Large scale mass rearing of natural enemies has been a mean of improving biological control in the sugarcane intensive agriculture. Among them, Cotesia flavipes, a gregarious koinobiont endoparasitoid, was imported by Brasil to control caterpillars of the sugarcane borer Diatraea saccharalis. The C. flavipes larval development depends on its association with polydnavirus, which blocks the host defense reaction. To verify if the oviposition sequence (1st, 2nd or 3rd) and the female condition (mated or virgin) interfere in the number of C. flavipes descendents, 4th instar caterpillars of D. saccharalis were parasitized. Analysis of the data showed that: a) there is an inverse correlation between the parasitism efficiency and the host reaction (encapsulation); b) the number of caterpillars parasitized by virgin females that released parasitoid larvae in the period from 12 to 15 days was higher than that of caterpillars parasitized by mated females; c) a slight difference between mated and virgin females in relation to the parasitim success was observed; and d) the number of encapsulated parasitoid larvae was higher than that of eggs, suggesting that eggs have a better capacity to overcome the host reaction. In this study, the viability of C. flavipes eggs and larvae in the non-specific host D. saccharalis could be correlated with the oviposition sequence and the female condition.

Neste trabalho analisamos as implicações espaciais da distância máxima de vôo para algumas espécies de meliponíneos. Os dados sugerem que a distância máxima de vôo em meliponíneos está relacionada ao tamanho do corpo, especialmente ao tamanho generalizado das asas, que pode ser estimado utilizando análises de componentes principais. Uma análise utilizando seis espécies de meliponíneos evidenciou que o tamanho generalizado das asas está fortemente correlacionado à distância de vôo (r = 0,938). Isso sugere que espécies de meliponíneos ocupam área efetivamente maior quanto maior for o tamanho do corpo, trazendo importantes implicações para a dinâmica espacial de populações locais restritas a áreas fragmentadas. Neste trabalho, também utilizamos um modelo de regressão linear a fim de estimar as distâncias máximas de vôo para 12 outras espécies de meliponíneos. Esta pesquisa fornece subsídios para futuros estudos relacionados à conservação da biodiversidade.

We examined the spatial implications of maximum flight distance for several species of stingless bees. Data suggested that maximum flight distance in Meliponini is a function of body size, especially generalized wing size, which can be estimated through principal component analysis. For six species of stingless bees, flight distances and generalized wing sizes were highly correlated (r = 0.938). This indicates that species of Meliponini occupy an effectively larger area as body size increases, which has important implications in the spatial dynamics of local populations restricted to forest fragments. We also used the fitted linear regression model to estimate the maximum flight distance for 12 other species of Meliponini. The results of this research may provide insights for future studies of biological conservation.

Cotesia glomerata is a natural enemy of the vegetable plague Ascia monuste orseis and preferably parasites 2nd, 3rd and 4th instar larvae. Parasitism effects on the haemolymph protein profile of Ascia monuste orseis larvae from the 2nd to 7th days were analyzed both qualitatively and quantitatively by SDS-PAGE and Coomassie-Blue binding methods. Quantitative analysis showed a progressive increase in the protein content of about 6.5 and 12.5 times in parasitized and non-parasitized larvae from the 2nd to 5th days, respectively. On the 6th day, a decrease in protein content was observed in both groups, although this decrease was significantly less than the control group that continued to metamorphosis. Meanwhile, parasitized larvae had one more day (7th day) in their larval period to complete parasitoid development, justified by the fact that parasitoid is koinobiont and allows host feeding. On this day, a drastic increase in protein content was detected when the parasitoids left the host. The SDS-PAGE showed proteins of high molecular weight (>120 kDa) on the 5th day of the non-parasitized larvae when they entered pre-pupa stage and on the 7th day of parasitized larvae. Proteins with MW lower than 62 kDa and higher than 27 kDa were absent on the 5th day in control larvae (pre-pupa phase), but present in parasitized larvae. This could indicate a possible relation between these proteins and the host juvenile hormone. Therefore, the presence of C. glomerata influences Ascia monuste orseis development, but its own physiological development is apparently independent of the host, which tends to die when parasitism succeeds.

Antenas com malformações diversas, extraídas de zangões de Apis mellifera de ocelos claros, foram desenhadas e dissecadas para a contagem de discos olfativos dos segmentos morfologicamente alterados, em comparação com as antenas normais de seus irmãos. Alguns zangões apresentaram anormalidades morfológicas em um dos segmentos da antena direita ou esquerda, mas outros possuíam dois ou mais segmentos alterados na mesma antena. Zangões com malformações em ambas as antenas também foram observados. Os segmentos 4 e 5 do flagelo foram os mais freqüentemente afetados. Em um menor número de casos, a freqüência de discos olfativos nos segmentos malformados não diferiu significativamente em relação à observada nos segmentos normais. Contudo, na maioria dos casos estudados, as malformações antenais ocasionaram uma significativa redução no número de discos olfativos dos segmentos malformados.

Malformed antennae of Apis mellifera light ocelli drones were drawn, dissected and mounted permanently on slides containing Canada balsam, in order to count the olfactory discs present in each segment, in comparison with the number of those structures in normal antennae of their brothers. Some drones presented morphological abnormalities in a single segment of the right or left antenna, but others had two or more malformed segments in a same antenna. Drones with malformations in both antennae were also observed. The 4th and 5th flagellum segments were the most frequently affected. In a low number of cases the frequency of olfactory discs in malformed segments did not differ from that one recorded for normal segments. However, in most cases studied, the antennal malformations brought about a significant reduction in the number of olfactory discs from malformed segments.

Some properties of a Africanized honeybee venom proteases were determined by enzymatic assays in solution, electrophoresis in SDS-PAGE, and gel filtration. Bee venom extracts were obtained by reservoir disruption, selective dialysis (cut off 12 kDa) to eliminate small components, such as the protease inhibitor present in the venom, and then fractionation of the dialyzed extract by gel filtration on a Sephadex G-100 column. The optimal conditions for the caseinolytic assays were pH 9.5, 2-hour digestion at 37 °C, and 1% casein concentration. The proteolytic activity was also determined by electrophoresis in SDS-PAGE with co-polymerized gelatin with three major bands of 66.0, 41.6, and 25.1 kDa. A principal serine-protease-like mechanism was revealed in the enriched fraction of proteolytic activity.

The effect of pheromones and their chemical analogues in honeybee alarm behaviors was studied in observation boxes. Defensive behaviors, as follows: a) attraction to scent source, b) elevation of wings in "V", c) abdomen elevation, d) abdomen elevation and pumping and e) first leg pair elevation had been temporarily registered when the following compounds were presented: isoamyl alcohol, octyl alcohol, benzyl alcohol, n-butyl acetate, n-octyl acetate, isopentyl acetate, benzyl acetate and 2-heptanone. The results were as follows: 1. the bees elicited some characteristic behaviors when chemical alarm messages were presented, 2. agression (stinging) was not completed with any compound tested, probably because there was not a target (visual stimulus), 3. in all situations the attraction to scent source was low, 4. all the behaviors were elicited in a temporarily different way, 5. the compounds that elicited stronger responses and a greater number of the investigated behaviors were: isopentyl acetate, 2-heptanone, octyl acetate and n-octyl alcohol. In all situations, the first behavior response (and the most intense one) was the elevation and pumping the abdomen. This suggests that the chemical message was promptly recognized and then transmitted to each worker. So, the results obtained in the present work, suggest that chemical alarm messages may be recognized by different mechanisms of neural integration.

A comparison among the profiles of molecular exclusion chromatography in Sephadex G 100 column of venoms from Apis mellifera adansonii and Africanized honeybees revealed unique peaks which might be used to identify these populations. The venoms from hybrid populations resulting from the reciprocal mating of Apis mellifera adansonii and Africanized honeybees presented unique peaks, probably resulting from a synergistic effect between the parental genomes. The occurrence of characteristic peaks in venoms of hybrid populations might be used to identify these populations as well as to distinguish them from their parents.