossypii. Cotton plants of Antares, CNPA7H and Acala 90 cultivars (respectively, without tricome, medium tricome density and high tricome density) were individualized and infested with 15 third/fourth instar nymphs of A. gossypii, and then first-instar nymphs of O. insidiosus were released on the plants. The evaluations were made daily, quantifying survival and nymphal development; the number of cotton aphids A. gossypii per day and total; the number of eggs and the population of the predator (number of insects by female); and the conversion efficiency of A. gossypii predaceous. The nymphal development did not differ according to the cotton cultivars. The Antares cultivar favored a higher daily predation rate for the 1st, 2nd and 4th instars and adults of O. insidiosus. The number of eggs and nymphs was smaller when O. insidiosus females were confined on the Acala 90 cultivar. According to the predation rate of O. insidiosus, the efficiency of alimentary conversion was determined for the Antares, CNPA7H and Acala 90 cultivars, being respectively, 4.28, 3.00 and 2.75 cotton aphid predation for each egg of the predator.

Effect of Diets on Biology of Abaris basistriata and Selenophorus seriatoporus (Coleoptera: Carabidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Canibalismo em larvas de matrinxã, Brycon cephalus, após imersão dos ovos à diferentes concentrações de triiodotironina (T3)

The present work evaluated larvae cannibalism of matrinxa, Brycon cephalus, originated from eggs exposed to triiodothyronine, in the period of 36 to 72 hours after hatching. Observed parameters were: weight and length of larvae, stomach content, presence of cannibalism and type of attacks. This study was carried out at Centro de Pesquisa e Gestao de Recursos Pesqueiros Continentais (CEPTA/IBAMA), Pirassununga-SP, in November 2004. Three females were hormonally induced to spawn and pooled oocytes were fertilized and separated into four batches that constituted the treatments: L-1 (control - water); L-2 (0.01 ppm T-3); L-3 (0.05 ppm T-3) and L-4 (0.1 ppm T-3). Eggs were exposed during 15 minutes to water or to solutions containing the different concentrations of T3. Eggs were distributed in 12 conic incubators (60 L), with three replicates per treatment. There was stocked 500 mL of eggs per incubator and hatched larvae were counted. Samples of 30 larvae per treatment were colleted during occurrence of cannibalism (36, 48, 60 and 72 hours post hatching). Predator larvae (with rests of larvae in the stomach) were 50% of the total number of larvae and they presented weight 50% higher compared to that of non predator larvae (without rests of larvae in the stomach) and 9% higher regarding length. Coefficient of variation of weight and length did not differ among treatments, showing similarity in relation to the size. The stomach content revealed that cannibalism occurred in around 50-60 % of larvae, regardless the exposure to the triiodothyronine, and attacks were characterized as head-tail and tail-head attacks.

Genetic diversity and population structure of pumas (Puma concolor) in southeastern Brazil: implications for conservation in a human-dominated landscape

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

Ciclo biológico e predação de três espécies de coccinelídeos (Coleoptera, Coccinellidae) sobre o pulgão-gigante-do-pinus Cinara atlantica (Wilson) (Hemiptera, Aphididae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Occurrence of Atopozelus opsimus preying on nymphs and adults of Glycaspis brimblecombei

The stink bugs genus Atopozelus (Hemiptera: Reduviidae) is native in the Americas, with five described species of which only three have been recorded in Brazil. In August 2007, Eucalyptus camaldulensis leaves infested by lerp psyllid were collected and taken to the Forest Pest Biological Control Laboratory situated at São Paulo State University. A small green stink bug, identified as Atopozelus opsimus Elkins (Hemiptera: Reduviidae) that fed on nymphs and adult psyllids, was found on the leaves. These stink bugs presented phytophagy, omnivory and ability in opening the lerp (shell) that protect the psyllid. A. opsimus has demonstrated unusual particularities, different from many biological control agents found in nature; this predator thus deserves more attention for its potential to be evaluated.

Desenvolvimento e capacidade de consumo de Chrysoperla externa (Hagen, 1861) alimentada com ninfas de mosca-branca criadas em hortaliças

Many arthropods are mentioned with whitefly natural enemies, including the green lacewings. The aim of this study is to analyses the development and the capacity of predation of Chrysoperla externa (Hagen, 1861) fed with Bemisia tabaci B biotype nymphs, rearing different vegetables (kale, broccoli, eggplant end tomato). The duration, viability end weight in each stage end phase of development of the insect-predator had been evaluated, as well as the predatory capacity of the larvae in the third instar. The larval phase of the predator presented minor duration when these had been fed with nymphs developed the broccoli (12.36 days) and minor duration of the tomato (14.36 days) phase when fed with nymphs developed in kale, broccoli, and eggplant (6.50, 7.20, 7.33 days, respectively). The lower indices of viability been found for the larvae fed with nymphs developed in the tomato (30%), and average weights have. The predatory capacity of the larvae during the third instar was not affected, independently on the plant host where the whitefly nymph fed itself.

Avaliação da esporulação de Bionectria ochroleuca em diferentes meios de culturas

The biological control of the plants diseases, caused by fungi, is carried out using others organisms (predator, parasite or pathogen). Among the possible agents of biocontrol, a fungus has been highlighting as promising and it is known as Clonostachys rosea, asexual form of Bionectria ochroleuca. For that, it is necessary the in vitro production of spores of this fungus. In this study were tested several culture media to select those with better conidia production. The study was conducted at Plant Protection Division, in the Plant Production Department, FCA - UNESP, Botucatu campus, São Paulo state, Brazil. We used the isolated CCR64 (Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA)-CNPMA). The means of crops were: BDA; Oats-Agar; Mazeina-Agar; Rice-Agar; V8-5%; V8-10%; V8-20%; TJ-5 %; TJ-10, TJ-20%. The sporulation of the fungus in different culture media was estimated at 8 days after of the incubation. The data were analyzed using method of comparing averages, using the Tukey test, at 5% probability, and the data processed, using (X + 1) 0.5 transformation. All culture media tested were able to produce conidia. It was found that the best culture media for production of conidia of Bionectria ochroleuca is the TJ-5%, followed by TJ-20%, with an sporulation average of 3,5 x 106 conidia / ml.

Physical environment modulates the behavioral responses induced by chemical stimulation of dorsal periaqueductal gray in mice

In order to investigate the relationship between behaviors elicited by chemical stimulation of the dorsal periaqueductal gray (dorsal PAG) and spontaneous defensive behaviors to a predator, the excitatory amino acid D,L-homocysteic acid (5 nmol in 0.1 mu l), was infused into the dorsal PAG and behavioral responses of mice were evaluated in two different situations, a rectangular novel chamber or the Mouse Defense Test Battery (MDTB) apparatus. During a 1-min period following drug infusion, more jumps were made in the chamber than in the MDTB runway but running time and distance traveled were significantly higher in the runway. Animals were subsequently tested using the standard MDTB procedure (anti-predator avoidance, chase and defensive threat/attack). No drug effects on these measures were significant. In a further test in the MDTB apparatus, the pathway of the mouse during peak locomotion response was blocked 3 times by the predator stimulus (anesthetized rat) to determine if the mouse would avoid contact. Ninety percent of D,L-homocysteic treated animals made direct contact with the stimulus (rat), indicating that D,L-homocysteic-induced running is not guided by relevant (here, threat) stimuli. These results indicate that running as opposed to jumping is the primary response in mice injected with D,L-homocysteic into the dorsal PAG when the environment enables flight. However, the lack of responsivity to the predator during peak locomotion suggests that D,L-homocysteic-stimulation into the dorsal PAG does not induce normal antipredator flight. (c) 2006 Published by Elsevier B.V.

Investigation of the hypothalamic defensive system in the mouse

The hypothalamus plays especially important roles in various endocrine, autonomic, and behavioral responses that guarantee the survival of both the individual and the species. In the rat, a distinct hypothalamic defensive circuit has been defined as critical for integrating predatory threats, raising an important question as to whether this concept could be applied to other prey species. To start addressing this matter, in the present study, we investigated, in another prey species (the mouse), the pattern of hypothalamic Fos immunoreactivity in response to exposure to a predator (a rat, using the Rat Exposure Test). During rat exposure, mice remained concealed in the home chamber for a longer period of time and increased freezing and risk assessment activity. We were able to show that the mouse and the rat present a similar pattern of hypothalamic activation in response to a predator. of particular note, similar to what has been described for the rat, we observed in the mouse that predator exposure induces a striking activation in the elements of the medial hypothalamic defensive system, namely, the anterior hypothalamic nucleus, the dorsomedial part of the ventromedial hypothalamic nucleus and the dorsal premammillary nucleus. Moreover, as described for the rat, predator-exposed mice also presented increased Fos levels in the autonomic and parvicellular parts of the paraventricular hypothalamic nucleus, lateral preoptic area and subfornical region of the lateral hypothalamic area. In conclusion, the present data give further support to the concept that a specific hypothalamic defensive circuit should be preserved across different prey species. (C) 2008 Elsevier B.V. All rights reserved.

Role of nitric oxide in the periaqueductal gray in defensive behavior in mice: influence of prior local N-methyl-D-aspartate receptor activation and aversive condition

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

Composição acarina em diferentes cultivares de pessegueiros [Prunus persica (L.)], em Presidente Prudente, estado de São Paulo

Objetivou-se, nesta pesquisa, estudar a ocorrência natural de ácaros fitófagos e predadores em diferentes cultivares de pessegueiro, no município de Presidente Prudente-SP, Brasil. O estudo foi realizado no período de dezembro de 2002 a fevereiro de 2006. Amostras quinzenais de 72 folhas foram coletadas ao acaso, de pessegueiros das cultivares Talismã, Doçura 2, Dourado 2, Tropical, Aurora 1 e Aurora 2. Coletou-se um total de 2.594 ácaros, sendo 2.092 fitófagos, 403 predadores e 99 de hábitos alimentares pouco conhecidos, com 35 espécies de ácaros de 16 famílias. Aculus fockeui ocorreu de maneira esporádica, não causando danos visíveis às plantas. A família Phytoseiidae apresentou a maior abundância e o maior número de indivíduos. O predador Euseius citrifolius foi o mais abundante. Não houve preferência dos ácaros nas cultivares de pessegueiro avaliadas.

Cannibalistic behavior and functional response in Chrysomya albiceps (Diptera : Calliphoridae)

Chrysomya albiceps is a facultative predator and cannibal species during the larval stage. Very little is known about cannibalism and prey size preference, especially in blowflies. The purpose of this investigation was to determine the influence of prey size and larval density on cannibalism by third-instar larvae of C. albiceps under laboratory conditions. Our results indicate that no cannibalism occurs by third-instar larvae on first- and second-instar larvae, but third-instar larvae do eat second-instar larvae. The functional response on second-instar larvae is consistent with Holling type II. The consequences of consuming second-, compared to first- or third-, instar larvae as well as the implications of cannibalism for the population dynamics of C. albiceps are discussed.

Ecological modeling and pest population management: a possible and necessary connection in a changing world

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